Recalculation of dose for each fraction of treatment on TomoTherapy.

PubMed

Thomas, Simon J; Romanchikova, Marina; Harrison, Karl; Parker, Michael A; Bates, Amy M; Scaife, Jessica E; Sutcliffe, Michael P F; Burnet, Neil G

2016-01-01

The VoxTox study, linking delivered dose to toxicity requires recalculation of typically 20-37 fractions per patient, for nearly 2000 patients. This requires a non-interactive interface permitting batch calculation with multiple computers. Data are extracted from the TomoTherapy(®) archive and processed using the computational task-management system GANGA. Doses are calculated for each fraction of radiotherapy using the daily megavoltage (MV) CT images. The calculated dose cube is saved as a digital imaging and communications in medicine RTDOSE object, which can then be read by utilities that calculate dose-volume histograms or dose surface maps. The rectum is delineated on daily MV images using an implementation of the Chan-Vese algorithm. On a cluster of up to 117 central processing units, dose cubes for all fractions of 151 patients took 12 days to calculate. Outlining the rectum on all slices and fractions on 151 patients took 7 h. We also present results of the Hounsfield unit (HU) calibration of TomoTherapy MV images, measured over an 8-year period, showing that the HU calibration has become less variable over time, with no large changes observed after 2011. We have developed a system for automatic dose recalculation of TomoTherapy dose distributions. This does not tie up the clinically needed planning system but can be run on a cluster of independent machines, enabling recalculation of delivered dose without user intervention. The use of a task management system for automation of dose calculation and outlining enables work to be scaled up to the level required for large studies.

Improvements in dose calculation accuracy for small off-axis targets in high dose per fraction tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hardcastle, Nicholas; Bayliss, Adam; Wong, Jeannie Hsiu Ding

2012-08-15

Purpose: A recent field safety notice from TomoTherapy detailed the underdosing of small, off-axis targets when receiving high doses per fraction. This is due to angular undersampling in the dose calculation gantry angles. This study evaluates a correction method to reduce the underdosing, to be implemented in the current version (v4.1) of the TomoTherapy treatment planning software. Methods: The correction method, termed 'Super Sampling' involved the tripling of the number of gantry angles from which the dose is calculated during optimization and dose calculation. Radiochromic film was used to measure the dose to small targets at various off-axis distances receivingmore » a minimum of 21 Gy in one fraction. Measurements were also performed for single small targets at the center of the Lucy phantom, using radiochromic film and the dose magnifying glass (DMG). Results: Without super sampling, the peak dose deficit increased from 0% to 18% for a 10 mm target and 0% to 30% for a 5 mm target as off-axis target distances increased from 0 to 16.5 cm. When super sampling was turned on, the dose deficit trend was removed and all peak doses were within 5% of the planned dose. For measurements in the Lucy phantom at 9.7 cm off-axis, the positional and dose magnitude accuracy using super sampling was verified using radiochromic film and the DMG. Conclusions: A correction method implemented in the TomoTherapy treatment planning system which triples the angular sampling of the gantry angles used during optimization and dose calculation removes the underdosing for targets as small as 5 mm diameter, up to 16.5 cm off-axis receiving up to 21 Gy.« less

Re-Shielding of Cobalt-60 Teletherapy Rooms for Tomotherapy and Conventional Linear Accelerators using Monte Carlo Simulations

NASA Astrophysics Data System (ADS)

Çeçen, Yiğit; Yazgan, Çağrı

2017-09-01

Purpose. Nearly all Cobalt-60 teletherapy machines were removed around the world during the last two decades. The remaining ones are being used for experimental purposes. However, the rooms of these teletherapy machines are valuable because of lack of space in radiotherapy clinics. In order to place a new technology treatment machine in one of these rooms, one should re-shield the room since it was designed only for 1.25 MeV gamma beams on average. Mostly, the vendor of the new machine constructs the new shielding of the room using their experience. However, every radiotherapy room has different surrounding work areas and it would be wise to shield the room considering these special conditions. Also, the shield design goal of the clinic may be much lower than the International Atomic Energy Agency (IAEA) or the local association accepts. The study shows re-shielding of a Cobalt-60 room, specific to the clinic, using Monte Carlo simulations. Materials & Methods: First, a 6 MV Tomotherapy machine, then a 10 MV conventional linear accelerator (LINAC) was placed inside the Cobalt-60 teletherapy room. The photon flux outside the room was simulated using Monte Carlo N-Particle (MCNP6.1) code before and after re-shielding. For the Tomotherapy simulation, flux distributions around the machine were obtained from the vendor and implemented as the source of the model. The LINAC model was more generic with the 10 MeV electron source, the tungsten target, first and secondary collimators. The aim of the model was to obtain the maximum (40x40 cm2) open field at the isocenter. Two different simulations were carried out for gantry angles 90o and 270o. The LINAC was placed in the room such that the primary walls were A' (Gantry 270o) and C' (Gantry 90o) (figure 1). The second part of the study was to model the re-shielding of the room for Tomotherapy and for the conventional LINAC, separately. The aim was to investigate the recommended shielding by the vendors. Left side of the room was adjacent to a LINAC room with 2 meters thick concrete wall (figure 1). No shielding was necessary for that wall. Behind wall A-A' there was an outdoors forbidden area; behind wall B-B' was the contouring room for the doctors; and the control room was behind wall C-C' (figure 1). After some modifications, the final shielding was designed. Results: The photon flux distributions outside the room before and after the re-shielding were compared. The re-shielding of Tomotherapy reduced the flux down to 1.89 % on average with respect to pre-shielding (table 1). For the conventional LINAC case; after re-shielding, the photon flux in the control room -which corresponds to gantry 90°- decreased down to 0.57% with respect to pre-shielding (table 2). The photon flux behind wall A' -which corresponds to gantry 270°- decreased down to 2.46%. Everybody was all safe behind wall B' even before re-shielding.

Planning evaluation of radiotherapy for complex lung cancer cases using helical tomotherapy

NASA Astrophysics Data System (ADS)

Kron, Tomas; Grigorov, Grigor; Yu, Edward; Yartsev, Slav; Chen, Jeff Z.; Wong, Eugene; Rodrigues, George; Trenka, Kris; Coad, Terry; Bauman, Glenn; Van Dyk, Jake

2004-08-01

Lung cancer treatment is one of the most challenging fields in radiotherapy. The aim of the present study was to investigate what role helical tomotherapy (HT), a novel approach to the delivery of highly conformal dose distributions using intensity-modulated radiation fan beams, can play in difficult cases with large target volumes typical for many of these patients. Tomotherapy plans were developed for 15 patients with stage III inoperable non-small-cell lung cancer. While not necessarily clinically indicated, elective nodal irradiation was included for all cases to create the most challenging scenarios with large target volumes. A 2 cm margin was used around the gross tumour volume (GTV) to generate primary planning target volume (PTV2) and 1 cm margin around elective nodes for secondary planning target volume (PTV1) resulting in PTV1 volumes larger than 1000 cm3 in 13 of the 15 patients. Tomotherapy plans were created using an inverse treatment planning system (TomoTherapy Inc.) based on superposition/convolution dose calculation for a fan beam thickness of 25 mm and a pitch factor between 0.3 and 0.8. For comparison, plans were created using an intensity-modulated radiation therapy (IMRT) approach planned on a commercial treatment planning system (TheraplanPlus, Nucletron). Tomotherapy delivery times for the large target volumes were estimated to be between 4 and 19 min. Using a prescribed dose of 60 Gy to PTV2 and 46 Gy to PTV1, the mean lung dose was 23.8 ± 4.6 Gy. A 'dose quality factor' was introduced to correlate the plan outcome with patient specific parameters. A good correlation was found between the quality of the HT plans and the IMRT plans with HT being slightly better in most cases. The overlap between lung and PTV was found to be a good indicator of plan quality for HT. The mean lung dose was found to increase by approximately 0.9 Gy per percent overlap volume. Helical tomotherapy planning resulted in highly conformal dose distributions. It allowed easy achievement of two different dose levels in the target simultaneously. As the overlap between PTV and lung volume is a major predictor of mean lung dose, future work will be directed to control of margins. Work is underway to investigate the possibility of breath-hold techniques for tomotherapy delivery to facilitate this aim.

Helical tomotherapy significantly reduces dose to normal tissues when compared to 3D-CRT for locally advanced rectal cancer.

PubMed

Jhaveri, Pavan M; Teh, Bin S; Paulino, Arnold C; Smiedala, Mindy J; Fahy, Bridget; Grant, Walter; McGary, John; Butler, E Brian

2009-10-01

Combined modality treatment (neoadjuvant chemoradiotherapy followed by surgery) for locally advanced rectal cancer requires special attention to various organs at risk (OAR). As a result, the use of conformal dose delivery methods has become more common in this disease setting. Helical tomotherapy is an image-guided intensity modulated delivery system that delivers dose in a fan-beam manner at 7 degree intervals around the patient and can potentially limit normal tissue from high dose radiation while adequately treating targets. In this study we dosimetrically compare helical tomotherapy to 3D-CRT for stage T3 rectal cancer. The helical tomotherapy plans were optimized in the TomoPlan system to achieve an equivalent uniform dose of 45 Gy for 10 patients with T3N0M0 disease that was at least 5cm from the anal verge. The GTV included the rectal thickening and mass evident on colonoscopy and CT scan as well as with the help of a colorectal surgeon. The CTV included the internal iliac, obturator, and pre-sacral lymphatic chains. The OAR that were outlined included the small bowel, pelvic bone marrow, femoral heads, and bladder. Anatom-e system was used to assist in delineating GTV, CTV and OAR. These 10 plans were then duplicated and optimized into 3-field 3D-CRT plans within the Pinnacle planning system.The V[45], V[40], V[30], V[20], V[10], and mean dose to the OAR were compared between the helical tomotherapy and 3D-CRT plans. Statistically significant differences were achieved in the doses to all OAR, including all volumes and means except for V[10] for the small bowel and the femoral heads. Adequate dosimetric coverage of targets were achieved with both helical tomotherapy and 3D-CRT. Helical tomotherapy reduces the volume of normal tissue receiving high-dose RT when compared to 3D-CRT treatment. Both modalities adequately dose the tumor. Clinical studies addressing the dosimetric benefits are on-going.

TU-AB-BRC-10: Modeling of Radiotherapy Linac Source Terms Using ARCHER Monte Carlo Code: Performance Comparison of GPU and MIC Computing Accelerators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, T; Lin, H; Xu, X

Purpose: (1) To perform phase space (PS) based source modeling for Tomotherapy and Varian TrueBeam 6 MV Linacs, (2) to examine the accuracy and performance of the ARCHER Monte Carlo code on a heterogeneous computing platform with Many Integrated Core coprocessors (MIC, aka Xeon Phi) and GPUs, and (3) to explore the software micro-optimization methods. Methods: The patient-specific source of Tomotherapy and Varian TrueBeam Linacs was modeled using the PS approach. For the helical Tomotherapy case, the PS data were calculated in our previous study (Su et al. 2014 41(7) Medical Physics). For the single-view Varian TrueBeam case, we analyticallymore » derived them from the raw patient-independent PS data in IAEA’s database, partial geometry information of the jaw and MLC as well as the fluence map. The phantom was generated from DICOM images. The Monte Carlo simulation was performed by ARCHER-MIC and GPU codes, which were benchmarked against a modified parallel DPM code. Software micro-optimization was systematically conducted, and was focused on SIMD vectorization of tight for-loops and data prefetch, with the ultimate goal of increasing 512-bit register utilization and reducing memory access latency. Results: Dose calculation was performed for two clinical cases, a Tomotherapy-based prostate cancer treatment and a TrueBeam-based left breast treatment. ARCHER was verified against the DPM code. The statistical uncertainty of the dose to the PTV was less than 1%. Using double-precision, the total wall time of the multithreaded CPU code on a X5650 CPU was 339 seconds for the Tomotherapy case and 131 seconds for the TrueBeam, while on 3 5110P MICs it was reduced to 79 and 59 seconds, respectively. The single-precision GPU code on a K40 GPU took 45 seconds for the Tomotherapy dose calculation. Conclusion: We have extended ARCHER, the MIC and GPU-based Monte Carlo dose engine to Tomotherapy and Truebeam dose calculations.« less

Verification of calculated skin doses in postmastectomy helical tomotherapy.

PubMed

Ito, Shima; Parker, Brent C; Levine, Renee; Sanders, Mary Ella; Fontenot, Jonas; Gibbons, John; Hogstrom, Kenneth

2011-10-01

To verify the accuracy of calculated skin doses in helical tomotherapy for postmastectomy radiation therapy (PMRT). In vivo thermoluminescent dosimeters (TLDs) were used to measure the skin dose at multiple points in each of 14 patients throughout the course of treatment on a TomoTherapy Hi·Art II system, for a total of 420 TLD measurements. Five patients were evaluated near the location of the mastectomy scar, whereas 9 patients were evaluated throughout the treatment volume. The measured dose at each location was compared with calculations from the treatment planning system. The mean difference and standard error of the mean difference between measurement and calculation for the scar measurements was -1.8% ± 0.2% (standard deviation [SD], 4.3%; range, -11.1% to 10.6%). The mean difference and standard error of the mean difference between measurement and calculation for measurements throughout the treatment volume was -3.0% ± 0.4% (SD, 4.7%; range, -18.4% to 12.6%). The mean difference and standard error of the mean difference between measurement and calculation for all measurements was -2.1% ± 0.2% (standard deviation, 4.5%: range, -18.4% to 12.6%). The mean difference between measured and calculated TLD doses was statistically significant at two standard deviations of the mean, but was not clinically significant (i.e., was <5%). However, 23% of the measured TLD doses differed from the calculated TLD doses by more than 5%. The mean of the measured TLD doses agreed with TomoTherapy calculated TLD doses within our clinical criterion of 5%. Copyright © 2011 Elsevier Inc. All rights reserved.

Verification of Calculated Skin Doses in Postmastectomy Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ito, Shima; Parker, Brent C., E-mail: bcparker@marybird.com; Mary Bird Perkins Cancer Center, Baton Rouge, LA

2011-10-01

Purpose: To verify the accuracy of calculated skin doses in helical tomotherapy for postmastectomy radiation therapy (PMRT). Methods and Materials: In vivo thermoluminescent dosimeters (TLDs) were used to measure the skin dose at multiple points in each of 14 patients throughout the course of treatment on a TomoTherapy Hi.Art II system, for a total of 420 TLD measurements. Five patients were evaluated near the location of the mastectomy scar, whereas 9 patients were evaluated throughout the treatment volume. The measured dose at each location was compared with calculations from the treatment planning system. Results: The mean difference and standard errormore » of the mean difference between measurement and calculation for the scar measurements was -1.8% {+-} 0.2% (standard deviation [SD], 4.3%; range, -11.1% to 10.6%). The mean difference and standard error of the mean difference between measurement and calculation for measurements throughout the treatment volume was -3.0% {+-} 0.4% (SD, 4.7%; range, -18.4% to 12.6%). The mean difference and standard error of the mean difference between measurement and calculation for all measurements was -2.1% {+-} 0.2% (standard deviation, 4.5%: range, -18.4% to 12.6%). The mean difference between measured and calculated TLD doses was statistically significant at two standard deviations of the mean, but was not clinically significant (i.e., was <5%). However, 23% of the measured TLD doses differed from the calculated TLD doses by more than 5%. Conclusions: The mean of the measured TLD doses agreed with TomoTherapy calculated TLD doses within our clinical criterion of 5%.« less

SU-E-T-417: The Impact of Normal Tissue Constraints On PTV Dose Homogeneity for Intensity Modulated Radiotherapy (IMRT), Volume Modulated Arc Therapy (VMAT) and Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peng, J; McDonald, D; Ashenafi, M

2014-06-01

Purpose: Complex intensity modulated arc therapy tends to spread low dose to normal tissue(NT)regions to obtain improved target conformity and homogeneity and OAR sparing.This work evaluates the trade-offs between PTV homogeneity and reduction of the maximum dose(Dmax)spread to NT while planning of IMRT,VMAT and Tomotherapy. Methods: Ten prostate patients,previously planned with step-and-shoot IMRT,were selected.To fairly evaluate how PTV homogeneity was affected by NT Dmax constraints,original IMRT DVH objectives for PTV and OARs(femoral heads,and rectal and bladder wall)applied to 2 VMAT plans in Pinnacle(V9.0), and Tomotherapy(V4.2).The only constraint difference was the NT which was defined as body contours excluding targets,OARs andmore » dose rings.NT Dmax constraint for 1st VMAT was set to the prescription dose(Dp).For 2nd VMAT(VMAT-NT)and Tomotherapy,it was set to the Dmax achieved in IMRT(~70-80% of Dp).All NT constraints were set to the lowest priority.Three common homogeneity indices(HI),RTOG-HI=Dmax/Dp,moderated-HI=D95%/D5% and complex-HI=(D2%-D98%)/Dp*100 were calculated. Results: All modalities with similar dosimetric endpoints for PTV and OARs.The complex-HI shows the most variability of indices,with average values of 5.9,4.9,9.3 and 6.1 for IMRT,VMAT,VMAT-NT and Tomotherapy,respectively.VMAT provided the best PTV homogeneity without compromising any OAR/NT sparing.Both VMAT-NT and Tomotherapy,planned with more restrictive NT constraints,showed reduced homogeneity,with VMAT-NT showing the worst homogeneity(P<0.0001)for all HI.Tomotherapy gave the lowest NT Dmax,with slightly decreased homogeneity compared to VMAT. Finally, there was no significant difference in NT Dmax or Dmean between VMAT and VMAT-NT. Conclusion: PTV HI is highly dependent on permitted NT constraints. Results demonstrated that VMAT-NT with more restrictive NT constraints does not reduce Dmax NT,but significantly receives higher Dmax and worse target homogeneity.Therefore, it is critical that planners do not use too restrictive NT constraints during VMAT optimization.Tomotherapy plan was not as sensitive to NT constraints,however,care shall be taken to ensure NT is not pushed too hard.These results are relevant for clinical practice.The biological effect of higher Dmax and increased target heterogeneity needs further study.« less

Helical tomotherapy for radiotherapy in esophageal cancer: a preferred plan with better conformal target coverage and more homogeneous dose distribution.

PubMed

Chen, Yi-Jen; Liu, An; Han, Chunhui; Tsai, Peter T; Schultheiss, Timothy E; Pezner, Richard D; Vora, Nilesh; Lim, Dean; Shibata, Stephen; Kernstine, Kemp H; Wong, Jeffrey Y C

2007-01-01

We compare different radiotherapy techniques-helical tomotherapy (tomotherapy), step-and-shoot IMRT (IMRT), and 3-dimensional conformal radiotherapy (3DCRT)-for patients with mid-distal esophageal carcinoma on the basis of dosimetric analysis. Six patients with locally advanced mid-distal esophageal carcinoma were treated with neoadjuvant chemoradiation followed by surgery. Radiotherapy included 50 Gy to gross planning target volume (PTV) and 45 Gy to elective PTV in 25 fractions. Tomotherapy, IMRT, and 3DCRT plans were generated. Dose-volume histograms (DVHs), homogeneity index (HI), volumes of lung receiving more than 10, 15, or 20 Gy (V(10), V(15), V(20)), and volumes of heart receiving more than 30 or 45 Gy (V(30), V(45)) were determined. Statistical analysis was performed by paired t-tests. By isodose distributions and DVHs, tomotherapy plans showed sharper dose gradients, more conformal coverage, and better HI for both gross and elective PTVs compared with IMRT or 3DCRT plans. Mean V(20) of lung was significantly reduced in tomotherapy plans. However, tomotherapy and IMRT plans resulted in larger V(10) of lung compared to 3DCRT plans. The heart was significantly spared in tomotherapy and IMRT plans compared to 3DCRT plans in terms of V(30) and V(45). We conclude that tomotherapy plans are superior in terms of target conformity, dose homogeneity, and V(20) of lung.

Retrospective evaluation of pediatric cranio-spinal axis irradiation plans with the Hi-ART tomotherapy system.

PubMed

Penagaricano, José A; Yan, Yulong; Corry, Peter; Moros, Eduardo; Ratanatharathorn, Vaneerat

2007-08-01

Helical tomotherapy (HT) can be used for the delivery of cranio-spinal axis irradiation (CSAI) without the need for beam matching of conventional linac-based external beam irradiation. The aim of this study is to retrospectively evaluate HT plans used for treatment in nine patients treated with CSAI. Helical tomotherapy cranio-spinal axis irradiation (HT-CSAI) plans were created for each patient. Average length along the cranio-spinal axis of the PTV was 65.6 cm with a range between 53 and 74 cm. Treatment planning optimization and plan evaluation parameters were obtained from the HT planning station for each of the nine patients. PTV coverage by the 95% isodose surface ranged between 98.0 to 100.0% for all nine patients. The clinically acceptable dose variation within the PTV or tolerance range was between 0.7 and 2.5% for all nine patients. Doses to the organs at risk were clinically acceptable. An increasing length along the longitudinal axis of the PTV did not consistently increase the beam-on time indicating that using a larger jaw width had a greater impact on treatment time. With a larger jaw width it is possible to substantially reduce the normalized beam-on treatment time without compromising plan quality and sparing of organs at risk. By using a larger jaw width or lower modulation factor or both, normalized beam-on times were decreased by up to 61% as compared to the other evaluated treatment plans. From the nine cases reported in this study the minimum beam-on time was achieved with a jaw width of 5.0 cm, pitch of 0.287 and a modulation factor of 2.0. Large and long cylindrical volumes can be effectively treated with helical tomotherapy with both clinically acceptable dose distribution and beam-on time.

Is a quasi-3D dosimeter better than a 2D dosimeter for Tomotherapy delivery quality assurance?

NASA Astrophysics Data System (ADS)

Xing, Aitang; Deshpande, Shrikant; Arumugam, Sankar; George, Armia; Holloway, Lois; Vial, Philip; Goozee, Gary

2015-01-01

Delivery quality assurance (DQA) has been performed for each Tomotherapy patient either using ArcCHECK or MatriXX Evolution in our clinic since 2012. ArcCHECK is a quasi-3D dosimeter whereas MatriXX is a 2D detector. A review of DQA results was performed for all patients in the last three years, a total of 221 DQA plans. These DQA plans came from 215 patients with a variety of treatment sites including head-neck, pelvis, and chest wall. The acceptable Gamma pass rate in our clinic is over 95% using 3mm and 3% of maximum planned dose with 10% dose threshold. The mean value and standard deviation of Gamma pass rates were 98.2% ± 1.98(1SD) for MatriXX and 98.5%±1.88 (1SD) for ArcCHECK. A paired t-test was also performed for the groups of patients whose DQA was performed with both the ArcCHECK and MatriXX. No statistical dependence was found in terms of the Gamma pass rate for ArcCHECK and MatriXX. The considered 3D and 2D dosimeters have achieved similar results in performing routine patient-specific DQA for patients treated on a TomoTherapy unit.

Dosimetric study and in-vivo dose verification for conformal avoidance treatment of anal adenocarcinoma using helical tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han Chunhui; Chen Yijen; Liu An

2007-04-01

This study evaluated the efficacy of using helical tomotherapy for conformal avoidance treatment of anal adenocarcinoma. We retrospectively generated step-and-shoot intensity-modulated radiotherapy (sIMRT) plans and helical tomotherapy plans for two anal cancer patients, one male and one female, who were treated by the sIMRT technique. Dose parameters for the planning target volume (PTV) and the organs-at-risk (OARs) were compared between the sIMRT and the helical tomotherapy plans. The helical tomotherapy plans showed better dose homogeneity in the PTV, better dose conformity around the PTV, and, therefore, better sparing of nearby OARs compared with the sIMRT plans. In-vivo skin dose measurementsmore » were performed during conformal avoidance helical tomotherapy treatment of an anal cancer patient to verify adequate delivery of skin dose and sparing of OARs.« less

Cost Analysis of Complex Radiation Therapy for Patients With Head and Neck Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perrier, Lionel; Morelle, Magali; Department of Clinical Research and Innovation, Leon Berard Cancer Centre, Lyon

2016-06-01

Purpose: This cost analysis aimed to prospectively assess differences in costs between TomoTherapy and volumetric modulated arc therapy (VMAT) in patients with head and neck cancer. Methods and Materials: Economic data were gathered from a multicenter study. However, randomization was not possible due to the availability of equipment. Costs were calculated using the microcosting technique from the hospital's perspective (in 2013 euros), and the time horizon was radiation therapy. Only resources that entered the hospital production process and which were likely to vary between the strategies being compared were considered. Acute adverse events observed within the time horizon were alsomore » assessed. Results: The cost analysis was based on a total of 173 patient treatments given between 2010 and 2012 in 14 French cancer centers: 73 patients were treated with TomoTherapy, 92 with VMAT RapidArc, and 8 with VMAT SmartArc. Estimated costs of SmartArc were removed from the comparison due to the small sample size. The mean ± SD cost per patient of the treatment planning phase was €314 (±€214) for TomoTherapy and €511 (±€590) for RapidArc. Mean costs ± SD per patient of irradiation reached €3144 (±€565) for TomoTherapy and €1350 (±€299) for RapidArc. The most sensitive parameter of irradiation was the annual operating time of accelerators. Ninety-five percent confidence intervals for the mean costs of irradiation were €3016 to €3272 for TomoTherapy and €1281 to €1408 for RapidArc. The number of acute adverse events during radiation therapy was not significantly different between strategies. Conclusions: TomoTherapy appeared to be more expensive than RapidArc mainly due to the higher price of the accelerator, the higher costs of maintenance, and the longer duration of treatment sessions. Because strategies were not significantly different in clinical effect, RapidArc appeared to be the strategy to be recommended at this stage of knowledge.« less

SU-C-210-02: Impact of Intrafractional Motion On TomoTherapy Stereotactic Body Radiotherapy (SBRT) 4D Dosimetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lian, J; Matney, J; Chao, E

2015-06-15

Purpose: TomoTherapy treatment has unique challenges in handling intrafractional motion compared to conventional LINAC. This study is aimed to gain a realistic and quantitative understanding of motion impact on TomoTherapy SBRT treatment of lung and prostate cancer patients. Methods: A 4D dose engine utilizing GPUs and including motion during treatment was developed for the efficient simulation of TomoTherapy delivered dosimetry. Two clinical CyberKnife lung cases with respiratory motion tracking and two prostate cases with a slower non-periodical organ motion treated by LINAC plus Calypso tracking were used in the study. For each disease site, one selected case has an averagemore » motion (6mm); the other has a large motion (10mm for lung and 15mm for prostate). SBRT of lung and prostate cases were re-planned on TomoTherapy with 12 Gyx4 fractions and 7Gyx5 fractions, respectively, all with 95% PTV coverage. Each case was planned with 4 jaw settings: 1) conventional 1cm static, 2) 2.5cm static, 3) 2.5cm dynamic, and 4) 5cm dynamic. The intrafractional rigid motion of the target was applied in the dose calculation of individual fractions of each plan and total dose was accumulated from multiple fractions. Results: For 1cm static jaw plans with motions applied, PTV coverage is related to motion type and amplitude. For SBRT patients with average motion (6mm), the PTV coverage remains > 95% for lung case and 74% for prostate case. For cases with large motion, PTV coverage drops to 61% for lung SBRT and 49% for prostate SBRT. Plans with other jaws improve uniformity of moving target, but still suffer from poor PTV coverage (< 70%). Conclusion: TomoTherapy lung SBRT is less motion-impacted when average amplitude of respiratory-induced intrafractional motion is present (6mm). When motion is large and/or non-periodic (prostate), all studied plans lead to significantly decreased target coverage in actual delivered dosimetry.« less

Cost Analysis of Complex Radiation Therapy for Patients With Head and Neck Cancer.

PubMed

Perrier, Lionel; Morelle, Magali; Pommier, Pascal; Boisselier, Pierre; Coche-Dequeant, Bernard; Gallocher, Olivier; Alfonsi, Marc; Bardet, Etienne; Rives, Michel; Calugaru, Valentin; Chajon, Enrique; Noel, Georges; Mecellem, Hinda; Pérol, David; Dussart, Sophie; Giraud, Philippe

2016-06-01

This cost analysis aimed to prospectively assess differences in costs between TomoTherapy and volumetric modulated arc therapy (VMAT) in patients with head and neck cancer. Economic data were gathered from a multicenter study. However, randomization was not possible due to the availability of equipment. Costs were calculated using the microcosting technique from the hospital's perspective (in 2013 euros), and the time horizon was radiation therapy. Only resources that entered the hospital production process and which were likely to vary between the strategies being compared were considered. Acute adverse events observed within the time horizon were also assessed. The cost analysis was based on a total of 173 patient treatments given between 2010 and 2012 in 14 French cancer centers: 73 patients were treated with TomoTherapy, 92 with VMAT RapidArc, and 8 with VMAT SmartArc. Estimated costs of SmartArc were removed from the comparison due to the small sample size. The mean ± SD cost per patient of the treatment planning phase was €314 (±€214) for TomoTherapy and €511 (±€590) for RapidArc. Mean costs ± SD per patient of irradiation reached €3144 (±€565) for TomoTherapy and €1350 (±€299) for RapidArc. The most sensitive parameter of irradiation was the annual operating time of accelerators. Ninety-five percent confidence intervals for the mean costs of irradiation were €3016 to €3272 for TomoTherapy and €1281 to €1408 for RapidArc. The number of acute adverse events during radiation therapy was not significantly different between strategies. TomoTherapy appeared to be more expensive than RapidArc mainly due to the higher price of the accelerator, the higher costs of maintenance, and the longer duration of treatment sessions. Because strategies were not significantly different in clinical effect, RapidArc appeared to be the strategy to be recommended at this stage of knowledge. Copyright © 2016 Elsevier Inc. All rights reserved.

Clinical Study of Nasopharyngeal Carcinoma Treated by Helical Tomotherapy in China: 5-Year Outcomes

PubMed Central

Du, Lei; Zhang, Xin-Xin; Ma, Lin; Feng, Lin-Chun; Li, Fang; Zhou, Gui-Xia; Qu, Bao-Lin; Xu, Shou-Ping; Xie, Chuan-Bin; Yang, Jack

2014-01-01

Background. To evaluate the outcomes of nasopharyngeal carcinoma (NPC) patients treated with helical tomotherapy (HT). Methods. Between September 2007 and August 2012, 190 newly diagnosed NPC patients were treated with HT. Thirty-one patients were treated with radiation therapy as single modality, 129 with additional cisplatin-based chemotherapy with or without anti-EGFR monoclonal antibody therapy, and 30 with concurrent anti-EGFR monoclonal antibody therapy. Results. Acute radiation related side effects were mainly grade 1 or 2. Grade 3 and greater toxicities were rarely noted. The median followup was 32 (3–38) months. The local relapse-free survival (LRFS), nodal relapse-free survival (NRFS), distant metastasis-free survival (DMFS), and overall survival (OS) were 96.1%, 98.2%, 92.0%, and 86.3%, respectively, at 3 years. Cox multivariate regression analysis showed that age and T stage were independent predictors for 3-year OS. Conclusions. Helical tomotherapy for NPC patients achieved excellent 3-year locoregional control, distant metastasis-free survival, and overall survival, with relatively minor acute and late toxicities. Age and T stage were the main prognosis factors. PMID:25114932

An automatic dose verification system for adaptive radiotherapy for helical tomotherapy

NASA Astrophysics Data System (ADS)

Mo, Xiaohu; Chen, Mingli; Parnell, Donald; Olivera, Gustavo; Galmarini, Daniel; Lu, Weiguo

2014-03-01

Purpose: During a typical 5-7 week treatment of external beam radiotherapy, there are potential differences between planned patient's anatomy and positioning, such as patient weight loss, or treatment setup. The discrepancies between planned and delivered doses resulting from these differences could be significant, especially in IMRT where dose distributions tightly conforms to target volumes while avoiding organs-at-risk. We developed an automatic system to monitor delivered dose using daily imaging. Methods: For each treatment, a merged image is generated by registering the daily pre-treatment setup image and planning CT using treatment position information extracted from the Tomotherapy archive. The treatment dose is then computed on this merged image using our in-house convolution-superposition based dose calculator implemented on GPU. The deformation field between merged and planning CT is computed using the Morphon algorithm. The planning structures and treatment doses are subsequently warped for analysis and dose accumulation. All results are saved in DICOM format with private tags and organized in a database. Due to the overwhelming amount of information generated, a customizable tolerance system is used to flag potential treatment errors or significant anatomical changes. A web-based system and a DICOM-RT viewer were developed for reporting and reviewing the results. Results: More than 30 patients were analysed retrospectively. Our in-house dose calculator passed 97% gamma test evaluated with 2% dose difference and 2mm distance-to-agreement compared with Tomotherapy calculated dose, which is considered sufficient for adaptive radiotherapy purposes. Evaluation of the deformable registration through visual inspection showed acceptable and consistent results, except for cases with large or unrealistic deformation. Our automatic flagging system was able to catch significant patient setup errors or anatomical changes. Conclusions: We developed an automatic dose verification system that quantifies treatment doses, and provides necessary information for adaptive planning without impeding clinical workflows.

A virtual source model for Monte Carlo simulation of helical tomotherapy.

PubMed

Yuan, Jiankui; Rong, Yi; Chen, Quan

2015-01-08

The purpose of this study was to present a Monte Carlo (MC) simulation method based on a virtual source, jaw, and MLC model to calculate dose in patient for helical tomotherapy without the need of calculating phase-space files (PSFs). Current studies on the tomotherapy MC simulation adopt a full MC model, which includes extensive modeling of radiation source, primary and secondary jaws, and multileaf collimator (MLC). In the full MC model, PSFs need to be created at different scoring planes to facilitate the patient dose calculations. In the present work, the virtual source model (VSM) we established was based on the gold standard beam data of a tomotherapy unit, which can be exported from the treatment planning station (TPS). The TPS-generated sinograms were extracted from the archived patient XML (eXtensible Markup Language) files. The fluence map for the MC sampling was created by incorporating the percentage leaf open time (LOT) with leaf filter, jaw penumbra, and leaf latency contained from sinogram files. The VSM was validated for various geometry setups and clinical situations involving heterogeneous media and delivery quality assurance (DQA) cases. An agreement of < 1% was obtained between the measured and simulated results for percent depth doses (PDDs) and open beam profiles for all three jaw settings in the VSM commissioning. The accuracy of the VSM leaf filter model was verified in comparing the measured and simulated results for a Picket Fence pattern. An agreement of < 2% was achieved between the presented VSM and a published full MC model for heterogeneous phantoms. For complex clinical head and neck (HN) cases, the VSM-based MC simulation of DQA plans agreed with the film measurement with 98% of planar dose pixels passing on the 2%/2 mm gamma criteria. For patient treatment plans, results showed comparable dose-volume histograms (DVHs) for planning target volumes (PTVs) and organs at risk (OARs). Deviations observed in this study were consistent with literature. The VSM-based MC simulation approach can be feasibly built from the gold standard beam model of a tomotherapy unit. The accuracy of the VSM was validated against measurements in homogeneous media, as well as published full MC model in heterogeneous media.

A virtual source model for Monte Carlo simulation of helical tomotherapy

PubMed Central

Yuan, Jiankui; Rong, Yi

2015-01-01

The purpose of this study was to present a Monte Carlo (MC) simulation method based on a virtual source, jaw, and MLC model to calculate dose in patient for helical tomotherapy without the need of calculating phase‐space files (PSFs). Current studies on the tomotherapy MC simulation adopt a full MC model, which includes extensive modeling of radiation source, primary and secondary jaws, and multileaf collimator (MLC). In the full MC model, PSFs need to be created at different scoring planes to facilitate the patient dose calculations. In the present work, the virtual source model (VSM) we established was based on the gold standard beam data of a tomotherapy unit, which can be exported from the treatment planning station (TPS). The TPS‐generated sinograms were extracted from the archived patient XML (eXtensible Markup Language) files. The fluence map for the MC sampling was created by incorporating the percentage leaf open time (LOT) with leaf filter, jaw penumbra, and leaf latency contained from sinogram files. The VSM was validated for various geometry setups and clinical situations involving heterogeneous media and delivery quality assurance (DQA) cases. An agreement of <1% was obtained between the measured and simulated results for percent depth doses (PDDs) and open beam profiles for all three jaw settings in the VSM commissioning. The accuracy of the VSM leaf filter model was verified in comparing the measured and simulated results for a Picket Fence pattern. An agreement of <2% was achieved between the presented VSM and a published full MC model for heterogeneous phantoms. For complex clinical head and neck (HN) cases, the VSM‐based MC simulation of DQA plans agreed with the film measurement with 98% of planar dose pixels passing on the 2%/2 mm gamma criteria. For patient treatment plans, results showed comparable dose‐volume histograms (DVHs) for planning target volumes (PTVs) and organs at risk (OARs). Deviations observed in this study were consistent with literature. The VSM‐based MC simulation approach can be feasibly built from the gold standard beam model of a tomotherapy unit. The accuracy of the VSM was validated against measurements in homogeneous media, as well as published full MC model in heterogeneous media. PACS numbers: 87.53.‐j, 87.55.K‐ PMID:25679157

SU-E-T-91: Correction Method to Determine Surface Dose for OSL Detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reynolds, T; Higgins, P

Purpose: OSL detectors are commonly used in clinic due to their numerous advantages, such as linear response, negligible energy, angle and temperature dependence in clinical range, for verification of the doses beyond the dmax. Although, due to the bulky shielding envelope, this type of detectors fails to measure skin dose, which is an important assessment of patient ability to finish the treatment on time and possibility of acute side effects. This study aims to optimize the methodology of determination of skin dose for conventional accelerators and a flattening filter free Tomotherapy. Methods: Measurements were done for x-ray beams: 6 MVmore » (Varian Clinac 2300, 10×10 cm{sup 2} open field, SSD = 100 cm) and for 5.5 MV (Tomotherapy, 15×40 cm{sup 2} field, SAD = 85 cm). The detectors were placed at the surface of the solid water phantom and at the reference depth (dref=1.7cm (Varian 2300), dref =1.0 cm (Tomotherapy)). The measurements for OSLs were related to the externally exposed OSLs measurements, and further were corrected to surface dose using an extrapolation method indexed to the baseline Attix ion chamber measurements. A consistent use of the extrapolation method involved: 1) irradiation of three OSLs stacked on top of each other on the surface of the phantom; 2) measurement of the relative dose value for each layer; and, 3) extrapolation of these values to zero thickness. Results: OSL measurements showed an overestimation of surface doses by the factor 2.31 for Varian 2300 and 2.65 for Tomotherapy. The relationships: SD{sup 2300} = 0.68 × M{sup 2300}-12.7 and SDτoμo = 0.73 × Mτoμo-13.1 were found to correct the single OSL measurements to surface doses in agreement with Attix measurements to within 0.1% for both machines. Conclusion: This work provides simple empirical relationships for surface dose measurements using single OSL detectors.« less

Comparing the quality of passively-scattered proton and photon tomotherapy plans for brain and head and neck disease sites.

PubMed

Kainz, Kristofer; Firat, Selim; Wilson, J Frank; Schultz, Christopher; Siker, Malika; Wang, Andrew; Olson, Dan; Li, X Allen

2015-03-21

We compare the quality of photon IMRT (helical tomotherapy) with classic proton plans for brain, head and neck tumors, in terms of target dose uniformity and conformity along with organ-at-risk (OAR) sparing. Plans were created for twelve target volumes among eight cases. All patients were originally planned and treated using helical tomotherapy. Proton plans were generated using a passively-scattered beam model with a maximum range of 32 g cm(-2) (225 MeV), range modulation in 0.5 g cm(-2) increments and range compensators with 4.8 mm milling tool diameters. All proton plans were limited to two to four beams. Plan quality was compared using uniformity index (UI), conformation number (CN) and a EUD-based plan quality index (fEUD). For 11 of the 12 targets, UI was improved for the proton plan; on average, UI was 1.05 for protons versus 1.08 for tomotherapy. For 7 of the 12 targets, the tomotherapy plan exhibited more favorable CN. For proximal OARs, the improved dose conformity to the target volume from tomotherapy led to a lower maximum dose. For distal OARs, the maximum dose was much lower for proton plans. For 6 of the 8 cases, near-total avoidance for distal OARs provided by protons leads to improved fEUD. However, if distal OARs are excluded in the fEUD calculation, the proton plans exhibit better fEUD in only 3 of the 8 cases. The distal OAR sparing and target dose uniformity are generally better with passive-scatter proton planning than with photon tomotherapy; proton therapy may be preferred if the clinician deems those attributes critical. However, tomotherapy may serve equally as well as protons for cases where superior target dose conformity from tomotherapy leads to plan quality nearly identical to or better than protons and for cases where distal OAR sparing is not concerning.

Feasibility of tomotherapy to reduce normal lung and cardiac toxicity for distal esophageal cancer compared to three-dimensional radiotherapy.

PubMed

Nguyen, Nam P; Krafft, Shane P; Vinh-Hung, Vincent; Vos, Paul; Almeida, Fabio; Jang, Siyoung; Ceizyk, Misty; Desai, Anand; Davis, Rick; Hamilton, Russ; Modarresifar, Homayoun; Abraham, Dave; Smith-Raymond, Lexie

2011-12-01

To compare the effectiveness of tomotherapy and three-dimensional (3D) conformal radiotherapy to spare normal critical structures (spinal cord, lungs, and ventricles) from excessive radiation in patients with distal esophageal cancers. A retrospective dosimetric study of nine patients who had advanced gastro-esophageal (GE) junction cancer (7) or thoracic esophageal cancer (2) extending into the distal esophagus. Two plans were created for each of the patients. A three-dimensional plan was constructed with either three (anteroposterior, right posterior oblique, and left posterior oblique) or four (right anterior oblique, left anterior oblique, right posterior oblique, and left posterior oblique) fields. The second plan was for tomotherapy. Doses were 45 Gy to the PTV with an integrated boost of 5 Gy for tomotherapy. Mean lung dose was respectively 7.4 and 11.8 Gy (p=0.004) for tomotherapy and 3D plans. Corresponding values were 12.4 and 18.3 Gy (p=0.006) for cardiac ventricles. Maximum spinal cord dose was respectively 31.3 and 37.4 Gy (p < 0.007) for tomotherapy and 3D plans. Homogeneity index was two for both groups. Compared to 3D conformal radiotherapy, tomotherapy decreased significantly the amount of normal tissue irradiated and may reduce treatment toxicity for possible dose escalation in future prospective studies. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

A multi-institutional dosimetry audit of rotational intensity-modulated radiotherapy.

PubMed

Clark, Catharine H; Hussein, Mohammad; Tsang, Yatman; Thomas, Russell; Wilkinson, Dean; Bass, Graham; Snaith, Julia; Gouldstone, Clare; Bolton, Steve; Nutbrown, Rebecca; Venables, Karen; Nisbet, Andrew

2014-11-01

Rotational IMRT (VMAT and Tomotherapy) has now been implemented in many radiotherapy centres. An audit to verify treatment planning system modelling and treatment delivery has been undertaken to ensure accurate clinical implementation. 34 institutions with 43 treatment delivery systems took part in the audit. A virtual phantom planning exercise (3DTPS test) and a clinical trial planning exercise were planned and independently measured in each institution using a phantom and array combination. Point dose differences and global gamma index (γ) were calculated in regions corresponding to PTVs and OARs. Point dose differences gave a mean (±sd) of 0.1±2.6% and 0.2±2.0% for the 3DTPS test and clinical trial plans, respectively. 34/43 planning and delivery combinations achieved all measured planes with >95% pixels passing γ<1 at 3%/3mm and rose to 42/43 for clinical trial plans. A statistically significant difference in γ pass rates (p<0.01) was seen between planning systems where rotational IMRT modelling had been designed for the manufacturer's own treatment delivery system and those designed independently of rotational IMRT delivery. A dosimetry audit of rotational radiotherapy has shown that TPS modelling and delivery for rotational IMRT can achieve high accuracy of plan delivery. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Donovan, Ellen M., E-mail: ellen.donovan@icr.ac.u; Ciurlionis, Laura; Fairfoul, Jamie

Purpose: To establish planning solutions for a concomitant three-level radiation dose distribution to the breast using linear accelerator- or tomotherapy-based intensity-modulated radiotherapy (IMRT), for the U.K. Intensity Modulated and Partial Organ (IMPORT) High trial. Methods and Materials: Computed tomography data sets for 9 patients undergoing breast conservation surgery with implanted tumor bed gold markers were used to prepare three-level dose distributions encompassing the whole breast (36 Gy), partial breast (40 Gy), and tumor bed boost (48 or 53 Gy) treated concomitantly in 15 fractions within 3 weeks. Forward and inverse planned IMRT and tomotherapy were investigated as solutions. A standardmore » electron field was compared with a photon field arrangement encompassing the tumor bed boost volume. The out-of-field doses were measured for all methods. Results: Dose-volume constraints of volume >90% receiving 32.4 Gy and volume >95% receiving 50.4 Gy for the whole breast and tumor bed were achieved. The constraint of volume >90% receiving 36 Gy for the partial breast was fulfilled in the inverse IMRT and tomotherapy plans and in 7 of 9 cases of a forward planned IMRT distribution. An electron boost to the tumor bed was inadequate in 8 of 9 cases. The IMRT methods delivered a greater whole body dose than the standard breast tangents. A contralateral lung volume >2.5 Gy was increased in the inverse IMRT and tomotherapy plans, although it did not exceed the constraint. Conclusion: We have demonstrated a set of widely applicable solutions that fulfilled the stringent clinical trial requirements for the delivery of a concomitant three-level dose distribution to the breast.« less

Schedule for CT image guidance in treating prostate cancer with helical tomotherapy

PubMed Central

Beldjoudi, G; Yartsev, S; Bauman, G; Battista, J; Van Dyk, J

2010-01-01

The aim of this study was to determine the effect of reducing the number of image guidance sessions and patient-specific target margins on the dose distribution in the treatment of prostate cancer with helical tomotherapy. 20 patients with prostate cancer who were treated with helical tomotherapy using daily megavoltage CT (MVCT) imaging before treatment served as the study population. The average geometric shifts applied for set-up corrections, as a result of co-registration of MVCT and planning kilovoltage CT studies over an increasing number of image guidance sessions, were determined. Simulation of the consequences of various imaging scenarios on the dose distribution was performed for two patients with different patterns of interfraction changes in anatomy. Our analysis of the daily set-up correction shifts for 20 prostate cancer patients suggests that the use of four fractions would result in a population average shift that was within 1 mm of the average obtained from the data accumulated over all daily MVCT sessions. Simulation of a scenario in which imaging sessions are performed at a reduced frequency and the planning target volume margin is adapted provided significantly better sparing of organs at risk, with acceptable reproducibility of dose delivery to the clinical target volume. Our results indicate that four MVCT sessions on helical tomotherapy are sufficient to provide information for the creation of personalised target margins and the establishment of the new reference position that accounts for the systematic error. This simplified approach reduces overall treatment session time and decreases the imaging dose to the patient. PMID:19505966

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lian, Jun, E-mail: jun-lian@med.unc.edu; Chera, Bhishamjit S.; Chang, Sha

Purpose: To build a statistical model to quantitatively correlate the anatomic features of structures and the corresponding dose-volume histogram (DVH) of head and neck (HN) Tomotherapy (Tomo) plans. To study if the model built upon one intensity modulated radiation therapy (IMRT) technique (such as conventional Linac) can be used to predict anticipated organs-at-risk (OAR) DVH of patients treated with a different IMRT technique (such as Tomo). To study if the model built upon the clinical experience of one institution can be used to aid IMRT planning for another institution. Methods: Forty-four Tomotherapy intensity modulate radiotherapy plans of HN cases (Tomo-IMRT)more » from Institution A were included in the study. A different patient group of 53 HN fixed gantry IMRT (FG-IMRT) plans was selected from Institution B. The analyzed OARs included the parotid, larynx, spinal cord, brainstem, and submandibular gland. Two major groups of anatomical features were considered: the volumetric information and the spatial information. The volume information includes the volume of target, OAR, and overlapped volume between target and OAR. The spatial information of OARs relative to PTVs was represented by the distance-to-target histogram (DTH). Important anatomical and dosimetric features were extracted from DTH and DVH by principal component analysis. Two regression models, one for Tomotherapy plan and one for IMRT plan, were built independently. The accuracy of intratreatment-modality model prediction was validated by a leave one out cross-validation method. The intertechnique and interinstitution validations were performed by using the FG-IMRT model to predict the OAR dosimetry of Tomo-IMRT plans. The dosimetry of OARs, under the same and different institutional preferences, was analyzed to examine the correlation between the model prediction and planning protocol. Results: Significant patient anatomical factors contributing to OAR dose sparing in HN Tomotherapy plans have been analyzed and identified. For all the OARs, the discrepancies of dose indices between the model predicted values and the actual plan values were within 2.1%. Similar results were obtained from the modeling of FG-IMRT plans. The parotid gland was spared in a comparable fashion during the treatment planning of two institutions. The model based on FG-IMRT plans was found to predict the median dose of the parotid of Tomotherapy plans quite well, with a mean error of 2.6%. Predictions from the FG-IMRT model suggested the median dose of the larynx, median dose of the brainstem and D2 of the brainstem could be reduced by 10.5%, 12.8%, and 20.4%, respectively, in the Tomo-IMRT plans. This was found to be correlated to the institutional differences in OAR constraint settings. Re-planning of six Tomotherapy patients confirmed the potential of optimization improvement predicted by the FG-IMRT model was correct. Conclusions: The authors established a mathematical model to correlate the anatomical features and dosimetric indexes of OARs of HN patients in Tomotherapy plans. The model can be used for the setup of patient-specific OAR dose sparing goals and quality control of planning results. The institutional clinical experience was incorporated into the model which allows the model from one institution to generate a reference plan for another institution, or another IMRT technique.« less

Locoregional Control and Toxicity in Head and Neck Carcinoma Patients following Helical Tomotherapy-Delivered Intensity-Modulated Radiation Therapy Compared with 3D-CRT Data.

PubMed

Santa Cruz, Olalla; Tsoutsou, Pelagia; Castella, Cyril; Khanfir, Kaouthar; Anchisi, Sandro; Bouayed, Salim; Matzinger, Oscar; Ozsahin, Mahmut

2018-06-12

To assess the feasibility and efficacy of intensity-modulated radiation implemented with helical tomotherapy image-guided with daily megavoltage computed tomography for head and neck cancer. Between May 2010 and May 2013, 72 patients were treated with curative intent. The median age was 64 years, with 57% undergoing definitive and 43% postoperative radiotherapy. Primary tumour sites were oral cavity (21%), oropharynx (26%), hypopharynx (20%), larynx (22%), and others (11%). Staging included 4% stage I, 15% II, 26% III, 48% IVa, and 7% IVb. Radiotherapy was combined with chemotherapy in 64%. Primary endpoint was locoregional control, and secondary endpoints survival and toxicity. Median follow-up was 20 months, with 11 locoregional recurrences. Three-year disease-free survival was 58% and overall survival 57%. In the multivariate analysis, age under 64 years, no extracapsular extension, postoperative radiotherapy, induction chemotherapy, and non-oral cavity tumour were significant favourable prognostic factors for disease-free-survival. The overall incidence of acute grade ≥3 toxicities were mucositis 32%, pain 11%, xerostomia 7%, dysphagia 53%, radiodermatitis 44%, and osteonecrosis 1%. Late grade ≥3 toxicities were fibrosis 6%, dysphagia 21%, fistula 1%, and skin necrosis 1%. Intensity-modulated radiation with helical tomotherapy achieved respectable locoregional control and overall survival, with acceptable toxicity, in head and neck cancer patients. © 2018 S. Karger AG, Basel.

Clinical applications of image guided-intensity modulated radiation therapy (IG-IMRT) for conformal avoidance of normal tissue

NASA Astrophysics Data System (ADS)

Gutierrez, Alonso Navar

2007-12-01

Recent improvements in imaging technology and radiation delivery have led to the development of advanced treatment techniques in radiotherapy which have opened the door for novel therapeutic approaches to improve the efficacy of radiation cancer treatments. Among these advances is image-guided, intensity modulated radiation therapy (IG-IMRT), in which imaging is incorporated to aid in inter-/intra-fractional target localization and to ensure accurate delivery of precise and highly conformal dose distributions. In principle, clinical implementation of IG-IMRT should improve normal tissue sparing and permit effective biological dose escalation thus widening the radiation therapeutic window and lead to increases in survival through improved local control of primary neoplastic diseases. Details of the development of three clinical applications made possible solely with IG-IMRT radiation delivery techniques are presented: (1) Laparoscopically implanted tissue expander radiotherapy (LITE-RT) has been developed to enhance conformal avoidance of normal tissue during the treatment of intra-abdominopelvic cancers. LITE-RT functions by geometrically displacing surrounding normal tissue and isolating the target volume through the interfractional inflation of a custom-shaped tissue expander throughout the course of treatment. (2) The unique delivery geometry of helical tomotherapy, a novel form of IG-IMRT, enables the delivery of composite treatment plan m which whole brain radiotherapy (WBRT) with hippocampal avoidance, hypothesized to reduce the risk of memory function decline and improve the patient's quality of life, and simultaneously integrated boost to multiple brain metastases to improve intracranial tumor control is achieved. (3) Escalation of biological dose to targets through integrated, selective subvolume boosts have been shown to efficiently increase tumor dose without significantly increasing normal tissue dose. Helical tomotherapy was used to investigate the feasibility of delivering a simultaneously integrated subvolume boost to canine nasal tumors and was found to dramatically increase estimated 1-year tumor control probability (TCP) without increasing the dose to the eyes, so as to preserve vision, and to the brain, so as to prevent neuropathy.

Clinical observation of 73 nasopharyngeal carcinoma patients treated by helical tomotherapy: the China experience.

PubMed

Ren, G; Du, L; Ma, L; Feng, L-C; Zhou, G-X; Qu, B-L; Xu, S-P; Xie, C-B; Ou, G-M; Li, F; Zhang, X-X; Yang, J

2011-06-01

The preliminary short-term clinical outcome of 73 nasopharyngeal carcinoma (NPC) patients treated with helical tomotherapy at our cancer institute has been evaluated. Between September 2007 and September 2009, 73 newly diagnosed NPC patients were treated with helical tomotherapy. The distributions of clinical stages according to the UICC 2002 Staging System were: 6, 27, 24, and 16 for Stage I, IIa-b, III, and IVa-b, respectively. The prescription dose was 70-74 Gy/33F to planning gross tumor volume containing the primary tumor and positive lymph nodes, with 60-62.7 Gy/33F to high risk planning target volume, while delivering 52-56 Gy/33F to low risk planning target volume. Twenty-four patients were treated with radiation therapy as single modality, 25 with concurrent cisplatin-based chemotherapy with or without anti-EGFR monoclonal antibody therapy, and 24 with concurrent anti-EGFR monoclonal antibody therapy. Setup errors were analyzed. Side-effects were evaluated with the established RTOG/EORTC criteria. Average beam-on-time was 468.8 sec/F (396.7-696.1 sec). The setup errors in the lateral, longitudinal and vertical directions were 0.00 ± 1.79 mm, -0.55± 2.17 mm and 0.38 ± 1.43 mm, corresponding to 3.80 mm, 4.20 mm, and 2.46 mm as the CTV-PTV margin in these directions. The grade 0, 1, 2 and 3 acute skin toxicity was 2.7%, 76.7%, 13.8% and 6.8%; the grade 0, 1, 2 and 3 acute mucositis was 1.4%, 32.9%, 60.2% and 5.5%; and the grade 0, 1, 2 and 3 acute xerostomia was 4.0%, 45.3%, 50.7% and 0, respectively. Only 5 patients suffered from grade 3 or 4 leucopenia. Xerostomia resolved with passing of time and no grade 2 or more xerostomia was noted one year after radiation therapy. Concurrent chemotherapy significantly increased incidence of severe acute toxicities. One month after radiation therapy the remission rates of primary tumor and positive lymph nodes were 91.8% and 98.1%, respectively. The median follow-up was 14.8 months. The one-year relapse-free survival, distant metastasis-free survival and overall survival was 95.6%, 97.2% and 94.8%, respectively. In conclusion, the incidence of severe acute toxicities and late xerostomia was relatively infrequent for NPC patients treated with helical tomotherapy. The long-term clinical outcome for these patients is under investigation.

Image-guided total marrow and total lymphatic irradiation using helical tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schultheiss, Timothy E.; Wong, Jeffrey; Liu, An

2007-03-15

Purpose: To develop a treatment technique to spare normal tissue and allow dose escalation in total body irradiation (TBI). We have developed intensity-modulated radiotherapy techniques for the total marrow irradiation (TMI), total lymphatic irradiation, or total bone marrow plus lymphatic irradiation using helical tomotherapy. Methods and Materials: For TBI, we typically use 12 Gy in 10 fractions delivered at an extended source-to-surface distance (SSD). Using helical tomotherapy, it is possible to deliver equally effective doses to the bone marrow and lymphatics while sparing normal organs to a significant degree. In the TMI patients, whole body skeletal bone, including the ribsmore » and sternum, comprise the treatment target. In the total lymphatic irradiation, the target is expanded to include the spleen and major lymph node areas. Sanctuary sites for disease (brain and testes) are included when clinically indicated. Spared organs include the lungs, esophagus, parotid glands, eyes, oral cavity, liver, kidneys, stomach, small and large intestine, bladder, and ovaries. Results: With TBI, all normal organs received the TBI dose; with TMI, total lymphatic irradiation, and total bone marrow plus lymphatic irradiation, the visceral organs are spared. For the first 6 patients treated with TMI, the median dose to organs at risk averaged 51% lower than would be achieved with TBI. By putting greater weight on the avoidance of specific organs, greater sparing was possible. Conclusion: Sparing of normal tissues and dose escalation is possible using helical tomotherapy. Late effects such as radiation pneumonitis, veno-occlusive disease, cataracts, neurocognitive effects, and the development of second tumors should be diminished in severity and frequency according to the dose reduction realized for the organs at risk.« less

Concurrent Chemoradiotherapy With Helical Tomotherapy for Oropharyngeal Cancer: A Preliminary Result

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shueng, Pei-Wei; Department of Radiation Oncology, National Defense Medical Center, Taipei, Taiwan; General Education Center, Oriental Technology Institute, Taipei, Taiwan

Purpose: To review the experience with and evaluate the treatment plan for helical tomotherapy for the treatment of oropharyngeal cancer. Methods and Materials: Between November 1, 2006 and January 31, 2009, 10 histologically confirmed oropharyngeal cancer patients were enrolled. All patients received definitive concurrent chemoradiation with helical tomotherapy. The prescription dose to the gross tumor planning target volume, the high-risk subclinical area, and the low-risk subclinical area was 70Gy, 63Gy, and 56Gy, respectively. During radiotherapy, all patients were treated with cisplatin, 30mg/m{sup 2}, plus 5-fluorouracil (425mg/m{sup 2})/leucovorin (30mg/m{sup 2}) intravenously weekly. Toxicity of treatment was scored according to the Commonmore » Terminology Criteria for Adverse Events, version 3.0. Several parameters, including maximal or median dose to critical organs, uniformity index, and conformal index, were evaluated from dose-volume histograms. Results: The mean survival was 18 months (range, 7-22 months). The actuarial overall survival, disease-free survival, locoregional control, and distant metastasis-free rates at 18 months were 67%, 70%, 80%, and 100%, respectively. The average for uniformity index and conformal index was 1.05 and 1.26, respectively. The mean of median dose for right side and left side parotid glands was 23.5 and 23.9Gy, respectively. No Grade 3 toxicity for dermatitis and body weight loss and only one instance of Grade 3 mucositis were noted. Conclusion: Helical tomotherapy achieved encouraging clinical outcomes in patients with oropharyngeal carcinoma. Treatment toxicity was acceptable, even in the setting of concurrent chemotherapy. Long-term follow-up is needed to confirm these preliminary findings.« less

TomoTherapy MLC verification using exit detector data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Quan; Westerly, David; Fang Zhenyu

2012-01-15

Purpose: Treatment delivery verification (DV) is important in the field of intensity modulated radiation therapy (IMRT). While IMRT and image guided radiation therapy (IGRT), allow us to create more conformal plans and enables the use of tighter margins, an erroneously executed plan can have detrimental effects on the treatment outcome. The purpose of this study is to develop a DV technique to verify TomoTherapy's multileaf collimator (MLC) using the onboard mega-voltage CT detectors. Methods: The proposed DV method uses temporal changes in the MVCT detector signal to predict actual leaf open times delivered on the treatment machine. Penumbra and scatteredmore » radiation effects may produce confounding results when determining leaf open times from the raw detector data. To reduce the impact of the effects, an iterative, Richardson-Lucy (R-L) deconvolution algorithm is applied. Optical sensors installed on each MLC leaf are used to verify the accuracy of the DV technique. The robustness of the DV technique is examined by introducing different attenuation materials in the beam. Additionally, the DV technique has been used to investigate several clinical plans which failed to pass delivery quality assurance (DQA) and was successful in identifying MLC timing discrepancies as the root cause. Results: The leaf open time extracted from the exit detector showed good agreement with the optical sensors under a variety of conditions. Detector-measured leaf open times agreed with optical sensor data to within 0.2 ms, and 99% of the results agreed within 8.5 ms. These results changed little when attenuation was added in the beam. For the clinical plans failing DQA, the dose calculated from reconstructed leaf open times played an instrumental role in discovering the root-cause of the problem. Throughout the retrospective study, it is found that the reconstructed dose always agrees with measured doses to within 1%. Conclusions: The exit detectors in the TomoTherapy treatment systems can provide valuable information about MLC behavior during delivery. A technique to estimate the TomoTherapy binary MLC leaf open time from exit detector signals is described. This technique is shown to be both robust and accurate for delivery verification.« less

SU-F-BRD-02: Application of ARCHERRT-- A GPU-Based Monte Carlo Dose Engine for Radiation Therapy -- to Tomotherapy and Patient-Independent IMRT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, L; Du, X; Liu, T

Purpose: As a module of ARCHER -- Accelerated Radiation-transport Computations in Heterogeneous EnviRonments, ARCHER{sub RT} is designed for RadioTherapy (RT) dose calculation. This paper describes the application of ARCHERRT on patient-dependent TomoTherapy and patient-independent IMRT. It also conducts a 'fair' comparison of different GPUs and multicore CPU. Methods: The source input used for patient-dependent TomoTherapy is phase space file (PSF) generated from optimized plan. For patient-independent IMRT, the open filed PSF is used for different cases. The intensity modulation is simulated by fluence map. The GEANT4 code is used as benchmark. DVH and gamma index test are employed to evaluatemore » the accuracy of ARCHER{sub RT} code. Some previous studies reported misleading speedups by comparing GPU code with serial CPU code. To perform a fairer comparison, we write multi-thread code with OpenMP to fully exploit computing potential of CPU. The hardware involved in this study are a 6-core Intel E5-2620 CPU and 6 NVIDIA M2090 GPUs, a K20 GPU and a K40 GPU. Results: Dosimetric results from ARCHER{sub RT} and GEANT4 show good agreement. The 2%/2mm gamma test pass rates for different clinical cases are 97.2% to 99.7%. A single M2090 GPU needs 50~79 seconds for the simulation to achieve a statistical error of 1% in the PTV. The K40 card is about 1.7∼1.8 times faster than M2090 card. Using 6 M2090 card, the simulation can be finished in about 10 seconds. For comparison, Intel E5-2620 needs 507∼879 seconds for the same simulation. Conclusion: We successfully applied ARCHER{sub RT} to Tomotherapy and patient-independent IMRT, and conducted a fair comparison between GPU and CPU performance. The ARCHER{sub RT} code is both accurate and efficient and may be used towards clinical applications.« less

SU-F-P-11: Long Term Dosimetric Stability of 6 TomoTherapy Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smilowitz, J; Dunkerley, D; Geurts, M

2016-06-15

Purpose: The dosimetric stability of six TomoTherapy units was analyzed to investigate changes in performance over time and with system upgrades. Methods: Energy and output were tracked using monitor chamber signal, onboard MVCT detector signal and external ion chamber measurements. The systems (and monitoring periods) include 3 Hi-Art (67, 61 and 65 mos.), 2 HDA (29 and 25 mos.) and one research unit (7 mo.). Dose Control Stability system (DCS) was installed on 4 systems. Output stability is reported as deviation from reference monitor chamber signal for all systems, and from an external chamber for 4 systems. Energy stability wasmore » monitored using the relative (center versus off-axis) MVCT detector signal and/or the ratio of chamber measurements at 2 depths. The results from the clinical systems were used to benchmark the stability of the research unit, which has the same linear accelerator but runs at a higher dose rate. Results: The output based on monitor chamber data of all six systems is very stable. Non- DCS had a standard deviation of 1.7% and 1.8%. As expected, DCS systems had improved standard deviation: 0.003–0.05%. The energy was also very stable for all units. The standard deviation in exit detector flatness was 0.02–0.3%. Ion chamber output and 20/10 cm ratios supported these results. The stability for the research system, as monitored with a variety of metrics, is on par with the existing systems. Conclusion: The output and energy of six TomoTherapy units over a total of almost 10 years is quite stable. For each system, the results are consistent between the different measurement tools and techniques, proving not only the dosimetric stability, but that these quality parameters can be confirmed with various metrics. A research unit operating at a higher dose rate performed as well as the clinical treatment units. University of Wisconsin and Accuray Inc. (vendor of TomoTherapy systems) have a research agreement which supplies funds for research to the University. This project was partially supporting with these funds.« less

Evaluation of radiosurgery techniques–Cone-based linac radiosurgery vs tomotherapy-based radiosurgery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yip, Ho Yin, E-mail: hoyinyip@yahoo.com.hk; Mui, Wing Lun A.; Lee, Joseph W.Y.

2013-07-01

Performances of radiosurgery of intracranial lesions between cone-based Linac system and Tomotherapy-based system were compared in terms of dosimetry and time. Twelve patients with single intracranial lesion treated with cone-based Linac radiosurgery system from 2005 to 2009 were replanned for Tomotherapy-based radiosurgery treatment. The conformity index, homogeneity index (HI), and gradient score index (GSI) of each case was calculated. The Wilcoxon matched-pair test was used to compare the 3 indices between both systems. The cases with regular target (n = 6) and those with irregular target (n = 6) were further analyzed separately. The estimated treatment time between both systemsmore » was also compared. Significant differences were found in HI (p = 0.05) and in GSI (p = 0.03) for the whole group. Cone-based radiosurgery was better in GSI whereas Tomotherapy-based radiosurgery was better in HI. Cone-based radiosurgery was better in conformity index (p = 0.03) and GSI (p = 0.03) for regular targets, whereas Tomotherapy-based radiosurgery system performed significantly better in HI (p = 0.03) for irregular targets. The estimated total treatment time for Tomotherapy-based radiosurgery ranged from 24 minutes to 35 minutes, including 15 minutes of pretreatment megavoltage computed tomography (MVCT) and image registration, whereas that for cone-based radiosurgery ranged from 15 minutes for 1 isocenter to 75 minutes for 5 isocenters. As a rule of thumb, Tomotherapy-based radiosurgery system should be the first-line treatment for irregular lesions because of better dose homogeneity and shorter treatment time. Cone-based Linac radiosurgery system should be the treatment of choice for regular targets because of the better dose conformity, rapid dose fall-off, and reasonable treatment time.« less

Standard and Nonstandard Craniospinal Radiotherapy Using Helical TomoTherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, William, E-mail: william@medphys.mcgill.c; Brodeur, Marylene; Roberge, David

2010-07-01

Purpose: To show the advantages of planning and delivering craniospinal radiotherapy with helical TomoTherapy (TomoTherapy Inc., Madison, WI) by presenting 4 cases treated at our institution. Methods and Materials: We first present a standard case of craniospinal irradiation in a patient with recurrent myxopapillary ependymoma (MPE) and follow this with 2 cases requiring differential dosing to multiple target volumes. One of these, a patient with recurrent medulloblastoma, required a lower dose to be delivered to the posterior fossa because the patient had been previously irradiated to the full dose, and the other required concurrent boosts to leptomeningeal metastases as partmore » of his treatment for newly diagnosed MPE. The final case presented is a patient with pronounced scoliosis who required spinal irradiation for recurrent MPE. Results: The four cases presented were planned and treated successfully with Helical Tomotherapy. Conclusions: Helical TomoTherapy delivers continuous arc-based intensity-modulated radiotherapy that gives high conformality and excellent dose homogeneity for the target volumes. Increased healthy tissue sparing is achieved at higher doses albeit at the expense of larger volumes of tissue receiving lower doses. Helical TomoTherapy allows for differential dosing of multiple targets, resulting in very elegant dose distributions. Daily megavoltage computed tomography imaging allows for precision of patient positioning, permitting a reduction in planning margins and increased healthy tissue sparing in comparison with standard techniques.« less

Modeling of Radiotherapy Linac Source Terms Using ARCHER Monte Carlo Code: Performance Comparison for GPU and MIC Parallel Computing Devices

NASA Astrophysics Data System (ADS)

Lin, Hui; Liu, Tianyu; Su, Lin; Bednarz, Bryan; Caracappa, Peter; Xu, X. George

2017-09-01

Monte Carlo (MC) simulation is well recognized as the most accurate method for radiation dose calculations. For radiotherapy applications, accurate modelling of the source term, i.e. the clinical linear accelerator is critical to the simulation. The purpose of this paper is to perform source modelling and examine the accuracy and performance of the models on Intel Many Integrated Core coprocessors (aka Xeon Phi) and Nvidia GPU using ARCHER and explore the potential optimization methods. Phase Space-based source modelling for has been implemented. Good agreements were found in a tomotherapy prostate patient case and a TrueBeam breast case. From the aspect of performance, the whole simulation for prostate plan and breast plan cost about 173s and 73s with 1% statistical error.

Treatment plan comparison between helical tomotherapy and MLC-based IMRT using radiobiological measures

NASA Astrophysics Data System (ADS)

Mavroidis, Panayiotis; Costa Ferreira, Brigida; Shi, Chengyu; Lind, Bengt K.; Papanikolaou, Nikos

2007-07-01

The rapid implementation of advanced treatment planning and delivery technologies for radiation therapy has brought new challenges in evaluating the most effective treatment modality. Intensity-modulated radiotherapy (IMRT) using multi-leaf collimators (MLC) and helical tomotherapy (HT) are becoming popular modes of treatment delivery and their application and effectiveness continues to be investigated. Presently, there are several treatment planning systems (TPS) that can generate and optimize IMRT plans based on user-defined objective functions for the internal target volume (ITV) and organs at risk (OAR). However, the radiobiological parameters of the different tumours and normal tissues are typically not taken into account during dose prescription and optimization of a treatment plan or during plan evaluation. The suitability of a treatment plan is typically decided based on dosimetric criteria such as dose-volume histograms (DVH), maximum, minimum, mean and standard deviation of the dose distribution. For a more comprehensive treatment plan evaluation, the biologically effective uniform dose ({\\bar{\\bar{D}}}) is applied together with the complication-free tumour control probability (P+). Its utilization is demonstrated using three clinical cases that were planned with two different forms of IMRT. In this study, three different cancer types at different anatomical sites were investigated: head and neck, lung and prostate cancers. For each cancer type, a linac MLC-based step-and-shoot IMRT plan and a HT plan were developed. The MLC-based IMRT treatment plans were developed on the Philips treatment-planning platform, using the Pinnacle 7.6 software release. For the tomotherapy HiArt plans, the dedicated tomotherapy treatment planning station was used, running version 2.1.2. By using {\\bar{\\bar{D}}} as the common prescription point of the treatment plans and plotting the tissue response probabilities versus {\\bar{\\bar{D}}} for a range of prescription doses, a number of plan trials can be compared based on radiobiological measures. The applied plan evaluation method shows that in the head and neck cancer case the HT treatment gives better results than MLC-based IMRT in terms of expected clinical outcome (P+ of 62.2% and 46.0%, {\\bar{\\bar{D}}} to the ITV of 72.3 Gy and 70.7 Gy, respectively). In the lung cancer and prostate cancer cases, the MLC-based IMRT plans are better over the clinically useful dose prescription range. For the lung cancer case, the HT and MLC-based IMRT plans give a P+ of 66.9% and 72.9%, {\\bar{\\bar{D}}} to the ITV of 64.0 Gy and 66.9 Gy, respectively. Similarly, for the prostate cancer case, the two radiation modalities give a P+ of 68.7% and 72.2%, {\\bar{\\bar{D}}} to the ITV of 86.0 Gy and 85.9 Gy, respectively. If a higher risk of complications (higher than 5%) could be allowed, the complication-free tumour control could increase by over 40%, 2% and 30% compared to the initial dose prescription for the three cancer cases, respectively. Both MLC-based IMRT and HT can encompass the often-large ITV required while they minimize the volume of the organs at risk receiving high doses. Radiobiological evaluation of treatment plans may provide an improved correlation of the delivered treatment with the clinical outcome by taking into account the dose-response characteristics of the irradiated targets and normal tissues. There may exist clinical cases, which may look dosimetrically similar but in radiobiological terms may be quite different. In such situations, traditional dose-based evaluation tools can be complemented by the use of P_ +{-}{\\bar{\\bar{D}}} diagrams to effectively evaluate and compare treatment plans.

SIS epidemiological model for adaptive RT: Forecasting the parotid glands shrinkage during tomotherapy treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maffei, Nicola; Guidi, Gabriele, E-mail: guidi.gab

Purpose: A susceptible-infected-susceptible (SIS) epidemic model was applied to radiation therapy (RT) treatments to predict morphological variations in head and neck (H&N) anatomy. Methods: 360 daily MVCT images of 12 H&N patients treated by tomotherapy were analyzed in this retrospective study. Deformable image registration (DIR) algorithms, mesh grids, and structure recontouring, implemented in the RayStation treatment planning system (TPS), were applied to assess the daily organ warping. The parotid’s warping was evaluated using the epidemiological approach considering each vertex as a single subject and its deformed vector field (DVF) as an infection. Dedicated IronPython scripts were developed to export dailymore » coordinates and displacements of the region of interest (ROI) from the TPS. MATLAB tools were implemented to simulate the SIS modeling. Finally, the fully trained model was applied to a new patient. Results: A QUASAR phantom was used to validate the model. The patients’ validation was obtained setting 0.4 cm of vertex displacement as threshold and splitting susceptible (S) and infectious (I) cases. The correlation between the epidemiological model and the parotids’ trend for further optimization of alpha and beta was carried out by Euclidean and dynamic time warping (DTW) distances. The best fit with experimental conditions across all patients (Euclidean distance of 4.09 ± 1.12 and DTW distance of 2.39 ± 0.66) was obtained setting the contact rate at 7.55 ± 0.69 and the recovery rate at 2.45 ± 0.26; birth rate was disregarded in this constant population. Conclusions: Combining an epidemiological model with adaptive RT (ART), the authors’ novel approach could support image-guided radiation therapy (IGRT) to validate daily setup and to forecast anatomical variations. The SIS-ART model developed could support clinical decisions in order to optimize timing of replanning achieving personalized treatments.« less

Clinical and technical feasibility of ultra-boost irradiation in Dominant Intraprostatic Lesion by Tomotherapy: preliminary experience and revision of literature.

PubMed

Garibaldi, Elisabetta; Delmastro, Elena; Gabriele, Domenico; Bresciani, Sara; Russo, Filippo; Di Dia, Amalia; Cattari, Gaetano; Belli, Gabriella; Gabriele, Pietro

2016-03-01

The aim of this paper was to present our experience of dominant intraprostatic lesions (DIL) irradiation up to an EQD2 of 93,2 Gy with helical tomotherapy. Between March 2012 and December 2014, 15 staged II-III patients with intermediate-high risk prostate cancer were enrolled in our protocol of DIL dose escalation by Tomotherapy. All patients were submitted to a multiparametric MRI (including DCE and DWI series), in order to visualize DILs. Considering a mean α/β ratio of 3 for prostate cancer the prescribed doses were: 83.2 Gy in 32 fractions of 2.6 per fraction (EQD2=93.2 Gy) on the DILs, 75.2 Gy in 32 fractions of 2.35 Gy per fraction (EQD2=80.5 Gy) on the prostate gland and 67.2 Gy in 32 fraction of 2.1 (EQD2=68.5 Gy) on the seminal vesicles. With a mean follow-up of 16 months (range 2-39), no overall severe acute toxicities >G3 were observed; one patient out of 15 (6.6%) had acute gastrointestinal (GI) toxicity equal to G2, while two cases (13.3%) had G2 acute genitourinary (GU) toxicity. No >G2 late toxicity was observed. At last follow-up, for all patients, the biochemical disease free survival was 100%. The irradiation of the whole prostate and seminal vesicles up to an EQD2 of 80.5 Gy and of DILs up to 93.2 Gy was clinically feasible and safe, without acute severe toxicity. Although with a short follow-up, late toxicities are currently absent and no patient relapsed.

Utility of Megavoltage Fan-Beam CT for Treatment Planning in a Head-And-Neck Cancer Patient with Extensive Dental Fillings Undergoing Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Claus; Liu Tianxiao; Jennelle, Richard L.

The purpose of this study was to demonstrate the potential utility of megavoltage fan-beam computed tomography (MV-FBCT) for treatment planning in a patient undergoing helical tomotherapy for nasopharyngeal carcinoma in the presence of extensive dental artifact. A 28-year-old female with locally advanced nasopharyngeal carcinoma presented for radiation therapy. Due to the extensiveness of the dental artifact present in the oral cavity kV-CT scan acquired at simulation, which made treatment planning impossible on tomotherapy planning system, MV-FBCT imaging was obtained using the HI-ART tomotherapy treatment machine, with the patient in the treatment position, and this information was registered with her originalmore » kV-CT scan for the purposes of structure delineation, dose calculation, and treatment planning. To validate the feasibility of the MV-FBCT-generated treatment plan, an electron density CT phantom (model 465, Gammex Inc., Middleton, WI) was scanned using MV-FBCT to obtain CT number to density table. Additionally, both a 'cheese' phantom (which came with the tomotherapy treatment machine) with 2 inserted ion chambers and a generic phantom called Quasar phantom (Modus Medical Devices Inc., London, ON, Canada) with one inserted chamber were used to confirm dosimetric accuracy. The MV-FBCT could be used to clearly visualize anatomy in the region of the dental artifact and provide sufficient soft-tissue contrast to assist in the delineation of normal tissue structures and fat planes. With the elimination of the dental artifact, the MV-FBCT images allowed more accurate dose calculation by the tomotherapy system. It was confirmed that the phantom material density was determined correctly by the tomotherapy MV-FBCT number to density table. The ion chamber measurements agreed with the calculations from the MV-FBCT generated phantom plan within 2%. MV-FBCT may be useful in radiation treatment planning for nasopharyngeal cancer patients in the setting of extensive dental artifacts.« less

Peripheral dose measurements with diode and thermoluminescence dosimeters for intensity modulated radiotherapy delivered with conventional and un-conventional linear accelerator

PubMed Central

Kinhikar, Rajesh; Gamre, Poonam; Tambe, Chandrashekhar; Kadam, Sudarshan; Biju, George; Suryaprakash; Magai, C. S.; Dhote, Dipak; Shrivastava, Shyam; Deshpande, Deepak

2013-01-01

The objective of this paper was to measure the peripheral dose (PD) with diode and thermoluminescence dosimeter (TLD) for intensity modulated radiotherapy (IMRT) with linear accelerator (conventional LINAC), and tomotherapy (novel LINAC). Ten patients each were selected from Trilogy dual-energy and from Hi-Art II tomotherapy. Two diodes were kept at 20 and 25 cm from treatment field edge. TLDs (LiF:MgTi) were also kept at same distance. TLDs were also kept at 5, 10, and 15 cm from field edge. The TLDs were read with REXON reader. The readings at the respective distance were recorded for both diode and TLD. The PD was estimated by taking the ratio of measured dose at the particular distance to the prescription dose. PD was then compared with diode and TLD for LINAC and tomotherapy. Mean PD for LINAC with TLD and diode was 2.52 cGy (SD 0.69), 2.07 cGy (SD 0.88) at 20 cm, respectively, while at 25 cm, it was 1.94 cGy (SD 0.58) and 1.5 cGy (SD 0.75), respectively. Mean PD for tomotherapy with TLD and diode was 1.681 cGy SD 0.53) and 1.58 (SD 0.44) at 20 cm, respectively. The PD was 1.24 cGy (SD 0.42) and 1.088 cGy (SD 0.35) at 25 cm, respectively, for tomotherapy. Overall, PD from tomotherapy was found lower than LINAC by the factor of 1.2-1.5. PD measurement is essential to find out the potential of secondary cancer. PD for both (conventional LINAC) and novel LINACs (tomotherapy) were measured and compared with each other. The comparison of the values for PD presented in this work and those published in the literature is difficult because of the different experimental conditions. The diode and TLD readings were reproducible and both the detector readings were comparable. PMID:23531765

Validation of GPU based TomoTherapy dose calculation engine.

PubMed

Chen, Quan; Lu, Weiguo; Chen, Yu; Chen, Mingli; Henderson, Douglas; Sterpin, Edmond

2012-04-01

The graphic processing unit (GPU) based TomoTherapy convolution/superposition(C/S) dose engine (GPU dose engine) achieves a dramatic performance improvement over the traditional CPU-cluster based TomoTherapy dose engine (CPU dose engine). Besides the architecture difference between the GPU and CPU, there are several algorithm changes from the CPU dose engine to the GPU dose engine. These changes made the GPU dose slightly different from the CPU-cluster dose. In order for the commercial release of the GPU dose engine, its accuracy has to be validated. Thirty eight TomoTherapy phantom plans and 19 patient plans were calculated with both dose engines to evaluate the equivalency between the two dose engines. Gamma indices (Γ) were used for the equivalency evaluation. The GPU dose was further verified with the absolute point dose measurement with ion chamber and film measurements for phantom plans. Monte Carlo calculation was used as a reference for both dose engines in the accuracy evaluation in heterogeneous phantom and actual patients. The GPU dose engine showed excellent agreement with the current CPU dose engine. The majority of cases had over 99.99% of voxels with Γ(1%, 1 mm) < 1. The worst case observed in the phantom had 0.22% voxels violating the criterion. In patient cases, the worst percentage of voxels violating the criterion was 0.57%. For absolute point dose verification, all cases agreed with measurement to within ±3% with average error magnitude within 1%. All cases passed the acceptance criterion that more than 95% of the pixels have Γ(3%, 3 mm) < 1 in film measurement, and the average passing pixel percentage is 98.5%-99%. The GPU dose engine also showed similar degree of accuracy in heterogeneous media as the current TomoTherapy dose engine. It is verified and validated that the ultrafast TomoTherapy GPU dose engine can safely replace the existing TomoTherapy cluster based dose engine without degradation in dose accuracy.

Evaluation of 3D Gamma index calculation implemented in two commercial dosimetry systems

NASA Astrophysics Data System (ADS)

Xing, Aitang; Arumugam, Sankar; Deshpande, Shrikant; George, Armia; Vial, Philip; Holloway, Lois; Goozee, Gary

2015-01-01

3D Gamma index is one of the metrics which have been widely used for clinical routine patient specific quality assurance for IMRT, Tomotherapy and VMAT. The algorithms for calculating the 3D Gamma index using global and local methods implemented in two software tools: PTW- VeriSoft® as a part of OCTIVIUS 4D dosimeter systems and 3DVHTM from Sun Nuclear were assessed. The Gamma index calculated by the two systems was compared with manual calculated for one data set. The Gamma pass rate calculated by the two systems was compared using 3%/3mm, 2%/2mm, 3%/2mm and 2%/3mm for two additional data sets. The Gamma indexes calculated by the two systems were accurate, but Gamma pass rates calculated by the two software tools for same data set with the same dose threshold were different due to the different interpolation of raw dose data by the two systems and different implementation of Gamma index calculation and other modules in the two software tools. The mean difference was -1.3%±3.38 (1SD) with a maximum difference of 11.7%.

Characterization of metal oxide field-effect transistors for first helical tomotherapy Hi-Art II unit in India.

PubMed

Kinhikar, Rajesh A; Pai, Rajeshree; Master, Zubin; Deshpande, Deepak D

2009-01-01

To characterize metal oxide semiconductor field-effect transistors (MOSFETs) for a 6-MV photon beam with a first helical tomotherapy Hi-Art II unit in India. Standard sensitivity MOSFETs were first calibrated and then characterized for reproducibility, field size dependence, angular dependence, fade effects, and temperature dependence. The detector sensitivity was estimated for static as well as rotational modes for three jaw settings (1.0 cm x 40 cm, 2.5 cm x 40 cm, and 5 cm x 40 cm) at 1.5-cm depth with a source-to-axis distance (SAD) of 85 cm in virtual water slabs. The A1SL ion chamber and thermoluminescence dosimeters (TLDs) were used to compare the results. No significant difference was found in the detector sensitivity for static and rotational procedures. The average detector sensitivity for static procedures was 1.10 mV/cGy (SD 0.02) while it was 1.12 mV/cGy (SD 0.02) for rotational procedures. The average detector sensitivity found was the same within the experimental uncertainty for static and rotational dose deliveries. The MOSFET reading was consistent and its reproducibility was excellent (+0.5%) while there was no significant dependence of field size. The angular dependence of less than 1.0% was observed. There was negligible fading effect of the MOSFET. The MOSFET response was found independent of temperature in the range 18 degrees-30 degrees. The ion chamber readings were assumed to be a reference for the estimation of the MOSFET calibration factor. The ion chamber and the TLD were in good agreement (+2%) with each other. This study deals only with the measurements and calibration performed on the surface of the phantom. MOSFET was calibrated and validated for phantom surface measurements for a 6-MV photon beam generated by a tomotherapy machine. The sensitivity of the detector was the same for both modes of treatment delivery with tomotherapy. The performance of the MOSFET was validated for and satisfactory for the helical tomotherapy Hi-Art II unit. However, MOSFET may be used for in vivo surface dosimetry only after it is calibrated under the conditions replicating as much as possible the manner in which the dosimeter will be used clinically.

Clinical benefits of new immobilization system for hypofractionated radiotherapy of intrahepatic hepatocellular carcinoma by helical tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Yong; Zhou, Yong-Kang; Chen, Yi-Xing

Objective: A comprehensive clinical evaluation was conducted, assessing the Body Pro-Lok immobilization and positioning system to facilitate hypofractionated radiotherapy of intrahepatic hepatocellular carcinoma (HCC), using helical tomotherapy to improve treatment precision. Methods: Clinical applications of the Body Pro-Lok system were investigated (as above) in terms of interfractional and intrafractional setup errors and compressive abdominal breath control. To assess interfractional setup errors, a total of 42 patients who were given 5 to 20 fractions of helical tomotherapy for intrahepatic HCC were analyzed. Overall, 15 patients were immobilized using simple vacuum cushion (group A), and the Body Pro-Lok system was used inmore » 27 patients (group B), performing megavoltage computed tomography (MVCT) scans 196 times and 435 times, respectively. Pretreatment MVCT scans were registered to the planning kilovoltage computed tomography (KVCT) for error determination, and group comparisons were made. To establish intrafractional setup errors, 17 patients with intrahepatic HCC were selected at random for immobilization by Body Pro-Lok system, undergoing MVCT scans after helical tomotherapy every week. A total of 46 MVCT re-scans were analyzed for this purpose. In researching breath control, 12 patients, randomly selected, were immobilized by Body Pro-Lok system and subjected to 2-phase 4-dimensional CT (4DCT) scans, with compressive abdominal control or in freely breathing states, respectively. Respiratory-induced liver motion was then compared. Results: Mean interfractional setup errors were as follows: (1) group A: X, 2.97 ± 2.47 mm; Y, 4.85 ± 4.04 mm; and Z, 3.77 ± 3.21 mm; pitch, 0.66 ± 0.62°; roll, 1.09 ± 1.06°; and yaw, 0.85 ± 0.82°; and (2) group B: X, 2.23 ± 1.79 mm; Y, 4.10 ± 3.36 mm; and Z, 1.67 ± 1.91 mm; pitch, 0.45 ± 0.38°; roll, 0.77 ± 0.63°; and yaw, 0.52 ± 0.49°. Between-group differences were statistically significant in 6 directions (p < 0.05). Mean intrafractional setup errors with use of the Body Pro-Lok system were as follows: X, 0.41 ± 0.46 mm; Y, 0.86 ± 0.80 mm; Z, 0.33 ± 0.44 mm; and roll, 0.12 ± 0.19°. Mean liver-induced respiratory motion determinations were as follows: (1) abdominal compression: X, 2.33 ± 1.22 mm; Y, 5.11 ± 2.05 mm; Z, 2.13 ± 1.05 mm; and 3D vector, 6.22 ± 1.94 mm; and (2) free breathing: X, 3.48 ± 1.14 mm; Y, 9.83 ± 3.00 mm; Z, 3.38 ± 1.59 mm; and 3D vector, 11.07 ± 3.16 mm. Between-group differences were statistically different in 4 directions (p < 0.05). Conclusions: The Body Pro-Lok system is capable of improving interfractional and intrafractional setup accuracy and minimizing tumor movement owing to respirations in patients with intrahepatic HCC during hypofractionated helical tomotherapy.« less

High-dose MVCT image guidance for stereotactic body radiation therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Westerly, David C.; Schefter, Tracey E.; Kavanagh, Brian D.

Purpose: Stereotactic body radiation therapy (SBRT) is a potent treatment for early stage primary and limited metastatic disease. Accurate tumor localization is essential to administer SBRT safely and effectively. Tomotherapy combines helical IMRT with onboard megavoltage CT (MVCT) imaging and is well suited for SBRT; however, MVCT results in reduced soft tissue contrast and increased image noise compared with kilovoltage CT. The goal of this work was to investigate the use of increased imaging doses on a clinical tomotherapy machine to improve image quality for SBRT image guidance. Methods: Two nonstandard, high-dose imaging modes were created on a tomotherapy machinemore » by increasing the linear accelerator (LINAC) pulse rate from the nominal setting of 80 Hz, to 160 Hz and 300 Hz, respectively. Weighted CT dose indexes (wCTDIs) were measured for the standard, medium, and high-dose modes in a 30 cm solid water phantom using a calibrated A1SL ion chamber. Image quality was assessed from scans of a customized image quality phantom. Metrics evaluated include: contrast-to-noise ratios (CNRs), high-contrast spatial resolution, image uniformity, and percent image noise. In addition, two patients receiving SBRT were localized using high-dose MVCT scans. Raw detector data collected after each scan were used to reconstruct standard-dose images for comparison. Results: MVCT scans acquired using a pitch of 1.0 resulted in wCTDI values of 2.2, 4.7, and 8.5 cGy for the standard, medium, and high-dose modes respectively. CNR values for both low and high-contrast materials were found to increase with the square root of dose. Axial high-contrast spatial resolution was comparable for all imaging modes at 0.5 lp/mm. Image uniformity was improved and percent noise decreased as the imaging dose increased. Similar improvements in image quality were observed in patient images, with decreases in image noise being the most notable. Conclusions: High-dose imaging modes are made possible on a clinical tomotherapy machine by increasing the LINAC pulse rate. Increasing the imaging dose results in increased CNRs; making it easier to distinguish the boundaries of low contrast objects. The imaging dose levels observed in this work are considered acceptable at our institution for SBRT treatments delivered in 3-5 fractions.« less

High-dose MVCT image guidance for stereotactic body radiation therapy.

PubMed

Westerly, David C; Schefter, Tracey E; Kavanagh, Brian D; Chao, Edward; Lucas, Dan; Flynn, Ryan T; Miften, Moyed

2012-08-01

Stereotactic body radiation therapy (SBRT) is a potent treatment for early stage primary and limited metastatic disease. Accurate tumor localization is essential to administer SBRT safely and effectively. Tomotherapy combines helical IMRT with onboard megavoltage CT (MVCT) imaging and is well suited for SBRT; however, MVCT results in reduced soft tissue contrast and increased image noise compared with kilovoltage CT. The goal of this work was to investigate the use of increased imaging doses on a clinical tomotherapy machine to improve image quality for SBRT image guidance. Two nonstandard, high-dose imaging modes were created on a tomotherapy machine by increasing the linear accelerator (LINAC) pulse rate from the nominal setting of 80 Hz, to 160 Hz and 300 Hz, respectively. Weighted CT dose indexes (wCTDIs) were measured for the standard, medium, and high-dose modes in a 30 cm solid water phantom using a calibrated A1SL ion chamber. Image quality was assessed from scans of a customized image quality phantom. Metrics evaluated include: contrast-to-noise ratios (CNRs), high-contrast spatial resolution, image uniformity, and percent image noise. In addition, two patients receiving SBRT were localized using high-dose MVCT scans. Raw detector data collected after each scan were used to reconstruct standard-dose images for comparison. MVCT scans acquired using a pitch of 1.0 resulted in wCTDI values of 2.2, 4.7, and 8.5 cGy for the standard, medium, and high-dose modes respectively. CNR values for both low and high-contrast materials were found to increase with the square root of dose. Axial high-contrast spatial resolution was comparable for all imaging modes at 0.5 lp∕mm. Image uniformity was improved and percent noise decreased as the imaging dose increased. Similar improvements in image quality were observed in patient images, with decreases in image noise being the most notable. High-dose imaging modes are made possible on a clinical tomotherapy machine by increasing the LINAC pulse rate. Increasing the imaging dose results in increased CNRs; making it easier to distinguish the boundaries of low contrast objects. The imaging dose levels observed in this work are considered acceptable at our institution for SBRT treatments delivered in 3-5 fractions.

Optimization of brain metastases radiotherapy with TomoHDA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yartsev, Slav, E-mail: slav.yartsev@lhsc.on.ca; Bauman, Glenn

An upgrade of the helical tomotherapy technology by introducing variable fan-field width (dynamic jaws) reduced the penumbra in superior-inferior direction for the target. Possible implementation of this upgrade even for the cases of the targets with different dose prescriptions is proposed. An example of brain metastasis in proximity to the optical apparatus in need of the whole brain irradiation of 30 Gy and higher dose to the lesion is considered.

Effect of CT contrast on volumetric arc therapy planning (RapidArc and helical tomotherapy) for head and neck cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Alan J.; Vora, Nayana; Suh, Steve

2015-04-01

The objectives of the study were to evaluate the effect of intravenous contrast in the dosimetry of helical tomotherapy and RapidArc treatment for head and neck cancer and determine if it is acceptable during the computed tomography (CT) simulation to acquire only CT with contrast for treatment planning of head and neck cancer. Overall, 5 patients with head and neck cancer (4 men and 1 woman) treated on helical tomotherapy were analyzed retrospectively. For each patient, 2 consecutive CT scans were performed. The first CT set was scanned before the contrast injection and secondary study set was scanned 45 secondsmore » after contrast. The 2 CTs were autoregistered using the same Digital Imaging and Communications in Medicine coordinates. Tomotherapy and RapidArc plans were generated on 1 CT data set and subsequently copied to the second CT set. Dose calculation was performed, and dose difference was analyzed to evaluate the influence of intravenous contrast media. The dose matrix used for comparison included mean, minimum and maximum doses of planning target volume (PTV), PTV dose coverage, and V{sub 45} {sub Gy}, V{sub 30} {sub Gy}, and V{sub 20} {sub Gy} organ doses. Treatment planning on contrasted images generally showed a lower dose to both organs and target than plans on noncontrasted images. The doses for the points of interest placed in the organs and target rarely changed more than 2% in any patient. In conclusion, treatment planning using a contrasted image had insignificant effect on the dose to the organs and targets. In our opinion, only CT with contrast needs to be acquired during the CT simulation for head and neck cancer. Dose calculations performed on contrasted images can potentially underestimate the delivery dose slightly. However, the errors of planning on a contrasted image should not affect the result in clinically significant way.« less

Helical tomotherapy in patients with breast cancer and complex treatment volumes.

PubMed

Cendales, Ricardo; Schiappacasse, Luis; Schnitman, Franco; García, Graciela; Marsiglia, Hugo

2011-04-01

To describe early clinical results of tomotherapy treatment in patients with breast cancer and complex treatment volumes. Ten patients were treated with tomotherapy between January 2009 and March 2010. Treatment planning objectives were to cover at least 95% of the planning target volume with the 95% isodose; to have a minimum dose of 90% and a maximum dose of 105%. All treatments included daily CT/megavoltage image guidance. Acute toxicity was recorded weekly. Six patients were treated because constraints were not accomplished for heart, lung or contralateral breast in a previous three-dimensional conformal plan; two for preexisting cardiac or pulmonary disease, and two more for bilateral breast irradiation. Treatment volumes included the whole breast in the majority of patients, as well as the supraclavicular and the internal mammary chain nodes when indicated. Most patients were older than 50 years, and had an early breast cancer, with positive oestrogen receptors, negative HER2 expression and a poorly differentiated, infiltrating ductal carcinoma. The majority of patients had received neoadjuvant chemotherapy associated to breast-conserving surgery and adjuvant hormonotherapy. Median homogeneity index was 1.09; median coverage index was 0.81. Median V20Gy and V10Gy for ipsilateral lung was 20% and 37.1% respectively. Median V25 and V35 for heart was 15% and 4% respectively. Median dose for contralateral breast was 7 Gy. Skin acute toxicity was grade 1 in 41.7% and grade 2 in 58.3%. Tomotherapy is a technique capable of delivering a well tolerated treatment with high homogeneity and coverage indexes and high capabilities for sparing the organs at risk in patients with anatomically complex breast cancer, bilateral breast cancer, indication for internal mammary chain node irradiation, cardiac toxicity derived from chemotherapy, or preexisting cardiac or pulmonary disease. Further studies are required to evaluate local control and late toxicity.

Poster — Thur Eve — 57: Evaluation of laryngeal mucosal dose with conventional linac and TomoTherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nusrat, H; Lekx, K; Eapen, L

2014-08-15

The purpose of this study was to examine whether or not underdosing occurs in the mucosal layer during treatment of glottis cancer. A larynx phantom was produced and regions at risk of recurrence due to suspected underdosing were identified and wells drilled into the phantom for flush placement of TLDs. Seven interest points were chosen. CT simulation was completed prior to the wells being drilled, and again afterwards with the TLD locations indicated using BBs. Treatment plans created for this investigation included: 3DCRT using Elekta-XiO (n=9) and VMAT created using Elekta-Monaco (n=9), both delivered on an Elekta linac; standard TomoTherapymore » plan (n=11) and a directionally blocked TomoTherapy plan to approximate a 3D-conformal approach (n=5). Imaging dose during TomoTherapy deliveries was accounted for. The average TLD result at each interest point was compared to the planned value using a paired t-test. There was no significant difference between the planned and measured 3DCRT dose (268.9 vs. 267.0 cGy, respectively; p>0.05). Similarly, the planned and measured TomoTherapy treatment did not show any significant differences (271.7 vs 269.7 cGy; p>0.05). In the blocked TomoTherapy plan, significant overdosing was seen (274.5 vs 294.9 cGy; p<0.05) and underdosing was not seen in the VMAT treatment (303.5 vs 321.8 cGy; p>0.05). Further investigation is ongoing to ensure appropriate normalization of results and to investigate the overdosing noted with the blocked TomoTherapy plan. Results from this study suggest that significant underdosing does not occur in the conventional treatment of early glottic cancer using 6MV photons.« less

Influence of tumor location on the intensity-modulated radiation therapy plan of helical tomotherapy.

PubMed

Xu, Yingjie; Yan, Hui; Hu, Zhihui; Ma, Pan; Men, Kuo; Huang, Peng; Ren, Wenting; Dai, Jianrong; Li, Yexiong

2017-01-01

Given the design of the Helical TomoTherapy device, the patient's central axis is routinely aligned with the machine's rotational axis to prevent the patient's body from colliding with the machine walls. However, for treatment of tumors located away from the patient's central axis, this position may not be optimal as the adequate radiation dose may not reach the affected site. Our study aimed to investigate the influence of tumor location on dose quality and delivery efficiency of tomotherapy plans. A phantom and 15 patients were selected for this study. Two plans, A and B, were implemented for each case. In plan A, the patient's central axis was aligned with the machine's rotational axis, whereas in plan B, the center of the planning target volume (PTV) was aligned with the machine's rotational axis. Both plans were optimized with the same planning parameters, and the dose quality of the plans was evaluated using dosimetrics. The delivery efficiency was determined from delivery time and monitor units (MUs). A paired t-test or nonparametric Wilcoxon signed-rank test was performed for statistical comparison. In the phantom study, the median delivery times were 358 and 336 seconds for plans A and B, respectively, and this difference was significant (p = 0.005). In the patient study, the median delivery times were 348 and 317 seconds for plans A and B, respectively, and this difference was also significant (p = 0.001). The dose qualities of both plans for each patient were nearly identical. No significant differences were found in the conformal index, heterogeneity index, and mean dose delivered to normal tissue between the plans. Both phantom and patient studies showed that for normal-sized patients, the delivery time reduced as the distance between the PTV and the patient's central axis increased when the PTV center was aligned with the machine axis. In conclusion, aligning the PTV center with the machine's rotational axis by shifting the patient during tomotherapy reduces the delivery time without compromising the dose quality of intensity-modulated radiation therapy. Copyright © 2017 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

Skin dose measurements using MOSFET and TLD for head and neck patients treated with tomotherapy.

PubMed

Kinhikar, Rajesh A; Murthy, Vedang; Goel, Vineeta; Tambe, Chandrashekar M; Dhote, Dipak S; Deshpande, Deepak D

2009-09-01

The purpose of this work was to estimate skin dose for the patients treated with tomotherapy using metal oxide semiconductor field-effect transistors (MOSFETs) and thermoluminescent dosimeters (TLDs). In vivo measurements were performed for two head and neck patients treated with tomotherapy and compared to TLD measurements. The measurements were subsequently carried out for five days to estimate the inter-fraction deviations in MOSFET measurements. The variation between skin dose measured with MOSFET and TLD for first patient was 2.2%. Similarly, the variation of 2.3% was observed between skin dose measured with MOSFET and TLD for second patient. The tomotherapy treatment planning system overestimated the skin dose as much as by 10-12% when compared to both MOSFET and TLD. However, the MOSFET measured patient skin doses also had good reproducibility, with inter-fraction deviations ranging from 1% to 1.4%. MOSFETs may be used as a viable dosimeter for measuring skin dose in areas where the treatment planning system may not be accurate.

MOSFET detectors in quality assurance of tomotherapy treatments.

PubMed

Cherpak, Amanda; Studinski, Ryan C N; Cygler, Joanna E

2008-02-01

The purpose of this work was to characterize metal oxide semiconductor field-effect transistors (MOSFETs) in a 6 MV conventional linac and investigate their use for quality assurance of radiotherapy treatments with a tomotherapy Hi-Art unit. High sensitivity and standard sensitivity MOSFETs were first calibrated and then tested for reproducibility, field size dependence, and accuracy of measuring surface dose in a 6 MV beam as well as in a tomotherapy Hi-Art unit. In vivo measurements were performed on both a RANDO phantom and several head and neck cancer patients treated with tomotherapy and compared to TLD measurements and treatment plan doses to evaluate the performance of MOSFETs in a high gradient radiation field. The average calibration factor found was 0.345+/-2.5%cGy/mV for the high sensitivity MOSFETs tested and 0.901+/-2.4%cGy/mV for the standard sensitivity MOSFETs. MOSFET measured surface doses had an average agreement with ion chamber measurements of 1.55% for the high sensitivity MOSFET and 5.23% for the standard sensitivity MOSFET when averaged over all trials and field sizes tested. No significant dependence on field size was found for the standard sensitivity MOSFETs, however a maximum difference of 5.34% was found for the high sensitivity MOSFET calibration factors in the field sizes tested. Measurements made with MOSFETS on head and neck patients treated on a tomotherapy Hi-Art unit had an average agreement of (3.26+/-0.03)% with TLD measurements, however the average of the absolute difference between the MOSFET measurements and the treatment plan skin doses was (12.2+/-7.5)%. The MOSFET measured patient skin doses also had good reproducibility, with inter-fraction deviations ranging from 1.4% to 6.6%. Similar results were found from trials using a RANDO phantom. The MOSFETs performed well when used in the tomotherapy Hi-Art unit and did not increase the overall treatment set-up time when used for patient measurements. It was found that MOSFETs are suitable detectors for surface dose measurements in both conventional beam and tomotherapy treatments and they can provide valuable skin dose information in areas where the treatment planning system may not be accurate.

Improving the accuracy of ionization chamber dosimetry in small megavoltage x-ray fields

NASA Astrophysics Data System (ADS)

McNiven, Andrea L.

The dosimetry of small x-ray fields is difficult, but important, in many radiation therapy delivery methods. The accuracy of ion chambers for small field applications, however, is limited due to the relatively large size of the chamber with respect to the field size, leading to partial volume effects, lateral electronic disequilibrium and calibration difficulties. The goal of this dissertation was to investigate the use of ionization chambers for the purpose of dosimetry in small megavoltage photon beams with the aim of improving clinical dose measurements in stereotactic radiotherapy and helical tomotherapy. A new method for the direct determination of the sensitive volume of small-volume ion chambers using micro computed tomography (muCT) was investigated using four nominally identical small-volume (0.56 cm3) cylindrical ion chambers. Agreement between their measured relative volume and ionization measurements (within 2%) demonstrated the feasibility of volume determination through muCT. Cavity-gas calibration coefficients were also determined, demonstrating the promise for accurate ion chamber calibration based partially on muCT. The accuracy of relative dose factor measurements in 6MV stereotactic x-ray fields (5 to 40mm diameter) was investigated using a set of prototype plane-parallel ionization chambers (diameters of 2, 4, 10 and 20mm). Chamber and field size specific correction factors ( CSFQ ), that account for perturbation of the secondary electron fluence, were calculated using Monte Carlo simulation methods (BEAM/EGSnrc simulations). These correction factors (e.g. CSFQ = 1.76 (2mm chamber, 5mm field) allow for accurate relative dose factor (RDF) measurement when applied to ionization readings, under conditions of electronic disequilibrium. With respect to the dosimetry of helical tomotherapy, a novel application of the ion chambers was developed to characterize the fan beam size and effective dose rate. Characterization was based on an adaptation of the computed tomography dose index (CTDI), a concept normally used in diagnostic radiology. This involved experimental determination of the fan beam thickness using the ion chambers to acquire fan beam profiles and extrapolation to a 'zero-size' detector. In conclusion, improvements have been made in the accuracy of small field dosimetry measurements in stereotactic radiotherapy and helical tomotherapy. This was completed through introduction of an original technique involving micro-CT imaging for sensitive volume determination and potentially ion chamber calibration coefficients, the use of appropriate Monte Carlo derived correction factors for RDF measurement, and the exploitation of the partial volume effect for helical tomotherapy fan beam dosimetry. With improved dosimetry for a wide range of challenging small x-ray field situations, it is expected that the patient's radiation safety will be maintained, and that clinical trials will adopt calibration protocols specialized for modern radiotherapy with small fields or beamlets. Keywords. radiation therapy, ionization chambers, small field dosimetry, stereotactic radiotherapy, helical tomotherapy, micro-CT.

Initial experience in treating lung cancer with helical tomotherapy

PubMed Central

Yartsev, S; Dar, AR; Woodford, C; Wong, E; Bauman, G; Van Dyk, J

2007-01-01

Helical tomotherapy is a new form of image-guided radiation therapy that combines features of a linear accelerator and a helical computed tomography (CT) scanner. Megavoltage CT (MVCT) data allow the verification and correction of patient setup on the couch by comparison and image registration with the kilovoltage CT multi-slice images used for treatment planning. An 84-year-old male patient with Stage III bulky non-small cell lung cancer was treated on a Hi-ART II tomotherapy unit. Daily MVCT imaging was useful for setup corrections and signaled the need to adapt the delivery plan when the patient’s anatomy changed significantly. PMID:21614260

Tomotherapy as a tool in image-guided radiation therapy (IGRT): current clinical experience and outcomes

PubMed Central

Yartsev, S; Kron, T; Van Dyk, J

2007-01-01

Modern radiotherapy is characterised by a better target definition through medical imaging accompanied by significantly improved radiation delivery methods, most notably Intensity-Modulate Radiation Therapy (IMRT). However, the treatment can only be as accurate as the positioning of patients for their daily radiotherapy fraction. It is in this context that a number of imaging modalities - ranging from ultrasound to on-board kilovoltage imaging and computed tomography (CT) - have found their way into the treatment room where they verify accurate patient positioning prior to or even during delivery of radiation. Helical tomotherapy (HT) combines IMRT delivery with in-built image guidance using megavoltage CT scanning. This paper discusses the initial experience of different centres with IGRT using HT illustrated by a number of clinical examples from the installation in London in Ontario, Canada, one of the world’s first HT sites. We found that HT allows the delivery of highly conformal radiation dose distributions combined with adequate daily image acquisition. An important feature of this unit is its seamless integration, which also includes a customised inverse treatment planning system and a quality assurance module for individual patients. PMID:21614258

An assessment of the use of skin flashes in helical tomotherapy using phantom and in-vivo dosimetry.

PubMed

Tournel, Koen; Verellen, Dirk; Duchateau, Michael; Fierens, Yves; Linthout, Nadine; Reynders, Truus; Voordeckers, Mia; Storme, Guy

2007-07-01

In helical tomotherapy the nature of the optimizing and planning systems allows the delivery of dose on the skin using a build-up compensating technique (skin flash). However, positioning errors or changes in the patient's contour can influence the correct dosage in these regions. This work studies the behavior of skin-flash regions using phantom and in-vivo dosimetry. The dosimetric accuracy of the tomotherapy planning system in skin-flash regions is checked using film and TLD on phantom. Positioning errors are induced and the effect on the skin dose is investigated. Further a volume decrease is simulated using bolus material and the results are compared. Results show that the tomotherapy planning system calculates dose on skin regions within 2 SD using TLD measurements. Film measurements show drops of dose of 2.8% and 26% for, respectively, a 5mm and 10mm mispositioning of the phantom towards air and a dose increase of 9% for a 5mm shift towards tissue. These measurements are confirmed by TLD measurements. A simulated volume reduction shows a similar behavior with a 2.6% and 19.4% drop in dose, measured with TLDs. The tomotherapy system allows adequate planning and delivery of dose using skin flashes. However, exact positioning is crucial to deliver the dose at the exact location.

Clinical applications of advanced rotational radiation therapy

NASA Astrophysics Data System (ADS)

Nalichowski, Adrian

Purpose: With a fast adoption of emerging technologies, it is critical to fully test and understand its limits and capabilities. In this work we investigate new graphic processing unit (GPU) based treatment planning algorithm and its applications in helical tomotherapy dose delivery. We explore the limits of the system by applying it to challenging clinical cases of total marrow irradiation (TMI) and stereotactic radiosurgery (SRS). We also analyze the feasibility of alternative fractionation schemes for total body irradiation (TBI) and TMI based on reported historical data on lung dose and interstitial pneumonitis (IP) incidence rates. Methods and Materials: An anthropomorphic phantom was used to create TMI plans using the new GPU based treatment planning system and the existing CPU cluster based system. Optimization parameters were selected based on clinically used values for field width, modulation factor and pitch. Treatment plans were also created on Eclipse treatment planning system (Varian Medical Systems Inc, Palo Alto, CA) using volumetric modulated arc therapy (VMAT) for dose delivery on IX treatment unit. A retrospective review was performed of 42 publications that reported IP rates along with lung dose, fractionation regimen, dose rate and chemotherapy. The analysis consisted of nearly thirty two hundred patients and 34 unique radiation regimens. Multivariate logistic regression was performed to determine parameters associated with IP and establish does response function. Results: The results showed very good dosimetric agreement between the GPU and CPU calculated plans. The results from SBRT study show that GPU planning system can maintain 90% target coverage while meeting all the constraints of RTOG 0631 protocol. Beam on time for Tomotherapy and flattening filter free RapidArc was much faster than for Vero or Cyberknife. Retrospective data analysis showed that lung dose and Cyclophosphomide (Cy) are both predictors of IP in TBI/TMI treatments. The dose rate was not found to be an independent risk factor for IP. The model failed to establish accurate dose response function, but the discrete data indicated a radiation dose threshold of 7.6Gy (EQD2_repair) and 120 mg/kg of Cy below which no IP cases were reported. Conclusion: The TomoTherapy GPU based dose engine is capable of calculating TMI treatment plans with plan quality nearly identical to plans calculated using the traditional CPU/cluster based system, while significantly reducing the time required for optimization and dose calculation. The new system was able to achieve more uniform dose distribution throughout the target volume and steeper dose fall off, resulting in superior OAR sparing when compared to Eclipse treatment planning system for VMAT delivery. The machine optimization parameters tested for TMI cases provide a comprehensive overview of the capabilities of the treatment planning station and associated helical delivery system. The new system also proved to be dosimetrically compatible with other leading modalities for treatments of small and complicated target volumes and was even superior when treatment delivery times were compared. These finding demonstrate that the advanced treatment planning and delivery system from TomoTherapy is well suitable for treatments of complicated cases such as TMI and SRS and it's often dosimetrically and/or logistically superior to other modalities. The new planning system can easily meet the constraint of threshold lung dose established in this study. The results presented here on the capabilities of Tomotherapy and on the identified lung dose threshold provide an opportunity to explore alternative fractionation schemes without sacrificing target coverage or lung toxicity. (Abstract shortened by ProQuest.).

Optimization of brain metastases radiotherapy with TomoHDA.

PubMed

Yartsev, Slav; Bauman, Glenn

2017-01-01

An upgrade of the helical tomotherapy technology by introducing variable fan-field width (dynamic jaws) reduced the penumbra in superior-inferior direction for the target. Possible implementation of this upgrade even for the cases of the targets with different dose prescriptions is proposed. An example of brain metastasis in proximity to the optical apparatus in need of the whole brain irradiation of 30 Gy and higher dose to the lesion is considered. Copyright © 2017 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

Dose to organs at risk in the upper abdomen in patients treated with extended fields by helical tomotherapy: a dosimetric and clinical preliminary study

PubMed Central

2013-01-01

Background The aim of this work was to determine the technical feasibility and safety of extended-field radiotherapy (EF), performed by Helical TomoTherapy, in patients with positive pelvic and/or para-aortic nodes. Dosimetric data were collected and acute and sub-acute toxicities of the upper abdominal organs at risk (OAR) were evaluated. Methods Twenty-nine patients suitable for EF irradiation for local disease and/or nodal disease in the pelvic or para-aortic area were treated. The prescription dose was 50.4/54 Gy (1.7-1.8 Gy/fraction) for prophylactic lymph nodes (N-) and 60–70.5 Gy (2–2.35 Gy/fraction) for clinically evident gross disease (N+). Modulation factor (MF), pitch and field width (FW) were chosen to optimize dose distribution and treatment duration. Dose values of PTVs and OAR were analysed. The length of the treatment field, the N + and N- volumes, and treatment duration were reported. To evaluate the safety of treatment, haematological, hepatic, renal and pancreatic functions were assessed before, during and after treatment. The median follow-up time was 17.6 months (range: 6–22 months). Results The treatment was well tolerated and all patients but one completed treatment without interruption. Four of the 29 patients experienced G3 haematological acute toxicity (13.8%), but no patient experienced sub-acute grade G3 toxicity. Ten patients experienced G1 and three G2 acute gastrointestinal toxicity (nausea). No sub-acute gastrointestinal or renal toxicity was observed. Only one (3.7%) patient had a persistent slight increase of pancreatic enzymes and two (7.4%) patients a slight increase of hepatic enzymes six months after radiotherapy (G1 toxicity). Conclusions With our treatment design and dose regimen, we found that EF treatment by TomoTherapy could be safely and effectively delivered with minimal acute and sub-acute toxicities in the upper abdomen area. PMID:24160769

Dose to organs at risk in the upper abdomen in patients treated with extended fields by helical tomotherapy: a dosimetric and clinical preliminary study.

PubMed

Bresciani, Sara; Garibaldi, Elisabetta; Cattari, Gabriella; Maggio, Angelo; Di Dia, Amalia; Delmastro, Elena; Gabriele, Domenico; Stasi, Michele; Gabriele, Pietro

2013-10-25

The aim of this work was to determine the technical feasibility and safety of extended-field radiotherapy (EF), performed by Helical TomoTherapy, in patients with positive pelvic and/or para-aortic nodes. Dosimetric data were collected and acute and sub-acute toxicities of the upper abdominal organs at risk (OAR) were evaluated. Twenty-nine patients suitable for EF irradiation for local disease and/or nodal disease in the pelvic or para-aortic area were treated. The prescription dose was 50.4/54 Gy (1.7-1.8 Gy/fraction) for prophylactic lymph nodes (N-) and 60-70.5 Gy (2-2.35 Gy/fraction) for clinically evident gross disease (N+). Modulation factor (MF), pitch and field width (FW) were chosen to optimize dose distribution and treatment duration. Dose values of PTVs and OAR were analysed. The length of the treatment field, the N + and N- volumes, and treatment duration were reported. To evaluate the safety of treatment, haematological, hepatic, renal and pancreatic functions were assessed before, during and after treatment. The median follow-up time was 17.6 months (range: 6-22 months). The treatment was well tolerated and all patients but one completed treatment without interruption. Four of the 29 patients experienced G3 haematological acute toxicity (13.8%), but no patient experienced sub-acute grade G3 toxicity. Ten patients experienced G1 and three G2 acute gastrointestinal toxicity (nausea). No sub-acute gastrointestinal or renal toxicity was observed. Only one (3.7%) patient had a persistent slight increase of pancreatic enzymes and two (7.4%) patients a slight increase of hepatic enzymes six months after radiotherapy (G1 toxicity). With our treatment design and dose regimen, we found that EF treatment by TomoTherapy could be safely and effectively delivered with minimal acute and sub-acute toxicities in the upper abdomen area.

NOTE: Optimization of megavoltage CT scan registration settings for thoracic cases on helical tomotherapy

NASA Astrophysics Data System (ADS)

Woodford, Curtis; Yartsev, Slav; Van Dyk, Jake

2007-08-01

This study aims to investigate the settings that provide optimum registration accuracy when registering megavoltage CT (MVCT) studies acquired on tomotherapy with planning kilovoltage CT (kVCT) studies of patients with lung cancer. For each experiment, the systematic difference between the actual and planned positions of the thorax phantom was determined by setting the phantom up at the planning isocenter, generating and registering an MVCT study. The phantom was translated by 5 or 10 mm, MVCT scanned, and registration was performed again. A root-mean-square equation that calculated the residual error of the registration based on the known shift and systematic difference was used to assess the accuracy of the registration process. The phantom study results for 18 combinations of different MVCT/kVCT registration options are presented and compared to clinical registration data from 17 lung cancer patients. MVCT studies acquired with coarse (6 mm), normal (4 mm) and fine (2 mm) slice spacings could all be registered with similar residual errors. No specific combination of resolution and fusion selection technique resulted in a lower residual error. A scan length of 6 cm with any slice spacing registered with the full image fusion selection technique and fine resolution will result in a low residual error most of the time. On average, large corrections made manually by clinicians to the automatic registration values are infrequent. Small manual corrections within the residual error averages of the registration process occur, but their impact on the average patient position is small. Registrations using the full image fusion selection technique and fine resolution of 6 cm MVCT scans with coarse slices have a low residual error, and this strategy can be clinically used for lung cancer patients treated on tomotherapy. Automatic registration values are accurate on average, and a quick verification on a sagittal MVCT slice should be enough to detect registration outliers.

Monte Carlo simulations of patient dose perturbations in rotational-type radiotherapy due to a transverse magnetic field: A tomotherapy investigation

PubMed Central

Yang, Y. M.; Geurts, M.; Smilowitz, J. B.; Sterpin, E.; Bednarz, B. P.

2015-01-01

Purpose: Several groups are exploring the integration of magnetic resonance (MR) image guidance with radiotherapy to reduce tumor position uncertainty during photon radiotherapy. The therapeutic gain from reducing tumor position uncertainty using intrafraction MR imaging during radiotherapy could be partially offset if the negative effects of magnetic field-induced dose perturbations are not appreciated or accounted for. The authors hypothesize that a more rotationally symmetric modality such as helical tomotherapy will permit a systematic mediation of these dose perturbations. This investigation offers a unique look at the dose perturbations due to homogeneous transverse magnetic field during the delivery of Tomotherapy® Treatment System plans under varying degrees of rotational beamlet symmetry. Methods: The authors accurately reproduced treatment plan beamlet and patient configurations using the Monte Carlo code geant4. This code has a thoroughly benchmarked electromagnetic particle transport physics package well-suited for the radiotherapy energy regime. The three approved clinical treatment plans for this study were for a prostate, head and neck, and lung treatment. The dose heterogeneity index metric was used to quantify the effect of the dose perturbations to the target volumes. Results: The authors demonstrate the ability to reproduce the clinical dose–volume histograms (DVH) to within 4% dose agreement at each DVH point for the target volumes and most planning structures, and therefore, are able to confidently examine the effects of transverse magnetic fields on the plans. The authors investigated field strengths of 0.35, 0.7, 1, 1.5, and 3 T. Changes to the dose heterogeneity index of 0.1% were seen in the prostate and head and neck case, reflecting negligible dose perturbations to the target volumes, a change from 5.5% to 20.1% was observed with the lung case. Conclusions: This study demonstrated that the effect of external magnetic fields can be mitigated by exploiting a more rotationally symmetric treatment modality. PMID:25652485

SU-E-J-29: Automatic Image Registration Performance of Three IGRT Systems for Prostate Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barber, J; University of Sydney, Sydney, NSW; Sykes, J

Purpose: To compare the performance of an automatic image registration algorithm on image sets collected on three commercial image guidance systems, and explore its relationship with imaging parameters such as dose and sharpness. Methods: Images of a CIRS Virtually Human Male Pelvis phantom (VHMP) were collected on the CBCT systems of Varian TrueBeam/OBI and Elekta Synergy/XVI linear accelerators, across a range of mAs settings; and MVCT on a Tomotherapy Hi-ART accelerator with a range of pitch. Using the 6D correlation ratio algorithm of XVI, each image was registered to a mask of the prostate volume with a 5 mm expansion.more » Registrations were repeated 100 times, with random initial offsets introduced to simulate daily matching. Residual registration errors were calculated by correcting for the initial phantom set-up error. Automatic registration was also repeated after reconstructing images with different sharpness filters. Results: All three systems showed good registration performance, with residual translations <0.5mm (1σ) for typical clinical dose and reconstruction settings. Residual rotational error had larger range, with 0.8°, 1.2° and 1.9° for 1σ in XVI, OBI and Tomotherapy respectively. The registration accuracy of XVI images showed a strong dependence on imaging dose, particularly below 4mGy. No evidence of reduced performance was observed at the lowest dose settings for OBI and Tomotherapy, but these were above 4mGy. Registration failures (maximum target registration error > 3.6 mm on the surface of a 30mm sphere) occurred in 5% to 10% of registrations. Changing the sharpness of image reconstruction had no significant effect on registration performance. Conclusions: Using the present automatic image registration algorithm, all IGRT systems tested provided satisfactory registrations for clinical use, within a normal range of acquisition settings.« less

A non-voxel-based broad-beam (NVBB) framework for IMRT treatment planning.

PubMed

Lu, Weiguo

2010-12-07

We present a novel framework that enables very large scale intensity-modulated radiation therapy (IMRT) planning in limited computation resources with improvements in cost, plan quality and planning throughput. Current IMRT optimization uses a voxel-based beamlet superposition (VBS) framework that requires pre-calculation and storage of a large amount of beamlet data, resulting in large temporal and spatial complexity. We developed a non-voxel-based broad-beam (NVBB) framework for IMRT capable of direct treatment parameter optimization (DTPO). In this framework, both objective function and derivative are evaluated based on the continuous viewpoint, abandoning 'voxel' and 'beamlet' representations. Thus pre-calculation and storage of beamlets are no longer needed. The NVBB framework has linear complexities (O(N(3))) in both space and time. The low memory, full computation and data parallelization nature of the framework render its efficient implementation on the graphic processing unit (GPU). We implemented the NVBB framework and incorporated it with the TomoTherapy treatment planning system (TPS). The new TPS runs on a single workstation with one GPU card (NVBB-GPU). Extensive verification/validation tests were performed in house and via third parties. Benchmarks on dose accuracy, plan quality and throughput were compared with the commercial TomoTherapy TPS that is based on the VBS framework and uses a computer cluster with 14 nodes (VBS-cluster). For all tests, the dose accuracy of these two TPSs is comparable (within 1%). Plan qualities were comparable with no clinically significant difference for most cases except that superior target uniformity was seen in the NVBB-GPU for some cases. However, the planning time using the NVBB-GPU was reduced many folds over the VBS-cluster. In conclusion, we developed a novel NVBB framework for IMRT optimization. The continuous viewpoint and DTPO nature of the algorithm eliminate the need for beamlets and lead to better plan quality. The computation parallelization on a GPU instead of a computer cluster significantly reduces hardware and service costs. Compared with using the current VBS framework on a computer cluster, the planning time is significantly reduced using the NVBB framework on a single workstation with a GPU card.

Application of failure mode and effects analysis (FMEA) to pretreatment phases in tomotherapy.

PubMed

Broggi, Sara; Cantone, Marie Claire; Chiara, Anna; Di Muzio, Nadia; Longobardi, Barbara; Mangili, Paola; Veronese, Ivan

2013-09-06

The aim of this paper was the application of the failure mode and effects analysis (FMEA) approach to assess the risks for patients undergoing radiotherapy treatments performed by means of a helical tomotherapy unit. FMEA was applied to the preplanning imaging, volume determination, and treatment planning stages of the tomotherapy process and consisted of three steps: 1) identification of the involved subprocesses; 2) identification and ranking of the potential failure modes, together with their causes and effects, using the risk probability number (RPN) scoring system; and 3) identification of additional safety measures to be proposed for process quality and safety improvement. RPN upper threshold for little concern of risk was set at 125. A total of 74 failure modes were identified: 38 in the stage of preplanning imaging and volume determination, and 36 in the stage of planning. The threshold of 125 for RPN was exceeded in four cases: one case only in the phase of preplanning imaging and volume determination, and three cases in the stage of planning. The most critical failures appeared related to (i) the wrong or missing definition and contouring of the overlapping regions, (ii) the wrong assignment of the overlap priority to each anatomical structure, (iii) the wrong choice of the computed tomography calibration curve for dose calculation, and (iv) the wrong (or not performed) choice of the number of fractions in the planning station. On the basis of these findings, in addition to the safety strategies already adopted in the clinical practice, novel solutions have been proposed for mitigating the risk of these failures and to increase patient safety.

MO-FG-BRA-07: Intrafractional Motion Effect Can Be Minimized in Tomotherapy Stereotactic Body Radiotherapy (SBRT)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Price, A; Chang, S; Matney, J

2016-06-15

Purpose: Tomotherapy has unique challenges in handling intrafractional motion compared to conventional LINAC. In this study, we analyzed the impact of intrafractional motion on cumulative dosimetry using actual patient motion data and investigated real time jaw/MLC compensation approaches to minimize the motion-induced dose discrepancy in Tomotherapy SBRT treatment. Methods: Intrafractional motion data recorded in two CyberKnife lung treatment cases through fiducial tracking and two LINAC prostate cases through Calypso tracking were used in this study. For each treatment site, one representative case has an average motion (6mm) and one has a large motion (10mm for lung and 15mm for prostate).more » The cases were re-planned on Tomotherapy for SBRT. Each case was planned with 3 different jaw settings: 1cm static, 2.5cm dynamic, and 5cm dynamic. 4D dose accumulation software was developed to compute dose with the recorded motions and theoretically compensate motions by modifying original jaw and MLC to track the trajectory of the tumor. Results: PTV coverage in Tomotherapy SBRT for patients with intrafractional motion depends on motion type, amplitude and plan settings. For the prostate patient with large motion, PTV coverage changed from 97.2% (motion-free) to 47.1% (target motion-included), 96.6% to 58.5% and 96.3% to 97.8% for the 1cm static jaw, 2.5cm dynamic jaw and 5cm dynamic jaw setting, respectively. For the lung patient with large motion, PTV coverage discrepancies showed a similar trend of change. When the jaw and MLC compensation program was engaged, the motion compromised PTV coverage was recovered back to >95% for all cases and plans. All organs at risk (OAR) were spared with < 5% increase from original motion-free plans. Conclusion: Tomotherapy SBRT is less motion-impacted when 5cm dynamic jaw is used. Once the motion pattern is known, the jaw and MLC compensation program can largely minimize the compromised target coverage and OAR sparing.« less

SU-F-T-485: Independent Remote Audits for TG51 NonCompliant Photon Beams Performed by the IROC Houston QA Center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alvarez, P; Molineu, A; Lowenstein, J

Purpose: IROC-H conducts external audits for output check verification of photon and electron beams. Many of these beams can meet the geometric requirements of the TG 51 calibration protocol. For those photon beams that are non TG 51 compliant like Elekta GammaKnife, Accuray CyberKnife and TomoTherapy, IROC-H has specific audit tools to monitor the reference calibration. Methods: IROC-H used its TLD and OSLD remote monitoring systems to verify the output of machines with TG 51 non compliant beams. Acrylic OSLD miniphantoms are used for the CyberKnife. Special TLD phantoms are used for TomoTherapy and GammaKnife machines to accommodate the specificmore » geometry of each machine. These remote audit tools are sent to institutions to be irradiated and returned to IROC-H for analysis. Results: The average IROC-H/institution ratios for 480 GammaKnife, 660 CyberKnife and 907 rotational TomoTherapy beams are 1.000±0.021, 1.008±0.019, 0.974±0.023, respectively. In the particular case of TomoTherapy, the overall ratio is 0.977±0.022 for HD units. The standard deviations of all results are consistent with values determined for TG 51 compliant photon beams. These ratios have shown some changes compared to values presented in 2008. The GammaKnife results were corrected by an experimentally determined scatter factor of 1.025 in 2013. The TomoTherapy helical beam results are now from a rotational beam whereas in 2008 the results were from a static beam. The decision to change modality was based on recommendations from the users. Conclusion: External audits of beam outputs is a valuable tool to confirm the calibrations of photon beams regardless of whether the machine is TG 51 or TG 51 non compliant. The difference found for TomoTherapy units is under investigation. This investigation was supported by IROC grant CA180803 awarded by the NCI.« less

Novel Application of Helical Tomotherapy in Whole Skull Palliative Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodrigues, George; Yartsev, Slav; Coad, Terry

2008-01-01

Helical tomotherapy (HT) is a radiation planning/delivery platform that combines inversely planned IMRT with on-board megavoltage imaging. A unique HT radiotherapy whole skull brain sparing technique is described in a patient with metastatic prostate cancer. An inverse HT plan and an accompanying back-up conventional lateral 6-MV parallel opposed pair (POP) plan with corresponding isodose distributions and dose-volume histograms (DVH) were created and assessed prior to initiation of therapy. Plans conforming to the planning treatment volume (PTV) with significant sparing of brain, optic nerve, and eye were created. Dose heterogeneity to the PTV target was slightly higher in the HT planmore » compared to the back-up POP plan. Conformal sparing of brain, optic nerve, and eye was achieved by the HT plan. Similar lens and brain stem/spinal cord doses were seen with both plans. Prospective clinical evaluation with relevant end points (quality of life, symptom relief) are required to confirm the potential benefits of highly conformal therapies applied to palliative situations such as this case.« less

Hippocampal-Sparing Whole-Brain Radiotherapy: A 'How-To' Technique Using Helical Tomotherapy and Linear Accelerator-Based Intensity-Modulated Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gondi, Vinai; Tolakanahalli, Ranjini; Mehta, Minesh P.

2010-11-15

Purpose: Sparing the hippocampus during cranial irradiation poses important technical challenges with respect to contouring and treatment planning. Herein we report our preliminary experience with whole-brain radiotherapy using hippocampal sparing for patients with brain metastases. Methods and Materials: Five anonymous patients previously treated with whole-brain radiotherapy with hippocampal sparing were reviewed. The hippocampus was contoured, and hippocampal avoidance regions were created using a 5-mm volumetric expansion around the hippocampus. Helical tomotherapy and linear accelerator (LINAC)-based intensity-modulated radiotherapy (IMRT) treatment plans were generated for a prescription dose of 30 Gy in 10 fractions. Results: On average, the hippocampal avoidance volume wasmore » 3.3 cm{sup 3}, occupying 2.1% of the whole-brain planned target volume. Helical tomotherapy spared the hippocampus, with a median dose of 5.5 Gy and maximum dose of 12.8 Gy. LINAC-based IMRT spared the hippocampus, with a median dose of 7.8 Gy and maximum dose of 15.3 Gy. On a per-fraction basis, mean dose to the hippocampus (normalized to 2-Gy fractions) was reduced by 87% to 0.49 Gy{sub 2} using helical tomotherapy and by 81% to 0.73 Gy{sub 2} using LINAC-based IMRT. Target coverage and homogeneity was acceptable with both IMRT modalities, with differences largely attributed to more rapid dose fall-off with helical tomotherapy. Conclusion: Modern IMRT techniques allow for sparing of the hippocampus with acceptable target coverage and homogeneity. Based on compelling preclinical evidence, a Phase II cooperative group trial has been developed to test the postulated neurocognitive benefit.« less

Radiation shielding design of a new tomotherapy facility.

PubMed

Zacarias, Albert; Balog, John; Mills, Michael

2006-10-01

It is expected that intensity modulated radiation therapy (IMRT) and image guided radiation therapy (IGRT) will replace a large portion of radiation therapy treatments currently performed with conventional MLC-based 3D conformal techniques. IGRT may become the standard of treatment in the future for prostate and head and neck cancer. Many established facilities may convert existing vaults to perform this treatment method using new or upgraded equipment. In the future, more facilities undoubtedly will be considering de novo designs for their treatment vaults. A reevaluation of the design principles used in conventional vault design is of benefit to those considering this approach with a new tomotherapy facility. This is made more imperative as the design of the TomoTherapy system is unique in several aspects and does not fit well into the formalism of NCRP 49 for a conventional linear accelerator.

Performance evaluation of the RITG148+ set of TomoTherapy quality assurance tools using RTQA2 radiochromic film.

PubMed

Lobb, Eric C

2016-07-08

Version 6.3 of the RITG148+ software package offers eight automated analysis routines for quality assurance of the TomoTherapy platform. A performance evaluation of each routine was performed in order to compare RITG148+ results with traditionally accepted analysis techniques and verify that simulated changes in machine parameters are correctly identified by the software. Reference films were exposed according to AAPM TG-148 methodology for each routine and the RITG148+ results were compared with either alternative software analysis techniques or manual analysis techniques in order to assess baseline agreement. Changes in machine performance were simulated through translational and rotational adjustments to subsequently irradiated films, and these films were analyzed to verify that the applied changes were accurately detected by each of the RITG148+ routines. For the Hounsfield unit routine, an assessment of the "Frame Averaging" functionality and the effects of phantom roll on the routine results are presented. All RITG148+ routines reported acceptable baseline results consistent with alternative analysis techniques, with 9 of the 11 baseline test results showing agreement of 0.1mm/0.1° or better. Simulated changes were correctly identified by the RITG148+ routines within approximately 0.2 mm/0.2° with the exception of the Field Centervs. Jaw Setting routine, which was found to have limited accuracy in cases where field centers were not aligned for all jaw settings due to inaccurate autorotation of the film during analysis. The performance of the RITG148+ software package was found to be acceptable for introduction into our clinical environment as an automated alternative to traditional analysis techniques for routine TomoTherapy quality assurance testing.

Application of failure mode and effects analysis (FMEA) to pretreatment phases in tomotherapy

PubMed Central

Broggi, Sara; Cantone, Marie Claire; Chiara, Anna; Muzio, Nadia Di; Longobardi, Barbara; Mangili, Paola

2013-01-01

The aim of this paper was the application of the failure mode and effects analysis (FMEA) approach to assess the risks for patients undergoing radiotherapy treatments performed by means of a helical tomotherapy unit. FMEA was applied to the preplanning imaging, volume determination, and treatment planning stages of the tomotherapy process and consisted of three steps: 1) identification of the involved subprocesses; 2) identification and ranking of the potential failure modes, together with their causes and effects, using the risk probability number (RPN) scoring system; and 3) identification of additional safety measures to be proposed for process quality and safety improvement. RPN upper threshold for little concern of risk was set at 125. A total of 74 failure modes were identified: 38 in the stage of preplanning imaging and volume determination, and 36 in the stage of planning. The threshold of 125 for RPN was exceeded in four cases: one case only in the phase of preplanning imaging and volume determination, and three cases in the stage of planning. The most critical failures appeared related to (i) the wrong or missing definition and contouring of the overlapping regions, (ii) the wrong assignment of the overlap priority to each anatomical structure, (iii) the wrong choice of the computed tomography calibration curve for dose calculation, and (iv) the wrong (or not performed) choice of the number of fractions in the planning station. On the basis of these findings, in addition to the safety strategies already adopted in the clinical practice, novel solutions have been proposed for mitigating the risk of these failures and to increase patient safety. PACS number: 87.55.Qr PMID:24036868

A motion phantom study on helical tomotherapy: the dosimetric impacts of delivery technique and motion

NASA Astrophysics Data System (ADS)

Kanagaki, Brian; Read, Paul W.; Molloy, Janelle A.; Larner, James M.; Sheng, Ke

2007-01-01

Helical tomotherapy (HT) can potentially be used for lung cancer treatment including stereotactic radiosurgery because of its advanced image guidance and its ability to deliver highly conformal dose distributions. However, previous theoretical and simulation studies reported that the effect of respiratory motion on statically planned tomotherapy treatments may cause substantial differences between the calculated and actual delivered radiation isodose distribution, particularly when the treatment is hypofractionated. In order to determine the dosimetric effects of motion upon actual HT treatment delivery, phantom film dosimetry measurements were performed under static and moving conditions using a clinical HT treatment unit. The motion phantom system was constructed using a programmable motor, a base, a moving platform and a life size lung heterogeneity phantom with wood inserts representing lung tissue with a 3.0 cm diameter spherical tumour density equivalent insert. In order to determine the effects of different motion and tomotherapy delivery parameters, treatment plans were created using jaw sizes of 1.04 cm and 2.47 cm, with incremental gantry rotation periods between the minimum allowed (10 s) and the maximum allowed (60 s). The couch speed varied from 0.009 cm s-1 to 0.049 cm s-1, and delivered to a phantom under static and dynamic conditions with peak-to-peak motion amplitudes of 1.2 cm and 2 cm and periods of 3 and 5 s to simulate human respiratory motion of lung tumours. A cylindrical clinical target volume (CTV) was contoured to tightly enclose the tumour insert. 2.0 Gy was prescribed to 95% of the CTV. Two-dimensional dose was measured by a Kodak EDR2 film. Dynamic phantom doses were then quantitatively compared to static phantom doses in terms of axial dose profiles, cumulative dose volume histograms (DVH), percentage of CTV receiving the prescription dose and the minimum dose received by 95% of the CTV. The larger motion amplitude resulted in more under-dosing at the ends of the CTV in the axis of motion, and this effect was greater for the smaller jaw size plans. Due to the size of the penumbra, the 2.47 cm jaw plans provide adequate coverage for smaller amplitudes of motion, ±0.6 cm in our experiment, without adding any additional margin in the axis of motion to the treatment volume. The periodic heterogeneous patterns described by previous studies were not observed from the single fraction of the phantom measurement. Besides the jaw sizes, CTV dose coverage is not significantly dependent on machine and phantom motion periods. The lack of adverse synchronization patterns from both results validate that HT is a safe technique for treating moving target and hypofractionation.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lian, J; Yuan, L; Wu, Q

Purpose: The quality and efficiency of radiotherapy treatment planning are highly planer dependent. Previously we have developed a statistical model to correlate anatomical features with dosimetry features of head and neck Tomotherapy treatment. The model enables us to predict the best achievable dosimetry for individual patient prior to treatment planning. The purpose of this work is to study if the prediction model can facilitate the treatment planning in both the efficiency and dosimetric quality. Methods: The anatomy-dosimetry correlation model was used to calculate the expected DVH for nine patients formerly treated. In Group A (3 patients), the model prediction agreedmore » with the clinic plan; in Group B (3 patients), the model predicted lower larynx mean dose than the clinic plan; in Group C (3 patients), the model suggested the brainstem could be further spared. Guided by the prior knowledge, we re-planned all 9 cases. The number of interactions during the optimization process and dosimetric endpoints between the original clinical plan and model-guided re-plan were compared. Results: For Group A, the difference of target coverage and organs-at-risk sparing is insignificant (p>0.05) between the replan and the clinical plan. For Group B, the clinical plan larynx median dose is 49.4±4.7 Gy, while the prediction suggesting 40.0±6.2 Gy (p<0.05). The re-plan achieved 41.5±6.6 Gy, with similar dose on other structures as clinical plan. For Group C, the clinical plan brainstem maximum dose is 44.7±5.5 Gy. The model predicted lower value 32.2±3.8 Gy (p<0.05). The re-plans reduced brainstem maximum dose to 31.8±4.1 Gy without affecting the dosimetry of other structures. In the replanning of the 9 cases, the times operator interacted with TPS are reduced on average about 50% compared to the clinical plan. Conclusion: We have demonstrated that the prior expert knowledge embedded model improved the efficiency and quality of Tomotherapy treatment planning.« less

Automated customized retrieval of radiotherapy data for clinical trials, audit and research.

PubMed

Romanchikova, Marina; Harrison, Karl; Burnet, Neil G; Hoole, Andrew Cf; Sutcliffe, Michael Pf; Parker, Michael Andrew; Jena, Rajesh; Thomas, Simon James

2018-02-01

To enable fast and customizable automated collection of radiotherapy (RT) data from tomotherapy storage. Human-readable data maps (TagMaps) were created to generate DICOM-RT (Digital Imaging and Communications in Medicine standard for Radiation Therapy) data from tomotherapy archives, and provided access to "hidden" information comprising delivery sinograms, positional corrections and adaptive-RT doses. 797 data sets totalling 25,000 scans were batch-exported in 31.5 h. All archived information was restored, including the data not available via commercial software. The exported data were DICOM-compliant and compatible with major commercial tools including RayStation, Pinnacle and ProSoma. The export ran without operator interventions. The TagMap method for DICOM-RT data modelling produced software that was many times faster than the vendor's solution, required minimal operator input and delivered high volumes of vendor-identical DICOM data. The approach is applicable to many clinical and research data processing scenarios and can be adapted to recover DICOM-RT data from other proprietary storage types such as Elekta, Pinnacle or ProSoma. Advances in knowledge: A novel method to translate data from proprietary storage to DICOM-RT is presented. It provides access to the data hidden in electronic archives, offers a working solution to the issues of data migration and vendor lock-in and paves the way for large-scale imaging and radiomics studies.

Secondary Cutaneous Involvement in Follicular Diffuse Lymphoma Treated with Helical Tomotherapy

PubMed Central

Dar, A. Rashid; Jordan, Kevin

2017-01-01

Non-Hodgkin’s lymphoma is a complex heterogeneous group of disease entities that involves nodal and extranodal tissues. Cutaneous involvement can occur either as a primary or secondary in course of disease. Radiation therapy with either total body or localized treatments is often used for local control and symptom relief, depending on the target volume. We describe a 60-year-old male with a remote history of stage IA left neck follicular lymphoma treated with radiation 20 years ago and previous relapses aggressively treated by chemotherapy. Treatment to a large volume of back and posterior shoulders on a helical tomotherapy radiotherapy system is reported. The skin lesions responded completely with no toxicity. Palliative radiotherapy to a fairly large and complex volume of skin with modest dose avoiding underlying critical tissues on tomotherapy is feasible, well tolerated with an excellent durable response, without compromising future chemotherapy and stem cell transplant for systemic relapse. PMID:28944110

Dosimetric comparison of different treatment modalities for stereotactic radiotherapy.

PubMed

Hsu, Shih-Ming; Lai, Yuan-Chun; Jeng, Chien-Chung; Tseng, Chia-Ying

2017-09-16

The modalities for performing stereotactic radiotherapy (SRT) on the brain include the cone-based linear accelerator (linac), the flattening filter-free (FFF) volumetric modulated arc therapy (VMAT) linac, and tomotherapy. In this study, the cone-based linac, FFF-VMAT linac, and tomotherapy modalities were evaluated by measuring the differences in doses delivered during brain SRT and experimentally assessing the accuracy of the output radiation doses through clinical measurements. We employed a homemade acrylic dosimetry phantom representing the head, within which a thermoluminescent dosimeter (TLD) and radiochromic EBT3 film were installed. Using the conformity/gradient index (CGI) and Paddick methods, the quality of the doses delivered by the various SRT modalities was evaluated. The quality indicators included the uniformity, conformity, and gradient indices. TLDs and EBT3 films were used to experimentally assess the accuracy of the SRT dose output. The dose homogeneity indices of all the treatment modalities were lower than 1.25. The cone-based linac had the best conformity for all tumors, regardless of the tumor location and size, followed by the FFF-VMAT linac; tomography was the worst-performing treatment modality in this regard. The cone-based linac had the best gradient, regardless of the tumor location and size, whereas the FFF-VMAT linac had a better gradient than tomotherapy for a large tumor diameter (28 mm). The TLD and EBT3 measurements of the dose at the center of tumors indicated that the average difference between the measurements and the calculated dose was generally less than 4%. When the 3% 3-mm gamma passing rate metric was used, the average passing rates of all three treatment modalities exceeded 98%. Regarding the dose, the cone-based linac had the best conformity and steepest dose gradient for tumors of different sizes and distances from the brainstem. The results of this study suggest that SRT should be performed using the cone-based linac on tumors that require treatment plans with a steep dose gradient, even as the tumor is slightly irregular, we should also consider using a high dose gradient of the cone base to treat and protect the normal tissue. If normal tissues require special protection exist at positions that are superior or inferior to the tumor, we can consider using tomotherapy or Cone base with couch at 0° for treatment.

Evaluation of the clinical usefulness of modulated arc treatment

NASA Astrophysics Data System (ADS)

Lee, Young Kyu; Jang, Hong Seok; Kim, Yeon Sil; Choi, Byung Ock; Kang, Young-Nam; Nam, Sang Hee; Park, Hyeong Wook; Kim, Shin Wook; Shin, Hun Joo; Lee, Jae Choon; Kim, Ji Na; Park, Sung Kwang; Kim, Jin Young

2015-07-01

The purpose of this study is to evaluate the clinical usefulness of modulated arc (mARC) treatment techniques. The mARC treatment plans for non-small-cell lung cancer (NSCLC) patients were made in order to verify the clinical usefulness of mARC. A pre-study was conducted to find the best plan condition for mARC treatment, and the usefulness of the mARC treatment plan was evaluated by comparing it with other Arc treatment plans such as tomotherapy and RapidArc plans. In the case of mARC, the optimal condition for the mARC plan was determined by comparing the dosimetric performance of the mARC plans developed by using various parameters, which included the photon energy (6 MV, 10 MV), the optimization point angle (6°- 10°intervals), and the total number of segments (36 - 59 segments). The best dosimetric performance of mARC was observed at a 10 MV photon energy, a point angle 6 degrees, and 59 segments. The treatment plans for the three different techniques were compared by using the following parameters: the conformity index (CI), homogeneity index (HI), the target coverage, the dose to the OARs, the number of monitor units (MU), the beam on time, and the normal tissue complication probability (NTCP). As a result, the three different treatment techniques showed similar target coverages. The mARC plan had the lowest V20 (volume of lung receiving > 20 Gy) and MU per fraction compared with both the RapidArc and the tomotherapy plans. The mARC plan reduced the beam on time as well. Therefore, the results of this study provide satisfactory evidence that the mARC technique can be considered as a useful clinical technique for radiation treatment.

Effects of megavoltage computed tomographic scan methodology on setup verification and adaptive dose calculation in helical TomoTherapy.

PubMed

Zhu, Jian; Bai, Tong; Gu, Jiabing; Sun, Ziwen; Wei, Yumei; Li, Baosheng; Yin, Yong

2018-04-27

To evaluate the effect of pretreatment megavoltage computed tomographic (MVCT) scan methodology on setup verification and adaptive dose calculation in helical TomoTherapy. Both anthropomorphic heterogeneous chest and pelvic phantoms were planned with virtual targets by TomoTherapy Physicist Station and were scanned with TomoTherapy megavoltage image-guided radiotherapy (IGRT) system consisted of six groups of options: three different acquisition pitches (APs) of 'fine', 'normal' and 'coarse' were implemented by multiplying 2 different corresponding reconstruction intervals (RIs). In order to mimic patient setup variations, each phantom was shifted 5 mm away manually in three orthogonal directions respectively. The effect of MVCT scan options was analyzed in image quality (CT number and noise), adaptive dose calculation deviations and positional correction variations. MVCT scanning time with pitch of 'fine' was approximately twice of 'normal' and 3 times more than 'coarse' setting, all which will not be affected by different RIs. MVCT with different APs delivered almost identical CT numbers and image noise inside 7 selected regions with various densities. DVH curves from adaptive dose calculation with serial MVCT images acquired by varied pitches overlapped together, where as there are no significant difference in all p values of intercept & slope of emulational spinal cord (p = 0.761 & 0.277), heart (p = 0.984 & 0.978), lungs (p = 0.992 & 0.980), soft tissue (p = 0.319 & 0.951) and bony structures (p = 0.960 & 0.929) between the most elaborated and the roughest serials of MVCT. Furthermore, gamma index analysis shown that, compared to the dose distribution calculated on MVCT of 'fine', only 0.2% or 1.1% of the points analyzed on MVCT of 'normal' or 'coarse' do not meet the defined gamma criterion. On chest phantom, all registration errors larger than 1 mm appeared at superior-inferior axis, which cannot be avoided with the smallest AP and RI. On pelvic phantom, craniocaudal errors are much smaller than chest, however, AP of 'coarse' presents larger registration errors which can be reduced from 2.90 mm to 0.22 mm by registration technique of 'full image'. AP of 'coarse' with RI of 6 mm is recommended in adaptive radiotherapy (ART) planning to provide craniocaudal longer and faster MVCT scan, while registration technique of 'full image' should be used to avoid large residual error. Considering the trade-off between IGRT and ART, AP of 'normal' with RI of 2 mm was highly recommended in daily practice.

Comparison of linac-based fractionated stereotactic radiotherapy and tomotherapy treatment plans for intra-cranial tumors

NASA Astrophysics Data System (ADS)

Jang, Bo Shim; Suk, Lee; Sam, Ju Cho; Sang, Hoon Lee; Juree, Kim; Kwang, Hwan Cho; Chul, Kee Min; Hyun Do, Huh; Rena, Lee; Dae, Sik Yang; Young, Je Park; Won, Seob Yoon; Chul, Yong Kim; Soo, Il Kwon

2010-11-01

This study compares and analyzes stereotactic radiotherapy using tomotherapy and linac-based fractionated stereotactic radiotherapy in the treatment of intra-cranial tumors, according to some cases. In this study, linac-based fractionated stereotactic radiotherapy and tomotherapy treatment were administered to five patients diagnosed with intra-cranial cancer in which the dose of 18-20 Gy was applied on 3-5 separate occasions. The tumor dosing was decided by evaluating the inhomogeneous index (II) and conformity index (CI). Also, the radiation-sensitive tissue was evaluated using low dose factors V1, V2, V3, V4, V5, and V10, as well as the non-irradiation ratio volume (NIV). The values of the II for each prescription dose in the linac-based non-coplanar radiotherapy plan and tomotherapy treatment plan were (0.125±0.113) and (0.090±0.180), respectively, and the values of the CI were (0.899±0.149) and (0.917±0.114), respectively. The low dose areas, V1, V2, V3, V4, V5, and V10, in radiation-sensitive tissues in the linac-based non-coplanar radiotherapy plan fell into the ranges 0.3%-95.6%, 0.1%-87.6%, 0.1%-78.8%, 38.8%-69.9%, 26.6%-65.2%, and 4.2%-39.7%, respectively, and the tomotherapy treatment plan had ranges of 13.6%-100%, 3.5%-100%, 0.4%-94.9%, 0.2%-82.2%, 0.1%-78.5%, and 0.3%-46.3%, respectively. Regarding the NIV for each organ, it is possible to obtain similar values except for the irradiation area of the brain stem. The percentages of NIV 10%, NIV20%, and NIV30%for the brain stem in each patient were 15%-99.8%, 33.4%-100%, and 39.8%-100%, respectively, in the fractionated stereotactic treatment plan and 44.2%-96.5%, 77.7%-99.8%, and 87.8%-100%, respectively, in the tomotherapy treatment plan. In order to achieve higher-quality treatment of intra-cranial tumors, treatment plans should be tailored according to the isodose target volume, inhomogeneous index, conformity index, position of the tumor upon fractionated stereotactic radiosurgery, and radiation dosage for radiation-sensitive tissues.

A feasibility study using TomoDirect for craniospinal irradiation

PubMed Central

Molloy, Janelle A.; Gleason, John F.; Feddock, Jonathan M.

2013-01-01

The feasibility of delivering craniospinal irradiation (CSI) with TomoDirect is investigated. A method is proposed to generate TomoDirect plans using standard three‐dimensional (3D) beam arrangements on Tomotherapy with junctioning of these fields to minimize hot or cold spots at the cranial/spinal junction. These plans are evaluated and compared to a helical Tomotherapy and a three‐dimensional conformal therapy (3D CRT) plan delivered on a conventional linear accelerator (linac) for CSI. The comparison shows that a TomoDirect plan with an overlap between the cranial and spinal fields might be preferable over Tomotherapy plans because of decreased low dose to large volumes of normal tissues outside of the planning target volume (PTV). Although the TomoDirect plans were not dosimetrically superior to a 3D CRT linac plan, the patient can be easily treated in the supine position, which is often more comfortable and efficient from an anesthesia standpoint. TomoDirect plans also have only one setup position which obviates the need for matching of fields and feathering of junctions, two issues encountered with conventional 3D CRT plans. TomoDirect plans can be delivered with comparable treatment times to conventional 3D plans and in shorter times than a Tomotherapy plan. In this paper, a method is proposed for creating TomoDirect craniospinal plans, and the dosimetric consequences for choosing different planning parameters are discussed. PACS number: 87.55.D‐ PMID:24036863

Evaluation of image-guided helical tomotherapy for the retreatment of spinal metastasis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mahan, Stephen L.; Ramsey, Chester R.; Scaperoth, Daniel D.

Introduction: Patients with vertebral metastasis that receive radiation therapy are typically treated to the spinal cord tolerance dose. As such, it is difficult to successfully deliver a second course of radiation therapy for patients with overlapping treatment volumes. In this study, an image-guided helical tomotherapy system was evaluated for the retreatment of previously irradiated vertebral metastasis. Methods and Materials: Helical tomotherapy dose gradients and maximum cord doses were measured in a cylindrical phantom for geometric test cases with separations between the planning target volume (PTV) and the spinal cord organ at risk (OAR) of 2 mm, 4 mm, 6 mm,more » 8 mm, and 10 mm. Megavoltage computed tomography (CT) images were examined for their ability to localize spinal anatomy for positioning purposes by repeat imaging of the cervical spine in an anthropomorphic phantom. In addition to the phantom studies, 8 patients with cord compressions that had received previous radiation therapy were retreated to a mean dose of 28 Gy using conventional fractionation. Results and Discussion: Megavoltage CT images were capable of positioning an anthropomorphic phantom to within {+-}1.2 mm (2{sigma}) superior-inferiorly and within {+-}0.6 mm (2{sigma}) anterior-posteriorly and laterally. Dose gradients of 10% per mm were measured in phantom while PTV uniformity indices of less than 11% were maintained. The calculated maximum cord dose was 25% of the prescribed dose for a 10-mm PTV-to-OAR separation and 71% of the prescribed dose for a PTV-to-OAR separation of 2 mm. Eight patients total have been treated without radiation-induced myelopathy or any other adverse effects from treatment. Conclusions: A technique has been evaluated for the retreatment of vertebral metastasis using image-guided helical tomotherapy. Phantom and patient studies indicated that a tomotherapy system is capable of delivering dose gradients of 10% per mm and positioning the patient within 1.2 mm without the use of special stereotactic immobilization.« less

SU-G-BRA-14: Dose in a Rigidly Moving Phantom with Jaw and MLC Compensation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chao, E; Lucas, D

Purpose: To validate dose calculation for a rigidly moving object with jaw motion and MLC shifts to compensate for the motion in a TomoTherapy™ treatment delivery. Methods: An off-line version of the TomoTherapy dose calculator was extended to perform dose calculations for rigidly moving objects. A variety of motion traces were added to treatment delivery plans, along with corresponding jaw compensation and MLC shift compensation profiles. Jaw compensation profiles were calculated by shifting the jaws such that the center of the treatment beam moved by an amount equal to the motion in the longitudinal direction. Similarly, MLC compensation profiles weremore » calculated by shifting the MLC leaves by an amount that most closely matched the motion in the transverse direction. The same jaw and MLC compensation profiles were used during simulated treatment deliveries on a TomoTherapy system, and film measurements were obtained in a rigidly moving phantom. Results: The off-line TomoTherapy dose calculator accurately predicted dose profiles for a rigidly moving phantom along with jaw motion and MLC shifts to compensate for the motion. Calculations matched film measurements to within 2%/1 mm. Jaw and MLC compensation substantially reduced the discrepancy between the delivered dose distribution and the calculated dose with no motion. For axial motion, the compensated dose matched the no-motion dose within 2%/1mm. For transverse motion, the dose matched within 2%/3mm (approximately half the width of an MLC leaf). Conclusion: The off-line TomoTherapy dose calculator accurately computes dose delivered to a rigidly moving object, and accurately models the impact of moving the jaws and shifting the MLC leaf patterns to compensate for the motion. Jaw tracking and MLC leaf shifting can effectively compensate for the dosimetric impact of motion during a TomoTherapy treatment delivery.« less

Magnetic tracking for TomoTherapy systems: gradiometer based methods to filter eddy-current magnetic fields.

PubMed

McGary, John E; Xiong, Zubiao; Chen, Ji

2013-07-01

TomoTherapy systems lack real-time, tumor tracking. A possible solution is to use electromagnetic markers; however, eddy-current magnetic fields generated in response to a magnetic source can be comparable to the signal, thus degrading the localization accuracy. Therefore, the tracking system must be designed to account for the eddy fields created along the inner bore conducting surfaces. The aim of this work is to investigate localization accuracy using magnetic field gradients to determine feasibility toward TomoTherapy applications. Electromagnetic models are used to simulate magnetic fields created by a source and its simultaneous generation of eddy currents within a conducting cylinder. The source position is calculated using a least-squares fit of simulated sensor data using the dipole equation as the model equation. To account for field gradients across the sensor area (≈ 25 cm(2)), an iterative method is used to estimate the magnetic field at the sensor center. Spatial gradients are calculated with two arrays of uniaxial, paired sensors that form a gradiometer array, where the sensors are considered ideal. Experimental measurements of magnetic fields within the TomoTherapy bore are shown to be 1%-10% less than calculated with the electromagnetic model. Localization results using a 5 × 5 array of gradiometers are, in general, 2-4 times more accurate than a planar array of sensors, depending on the solenoid orientation and position. Simulation results show that the localization accuracy using a gradiometer array is within 1.3 mm over a distance of 20 cm from the array plane. In comparison, localization errors using single array are within 5 mm. The results indicate that the gradiometer method merits further studies and work due to the accuracy achieved with ideal sensors. Future studies should include realistic sensor models and extensive numerical studies to estimate the expected magnetic tracking accuracy within a TomoTherapy system before proceeding with prototype development.

Xerostomia in patients treated for oropharyngeal carcinoma: comparing linear accelerator-based intensity-modulated radiation therapy with helical tomotherapy.

PubMed

Fortin, Israël; Fortin, Bernard; Lambert, Louise; Clavel, Sébastien; Alizadeh, Moein; Filion, Edith J; Soulières, Denis; Bélair, Manon; Guertin, Louis; Nguyen-Tan, Phuc Felix

2014-09-01

In comparison to sliding-window intensity-modulated radiation therapy (sw-IMRT), we hypothesized that helical tomotherapy (HT) would achieve similar locoregional control and, at the same time, decrease the parotid gland dose, thus leading to a xerostomia reduction. The association between radiation techniques, mean parotid dose, and xerostomia incidence, was reviewed in 119 patients with advanced oropharyngeal carcinoma treated with concurrent chemoradiation using sw-IMRT (n = 59) or HT (n = 60). Ipsilateral and contralateral parotid mean doses were significantly lower for patients treated with HT versus sw-IMRT: 24 Gy versus 32 Gy ipsilaterally and 20 Gy versus 25 Gy contralaterally. The incidence of grade ≥2 xerostomia was significantly lower in the HT group than in the sw-IMRT group: 12% versus 78% at 6 months, 3% versus 51% at 12 months, and 0% versus 25% at 24 months. Total parotid mean dose <25 Gy was strongly associated to a lower incidence of grade ≥2 xerostomia at 6, 12, and 24 months. This retrospective series suggests that using HT can better spare the parotid glands while respecting quantitative analysis of normal tissue effects in the clinic (QUANTEC)'s criteria. Copyright © 2013 Wiley Periodicals, Inc.

[11C]choline-PET-guided helical tomotherapy and estramustine in a patient with pelvic-recurrent prostate cancer: local control and toxicity profile after 24 months.

PubMed

Alongi, Filippo; Schipani, Stefano; Samanes Gajate, Ana Maria; Rosso, Alberto; Cozzarini, Cesare; Fiorino, Claudio; Alongi, Pierpaolo; Picchio, Maria; Gianolli, Luigi; Messa, Cristina; Di Muzio, Nadia

2010-01-01

[11C]choline positron emission tomograhy can be useful to detect metastatic disease and to localize isolated lymph node relapse after primary treatment in case of prostate-specific antigen failure. In case of lymph node failure in prostate cancer patients, surgery or radiotherapy can be proposed with a curative intent. Some reports have suggested that radiotherapy could have a role in local control of oligometastatic lymph node disease. This is the first reported case of [11C]choline positron emission tomography-guided helical tomotherapy concomitant with estramustine for the treatment of pelvic-recurrent prostate cancer. At 24 months after the end of helical tomotherapy, prostate-specific antigen was undetectable and no late toxicities were recorded. A disease-free survival of 24 months, in the absence of any type of systemic therapy, is uncommon in metastatic prostate cancer. The therapeutic approach of the case report is discussed and a literature review on the issue is presented.

Preliminary Retrospective Analysis of Daily Tomotherapy Output Constancy Checks Using Statistical Process Control.

PubMed

Mezzenga, Emilio; D'Errico, Vincenzo; Sarnelli, Anna; Strigari, Lidia; Menghi, Enrico; Marcocci, Francesco; Bianchini, David; Benassi, Marcello

2016-01-01

The purpose of this study was to retrospectively evaluate the results from a Helical TomoTherapy Hi-Art treatment system relating to quality controls based on daily static and dynamic output checks using statistical process control methods. Individual value X-charts, exponentially weighted moving average charts, and process capability and acceptability indices were used to monitor the treatment system performance. Daily output values measured from January 2014 to January 2015 were considered. The results obtained showed that, although the process was in control, there was an out-of-control situation in the principal maintenance intervention for the treatment system. In particular, process capability indices showed a decreasing percentage of points in control which was, however, acceptable according to AAPM TG148 guidelines. Our findings underline the importance of restricting the acceptable range of daily output checks and suggest a future line of investigation for a detailed process control of daily output checks for the Helical TomoTherapy Hi-Art treatment system.

Adaptive Radiation Therapy for Localized Mesothelioma with Mediastinal Metastasis Using Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Renaud, James; Yartsev, Slav; Department of Oncology, University of Western Ontario, London, Ontario

2009-10-01

The purpose of this study was to compare 2 adaptive radiotherapy strategies with helical tomotherapy. A patient having mesothelioma with mediastinal nodes was treated using helical tomotherapy with pretreatment megavoltage CT (MVCT) imaging. Gross tumor volumes (GTVs) were outlined on every MVCT study. Two alternatives for adapting the treatment were investigated: (1) keeping the prescribed dose to the targets while reducing the dose to the OARs and (2) escalating the target dose while maintaining the original level of healthy tissue sparing. Intensity modulated radiotherapy (step-and-shoot IMRT) and 3D conformal radiotherapy (3DCRT) plans for the patient were generated and compared. Themore » primary lesion and nodal mass regressed by 16.2% and 32.5%, respectively. Adapted GTVs and reduced planning target volume (PTV) margins of 4 mm after 22 fractions decrease the planned mean lung dose by 19.4%. For dose escalation, the planned prescribed doses may be increased from 50.0 to 58.7 Gy in PTV{sub 1} and from 60.0 to 70.5 Gy in PTV{sub 2}. The step-and-shoot IMRT plan was better in sparing healthy tissue but did not provide target coverage as well as the helical tomotherapy plan. The 3DCRT plan resulted in a prohibitively high planned dose to the spinal cord. MVCT studies provide information both for setup correction and plan adaptation. Improved healthy tissue sparing and/or dose escalation can be achieved by adaptive planning.« less

A dosimetric comparison of 3D-CRT, IMRT, and static tomotherapy with an SIB for large and small breast volumes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Michalski, Andrea; Central Coast Cancer Centre, Gosford Hospital, Gosford, New South Wales; Atyeo, John, E-mail: john.atyeo@sydney.edu.au

2014-07-01

Radiation therapy to the breast is a complex task, with many different techniques that can be employed to ensure adequate dose target coverage while minimizing doses to the organs at risk. This study compares the dose planning outcomes of 3 radiation treatment modalities, 3 dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and static tomotherapy, for left-sided whole-breast radiation treatment with a simultaneous integrated boost (SIB). Overall, 20 patients with left-sided breast cancer were separated into 2 cohorts, small and large, based on breast volume. Dose plans were produced for each patient using 3D-CRT, IMRT, and static tomotherapy. Allmore » patients were prescribed a dose of 45 Gy in 20 fractions to the breast with an SIB of 56 Gy in 20 fractions to the tumor bed and normalized so that D{sub 98%} > 95% of the prescription dose. Dosimetric comparisons were made between the 3 modalities and the interaction of patient size. All 3 modalities offered adequate planning target volume (PTV) coverage with D{sub 98%} > 95% and D{sub 2%} < 107%. Static tomotherapy offered significantly improved (p = 0.006) dose homogeneity to the PTV{sub boost} {sub eval} (0.079 ± 0.011) and breast minus the SIB volume (Breast{sub SIB}) (p < 0.001, 0.15 ± 0.03) compared with the PTV{sub boost} {sub eval} (0.085 ± 0.008, 0.088 ± 0.12) and Breast{sub SIB} (0.22 ± 0.05, 0.23 ± 0.03) for IMRT and 3D-CRT, respectively. Static tomotherapy also offered statistically significant reductions (p < 0.001) in doses to the ipsilateral lung mean dose of 6.79 ± 2.11 Gy compared with 7.75 ± 2.54 Gy and 8.29 ± 2.76 Gy for IMRT and 3D-CRT, respectively, and significantly (p < 0.001) reduced heart doses (mean = 2.83 ± 1.26 Gy) compared to both IMRT and 3D-CRT (mean = 3.70 ± 1.44 Gy and 3.91 ± 1.58 Gy). Static tomotherapy is the dosimetrically superior modality for the whole breast with an SIB compared with IMRT and 3D-CRT. IMRT is superior to 3D-CRT in both PTV dose conformity and reduction of mean doses to the ipsilateral lung.« less

Beam commissioning and measurements validating the beam model in a new TPS that converts helical tomotherapy plans to step-and-shoot IMRT plans.

PubMed

Petersson, Kristoffer; Ceberg, Crister; Engström, Per; Knöös, Tommy

2011-01-01

A new type of treatment planning system called SHAREPLAN has been studied, which enables the transfer of treatment plans generated for helical tomotherapy delivery to plans that can be delivered on C-arm linacs. The purpose is to ensure continuous patient treatment during periods of unscheduled downtime for the TomoTherapy unit, particularly in clinics without a backup unit. The purpose of this work was to verify that the plans generated in this novel planning system are deliverable and accurate. The work consists primarily of beam commissioning, verification of the beam model, and measurements verifying that generated plans are deliverable with sufficient accuracy. The beam commissioning process involves input of general geometric properties of the modeled linac, profiles and depth dose curves for a specific photon nominal energy (6 MV), and the automated modeling of other beam properties. Some manual tuning of the beam model is required. To evaluate its accuracy, the confidence limit concept [J. Venselaar et al., "Tolerances for the accuracy of photon beam dose calculations of treatment planning systems," Radiother. Oncol. 60, 191-201 (2001)] was used, which is a method supported by ESTRO. Measurements were conducted with a 2D diode array at the commissioned linac as a final check of the beam model and to evaluate whether the generated plans were deliverable and accurate. The comparison and evaluation of calculated data points and measured data according to the method applied confirmed the accuracy of the beam model. The profiles had a confidence limit of 1.1% and the depth dose curves had a confidence limit of 1.7%, both of which were well below the tolerance limit of 2%. Plan specific QC measurements and evaluation verified that different plans generated in the TPS were deliverable with sufficient accuracy at the commissioned linac, as none of the 160 beams for the 20 different plans evaluated had a fraction of approved data points below 90%, the local clinical approval criterion for delivery QA measurements. This study is a validation of the new TPS as it verifies that the generated plans are deliverable at a commissioned linac with adequate accuracy. A thorough investigation of the treatment plan quality will require a separate study. The TPS is proving to be a useful and time-saving complement, especially for clinics having a single unit for helical delivery among its conventional linacs.

Helical tomotherapy with dynamic running-start-stop delivery compared to conventional tomotherapy delivery

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rong, Yi, E-mail: yi.rong@osumc.edu; Chen, Yu; Lu, Weiguo

Purpose: Despite superior target dose uniformity, helical tomotherapy{sup ®} (HT) may involve a trade-off between longitudinal dose conformity and beam-on time (BOT), due to the limitation of only three available jaw sizes with the conventional HT (1.0, 2.5, and 5.0 cm). The recently introduced dynamic running-start-stop (RSS) delivery allows smaller jaw opening at the superior and inferior ends of the target when a sharp penumbra is needed. This study compared the dosimetric performance of RSS delivery with the fixed jaw HT delivery. Methods: Twenty patient cases were selected and deidentified prior to treatment planning, including 16 common clinical cases (brain,more » head and neck (HN), lung, and prostate) and four special cases of whole brain with hippocampus avoidance (WBHA) that require a high degree of dose modulation. HT plans were generated for common clinical cases using the fixed 2.5 cm jaw width (HT2.5) and WBHA cases using 1.0 cm (HT1.0). The jaw widths for RSS were preset with a larger size (RSS5.0 vs HT2.5 and RSS2.5 vs HT1.0). Both delivery techniques were planned based on identical contours, prescriptions, and planning objectives. Dose indices for targets and critical organs were compared using dose-volume histograms, BOT, and monitor units. Results: The average BOT was reduced from 4.8 min with HT2.5 to 2.5 min with RSS5.0. Target dose homogeneity with RSS5.0 was shown comparable to HT2.5 for common clinical sites. Superior normal tissue sparing was observed in RSS5.0 for optic nerves and optic chiasm in brain and HN cases. RSS5.0 demonstrated improved dose sparing for cord and esophagus in lung cases, as well as penile bulb in prostate cases. The mean body dose was comparable for both techniques. For the WBHA cases, the target homogeneity was significantly degraded in RSS2.5 without distinct dose sparing for hippocampus, compared to HT1.0. Conclusions: Compared to the fixed jaw HT delivery, RSS combined with a larger jaw width provides faster treatment delivery and improved cranial-caudal target dose conformity. The target coverage achieved by RSS with a large jaw width is comparable to the fixed jaw HT delivery for common cancer sites, but may deteriorate for cases where complex geometry is present in the middle part of the target.« less

Image-guided total-marrow irradiation using helical tomotherapy in patients with multiple myeloma and acute leukemia undergoing hematopoietic cell transplantation.

PubMed

Wong, Jeffrey Y C; Rosenthal, Joseph; Liu, An; Schultheiss, Timothy; Forman, Stephen; Somlo, George

2009-01-01

Total-body irradiation (TBI) has an important role in patients undergoing hematopoietic cell transplantation (HCT), but is associated with significant toxicities. Targeted TBI using helical tomotherapy results in reduced doses to normal organs, which predicts for reduced toxicities compared with standard TBI. Thirteen patients with multiple myeloma were treated in an autologous tandem transplantation Phase I trial with high-dose melphalan, followed 6 weeks later by total-marrow irradiation (TMI) to skeletal bone. Dose levels were 10, 12, 14, and 16 Gy at 2 Gy daily/twice daily. In a separate allogeneic HCT trial, 8 patients (5 with acute myelogenous leukemia, 1 with acute lymphoblastic leukemia, 1 with non-Hodgkin's lymphoma, and 1 with multiple myeloma) were treated with TMI plus total lymphoid irradiation plus splenic radiotherapy to 12 Gy (1.5 Gy twice daily) combined with fludarabine/melphalan. For the 13 patients in the tandem autologous HCT trial, median age was 54 years (range, 42-66 years). Median organ doses were 15-65% that of the gross target volume dose. Primarily Grades 1-2 acute toxicities were observed. Six patients reported no vomiting; 9 patients, no mucositis; 6 patients, no fatigue; and 8 patients, no diarrhea. For the 8 patients in the allogeneic HCT trial, median age was 52 years (range, 24-61 years). Grades 2-3 nausea, vomiting, mucositis, and diarrhea were observed. In both trials, no Grade 4 nonhematologic toxicity was observed, and all patients underwent successful engraftment. This study shows that TMI using helical tomotherapy is clinically feasible. The reduced acute toxicities observed compare favorably with those seen with standard TBI. Initial results are encouraging and warrant further evaluation as a method to dose escalate with acceptable toxicity or to offer TBI-containing regimens to patients unable to tolerate standard approaches.

SU-E-T-197: Helical Cranial-Spinal Treatments with a Linear Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, J; Bernard, D; Liao, Y

2014-06-01

Purpose: Craniospinal irradiation (CSI) of systemic disease requires a high level of beam intensity modulation to reduce dose to bone marrow and other critical structures. Current helical delivery machines can take 30 minutes or more of beam-on time to complete these treatments. This pilot study aims to test the feasibility of performing helical treatments with a conventional linear accelerator using longitudinal couch travel during multiple gantry revolutions. Methods: The VMAT optimization package of the Eclipse 10.0 treatment planning system was used to optimize pseudo-helical CSI plans of 5 clinical patient scans. Each gantry revolution was divided into three 120° arcsmore » with each isocenter shifted longitudinally. Treatments requiring more than the maximum 10 arcs used multiple plans with each plan after the first being optimized including the dose of the others (Figure 1). The beam pitch was varied between 0.2 and 0.9 (couch speed 5- 20cm/revolution and field width of 22cm) and dose-volume histograms of critical organs were compared to tomotherapy plans. Results: Viable pseudo-helical plans were achieved using Eclipse. Decreasing the pitch from 0.9 to 0.2 lowered the maximum lens dose by 40%, the mean bone marrow dose by 2.1% and the maximum esophagus dose by 17.5%. (Figure 2). Linac-based helical plans showed dose results comparable to tomotherapy delivery for both target coverage and critical organ sparing, with the D50 of bone marrow and esophagus respectively 12% and 31% lower in the helical linear accelerator plan (Figure 3). Total mean beam-on time for the linear accelerator plan was 8.3 minutes, 54% faster than the tomotherapy average for the same plans. Conclusions: This pilot study has demonstrated the feasibility of planning pseudo-helical treatments for CSI targets using a conventional linac and dynamic couch movement, and supports the ongoing development of true helical optimization and delivery.« less

A method to incorporate leakage and head scatter corrections into a tomotherapy inverse treatment planning algorithm

NASA Astrophysics Data System (ADS)

Holmes, Timothy W.

2001-01-01

A detailed tomotherapy inverse treatment planning method is described which incorporates leakage and head scatter corrections during each iteration of the optimization process, allowing these effects to be directly accounted for in the optimized dose distribution. It is shown that the conventional inverse planning method for optimizing incident intensity can be extended to include a `concurrent' leaf sequencing operation from which the leakage and head scatter corrections are determined. The method is demonstrated using the steepest-descent optimization technique with constant step size and a least-squared error objective. The method was implemented using the MATLAB scientific programming environment and its feasibility demonstrated for 2D test cases simulating treatment delivery using a single coplanar rotation. The results indicate that this modification does not significantly affect convergence of the intensity optimization method when exposure times of individual leaves are stratified to a large number of levels (>100) during leaf sequencing. In general, the addition of aperture dependent corrections, especially `head scatter', reduces incident fluence in local regions of the modulated fan beam, resulting in increased exposure times for individual collimator leaves. These local variations can result in 5% or greater local variation in the optimized dose distribution compared to the uncorrected case. The overall efficiency of the modified intensity optimization algorithm is comparable to that of the original unmodified case.

SU-E-J-172: Development of a Video Guided Real-Time Patient Motion Monitoring System for Helical Tomotherpay.

PubMed

Ju, S; Hong, C; Yim, D; Kim, M; Kim, J; Han, Y; Shin, J; Shin, E; Ahn, S; Choi, D

2012-06-01

We developed a video image-guided real-time patient motion monitoring system for helical Tomotherapy (VGRPM-Tomo), and its clinical utility was evaluated using a motion phantom. The VGRPM-Tomo consisted of three components: an image acquisition device consisting of two PC-cams, a main control computer with a radiation signal controller and warning system, and patient motion analysis software, which was developed in house. The system was designed for synchronization with a beam on/off trigger signal to limit operation during treatment time only and to enable system automation. In order to detect the patient motion while the couch is moving into the gantry, a reference image, which continuously updated its background by exponential weighting filter (EWF), is compared with subsequent live images using the real-time frame difference-based analysis software. When the error range exceeds the set criteria (δ_movement) due to patient movement, a warning message is generated in the form of light and sound. The described procedure repeats automatically for each patient. A motion phantom, which operates by moving a distance of 0.1, 0.2, 0.5, and 1.0 cm for 1 and 2 sec, respectively, was used to evaluate the system performance at maximum couch speed (0.196 cm/sec) in a Helical Tomotherapy (HD, Hi-art, Tomotherapy, USA). We measured the optimal EWF factor (a) and δ_movement, which is the minimum distance that can be detected with this system, and the response time of the whole system. The optimal a for clinical use ranged from 0.85 to 0.9. The system was able to detect phantom motion as small as 0.2 cm with tight δ_movement, 0.1% total number of pixels in the reference image. The measured response time of the whole system was 0.1 sec. The VGRPM-tomo can contribute to reduction of treatment error caused by the motion of patients and increase the accuracy of treatment dose delivery in HD. This work was supported by the Technology Innovation Program, 10040362, Development of an integrated management solution for radiation therapy funded by the Ministry of Knowledge Economy (MKE, Korea). This idea is protected by a Korean patent (patent no. 10-1007367). © 2012 American Association of Physicists in Medicine.

SU-F-T-27: A Comparative Case Study Among Four Modalities for the Superficial Treatment of Squamous Cell Carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ashenafi, M; Koch, N; Peng, J

Purpose: We performed a comparative planning study among High Dose Rate (HDR) brachytherapy, superficial electrons, Volume Modulated Arc Therapy (VMAT), and Helical IMRT (Tomotherapy) for squamous cell carcinoma of the abdominal wall with consideration for the underlining bowel. Methods: A 69-year old female presented with squamous cell carcinoma protruding 8mm beyond the anterior skin surface of the midabdomen was considered for treatment. The patient had a ventral hernia which resulted in the reduction of the abdominal wall thickness and the adjacent small bowel being the dose limiting structure. Four plans were generated using different treatment modalities: a) an enface electronmore » field (eMC, Eclipse v. 11), b) Tomotherapy (HI-Art II v.5.0.5), c) VMAT (Acuros, Eclipse v. 11), and d) HDR using a Freiburg applicator (Oncentra v. 4.3). The following plan objectives were used for all four plans: for the CTV target, V90% ≥90% (61.8Gy2/2).For the small bowel, D0.1cc < 56.2 Gy2/2 was a hard constraint and expressed as a percentage of the prescription for comparison to demonstrate the dose fall-off achieved among the modalities.For HDR, V200% <0.1cc was an additional constraint. Multiple dosimetric parameters, including those listed above, were compared among the four modalities. Results: The HDR plan showed comparable target coverage compared to the Tomotherapy plan and better coverage compared to the electron plan. Small bowel doses (D0.1cc) were lower in HDR plan compared to Tomotherapy, electron, & VMAT plans (88.8%, 89.6%, 90.9%, & 96.6%). Integral dose to the whole body (V5%) was much higher for HDR, VMAT, and Tomotherapy when compared to electron plan by factors of seven, eight, and ten, respectively. After reviewing all treatment modalities, the physician selected HDR owing to better control of the small bowel dose while maintaining adequate target coverage. Conclusion: This case study demonstrated HDR can successfully treat superficial lesions with superior sparing of underlying structures.« less

SU-E-T-581: Planning Evaluation of Step-And-Shoot IMRT, RapidArc and Helical TomoTherapy for Hippocampal-Avoidance Whole Brain Radiotherapy (HA-WBRT).

PubMed

Evans, J; Chen, Q; Wuthrick, E; Weldon, M; Rong, Y

2012-06-01

Several planning strategies are available for hippocampal- avoidance whole-brain radiotherapy (HA-WBRT) following RTOG protocol 0933, but have yet to be compared on a common set of patient data. In this inter-institutional investigation, we evaluate three modalities likely to be employed by protocol participants; step-and-shoot IMRT, volumetric modulated arc therapy, and helical tomotherapy. A common set of patients is used for comparison, including credentialing and successfully accrued patients. Eight patient datasets were selected and de-identified prior to planning. Structures were contoured by physicians per protocol using fused MRI datasets. Three plans were generated for each dataset: Philips Pinnacle 9-field non-coplanar IMRT using protocol recommended beam parameters, Varian's RapidArc using two coplanar arcs, and Accuray's TomoTherapy using a 1cm jaw width. With the goal of meeting the compliance criteria outlined in RTOG 0933 (target coverage and dose limits to the hippocampus and optic structures), three planners independently planned each modality without prior knowledge of the patient's other plans to reduce bias. The three plans for each patient were compared according to the protocol's dosimetric compliance criteria. A homogeneity index was also computed to compare target dose uniformity. All plans achieved the protocol dose criteria, except for one RapidArc plan with slightly inferior dose to the optic chiasm. TomoTherapy offered superior dose homogeneity for all patients. For the two linac based methods, RapidArc was found to provide dose homogeneity at least as good as, and in most cases superior to, 9-field step-and-shoot IMRT. Helical TomoTherapy offers superior dose homogeneity for HA-WBRT following RTOG 0933. Compared to step-and-shoot IMRT, volumetric modulated arc techniques, such as RapidArc, can offer improved homogeneity for HA- WBRT and are generally more efficient/expeditious to deliver than the noncoplanar 9-field arrangement recommended by the protocol, which uses 7 separate couch angles. © 2012 American Association of Physicists in Medicine.

Parotid Gland Sparing With Helical Tomotherapy in Head-and-Neck Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Voordeckers, Mia, E-mail: mia.voordeckers@uzbrussel.be; Farrag, Ashraf; Assiut University

Purpose: This study evaluated the ability of helical tomotherapy to spare the function of the parotid glands in patients with head-and-neck cancer by analyzing dose-volume histograms, salivary gland scintigraphy, and quality of life assessment. Methods and Materials: Data from 76 consecutive patients treated with helical tomotherapy (Hi-Art Tomotherapy) at University Hospital Brussel were analyzed. During planning, priority was given to planning target volume (PTV) coverage: {>=}95% of the dose must be delivered to {>=}95% of the PTV. Elective nodal regions received 54 Gy (1.8 Gy/fraction). A dose of 70.5 Gy (2.35 Gy/fraction) was prescribed to the primary tumor and pathologicmore » lymph nodes (simultaneous integrated boost scheme). Objective scoring of salivary excretion was performed by salivary gland scintigraphy. Subjective scoring of salivary gland function was evaluated by the European Organization for Research and Treatment of Cancer quality of life questionnaires Quality of Life Questionnaire-C30 (QLQ-C30) and Quality of Life Questionnaire-Head and Neck 35 (H and N35). Results: Analysis of dose-volume histograms (DVHs) showed excellent coverage of the PTV. The volume of PTV receiving 95% of the prescribed dose (V95%) was 99.4 (range, 96.3-99.9). DVH analysis of parotid gland showed a median value of the mean parotid dose of 32.1 Gy (range, 17.5-70.3 Gy). The median parotid volume receiving a dose <26 Gy was 51.2%. Quality of life evaluation demonstrated an initial deterioration of almost all scales and items in QLQ-C30 and QLQ-H and N35. Most items improved in time, and some reached baseline values 18 months after treatment. Conclusion: DVH analysis, scintigraphic evaluation of parotid function, and quality of life assessment of our patient group showed that helical tomotherapy makes it possible to preserve parotid gland function without compromising disease control. We recommend mean parotid doses of <34 Gy and doses <26 Gy to a maximum 47% of the parotid volume as planning goals. Intensity-modulated radiotherapy should be considered as standard treatment in patients with head-and-neck cancer.« less

Use of tomotherapy in treatment of synchronous bilateral breast cancer: dosimetric comparison study

PubMed Central

Wadasadawala, T; Sarin, R; Upreti, R R; Paul, S; Phurailatpam, R

2015-01-01

Objective: Synchronous malignancy in both breasts is a rare incidence. The present study aims at dosimetric comparison of conventional bitangential radiotherapy (RT) technique with conventional [field-in-field (FIF)] and rotational [Helical TomoTherapy® and TomoDirect™ (TD); Accuray Inc., Sunnyvale, CA] intensity-modulated RT for patients with synchronous bilateral breast cancer (SBBC). Methods: CT data sets of 10 patients with SBBC were selected for the present study. RT was planned for all patients on both sides to whole breast and/or chest wall using the above-mentioned techniques. Six females with breast conservation on at least one side also had a composite plan along with tumour bed (TB) boost using sequential electrons for bitangential and FIF techniques or sequential helical tomotherapy (HT) boost (for TD) or simultaneous integrated boost (SIB) for HT. Results: All techniques produced acceptable target coverage. The hotspot was significantly lower with FIF technique and HT but higher with TD. For the organs at risk doses, HT resulted in significant reduction of the higher dose volumes. Similarly, TD resulted in significant reduction of the mean dose to the heart and total lung by reducing the lower dose volumes. All techniques of delivering boost to the TB were comparable in terms of target coverage. HT-SIB markedly reduced mean doses to the total lung and heart by specifically lowering the higher dose volumes. Conclusion: This study demonstrates the cardiac and pulmonary sparing ability of tomotherapy in the setting of SBBC. Advances in knowledge: This is the first study demonstrating feasibility of treatment of SBBC using tomotherapy. PMID:25605345

Impact of the Lok-bar for High-precision Radiotherapy with Tomotherapy.

PubMed

Hirata, Makoto; Monzen, Hajime; Tamura, Mikoto; Kubo, Kazuki; Matsumoto, Kenji; Hanaoka, Kohei; Okumura, Masahiko; Nishimura, Yasumasa

2018-05-01

Patient immobilization systems are used to establish a reproducible patient position relative to the couch. In this study, the impact of conventional lok-bars for CT-simulation (CIVCO-bar) and treatment (iBEAM-bar) were compared with a novel lok-bar (mHM-bar) in tomotherapy. Verification was obtained as follows: i. artifacts in CT images; ii. dose attenuation rate of lok-bar, compared to without lok-bar; and iii. dose differences between the calculated and measured absorbed doses. With the CIVCO-bar, there were obvious metal artifacts, while there were nearly no artifacts with the mHM-bar. The mean dose attenuation rates with the mHM-bar and iBEAM-bar were 1.31% and 2.28%, and the mean dose difference was 1.55% and 1.66% for mHM-bar and iBEAM-bar. Using the mHM-bar reduced artifacts on the CT image and improved dose attenuation are obtained. The lok-bar needs to be inserted as a structure set in treatment planning with tomotherapy. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klüter, Sebastian, E-mail: sebastian.klueter@med.uni-heidelberg.de; Schubert, Kai; Lissner, Steffen

Purpose: The dosimetric verification of treatment plans in helical tomotherapy usually is carried out via verification measurements. In this study, a method for independent dose calculation of tomotherapy treatment plans is presented, that uses a conventional treatment planning system with a pencil kernel dose calculation algorithm for generation of verification dose distributions based on patient CT data. Methods: A pencil beam algorithm that directly uses measured beam data was configured for dose calculation for a tomotherapy machine. Tomotherapy treatment plans were converted into a format readable by an in-house treatment planning system by assigning each projection to one static treatmentmore » field and shifting the calculation isocenter for each field in order to account for the couch movement. The modulation of the fluence for each projection is read out of the delivery sinogram, and with the kernel-based dose calculation, this information can directly be used for dose calculation without the need for decomposition of the sinogram. The sinogram values are only corrected for leaf output and leaf latency. Using the converted treatment plans, dose was recalculated with the independent treatment planning system. Multiple treatment plans ranging from simple static fields to real patient treatment plans were calculated using the new approach and either compared to actual measurements or the 3D dose distribution calculated by the tomotherapy treatment planning system. In addition, dose–volume histograms were calculated for the patient plans. Results: Except for minor deviations at the maximum field size, the pencil beam dose calculation for static beams agreed with measurements in a water tank within 2%/2 mm. A mean deviation to point dose measurements in the cheese phantom of 0.89% ± 0.81% was found for unmodulated helical plans. A mean voxel-based deviation of −0.67% ± 1.11% for all voxels in the respective high dose region (dose values >80%), and a mean local voxel-based deviation of −2.41% ± 0.75% for all voxels with dose values >20% were found for 11 modulated plans in the cheese phantom. Averaged over nine patient plans, the deviations amounted to −0.14% ± 1.97% (voxels >80%) and −0.95% ± 2.27% (>20%, local deviations). For a lung case, mean voxel-based deviations of more than 4% were found, while for all other patient plans, all mean voxel-based deviations were within ±2.4%. Conclusions: The presented method is suitable for independent dose calculation for helical tomotherapy within the known limitations of the pencil beam algorithm. It can serve as verification of the primary dose calculation and thereby reduce the need for time-consuming measurements. By using the patient anatomy and generating full 3D dose data, and combined with measurements of additional machine parameters, it can substantially contribute to overall patient safety.« less

Dose-volume effects for pelvic bone marrow in predicting hematological toxicity in prostate cancer radiotherapy with pelvic node irradiation.

PubMed

Sini, Carla; Fiorino, Claudio; Perna, Lucia; Noris Chiorda, Barbara; Deantoni, Chiara Lucrezia; Bianchi, Marco; Sacco, Vincenzo; Briganti, Alberto; Montorsi, Francesco; Calandrino, Riccardo; Di Muzio, Nadia; Cozzarini, Cesare

2016-01-01

To prospectively identify clinical/dosimetric predictors of acute/late hematologic toxicity (HT) in chemo-naÏve patients treated with whole-pelvis radiotherapy (WPRT) for prostate cancer. Data of 121 patients treated with adjuvant/salvage WPRT were analyzed (static-field IMRT n=19; VMAT/Rapidarc n=57; Tomotherapy n=45). Pelvic bone marrow (BM) was delineated as ilium (IL), lumbosacral, lower and whole pelvis (WP), and the relative DVHs were calculated. HT was graded both according to CTCAE v4.03 and as variation in percentage relative to baseline. Logistic regression was used to analyze association between HT and clinical/DVHs factors. Significant differences (p<0.005) in the DVH of BM volumes between different techniques were found: Tomotherapy was associated with larger volumes receiving low doses (3-20 Gy) and smaller receiving 40-50 Gy. Lower baseline absolute values of WBC, neutrophils and lymphocytes (ALC) predicted acute/late HT (p ⩽ 0.001). Higher BM V40 was associated with higher risk of acute Grade3 (OR=1.018) or late Grade2 lymphopenia (OR=1.005). Two models predicting lymphopenia were developed, both including baseline ALC, and BM WP-V40 (AUC=0.73) and IL-V40+smoking (AUC=0.904) for acute/late respectively. Specific regions of pelvic BM predicting acute/late lymphopenia, a risk factor for viral infections, were identified. The 2-variable models including specific constraints to BM may help reduce HT. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thiyagarajan, Rajesh; Karrthick, KP; Kataria, Tejinder

Purpose: Performing DQA for Bilateral (B-L) breast tomotherapy is a challenging task due to the limitation of any commercially available detector array or film. Aim of this study is to perform DQA for B-L breast tomotherapy plan using MLC fluence sinogram. Methods: Treatment plan was generated on Tomotherapy system for B-L breast tumour. B-L breast targets were given 50.4 Gy prescribed over 28 fractions. Plan is generated with 6 MV photon beam & pitch was set to 0.3. As the width of the total target is 39 cm (left & right) length is 20 cm. DQA plan delivered without anymore » phantom on the mega voltage computed tomography (MCVT) detector system. The pulses recorded by MVCT system were exported to the delivery analysis software (Tomotherapy Inc.) for reconstruction. The detector signals are reconstructed to a sonogram and converted to MLC fluence sonogram. The MLC fluence sinogram compared with the planned fluence sinogram. Also point dose measured with cheese phantom and ionization chamber to verify the absolute dose component Results: Planned fluence sinogram and reconstructed MLC fluence sinogram were compared using Gamma metric. MLC positional difference and intensity of the beamlet were used as parameters to evaluate gamma. 3 mm positional difference and 3% beamlet intensity difference were used set for gamma calculation. A total of 26784 non-zero beamlets were included in the analysis out of which 161 beamlets had gamma more than 1. The gamma passing rate found to be 99.4%. Point dose measurements were within 1.3% of the calculated dose. Conclusion: MLC fluence sinogram based delivery quality assurance performed for bilateral breast irradiation. This would be a suitable alternate for large volume targets like bilateral breast, Total body irradiation etc. However conventional method of DQA should be used to validate this method periodically.« less

Treatment plan comparison of linac step and shoot, tomotherapy, rapidarc, and proton therapy for prostate cancer by using the dosimetrical and the biological indices

NASA Astrophysics Data System (ADS)

Lee, Suk; Cao, Yuan Jie; Chang, Kyung Hwan; Shim, Jang Bo; Kim, Kwang Hyeon; Lee, Nam Kwon; Park, Young Je; Kim, Chul Yong; Cho, Sam Ju; Lee, Sang Hoon; Min, Chul Kee; Kim, Woo Chul; Cho, Kwang Hwan; Huh, Hyun Do; Lim, Sangwook; Shin, Dongho

2015-07-01

The purpose of this study was to use various dosimetrical indices to determine the best intensitymodulated radiation therapy (IMRT) modality - for treating patients with prostate cancer. Ten patients with prostate cancer were included in this study. IMRT plans were designed to include different modalities, including the linac step and shoot, tomotherapy, RapidArc, and proton systems. Various dosimetrical indices, like the prescription isodose to target volume (PITV) ratio, conformity index (CI), homogeneity index (HI), target coverage index (TCI), modified dose homogeneity index (MHI), conformation number (CN), critical organ scoring index (COSI), and quality factor (QF), were determined to compare the different treatment plans. Biological indices, such as the generalized equivalent uniform dose (gEUD) based the tumor control probability (TCP), and the normal tissue complication probability (NTCP), were also calculated and used to compare the treatment plans. The RapidArc plan attained better PTV coverage, as evidenced by its superior PITV, CI, TCI, MHI, and CN values. Regarding organ at risks (OARs), proton therapy exhibited superior dose sparing for the rectum and the bowel in low dose volumes, whereas the tomotherapy and RapidArc plans achieved better dose sparing in high dose volumes. The QF scores showed no significant difference among these plans (p = 0.701). The average TCPs for prostate tumors in the RapidArc, linac and proton plans were higher than the average TCP for Tomotherapy (98.79%, 98.76%, and 98.75% vs. 98.70%, respectively). Regarding the rectum NTCP, RapidArc showed the most favorable result (0.09%) whereas linac resulted in the best bladder NTCP (0.08%).

A general method for the definition of margin recipes depending on the treatment technique applied in helical tomotherapy prostate plans.

PubMed

Sevillano, David; Mínguez, Cristina; Sánchez, Alicia; Sánchez-Reyes, Alberto

2016-01-01

To obtain specific margin recipes that take into account the dosimetric characteristics of the treatment plans used in a single institution. We obtained dose-population histograms (DPHs) of 20 helical tomotherapy treatment plans for prostate cancer by simulating the effects of different systematic errors (Σ) and random errors (σ) on these plans. We obtained dosimetric margins and margin reductions due to random errors (random margins) by fitting the theoretical results of coverages for Gaussian distributions with coverages of the planned D99% obtained from the DPHs. The dosimetric margins obtained for helical tomotherapy prostate treatments were 3.3 mm, 3 mm, and 1 mm in the lateral (Lat), anterior-posterior (AP), and superior-inferior (SI) directions. Random margins showed parabolic dependencies, yielding expressions of 0.16σ(2), 0.13σ(2), and 0.15σ(2) for the Lat, AP, and SI directions, respectively. When focusing on values up to σ = 5 mm, random margins could be fitted considering Gaussian penumbras with standard deviations (σp) equal to 4.5 mm Lat, 6 mm AP, and 5.5 mm SI. Despite complex dose distributions in helical tomotherapy treatment plans, we were able to simplify the behaviour of our plans against treatment errors to single values of dosimetric and random margins for each direction. These margins allowed us to develop specific margin recipes for the respective treatment technique. The method is general and could be used for any treatment technique provided that DPHs can be obtained. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Q; Read, P

Purpose: Multiple error pathways can lead to delivery errors during the treatment course that cannot be caught with pre-treatment QA. While in vivo solutions are being developed for linacs, no such solution exists for tomotherapy. The purpose of this study is to develop a near real-time system for tomotherapy that can monitor the delivery and dose accumulation process during the treatment-delivery, which enable the user to assess the impact of delivery variations and/or errors and to interrupt the treatment if necessary. Methods: A program running on a tomotherapy planning station fetches the raw DAS data during treatment. Exit detector datamore » is extracted as well as output, gantry angle, and other machine parameters. For each sample, the MLC open-close state is determined. The delivered plan is compared with the original plan via a Monte Carlo dose engine which transports fluence deviations from a pre-treatment Monte Carlo run. A report containing the difference in fluence, dose and DVH statistics is created in html format. This process is repeated until the treatment is completed. Results: Since we only need to compute the dose for the difference in fluence for a few projections each time, dose with 2% statistical uncertainty can be computed in less than 1 second on a 4-core cpu. However, the current bottleneck in this near real-time system is the repeated fetching and processing the growing DAS data file throughout the delivery. The frame rate drops from 10Hz at the beginning of treatment to 5Hz after 3 minutes and to 2Hz after 10 minutes. Conclusion: A during-treatment delivery monitor system has been built to monitor tomotherapy treatments. The system improves patient safety by allowing operators to assess the delivery variations and errors during treatment delivery and adopt appropriate actions.« less

SU-E-T-103: Development and Implementation of Web Based Quality Control Software

DOE Office of Scientific and Technical Information (OSTI.GOV)

Studinski, R; Taylor, R; Angers, C

Purpose: Historically many radiation medicine programs have maintained their Quality Control (QC) test results in paper records or Microsoft Excel worksheets. Both these approaches represent significant logistical challenges, and are not predisposed to data review and approval. It has been our group's aim to develop and implement web based software designed not just to record and store QC data in a centralized database, but to provide scheduling and data review tools to help manage a radiation therapy clinics Equipment Quality control program. Methods: The software was written in the Python programming language using the Django web framework. In order tomore » promote collaboration and validation from other centres the code was made open source and is freely available to the public via an online source code repository. The code was written to provide a common user interface for data entry, formalize the review and approval process, and offer automated data trending and process control analysis of test results. Results: As of February 2014, our installation of QAtrack+ has 180 tests defined in its database and has collected ∼22 000 test results, all of which have been reviewed and approved by a physicist via QATrack+'s review tools. These results include records for quality control of Elekta accelerators, CT simulators, our brachytherapy programme, TomoTherapy and Cyberknife units. Currently at least 5 other centres are known to be running QAtrack+ clinically, forming the start of an international user community. Conclusion: QAtrack+ has proven to be an effective tool for collecting radiation therapy QC data, allowing for rapid review and trending of data for a wide variety of treatment units. As free and open source software, all source code, documentation and a bug tracker are available to the public at https://bitbucket.org/tohccmedphys/qatrackplus/.« less

Mediastinal irradiation in a patient affected by lung carcinoma after heart transplantation: Helical tomotherapy versus three dimensional conformal radiotherapy.

PubMed

Giugliano, Francesca M; Iorio, Vincenzo; Cammarota, Fabrizio; Toledo, Diego; Senese, Rossana; Francomacaro, Ferdinando; Muto, Matteo; Muto, Paolo

2016-04-26

Patients who have undergone solid organ transplants are known to have an increased risk of neoplasia compared with the general population. We report our experience using mediastinal irradiation with helical tomotherapy versus three-dimensional conformal radiation therapy to treat a patient with lung carcinoma 15 years after heart transplantation. Our dosimetric evaluation showed no particular difference between the techniques, with the exception of some organs. Mediastinal irradiation after heart transplantation is feasible and should be considered after evaluation of the risk. Conformal radiotherapy or intensity-modulated radiotherapy appears to be the appropriate treatment in heart-transplanted oncologic patients.

A case study for online plan adaptation using helical tomotherapy

PubMed Central

Neilson, Christopher E.; Yartsev, Slav

2012-01-01

Helical tomotherapy's ability to provide daily megavoltage (MV) computed tomography (CT) images for patient set-up verification allows for the creation of adapted plans. As plans become more complex by introducing sharper dose gradients in an effort to spare healthy tissue, inter-fraction changes of organ position with respect to plan become a limiting factor in the correct dose delivery to the target. Tomotherapy's planned adaptive option provides the possibility to evaluate the dose distribution for each fraction and subsequently adapt the original plan to the current anatomy. In this study, 30 adapted plans were created using new contours based on the daily MVCT studies of a bladder cancer patient with considerable anatomical variations. Dose to the rectum and two planning target volumes (PTVs) were compared between the original plan, the dose that was actually delivered to the patient, and the theoretical dose from the 30 adapted plans. The adaptation simulation displayed a lower dose to 35% and 50% of the rectum compared to no adaptation at all, while maintaining an equivalent dose to the PTVs. Although online adaptation is currently too time-consuming, it has the potential to improve the effectiveness of radiotherapy. PMID:22557799

The validation of tomotherapy dose calculations in low-density lung media

NASA Astrophysics Data System (ADS)

Chaudhari, Summer R.; Pechenaya, Olga L.; Goddu, S. Murty; Mutic, Sasa; Rangaraj, Dharanipathy; Bradley, Jeffrey D.; Low, Daniel

2009-04-01

The dose-calculation accuracy of the tomotherapy Hi-Art II® (Tomotherapy, Inc., Madison, WI) treatment planning system (TPS) in the presence of low-density lung media was investigated. In this evaluation, a custom-designed heterogeneous phantom mimicking the mediastinum geometry was used. Gammex LN300 and balsa wood were selected as two lung-equivalent materials with different densities. Film analysis and ionization chamber measurements were performed. Treatment plans for esophageal cancers were used in the evaluation. The agreement between the dose calculated by the TPS and the dose measured via ionization chambers was, in most cases, within 0.8%. Gamma analysis using 3% and 3 mm criteria for radiochromic film dosimetry showed that 98% and 95% of the measured dose distribution had passing gamma values <=1 for LN300 and balsa wood, respectively. For a homogeneous water-equivalent phantom, 95% of the points passed the gamma test. It was found that for the interface between the low-density medium and water-equivalent medium, the TPS calculated the dose distribution within acceptable limits. The phantom developed for this work enabled detailed quality-assurance testing under realistic conditions with heterogeneous media.

The validation of tomotherapy dose calculations in low-density lung media.

PubMed

Chaudhari, Summer R; Pechenaya, Olga L; Goddu, S Murty; Mutic, Sasa; Rangaraj, Dharanipathy; Bradley, Jeffrey D; Low, Daniel

2009-04-21

The dose-calculation accuracy of the tomotherapy Hi-Art II(R) (Tomotherapy, Inc., Madison, WI) treatment planning system (TPS) in the presence of low-density lung media was investigated. In this evaluation, a custom-designed heterogeneous phantom mimicking the mediastinum geometry was used. Gammex LN300 and balsa wood were selected as two lung-equivalent materials with different densities. Film analysis and ionization chamber measurements were performed. Treatment plans for esophageal cancers were used in the evaluation. The agreement between the dose calculated by the TPS and the dose measured via ionization chambers was, in most cases, within 0.8%. Gamma analysis using 3% and 3 mm criteria for radiochromic film dosimetry showed that 98% and 95% of the measured dose distribution had passing gamma values < or =1 for LN300 and balsa wood, respectively. For a homogeneous water-equivalent phantom, 95% of the points passed the gamma test. It was found that for the interface between the low-density medium and water-equivalent medium, the TPS calculated the dose distribution within acceptable limits. The phantom developed for this work enabled detailed quality-assurance testing under realistic conditions with heterogeneous media.

SU-F-T-435: Helical Tomotherapy for Craniospinal Irradiation: What We Have Learned from a Multi-Institutional Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Du, D; Kaprealian, T; Low, D

Purpose: To report cranio-spinal irradiation (CSI) planning experience, compare dosimetric quality and delivery efficiency with Tomotherapy from different institutions, and to investigate effect of planning parameters on plan quality and treatment time. Methods: Clinical helical tomotherapy IMRT plans for thirty-nine CSI cases from three academic institutions were retrospectively evaluated. The planning parameters: field width (FW), pitch, modulation factor (MF), and achieved dosimetric endpoints were cross-compared. A fraction-dose-delivery-timing index (FDTI), defined as treatment time per fraction dose per PTV length, was utilized to evaluate plan delivery efficiency. A lower FDTI indicates higher delivery efficiency. We studied the correlation between planning quality,more » treatment time and planning parameters by grouping the plans under specific planning parameters. Additionally, we created new plans using 5cm jaw for a subset of plans that used 2.5cm jaw to exam if treatment efficiency can be improved without sacrificing plan quality. Results: There were significant dosimetric differences for organ at risks (OARs) among different institutions (A,B,C). Using the lowest average MF (1.9±0.4) and 5cm field width, C had the highest lung, heart, kidney, liver mean doses and maximum doses for lens. Using the same field width of 5cm, but higher MF (2.6±0.6), B had lower doses to the OARs in the thorax and abdomen area. Most of A’s plans were planned with 2.5cm jaw, the plans yielded better PTV coverage, higher OAR doses and slightly shorter FDTI compared to institution B. The replanned 5cm jaw plans achieved comparable PTV coverage and OARs sparing, while saving up to 44.7% treatment time. Conclusion: Plan quality and delivery efficiency could vary significantly in CSI planning on Tomotheapy due to choice of different planning parameters. CSI plans using a 5cm jaw, with proper selection of pitch and MF, can achieve comparable/ better plan quality with shorter delivery time compared to 2.5cm jaw plans.« less

SU-D-BRF-03: Improvement of TomoTherapy Megavoltage Topogram Image Quality for Automatic Registration During Patient Localization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scholey, J; White, B; Qi, S

2014-06-01

Purpose: To improve the quality of mega-voltage orthogonal scout images (MV topograms) for a fast and low-dose alternative technique for patient localization on the TomoTherapy HiART system. Methods: Digitally reconstructed radiographs (DRR) of anthropomorphic head and pelvis phantoms were synthesized from kVCT under TomoTherapy geometry (kV-DRR). Lateral (LAT) and anterior-posterior (AP) aligned topograms were acquired with couch speeds of 1cm/s, 2cm/s, and 3cm/s. The phantoms were rigidly translated in all spatial directions with known offsets in increments of 5mm, 10mm, and 15mm to simulate daily positioning errors. The contrast of the MV topograms was automatically adjusted based on the imagemore » intensity characteristics. A low-pass fast Fourier transform filter removed high-frequency noise and a Weiner filter reduced stochastic noise caused by scattered radiation to the detector array. An intensity-based image registration algorithm was used to register the MV topograms to a corresponding kV-DRR by minimizing the mean square error between corresponding pixel intensities. The registration accuracy was assessed by comparing the normalized cross correlation coefficients (NCC) between the registered topograms and the kV-DRR. The applied phantom offsets were determined by registering the MV topograms with the kV-DRR and recovering the spatial translation of the MV topograms. Results: The automatic registration technique provided millimeter accuracy and was robust for the deformed MV topograms for three tested couch speeds. The lowest average NCC for all AP and LAT MV topograms was 0.96 for the head phantom and 0.93 for the pelvis phantom. The offsets were recovered to within 1.6mm and 6.5mm for the processed and the original MV topograms respectively. Conclusion: Automatic registration of the processed MV topograms to a corresponding kV-DRR recovered simulated daily positioning errors that were accurate to the order of a millimeter. These results suggest the clinical use of MV topograms as a promising alternative to MVCT patient alignment.« less

WE-DE-BRA-09: Fast Megavoltage CT Imaging with Rapid Scan Time and Low Imaging Dose in Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Magome, T; University of Tokyo Hospital, Tokyo; University of Minnesota, Minneapolis, MN

Purpose: Megavoltage computed tomography (MVCT) imaging has been widely used for daily patient setup with helical tomotherapy (HT). One drawback of MVCT is its very long imaging time, owing to slow couch speed. The purpose of this study was to develop an MVCT imaging method allowing faster couch speeds, and to assess its accuracy for image guidance for HT. Methods: Three cadavers (mimicking closest physiological and physical system of patients) were scanned four times with couch speeds of 1, 2, 3, and 4 mm/s. The resulting MVCT images were reconstructed using an iterative reconstruction (IR) algorithm. The MVCT images weremore » registered with kilovoltage CT images, and the registration errors were compared with the errors with conventional filtered back projection (FBP) algorithm. Moreover, the fast MVCT imaging was tested in three cases of total marrow irradiation as a clinical trial. Results: Three-dimensional registration errors of the MVCT images reconstructed with the IR algorithm were significantly smaller (p < 0.05) than the errors of images reconstructed with the FBP algorithm at fast couch speeds (3, 4 mm/s). The scan time and imaging dose at a speed of 4 mm/s were reduced to 30% of those from a conventional coarse mode scan. For the patient imaging, a limited number of conventional MVCT (1.2 mm/s) and fast MVCT (3 mm/s) reveals acceptable reduced imaging time and dose able to use for anatomical registration. Conclusion: Fast MVCT with IR algorithm maybe clinically feasible alternative for rapid 3D patient localization. This technique may also be useful for calculating daily dose distributions or organ motion analyses in HT treatment over a wide area.« less

Intensity-Modulated Radiotherapy Might Increase Pneumonitis Risk Relative to Three-Dimensional Conformal Radiotherapy in Patients Receiving Combined Chemotherapy and Radiotherapy: A Modeling Study of Dose Dumping

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vogelius, Ivan S.; Department of Human Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI; Department of Radiation Oncology, Rigshospitalet

2011-07-01

Purpose: To model the possible interaction between cytotoxic chemotherapy and the radiation dose distribution with respect to the risk of radiation pneumonitis. Methods and Materials: A total of 18 non-small-cell lung cancer patients previously treated with helical tomotherapy at the University of Wisconsin were selected for the present modeling study. Three treatment plans were considered: the delivered tomotherapy plans; a three-dimensional conformal radiotherapy (3D-CRT) plan; and a fixed-field intensity-modulated radiotherapy (IMRT) plan. The IMRT and 3D-CRT plans were generated specifically for the present study. The plans were optimized without adjusting for the chemotherapy effect. The effect of chemotherapy was modeledmore » as an independent cell killing process by considering a uniform chemotherapy equivalent radiation dose added to all voxels of the organ at risk. The risk of radiation pneumonitis was estimated for all plans using the Lyman and the critical volume models. Results: For radiotherapy alone, the critical volume model predicts that the two IMRT plans are associated with a lower risk of radiation pneumonitis than the 3D-CRT plan. However, when the chemotherapy equivalent radiation dose exceeds a certain threshold, the radiation pneumonitis risk after IMRT is greater than after 3D-CRT. This threshold dose is in the range estimated from clinical chemoradiotherapy data sets. Conclusions: Cytotoxic chemotherapy might affect the relative merit of competing radiotherapy plans. More work is needed to improve our understanding of the interaction between chemotherapy and the radiation dose distribution in clinical settings.« less

Aichi Cancer Center Initial Experience of Intensity Modulated Radiation Therapy for Nasopharyngeal Cancer Using Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kodaira, Takeshi; Tomita, Natsuo; Tachibana, Hiroyuki

Purpose: To assess the feasibility of helical tomotherapy (HT) for patients with nasopharyngeal carcinoma. Methods and Materials: From June 2006 to June 2007, 20 patients with nasopharyngeal carcinoma were treated with HT with (n = 18) or without (n = 2) systemic chemotherapy. The primary tumor and involved lymph node (PTV1) were prescribed 70 Gy and the prophylactic region 54 Gy at D95, respectively. The majority of patients received 2 Gy per fraction for PTV1 in 35 fractions. Parotid function was evaluated using quantitative scintigraphy at pretreatment, and posttreatment at 3 months and 1 year later. Results: The median patientmore » age was 53 years, ranging from 15 to 83. Our cohort included 5, 8, 4, 2, and 1 patients with disease Stages IIB, III, IVA, IVB, and IVC, respectively. Histopathological record revealed two for World Health Organization Type I and 18 for Type 2 or 3. The median duration time for treatment preparation was 9.5 days, and all plans were thought to be acceptable regarding dose constraints of both the planning target volume and organ at risk. All patients completed their treatment procedure of intensity-modulated radiation therapy (IMRT). All patients achieved clinical remission after IMRT. The majority of patients had Grade 3 or higher toxicity of skin, mucosa, and neutropenia. At the median follow-up of 10.9 months, two patients recurred, and one patient died from cardiac disease. Parotid gland function at 1 year after completion of IMRT was significantly improved compared with that at 3 months. Conclusion: HT was clinically effective in terms of IMRT planning and utility for patients with nasopharyngeal cancer.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leney, M; Nalichowski, A; Patel, S

Purpose: To determine the effects of patient separation on absolute dose and dose distribution in patients undergoing pelvic radiotherapy on TomoTherapy. Methods: An Alderson RANDO phantom with 4cm of bolus was imaged on a CT simulator and the resulting scans were contoured as a whole pelvic case. Using TomoTherapy Planning Station, the plan was designed to give 45 Gy to 95% of the treatment volume in 25 fractions. TomoTherapy MVCT scans were performed on the RANDO phantom with 2cm and 4cm of bolus removed to simulate visible changes in a patient’s anatomy. The MVCT images were rigidly registered with planningmore » CT images on TomoTherapy Planned Adaptive. The original fluence was recalculated on the MVCT images and changes in dose distribution due to patient separation were quantified by the changes in DVHs for the target volume and the organs at risk. Results: Patient separation difference equivalent to 2cm and 4cm in anterior-posterior direction resulted in an increase of the PTV D50 and maximum PTV dose of 5.6%, 6.2% for 2cm and 7.7%, 10.4% for 4cm, respectively. For the 2cm change, D50 and maximum doses to organs at risk increased by 6.5%, 7.1% in the bladder, 4.9%, 4.8% in the rectum, and 5.3%, 6.6% in the bowel. For the 4cm change, D50 and maximum doses increased by 10.7%, 12.2% in the bladder, 5.9%, 6.1% in the rectum, and 7.7%, 10.1% in the bowel. Conclusion: This research indicates that, without any changes to the structures, patient separation in the anterior-posterior direction can affect the dose distribution for the PTV and organs at risk. These results can assist physicians in determining if obtaining a new CT simulation set and replanning is necessary for pelvic patients on TomoTherapy.« less

Prospective Phase I-II Trial of Helical Tomotherapy With or Without Chemotherapy for Postoperative Cervical Cancer Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schwarz, Julie K., E-mail: jschwarz@radonc.wustl.edu; Department of Cell Biology and Physiology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO; Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO

2011-12-01

Purpose: To investigate, in a prospective trial, the acute and chronic toxicity of patients with cervical cancer treated with surgery and postoperative intensity-modulated radiotherapy (RT) delivered using helical tomotherapy, with or without the administration of concurrent chemotherapy. Patients and Methods: A total of 24 evaluable patients entered the study between March 2006 and August 2009. The indications for postoperative RT were tumor size, lymphovascular space invasion, and the depth of cervical stromal invasion in 15 patients; 9 patients underwent postoperative RT because of surgically positive lymph nodes. All patients underwent pelvic RT delivered with helical tomotherapy and intracavitary high-dose-rate brachytherapy.more » Treatment consisted of concurrent weekly platinum in 17, sequential carboplatin/Taxol in 1, and RT alone in 6. The patients were monitored for acute and chronic toxicity using the Common Toxicity Criteria, version 3.0. Results: The median follow-up was 24 months (range, 4-49). At the last follow-up visit, 23 patients were alive and disease free. Of the 24 patients, 12 (50%) experienced acute Grade 3 gastrointestinal toxicity (anorexia in 5, diarrhea in 4, and nausea in 3). One patient developed acute Grade 4 genitourinary toxicity (vesicovaginal fistula). For patients treated with concurrent chemotherapy, the incidence of acute Grade 3 and 4 hematologic toxicity was 71% and 24%, respectively. For patients treated without concurrent chemotherapy, the incidence of acute Grade 3 and 4 hematologic toxicity was 29% and 14%, respectively. Two long-term toxicities occurred (vesicovaginal fistula at 25 months and small bowel obstruction at 30 months). The overall and progression-free survival rate at 3 years for all patients was 100% and 89%, respectively. Conclusion: The results of our study have shown that postoperative external RT for cervical cancer delivered with helical tomotherapy and high-dose-rate brachytherapy and with or without chemotherapy is feasible, with acceptable acute and chronic toxicity.« less

Automatic detection of patient identification and positioning errors in radiation therapy treatment using 3-dimensional setup images.

PubMed

Jani, Shyam S; Low, Daniel A; Lamb, James M

2015-01-01

To develop an automated system that detects patient identification and positioning errors between 3-dimensional computed tomography (CT) and kilovoltage CT planning images. Planning kilovoltage CT images were collected for head and neck (H&N), pelvis, and spine treatments with corresponding 3-dimensional cone beam CT and megavoltage CT setup images from TrueBeam and TomoTherapy units, respectively. Patient identification errors were simulated by registering setup and planning images from different patients. For positioning errors, setup and planning images were misaligned by 1 to 5 cm in the 6 anatomical directions for H&N and pelvis patients. Spinal misalignments were simulated by misaligning to adjacent vertebral bodies. Image pairs were assessed using commonly used image similarity metrics as well as custom-designed metrics. Linear discriminant analysis classification models were trained and tested on the imaging datasets, and misclassification error (MCE), sensitivity, and specificity parameters were estimated using 10-fold cross-validation. For patient identification, our workflow produced MCE estimates of 0.66%, 1.67%, and 0% for H&N, pelvis, and spine TomoTherapy images, respectively. Sensitivity and specificity ranged from 97.5% to 100%. MCEs of 3.5%, 2.3%, and 2.1% were obtained for TrueBeam images of the above sites, respectively, with sensitivity and specificity estimates between 95.4% and 97.7%. MCEs for 1-cm H&N/pelvis misalignments were 1.3%/5.1% and 9.1%/8.6% for TomoTherapy and TrueBeam images, respectively. Two-centimeter MCE estimates were 0.4%/1.6% and 3.1/3.2%, respectively. MCEs for vertebral body misalignments were 4.8% and 3.6% for TomoTherapy and TrueBeam images, respectively. Patient identification and gross misalignment errors can be robustly and automatically detected using 3-dimensional setup images of different energies across 3 commonly treated anatomical sites. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Proof of Principle of Ocular sparing in dogs with sinonasal tumors treated with intensity-modulated radiation therapy

PubMed Central

Lawrence, Jessica A.; Forrest, Lisa J.; Turek, Michelle M.; Miller, Paul E.; Mackie, T. Rockwell; Jaradat, Hazim A.; Vail, David M.; Dubielzig, Richard R.; Chappell, Richard; Mehta, Minesh P.

2010-01-01

Intensity modulated radiation therapy (IMRT) allows optimization of radiation dose delivery to complex tumor volumes with rapid dose drop-off to surrounding normal tissues. A prospective study was performed to evaluate the concept of conformal avoidance using IMRT in canine sinonasal cancer. The potential of IMRT to improve clinical outcome with respect to acute and late ocular toxicity was evaluated. Thirty-one dogs with sinonasal cancer were treated definitively with IMRT using helical tomotherapy and/or dynamic multileaf collimator (DMLC) delivery. Ocular toxicity was evaluated prospectively and compared to a comparable group of historical controls treated with conventional two-dimensional radiotherapy (2D-RT) techniques. Treatment plans were devised for each dog using helical tomotherapy and DMLC that achieved the target dose to the planning treatment volume and limited critical normal tissues to the prescribed dose-volume constraints. Overall acute and late toxicities were limited and minor, detectable by an experienced observer. This was in contrast to the profound ocular morbidity observed in the historical control group treated with 2D-RT. Overall median survival for IMRT treated and 2D treated dogs was 420 days and 411 days, respectively. Compared with conventional techniques, IMRT reduced dose delivered to eyes and resulted in bilateral ocular sparing in the dogs reported herein. These data provide proof-of-principle that conformal avoidance radiotherapy can be delivered through high conformity IMRT, resulting in decreased normal tissue toxicity as compared to historical controls treated with 2D-RT. PMID:20973393

Dosimetric comparison of helical tomotherapy, intensity-modulated radiation therapy, volumetric-modulated arc therapy, and 3-dimensional conformal therapy for the treatment of T1N0 glottic cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ekici, Kemal, E-mail: drkemal06@hotmail.com; Pepele, Eda K.; Yaprak, Bahaddin

2016-01-01

Various radiotherapy planning methods for T1N0 laryngeal cancer have been proposed to decrease normal tissue toxicity. We compare helical tomotherapy (HT), linac-based intensity-modulated radiation therapy (IMRT), volumetric-modulated arc therapy (VMAT), and 3-D conformal radiotherapy (3D-CRT) techniques for T1N0 laryngeal cancer. Overall, 10 patients with T1N0 laryngeal cancer were selected and evaluated. Furthermore, 10 radiotherapy treatment plans have been created for all 10 patients, including HT, IMRT, VMAT, and 3D-CRT. IMRT, VMAT, and HT plans vs 3D-CRT plans consistently provided superior planning target volume (PTV) coverage. Similar target coverage was observed between the 3 IMRT modalities. Compared with 3D-CRT, IMRT, HT,more » and VMAT significantly reduced the mean dose to the carotid arteries. VMAT resulted in the lowest mean dose to the submandibular and thyroid glands. Compared with 3D-CRT, IMRT, HT, and VMAT significantly increased the maximum dose to the spinal cord It was observed that the 3 IMRT modalities studied showed superior target coverage with less variation between each plan in comparison with 3D-CRT. The 3D-CRT plans performed better at the D{sub max} of the spinal cord. Clinical investigation is warranted to determine if these treatment approaches would translate into a reduction in radiation therapy–induced toxicities.« less

Assessment of a three‐dimensional (3D) water scanning system for beam commissioning and measurements on a helical tomotherapy unit

PubMed Central

Ashenafi, Michael S.; McDonald, Daniel G.; Vanek, Kenneth N.

2015-01-01

Beam scanning data collected on the tomotherapy linear accelerator using the TomoScanner water scanning system is primarily used to verify the golden beam profiles included in all Helical TomoTherapy treatment planning systems (TOMO TPSs). The user is not allowed to modify the beam profiles/parameters for beam modeling within the TOMO TPSs. The authors report the first feasibility study using the Blue Phantom Helix (BPH) as an alternative to the TomoScanner (TS) system. This work establishes a benchmark dataset using BPH for target commissioning and quality assurance (QA), and quantifies systematic uncertainties between TS and BPH. Reproducibility of scanning with BPH was tested by three experienced physicists taking five sets of measurements over a six‐month period. BPH provides several enhancements over TS, including a 3D scanning arm, which is able to acquire necessary beam‐data with one tank setup, a universal chamber mount, and the OmniPro software, which allows online data collection and analysis. Discrepancies between BPH and TS were estimated by acquiring datasets with each tank. In addition, data measured with BPH and TS was compared to the golden TOMO TPS beam data. The total systematic uncertainty, defined as the combination of scanning system and beam modeling uncertainties, was determined through numerical analysis and tabulated. OmniPro was used for all analysis to eliminate uncertainty due to different data processing algorithms. The setup reproducibility of BPH remained within 0.5 mm/0.5%. Comparing BPH, TS, and Golden TPS for PDDs beyond maximum depth, the total systematic uncertainties were within 1.4 mm/2.1%. Between BPH and TPS golden data, maximum differences in the field width and penumbra of in‐plane profiles were within 0.8 and 1.1 mm, respectively. Furthermore, in cross‐plane profiles, the field width differences increased at depth greater than 10 cm up to 2.5 mm, and maximum penumbra uncertainties were 5.6 mm and 4.6 mm from TS scanning system and TPS modeling, respectively. Use of BPH reduced measurement time by 1–2 hrs per session. The BPH has been assessed as an efficient, reproducible, and accurate scanning system capable of providing a reliable benchmark beam data. With this data, a physicist can utilize the BPH in a clinical setting with an understanding of the scan discrepancy that may be encountered while validating the TPS or during routine machine QA. Without the flexibility of modifying the TPS and without a golden beam dataset from the vendor or a TPS model generated from data collected with the BPH, this represents the best solution for current clinical use of the BPH. PACS number: 87.56.Fc

SU-E-T-73: A Robust Proton Beam Therapy Technique for High-Risk Prostate Cancer Whole Pelvis Irradiation: Bilateral Opposed Single Field Uniform Dose (SFUD) Plan with Lateral Penumbra Gradient Matching

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ding, X; Wu, H; Rosen, L

2015-06-15

Purpose: To develop a clinical feasible and robust proton therapy technique to spare bowel, bladder and rectum for high-risk prostate cancer patients Methods: The study includes 3 high-risk prostate cancer cases treated with bilateral opposed SFUD with lateral penumbra gradient matching technique prescribed to 5400cGyE in 30 fx in our institution. To treat whole pelvic lymph node chain, the complicated ‘H’ shape, using SFUD technique, we divided the target into two sub-targets (LLAT beam treating ‘90 degree T-shape’ and RLAT beam treating ‘: shape’) in Plan A and use lateral penumbra gradient matching at patient’s left side. Vice verse inmore » Plan B. Each plan deliver half of the prescription dose. Beam-specific PTVs were created to take range uncertainty and setup error into account. For daily treatment, patient received four fields from both plan A and B per day. Robustness evaluation were performed in the worst case scenario with 3.5% range uncertainty and 1, 2, 3mm overlap or gap between LLAT and RLAT field matching in Raystation 4.0. All of cases also have a Tomotherapy backup plan approved by physician as a dosimetric comparison. Results: The total treatment time take 15–20mins including IGRT and four fields delivery on ProteusONE, a compact size PBS proton system, compared to 25–30min in traditional Tomotherapy. Robustness analysis shows that this plan technique is insensitive to the range uncertainties. With the lateral gradient matching, 1, 2, 3mm overlap renders only 2.5%, 5.5% and 8% hot or cool spot in the junction areas. Dosimetric comparisons with Tomotherapy show a significant dose reduction in bladder D50%(14.7±9.3Gy), D35%(7.3±5.8Gy); small bowel and rectum average dose(19.6±7.5Gy and 14.5±6.3Gy respectively). Conclusion: The bilateral opposed(SFUD) plan with lateral penumbra gradient matching has been approved to be a safe, robust and efficient treatment option for whole pelvis high-risk prostate cancer patient which significantly spares the OARs.« less

SU-E-T-261: Development of An Automated System to Detect Patient Identification and Positioning Errors Prior to Radiotherapy Treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jani, S; Low, D; Lamb, J

2015-06-15

Purpose: To develop a system that can automatically detect patient identification and positioning errors using 3D computed tomography (CT) setup images and kilovoltage CT (kVCT) planning images. Methods: Planning kVCT images were collected for head-and-neck (H&N), pelvis, and spine treatments with corresponding 3D cone-beam CT (CBCT) and megavoltage CT (MVCT) setup images from TrueBeam and TomoTherapy units, respectively. Patient identification errors were simulated by registering setup and planning images from different patients. Positioning errors were simulated by misaligning the setup image by 1cm to 5cm in the six anatomical directions for H&N and pelvis patients. Misalignments for spine treatments weremore » simulated by registering the setup image to adjacent vertebral bodies on the planning kVCT. A body contour of the setup image was used as an initial mask for image comparison. Images were pre-processed by image filtering and air voxel thresholding, and image pairs were assessed using commonly-used image similarity metrics as well as custom -designed metrics. A linear discriminant analysis classifier was trained and tested on the datasets, and misclassification error (MCE), sensitivity, and specificity estimates were generated using 10-fold cross validation. Results: Our workflow produced MCE estimates of 0.7%, 1.7%, and 0% for H&N, pelvis, and spine TomoTherapy images, respectively. Sensitivities and specificities ranged from 98.0% to 100%. MCEs of 3.5%, 2.3%, and 2.1% were obtained for TrueBeam images of the above sites, respectively, with sensitivity and specificity estimates between 96.2% and 98.4%. MCEs for 1cm H&N/pelvis misalignments were 1.3/5.1% and 9.1/8.6% for TomoTherapy and TrueBeam images, respectively. 2cm MCE estimates were 0.4%/1.6% and 3.1/3.2%, respectively. Vertebral misalignment MCEs were 4.8% and 4.9% for TomoTherapy and TrueBeam images, respectively. Conclusion: Patient identification and gross misalignment errors can be robustly and automatically detected using 3D setup images of two imaging modalities across three commonly-treated anatomical sites.« less

Helical tomotherapy to LINAC plan conversion utilizing RayStation Fallback planning.

PubMed

Zhang, Xin; Penagaricano, Jose; Narayanasamy, Ganesh; Corry, Peter; Liu, TianXiao; Sanjay, Maraboyina; Paudel, Nava; Morrill, Steven

2017-01-01

RaySearch RayStation Fallback (FB) planning module can generate an equivalent backup radiotherapy treatment plan facilitating treatment on other linear accelerators. FB plans were generated from the RayStation FB module by simulating the original plan target and organ at risk (OAR) dose distribution and delivered in various backup linear accelerators. In this study, helical tomotherapy (HT) backup plans used in Varian TrueBeam linear accelerator were generated with the RayStation FB module. About 30 patients, 10 with lung cancer, 10 with head and neck (HN) cancer, and 10 with prostate cancer, who were treated with HT, were included in this study. Intensity-modulated radiotherapy Fallback plans (FB-IMRT) were generated for all patients, and three-dimensional conformal radiotherapy Fallback plans (FB-3D) were only generated for lung cancer patients. Dosimetric comparison study evaluated FB plans based on dose coverage to 95% of the PTV volume (R 95 ), PTV mean dose (D mean ), Paddick's conformity index (CI), and dose homogeneity index (HI). The evaluation results showed that all IMRT plans were statistically comparable between HT and FB-IMRT plans except that PTV HI was worse in prostate, and PTV R 95 and HI were worse in HN multitarget plans for FB-IMRT plans. For 3D lung cancer plans, only the PTV R 95 was statistically comparable between HT and FB-3D plans, PTV D mean was higher, and CI and HI were worse compared to HT plans. The FB plans using a TrueBeam linear accelerator generally offer better OAR sparing compared to HT plans for all the patients. In this study, all cases of FB-IMRT plans and 9/10 cases of FB-3D plans were clinically acceptable without further modification and optimization once the FB plans were generated. However, the statistical differences between HT and FB-IMRT/3D plans might not be of any clinically significant. One FB-3D plan failed to simulate the original plan without further optimization. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Bolus-dependent dosimetric effect of positioning errors for tangential scalp radiotherapy with helical tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lobb, Eric, E-mail: eclobb2@gmail.com

2014-04-01

The dosimetric effect of errors in patient position is studied on-phantom as a function of simulated bolus thickness to assess the need for bolus utilization in scalp radiotherapy with tomotherapy. A treatment plan is generated on a cylindrical phantom, mimicking a radiotherapy technique for the scalp utilizing primarily tangential beamlets. A planning target volume with embedded scalplike clinical target volumes (CTVs) is planned to a uniform dose of 200 cGy. Translational errors in phantom position are introduced in 1-mm increments and dose is recomputed from the original sinogram. For each error the maximum dose, minimum dose, clinical target dose homogeneitymore » index (HI), and dose-volume histogram (DVH) are presented for simulated bolus thicknesses from 0 to 10 mm. Baseline HI values for all bolus thicknesses were in the 5.5 to 7.0 range, increasing to a maximum of 18.0 to 30.5 for the largest positioning errors when 0 to 2 mm of bolus is used. Utilizing 5 mm of bolus resulted in a maximum HI value of 9.5 for the largest positioning errors. Using 0 to 2 mm of bolus resulted in minimum and maximum dose values of 85% to 94% and 118% to 125% of the prescription dose, respectively. When using 5 mm of bolus these values were 98.5% and 109.5%. DVHs showed minimal changes in CTV dose coverage when using 5 mm of bolus, even for the largest positioning errors. CTV dose homogeneity becomes increasingly sensitive to errors in patient position as bolus thickness decreases when treating the scalp with primarily tangential beamlets. Performing a radial expansion of the scalp CTV into 5 mm of bolus material minimizes dosimetric sensitivity to errors in patient position as large as 5 mm and is therefore recommended.« less

Investigation of the feasibility of a simple method for verifying the motion of a binary multileaf collimator synchronized with the rotation of the gantry for helical tomotherapy

PubMed Central

Uematsu, Masahiro; Ito, Makiko; Hama, Yukihiro; Inomata, Takayuki; Fujii, Masahiro; Nishio, Teiji; Nakamura, Naoki; Nakagawa, Keiichi

2012-01-01

In this paper, we suggest a new method for verifying the motion of a binary multileaf collimator (MLC) in helical tomotherapy. For this we used a combination of a cylindrical scintillator and a general‐purpose camcorder. The camcorder records the light from the scintillator following photon irradiation, which we use to track the motion of the binary MLC. The purpose of this study is to demonstrate the feasibility of this method as a binary MLC quality assurance (QA) tool. First, the verification was performed using a simple binary MLC pattern with a constant leaf open time; secondly, verification using the binary MLC pattern used in a clinical setting was also performed. Sinograms of simple binary MLC patterns, in which leaves that were open were detected as “open” from the measured light, define the sensitivity which, in this case, was 1.000. On the other hand, the specificity, which gives the fraction of closed leaves detected as “closed”, was 0.919. The leaf open error identified by our method was −1.3±7.5%. The 68.6% of observed leaves were performed within ± 3% relative error. The leaf open error was expressed by the relative errors calculated on the sinogram. In the clinical binary MLC pattern, the sensitivity and specificity were 0.994 and 0.997, respectively. The measurement could be performed with −3.4±8.0% leaf open error. The 77.5% of observed leaves were performed within ± 3% relative error. With this method, we can easily verify the motion of the binary MLC, and the measurement unit developed was found to be an effective QA tool. PACS numbers: 87.56.Fc, 87.56.nk PMID:22231222

Clinical implementation of an exit detector-based dose reconstruction tool for helical tomotherapy delivery quality assurance.

PubMed

Deshpande, Shrikant; Xing, Aitang; Metcalfe, Peter; Holloway, Lois; Vial, Philip; Geurts, Mark

2017-10-01

The aim of this study was to validate the accuracy of an exit detector-based dose reconstruction tool for helical tomotherapy (HT) delivery quality assurance (DQA). Exit detector-based DQA tool was developed for patient-specific HT treatment verification. The tool performs a dose reconstruction on the planning image using the sinogram measured by the HT exit detector with no objects in the beam (i.e., static couch), and compares the reconstructed dose to the planned dose. Vendor supplied (three "TomoPhant") plans with a cylindrical solid water ("cheese") phantom were used for validation. Each "TomoPhant" plan was modified with intentional multileaf collimator leaf open time (MLC LOT) errors to assess the sensitivity and robustness of this tool. Four scenarios were tested; leaf 32 was "stuck open," leaf 42 was "stuck open," random leaf LOT was closed first by mean values of 2% and then 4%. A static couch DQA procedure was then run five times (once with the unmodified sinogram and four times with modified sinograms) for each of the three "TomoPhant" treatment plans. First, the original optimized delivery plan was compared with the original machine agnostic delivery plan, then the original optimized plans with a known modification applied (intentional MLC LOT error) were compared to the corresponding error plan exit detector measurements. An absolute dose comparison between calculated and ion chamber (A1SL, Standard Imaging, Inc., WI, USA) measured dose was performed for the unmodified "TomoPhant" plans. A 3D gamma evaluation (2%/2 mm global) was performed by comparing the planned dose ("original planned dose" for unmodified plans and "adjusted planned dose" for each intentional error) to exit detector-reconstructed dose for all three "Tomophant" plans. Finally, DQA for 119 clinical (treatment length <25 cm) and three cranio-spinal irradiation (CSI) plans were measured with both the ArcCHECK phantom (Sun Nuclear Corp., Melbourne, FL, USA) and the exit detector DQA tool to assess the time required for DQA and similarity between two methods. The measured ion chamber dose agreed to within 1.5% of the reconstructed dose computed by the exit detector DQA tool on a cheese phantom for all unmodified "Tomophant" plans. Excellent agreement in gamma pass rate (>95%) was observed between the planned and reconstructed dose for all "Tomophant" plans considered using the tool. The gamma pass rate from 119 clinical plan DQA measurements was 94.9% ± 1.5% and 91.9% ± 4.37% for the exit detector DQA tool and ArcCHECK phantom measurements (P = 0.81), respectively. For the clinical plans (treatment length <25 cm), the average time required to perform DQA was 24.7 ± 3.5 and 39.5 ± 4.5 min using the exit detector QA tool and ArcCHECK phantom, respectively, whereas the average time required for the 3 CSI treatments was 35 ± 3.5 and 90 ± 5.2 min, respectively. The exit detector tool has been demonstrated to be faster for performing the DQA with equivalent sensitivity for detecting MLC LOT errors relative to a conventional phantom-based QA method. In addition, comprehensive MLC performance evaluation and features of reconstructed dose provide additional insight into understanding DQA failures and the clinical relevance of DQA results. © 2017 American Association of Physicists in Medicine.

Fan-shaped complete block on helical tomotherapy for esophageal cancer: a phantom study.

PubMed

Chang, Chiu-Han; Mok, Greta S P; Shueng, Pei-Wei; Yeh, Hsin-Pei; Shiau, An-Cheng; Tien, Hui-Ju; Lin, Chi-Ta; Wu, Tung-Hsin

2015-01-01

Radiation pneumonitis (RP) is a common complication for radiotherapy of esophageal cancer and is associated with the low dose irradiated lung volume. This study aims to reduce the mean lung dose (MLD) and the relative lung volume at 20 Gy (V 20) and at low dose region using various designs of the fan-shaped complete block (FSCB) in helical tomotherapy. Hypothetical esophageal tumor was delineated on an anthropomorphic phantom. The FSCB was defined as the fan-shaped radiation restricted area located in both lungs. Seven treatment plans were performed with nonblock design and FSCB with different fan angles, that is, from 90° to 140°, with increment of 10°. The homogeneous index, conformation number, MLD, and the relative lung volume receiving more than 5, 10, 15, and 20 Gy (V 5, V 10, V 15, and V 20) were determined for each treatment scheme. There was a substantial reduction in the MLD, V 5, V 10, V 15, and V 20 when using different types of FSCB as compared to the nonblock design. The reduction of V 20, V 15, V 10, and V 5 was 6.3%-8.6%, 16%-23%, 42%-57%, and 42%-66% for FSCB 90°-140°, respectively. The use of FSCB in helical tomotherapy is a promising method to reduce the MLD, V 20, and relative lung volume in low dose region, especially in V 5 and V 10 for esophageal cancer.

A study of longitudinal tumor motion in helical tomotherapy using a cylindrical phantom

PubMed Central

Klein, Michael; Gaede, Stewart

2013-01-01

Tumor motion during radiation treatment on a helical tomotherapy unit may create problems due to interplay with motion of the multileaf collimator, gantry rotation, and patient couch translation through the gantry. This study evaluated this interplay effect for typical clinical parameters using a cylindrical phantom consisting of 1386 diode detectors placed on a respiratory motion platform. All combinations of radiation field widths (1, 2.5, and 5 cm) and gantry rotation periods (16, 30, and 60 s) were considered for sinusoidal motions with a period of 4 s and amplitudes of 5, 6, 7, 8, 9, and 10 mm, as well as real patient breathing pattern. Gamma comparisons with 2% dose difference and 2 mm distance to agreement and dose profiles were used for evaluation. The required motion margins were determined for each set of parameters. The required margin size increased with decreasing field width and increasing tumor motion amplitude, but was not affected by rotation period. The plans with the smallest field width of 1 cm have required motion margins approximately equal to the amplitude of motion (±25%), while those with the largest field width of 5 cm had required motion margins approximately equal to 20% of the motion amplitude (±20%). For tumor motion amplitudes below 6 mm and field widths above 1 cm, the required additional motion margins were very small, at a maximum of 2.5 mm for sinusoidal breathing patterns and 1.2 mm for the real patient breathing pattern. PACS numbers: 87.55.km, 87.55.Qr, 87.56.Fc

Treatment of folliculitis decalvans using intensity-modulated radiation via tomotherapy.

PubMed

Elsayad, Khaled; Kriz, Jan; Haverkamp, Uwe; Plachouri, Kerasia-Maria; Jeskowiak, Antonia; Sunderkötter, Cord; Eich, Hans Theodor

2015-11-01

Folliculitis decalvans (FD) is a form of primary neutrophilic scarring alopecia that is characterized clinically by chronic suppurative folliculitis and often associated with pruritus or even pain. Treatment of FD is often difficult. Herein, we report a case of recalcitrant and painful folliculitis decalvans refractory to antibiotic and anti-inflammatory therapies, which was successfully treated by intensity-modulated radiotherapy (IMRT) in order to irreversibly eliminate hair follicles that prove to be one etiological trigger. A 45-year-old male patient with a refractory FD presented with a crusting suppurative folliculitis and atrophic scarring patches on the scalp associated with pain and pruritus. We attempted relief of symptoms by reducing scalp inflammation and eliminating hair follicles through radiation. We delivered 11.0 Gy in two radiation series using tomotherapy, 5.0 Gy in 5 equivalent fractions as a first radiation course. The symptoms markedly decreased but did not totally disappear. Therefore, we delivered a second radiation series 4 months later with an additional 6 Gy. This led to almost complete epilation on the scalp and abolished pain and pruritus on the capillitium. The patient was regularly followed up until 26 months after radiotherapy. Draining lesions or exudation did not recur. He only experienced discrete hair regrowth in the occipital region with folliculitis 12 months after radiotherapy. These residual lesions are currently treated with laser epilation therapy. A radical approach to eliminating hair follicles by repeated radiation therapy may induce lasting relief of symptoms in chronic suppurative FD associated with persistent trichodynia.

Medical physics practice in the next decade

PubMed Central

Paliwal, Bhudatt

2006-01-01

Impressive advances in computers and materials science have fueled a broad-based confluence of basic science breakthroughs. These advances are making us reformulate our learning, teaching and credentialing methodologies and research and development frontiers. We are now in the age of molecular medicine. In the entire field of health care, a paradigm shift from population-based solutions to individual specific care is taking place. These trends are reshaping the practice of medical physics. In this short presentation, examples are given to illustrate developments in image-guided intensity-modulated and adaptive helical tomotherapy, enhanced application of intensity modulation radiotherapy (IMRT) using adaptive radiotherapy and conformal avoidance. These advances include improved normal tissue sparing and permit dose reconstruction and verification, thereby allowing significant biologically effective dose escalation and reduced radiation toxicity. The intrinsic capability of helical TomoTherapy for megavoltage CT imaging for IMRT image-guidance is also discussed. Finally developments in motion management are described. PMID:22275799

Investigating output and energy variations and their relationship to delivery QA results using Statistical Process Control for helical tomotherapy.

PubMed

Binny, Diana; Mezzenga, Emilio; Lancaster, Craig M; Trapp, Jamie V; Kairn, Tanya; Crowe, Scott B

2017-06-01

The aims of this study were to investigate machine beam parameters using the TomoTherapy quality assurance (TQA) tool, establish a correlation to patient delivery quality assurance results and to evaluate the relationship between energy variations detected using different TQA modules. TQA daily measurement results from two treatment machines for periods of up to 4years were acquired. Analyses of beam quality, helical and static output variations were made. Variations from planned dose were also analysed using Statistical Process Control (SPC) technique and their relationship to output trends were studied. Energy variations appeared to be one of the contributing factors to delivery output dose seen in the analysis. Ion chamber measurements were reliable indicators of energy and output variations and were linear with patient dose verifications. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Surface dose measurement for helical tomotherapy.

PubMed

Snir, Jonatan A; Mosalaei, Homeira; Jordan, Kevin; Yartsev, Slav

2011-06-01

To compare the surface dose measurements made by different dosimeters for the helical tomotherapy (HT) plan in the case of the target close to the surface. Surface dose measurements in different points for the HT plan to deliver 2 Gy to the planning target volume (PTV) at 5 mm below the surface of the cylindrical phantom were performed by radiochromic films, single use metal oxide semiconductor field-effect transistor (MOSFET) dosimeters, silicon IVD QED diode, and optically stimulated luminescence (OSL) dosimeters. The measured doses by all dosimeters were within 12 +/- 8% difference of each other. Radiochromic films, EBT, and EBT2, provide high spatial resolution, although it is difficult to get accurate measurements of dose. Both the OSL and QED measured similar dose to that of the MOSFET detectors. The QED dosimeter is promising as a reusable on-line wireless dosimeter, while the OSL dosimeters are easier to use, require minimum setup time and are very precise.

Radiobiological and treatment planning study of a simultaneously integrated boost for canine nasal tumors using helical tomotherapy.

PubMed

Gutíerrez, Alonso N; Deveau, Michael; Forrest, Lisa J; Tomé, Wolfgang A; Mackie, Thomas R

2007-01-01

Feasibility of delivering a simultaneously integrated boost to canine nasal tumors using helical tomotherapy to improve tumor control probability (TCP) via an increase in total biological equivalent uniform dose (EUD) was evaluated. Eight dogs with varying size nasal tumors (5.8-110.9 cc) were replanned to 42 Gy to the nasal cavity and integrated dose boosts to gross disease of 45.2, 48.3, and 51.3 Gy in 10 fractions. EUD values were calculated for tumors and mean normalized total doses (NTD(mean)) for organs at risk (OAR). Normal Tissue Complication Probability (NTCP) values were obtained for OARs, and estimated TCP values were computed using a logistic dose-response model and based on deliverable EUD boost doses. Significant increases in estimated TCP to 54%, 74%, and 86% can be achieved with 10%, 23%, and 37% mean relative EUD boosts to the gross disease, respectively. NTCP values for blindness of either eye and for brain necrosis were < 0.01% for all boosts. Values for cataract development were 31%, 42%, and 46% for studied boost schemas, respectively. Average NTD(mean) to eyes and brain for mean EUD boosts were 10.2, 11.3, and 12.1 Gy3, and 7.5, 7.2, and 7.9 Gy2, respectively. Using helical tomotherapy, simultaneously integrated dose boosts can be delivered to increase the estimated TCP at 1-year without significantly increasing the NTD(mean) to eyes and brain. Delivery of these treatments in a prospective trial may allow quantification of a dose-response relationship in canine nasal tumors.

Protection of quality and innovation in radiation oncology: the prospective multicenter trial QUIRO of DEGRO: evaluation of time, attendance of medical staff, and resources during radiotherapy with tomotherapy.

PubMed

Winkler, Cornelia; Duma, M N; Popp, W; Sack, H; Budach, V; Molls, M; Kampfer, S

2014-10-01

The technical progress in radiotherapy in recent years has been tremendous. This also implies a change of human and time resources. However, there is a lack of data on this topic. Therefore, the DEGRO initiated several studies in the QUIRO project on this subject. The present publication focuses on results for tomotherapy systems and compares them with other IMRT techniques. Over a period of several months, time allocation was documented using a standard form at two university hospitals. The required time for individual steps in the treatment planning process was recorded for all involved professional groups (physicist, technician, and physician) by themselves. The time monitoring at the treatment machines was performed by auxiliary employees (student research assistants). Evaluation of the data was performed for all recorded data as well as by tumor site. A comparison was made between the two involved institutions. A total of 1,691 records were analyzed: 148 from head and neck (H&N) tumors, 460 from prostate cancer, 136 from breast cancer, and 947 from other tumor entities. The mean value of all data from both centers for the definition of the target volumes for H&N tumors took a radiation oncology specialist 75 min, while a physicist needed for the physical treatment planning 214 min. For prostate carcinomas, the times were 60 and 147 min, respectively, and for the group of other entities 63 and 192 min, respectively. For the first radiation treatment, the occupancy time of the linear accelerator room was 31, 26, and 30 min for each entity (H&N, prostate, other entities, respectively). For routine treatments 22, 18, and 21 min were needed for the particular entities. Major differences in the time required for the individual steps were observed between the two centers. This study gives an overview of the time and personnel requirements in radiation therapy using a tomotherapy system. The most representative analysis could be done for the room occupancy times during treatment in both centers. Due to the partly small amount of data and differing planning workflows between the two centers, it is problematic to draw a firm conclusion with regard to planning times. Overall, the time required for the tomotherapy treatment and planning is slightly higher compared to other IMRT techniques.

Single‐fraction spine SBRT end‐to‐end testing on TomoTherapy, Vero, TrueBeam, and CyberKnife treatment platforms using a novel anthropomorphic phantom

PubMed Central

Kaufman, Isaac; Powell, Rachel; Pandya, Shalini; Somnay, Archana; Bossenberger, Todd; Ramirez, Ezequiel; Reynolds, Robert; Solberg, Timothy; Burmeister, Jay

2015-01-01

Spine SBRT involves the delivery of very high doses of radiation to targets adjacent to the spinal cord and is most commonly delivered in a single fraction. Highly conformal planning and accurate delivery of such plans is imperative for successful treatment without catastrophic adverse effects. End–to‐end testing is an important practice for evaluating the entire treatment process from simulation through treatment delivery. We performed end‐to‐end testing for a set of representative spine targets planned and delivered using four different treatment planning systems (TPSs) and delivery systems to evaluate the various capabilities of each. An anthropomorphic E2E SBRT phantom was simulated and treated on each system to evaluate agreement between measured and calculated doses. The phantom accepts ion chambers in the thoracic region and radiochromic film in the lumbar region. Four representative targets were developed within each region (thoracic and lumbar) to represent different presentations of spinal metastases and planned according to RTOG 0631 constraints. Plans were created using the TomoTherapy TPS for delivery using the Hi·Art system, the iPlan TPS for delivery using the Vero system, the Eclipse TPS for delivery using the TrueBeam system in both flattened and flattening filter free (FFF), and the MultiPlan TPS for delivery using the CyberKnife system. Delivered doses were measured using a 0.007 cm3 ion chamber in the thoracic region and EBT3 GAFCHROMIC film in the lumbar region. Films were scanned and analyzed using an Epson Expression 10000XL flatbed scanner in conjunction with FilmQAPro2013. All treatment platforms met all dose constraints required by RTOG 0631. Ion chamber measurements in the thoracic targets delivered an overall average difference of 1.5%. Specifically, measurements agreed with the TPS to within 2.2%, 3.2%, 1.4%, 3.1%, and 3.0% for all three measureable cases on TomoTherapy, Vero, TrueBeam (FFF), TrueBeam (flattened), and CyberKnife, respectively. Film measurements for the lumbar targets resulted in average global gamma index passing rates of 100% at 3%/3 mm, 96.9% at 2%/2 mm, and 61.8% at 1%/1 mm, with a 10% minimum threshold for all plans on all platforms. Local gamma analysis was also performed with similar results. While gamma passing rates were consistently accurate across all platforms through 2%/2 mm, treatment beam‐on delivery times varied greatly between each platform with TrueBeam FFF being shortest, averaging 4.4 min, TrueBeam using flattened beam at 9.5 min, TomoTherapy at 30.5 min, Vero at 19 min, and CyberKnife at 46.0 min. In spite of the complexity of the representative targets and their proximity to the spinal cord, all treatment platforms were able to create plans meeting all RTOG 0631 dose constraints and produced exceptional agreement between calculated and measured doses. However, there were differences in the plan characteristics and significant differences in the beam‐on delivery time between platforms. Thus, clinical judgment is required for each particular case to determine most appropriate treatment planning/delivery platform. PACS number: 87.53.Ly PMID:25679169

The role of helical tomotherapy in the treatment of bone plasmacytoma.

PubMed

Chargari, Cyrus; Hijal, Tarek; Bouscary, Didier; Caussa, Lucas; Dendale, Remi; Zefkili, Sofia; Fourquet, Alain; Kirova, Youlia M

2012-01-01

We evaluated the early clinical outcome of patients with solitary bone plasmacytoma (SP) or a solitary lesion of multiple myeloma (MM) treated with helical tomotherapy (HT) compared with 3D conformal radiotherapy (3D-CRT), in terms of target coverage and exposure of critical organs. Ten patients with SP and 3 patients with a solitary lesion of MM underwent radiation therapy (RT) delivered by HT, to a dose of 40 Gy in 20 fractions. Treatment planning was then performed with 3D-CRT and the dosimetric parameters of both techniques were compared. Patients were also assessed for response to treatment and acute toxicities. With a median follow-up of 13 months, 78% of patients with pain before RT had resolution of their symptoms. Coverage of target lesion was adequate with both techniques in 12 of 13 patients. Target coverage was significantly lower for HT (V(95%) = 98.55% vs. 97.15%; p = 0.04, for 3D-CRT and HT, respectively). Target overdoses were also lower with HT (V(105%) = 2.01% vs. 0.19%; p= 0.16), although nonsignificant. Finally, there were no significant differences in organs-at-risk irradiation between both techniques. The early treatment tolerance was excellent, with no toxicity higher than grade I. RT of SP and MM with a solitary lesion can be safely delivered with HT, with no major acute side effects and good symptomatic control. Finally, HT provides a dosimetry similar to that of 3D-CRT in terms of organs-at-risk sparing and target volume coverage. Copyright © 2012 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

The use of megavoltage CT (MVCT) images for dose recomputations

NASA Astrophysics Data System (ADS)

Langen, K. M.; Meeks, S. L.; Poole, D. O.; Wagner, T. H.; Willoughby, T. R.; Kupelian, P. A.; Ruchala, K. J.; Haimerl, J.; Olivera, G. H.

2005-09-01

Megavoltage CT (MVCT) images of patients are acquired daily on a helical tomotherapy unit (TomoTherapy, Inc., Madison, WI). While these images are used primarily for patient alignment, they can also be used to recalculate the treatment plan for the patient anatomy of the day. The use of MVCT images for dose computations requires a reliable CT number to electron density calibration curve. In this work, we tested the stability of the MVCT numbers by determining the variation of this calibration with spatial arrangement of the phantom, time and MVCT acquisition parameters. The two calibration curves that represent the largest variations were applied to six clinical MVCT images for recalculations to test for dosimetric uncertainties. Among the six cases tested, the largest difference in any of the dosimetric endpoints was 3.1% but more typically the dosimetric endpoints varied by less than 2%. Using an average CT to electron density calibration and a thorax phantom, a series of end-to-end tests were run. Using a rigid phantom, recalculated dose volume histograms (DVHs) were compared with plan DVHs. Using a deformed phantom, recalculated point dose variations were compared with measurements. The MVCT field of view is limited and the image space outside this field of view can be filled in with information from the planning kVCT. This merging technique was tested for a rigid phantom. Finally, the influence of the MVCT slice thickness on the dose recalculation was investigated. The dosimetric differences observed in all phantom tests were within the range of dosimetric uncertainties observed due to variations in the calibration curve. The use of MVCT images allows the assessment of daily dose distributions with an accuracy that is similar to that of the initial kVCT dose calculation.

Angiogenic Blockade and Radiotherapy in Hepatocellular Carcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chi, Kwan-Hwa, E-mail: M006565@ms.skh.org.t; Institute of Radiation Science and School of Medicine, National Yang-Ming University, Taipei, Taiwan; Liao, Chao-Sheng

2010-09-01

Purpose: We report our preliminary experience of combining sunitinib and helical tomotherapy in patients with advanced HCC. Methods and Materials: Records of patients with advanced hepatocellular carcinoma (HCC) treated with helical tomotherapy and sunitinib after radiation therapy (RT) from March 2007 to August 2008 were retrospectively reviewed. We report acute toxicities, radiologic response, serial {alpha}-fetoprotein (AFP) kinetics, and survival. Results: Of 23 evaluable patients, 60% had {>=}2 hepatic lesions, extrahepatic disease was present in 5 (21.7%), and all received 2 tablets (25 mg) of sunitinib at least 1 week before, during, and 2 weeks after RT. Thirteen patients continued maintenancemore » sunitinib after RT until disease progression. Hypofractionated RT with a median target dose of 52.5 Gy/15 fractions was delivered. An objective response was achieved in 74% of patients. The 1-year survival rate was 70%, with median survival of 16 months. Multivariate analysis showed that maintenance sunitinib was the most significant factor for survival. The time to progression was 10 months in the maintenance group compared with 4 months in the control group. Eighteen out of 21 patients with elevated AFP (85.7%) had {>=}50% decline of AFP within 2 months after RT. There were three episodes of upper gastrointestinal bleeding and one episode of pancreatitis; 10 patients had {>=}Grade 2 elevation of liver enzymes, and 15 had {>=}Grade 2 thrombocytopenia. Conclusions: These preliminary results suggest that sunitinib and helical tomotherapy yield high Response Evaluation Criteria in Solid Tumors (RECIST) and AFP response rates in advanced HCC with an acceptable safety profile. Maintenance sunitinib after RT potentially prolongs survival. A randomized trial is warranted.« less

Peripheral Dose Heterogeneity Due to the Thread Effect in Total Marrow Irradiation With Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takahashi, Yutaka; Verneris, Michael R.; Dusenbery, Kathryn E.

Purpose: To report potential dose heterogeneity leading to underdosing at different skeletal sites in total marrow irradiation (TMI) with helical tomotherapy due to the thread effect and provide possible solutions to reduce this effect. Methods and Materials: Nine cases were divided into 2 groups based on patient size, defined as maximum left-to-right arm distance (mLRD): small mLRD (≤47 cm) and large mLRD (>47 cm). TMI treatment planning was conducted by varying the pitch and modulation factor while a jaw size (5 cm) was kept fixed. Ripple amplitude, defined as the peak-to-trough dose relative to the average dose due to themore » thread effect, and the dose–volume histogram (DVH) parameters for 9 cases with various mLRD was analyzed in different skeletal regions at off-axis (eg, bones of the arm or femur), at the central axis (eg, vertebrae), and planning target volume (PTV), defined as the entire skeleton plus 1-cm margin. Results: Average ripple amplitude for a pitch of 0.430, known as one of the magic pitches that reduce thread effect, was 9.2% at 20 cm off-axis. No significant differences in DVH parameters of PTV, vertebrae, or femur were observed between small and large mLRD groups for a pitch of ≤0.287. Conversely, in the bones of the arm, average differences in the volume receiving 95% and 107% dose (V95 and V107, respectively) between large and small mLRD groups were 4.2% (P=.016) and 16% (P=.016), respectively. Strong correlations were found between mLRD and ripple amplitude (rs=.965), mLRD and V95 (rs=−.742), and mLRD and V107 (rs=.870) of bones of the arm. Conclusions: Thread effect significantly influences DVH parameters in the bones of the arm for large mLRD patients. By implementing a favorable pitch value and adjusting arm position, peripheral dose heterogeneity could be reduced.« less

Multi-institutional Feasibility Study of a Fast Patient Localization Method in Total Marrow Irradiation With Helical Tomotherapy: A Global Health Initiative by the International Consortium of Total Marrow Irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takahashi, Yutaka; Vagge, Stefano; Agostinelli, Stefano

2015-01-01

Purpose: To develop, characterize, and implement a fast patient localization method for total marrow irradiation. Methods and Materials: Topographic images were acquired using megavoltage computed tomography (MVCT) detector data by delivering static orthogonal beams while the couch traversed through the gantry. Geometric and detector response corrections were performed to generate a megavoltage topogram (MVtopo). We also generated kilovoltage topograms (kVtopo) from the projection data of 3-dimensional CT images to reproduce the same geometry as helical tomotherapy. The MVtopo imaging dose and the optimal image acquisition parameters were investigated. A multi-institutional phantom study was performed to verify the image registration uncertainty. Forty-fivemore » MVtopo images were acquired and analyzed with in-house image registration software. Results: The smallest jaw size (front and backup jaws of 0) provided the best image contrast and longitudinal resolution. Couch velocity did not affect the image quality or geometric accuracy. The MVtopo dose was less than the MVCT dose. The image registration uncertainty from the multi-institutional study was within 2.8 mm. In patient localization, the differences in calculated couch shift between the registration with MVtopo-kVtopo and MVCT-kVCT images in lateral, cranial–caudal, and vertical directions were 2.2 ± 1.7 mm, 2.6 ± 1.4 mm, and 2.7 ± 1.1 mm, respectively. The imaging time in MVtopo acquisition at the couch speed of 3 cm/s was <1 minute, compared with ≥15 minutes in MVCT for all patients. Conclusion: Whole-body MVtopo imaging could be an effective alternative to time-consuming MVCT for total marrow irradiation patient localization.« less

Safety and feasibility of STAT RAD: Improvement of a novel rapid tomotherapy-based radiation therapy workflow by failure mode and effects analysis.

PubMed

Jones, Ryan T; Handsfield, Lydia; Read, Paul W; Wilson, David D; Van Ausdal, Ray; Schlesinger, David J; Siebers, Jeffrey V; Chen, Quan

2015-01-01

The clinical challenge of radiation therapy (RT) for painful bone metastases requires clinicians to consider both treatment efficacy and patient prognosis when selecting a radiation therapy regimen. The traditional RT workflow requires several weeks for common palliative RT schedules of 30 Gy in 10 fractions or 20 Gy in 5 fractions. At our institution, we have created a new RT workflow termed "STAT RAD" that allows clinicians to perform computed tomographic (CT) simulation, planning, and highly conformal single fraction treatment delivery within 2 hours. In this study, we evaluate the safety and feasibility of the STAT RAD workflow. A failure mode and effects analysis (FMEA) was performed on the STAT RAD workflow, including development of a process map, identification of potential failure modes, description of the cause and effect, temporal occurrence, and team member involvement in each failure mode, and examination of existing safety controls. A risk probability number (RPN) was calculated for each failure mode. As necessary, workflow adjustments were then made to safeguard failure modes of significant RPN values. After workflow alterations, RPN numbers were again recomputed. A total of 72 potential failure modes were identified in the pre-FMEA STAT RAD workflow, of which 22 met the RPN threshold for clinical significance. Workflow adjustments included the addition of a team member checklist, changing simulation from megavoltage CT to kilovoltage CT, alteration of patient-specific quality assurance testing, and allocating increased time for critical workflow steps. After these modifications, only 1 failure mode maintained RPN significance; patient motion after alignment or during treatment. Performing the FMEA for the STAT RAD workflow before clinical implementation has significantly strengthened the safety and feasibility of STAT RAD. The FMEA proved a valuable evaluation tool, identifying potential problem areas so that we could create a safer workflow. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Stability of the Helical TomoTherapy Hi·Art II detector for treatment beam irradiations

PubMed Central

Schombourg, Karin; Bochud, François

2014-01-01

The Hi·Art II Helical TomoTherapy (HT) unit is equipped with a built‐in onboard MVCT detector used for patient imaging and beam monitoring. Our aim was to study the detector stability for treatment beam measurements. We studied the MVCT detector response with the 6 MV photon beam over time, throughout short‐term (during an irradiation) and long‐term (two times 50 days) periods. Our results show a coefficient of variation ≤1% for detector chambers inside the beam (excluding beam gradients) for short‐ and long‐term response of the MVCT detector. Larger variations were observed in beam gradients and an influence of the X‐ray target where degradation was found. The results assume that an ‘air scan’ procedure is performed daily to recalibrate the detector with the imaging beam. On short term, the detector response stability is comparable to other devices. Long‐term measurements during two 50‐day periods show a good reproducibility. PACS numbers: 87.55.ne, 87.55.Qr PMID:25493514

Adjuvant helical IMRT by tomotherapy for bulky adrenocortical carcinoma operated with positive margins: a case report.

PubMed

Delmastro, Elena; Garibaldi, Elisabetta; Gabriele, Domenico; Bresciani, Sara; Cattari, Gabriella; Dia, Amalia Di; Manini, Claudia; Collura, Devis; Redda, Maria Grazia Ruo; Gabriele, Pietro

2016-11-11

Adrenocortical carcinoma (ACC) is a rare tumor in the adult. The main therapy is surgery but in some cases radiotherapy may be needed to control the disease locally. A patient with a surgically removed bulky ACC and pathologic finding of a positive margin was treated at our center by adjuvant mitotane and radiotherapy using an intensity-modulated radiation therapy (IMRT)/image-guided radiotherapy (IGRT) technique by tomotherapy. Dose prescriptions were 63 Gy on the surgical bed and 50.4 Gy on the lymphatic drainage in 28 sessions. Patient compliance was good with no evidence of acute or late toxicities. Thirty months after radiotherapy, the patient is alive without evidence of disease checked by 18F-fluorodeoxyglucose positron emission tomography/computed tomography and without any complication. In patients with adverse prognostic features, the delivery of adequate adjuvant radiotherapy doses with IMRT and daily IGRT is feasible and safe and could result in an improved outcome for patients with ACC.

Early Experience of Helical Tomotherapy for Hepatobiliary Radiotherapy

PubMed Central

Massabeau, Carole; Marchand, Virginie; Zefkili, Sofia; Servois, Vincent; Campana, François; Giraud, Philippe

2011-01-01

Helical tomotherapy (HT), an image-guided, intensity-modulated, radiation therapy technique, allows for precise targeting while sparing normal tissues. We retrospectively assessed the feasibility and tolerance of the hepatobiliary HT in 9 patients. A total dose of 54 to 60 Gy was prescribed (1.8 or 2 Gy per fraction) with concurrent capecitabine for 7 patients. There were 1 hepatocarcinoma, 3 cholangiocarcinoma, 4 liver metastatic patients, and 1 pancreatic adenocarcinoma. All but one patient received previous therapies (chemotherapy, liver radiofrequency, and/or surgery). The median doses delivered to the normal liver and to the right kidney were 15.7 Gy and 4.4 Gy, respectively, below the recommended limits for all patients. Most of the treatment-related adverse events were transient and mild in severity. With a median followup of 12 months, no significant late toxicity was noted. Our results suggested that HT could be safely incorporated into the multidisciplinary treatment of hepatobiliary or pancreatic malignant disease. PMID:25954545

Tomotherapy as a tool in image-guided radiation therapy (IGRT): theoretical and technological aspects

PubMed Central

Yartsev, S; Kron, T; Van Dyk, J

2007-01-01

Helical tomotherapy (HT) is a novel treatment approach that combines Intensity-Modulate Radiation Therapy (IMRT) delivery with in-built image guidance using megavoltage (MV) CT scanning. The technique utilises a 6 MV linear accelerator mounted on a CT type ring gantry. The beam is collimated to a fan beam, which is intensity modulated using a binary multileaf collimator (MLC). As the patient advances slowly through the ring gantry, the linac rotates around the patient with a leaf-opening pattern optimised to deliver a highly conformal dose distribution to the target in the helical beam trajectory. The unit also allows the acquisition of MVCT images using the same radiation source detuned to reduce its effective energy to 3.5 MV, making the dose required for imaging less than 3 cGy. This paper discusses the major features of HT and describes the advantages and disadvantages of this approach in the context of the commercial Hi-ART system. PMID:21614257

Evaluation of tomotherapy MVCT image enhancement program for tumor volume delineation

PubMed Central

Martin, Spencer; Rodrigues, George; Chen, Quan; Pavamani, Simon; Read, Nancy; Ahmad, Belal; Hammond, J. Alex; Venkatesan, Varagur; Renaud, James

2011-01-01

The aims of this study were to investigate the variability between physicians in delineation of head and neck tumors on original tomotherapy megavoltage CT (MVCT) studies and corresponding software enhanced MVCT images, and to establish an optimal approach for evaluation of image improvement. Five physicians contoured the gross tumor volume (GTV) for three head and neck cancer patients on 34 original and enhanced MVCT studies. Variation between original and enhanced MVCT studies was quantified by DICE coefficient and the coefficient of variance. Based on volume of agreement between physicians, higher correlation in terms of average DICE coefficients was observed in GTV delineation for enhanced MVCT for patients 1, 2, and 3 by 15%, 3%, and 7%, respectively, while delineation variance among physicians was reduced using enhanced MVCT for 12 of 17 weekly image studies. Enhanced MVCT provides advantages in reduction of variance among physicians in delineation of the GTV. Agreement on contouring by the same physician on both original and enhanced MVCT was equally high. PACS numbers: 87.57.N‐, 87.57.np, 87.57.nt

The implication of non-cyclic intrafractional longitudinal motion in SBRT by TomoTherapy

NASA Astrophysics Data System (ADS)

Yang, Wensha; Van Ausdal, Ray; Read, Paul; Larner, James; Benedict, Stan; Sheng, Ke

2009-05-01

To determine the dosimetric impact of non-cyclic longitudinal intrafractional motion, TomoTherapy plans with different field sizes were interrupted during a phantom delivery, and a displacement between -5 mm and 5 mm was induced prior to the delivery of the completion procedure. The planar dose was measured by film and a cylindrical phantom, and under-dosed or over-dosed volume was observed for either positive or negative displacement. For a 2.5 cm field, there was a 4% deviation for every mm of motion and for a 1 cm field, the deviation was 8% per mm. The dimension of the under/over-dosed area was independent of the motion but dependent on the field size. The results have significant implication in small-field high-dose treatments (i.e. stereotactic body radiation therapy (SBRT)) that deliver doses in only a few fractions. Our studies demonstrate that a small longitudinal motion may cause a dose error that is difficult to compensate; however, dividing a SBRT fraction into smaller passes is helpful to reduce such adverse effects.

Effects of dose scaling on delivery quality assurance in tomotherapy

PubMed Central

Nalichowski, Adrian; Burmeister, Jay

2012-01-01

Delivery quality assurance (DQA) of tomotherapy plans is routinely performed with silver halide film which has a limited range due to the effects of saturation. DQA plans with dose values exceeding this limit require the dose of the entire plan to be scaled downward if film is used, to evaluate the dose distribution in two dimensions. The potential loss of fidelity between scaled and unscaled DQA plans as a function of dose scaling is investigated. Three treatment plans for 12 Gy fractions designed for SBRT of the lung were used to create DQA procedures that were scaled between 100% and 10%. The dose was measured with an ionization chamber array and compared to values from the tomotherapy treatment planning system. Film and cylindrical ion chamber measurements were also made for one patient for scaling factors of 50% to 10% to compare with the ionization chamber array measurements. The array results show the average gamma pass rate is ≥99% from 100% to 30% scaling. The average gamma pass rate falls to 93.6% and 51.1% at 20% and 10% scaling, respectively. Film analysis yields similar pass rates. Cylindrical ion chambers did not exhibit significant variation with dose scaling, but only represent points in the low gradient region of the dose distribution. Scaling the dose changes the mechanics of the radiation delivery, as well as the signal‐to‐noise ratio. Treatment plans which exhibit parameters that differ significantly from those common to DQA plans studied in this paper may exhibit different behavior. Dose scaling should be limited to the smallest degree possible. Planar information, such as that from film or a detector array, is required. The results show that it is not necessary to perform both a scaled and unscaled DQA plan for the treatment plans considered here. PACS numbers: 87.55.km, 87.55.Qr PMID:22231213

Postmastectomy radiotherapy with integrated scar boost using helical tomotherapy.

PubMed

Rong, Yi; Yadav, Poonam; Welsh, James S; Fahner, Tasha; Paliwal, Bhudatt

2012-01-01

The purpose of this study was to evaluate helical tomotherapy dosimetry in postmastectomy patients undergoing treatment for chest wall and positive nodal regions with simultaneous integrated boost (SIB) in the scar region using strip bolus. Six postmastectomy patients were scanned with a 5-mm-thick strip bolus covering the scar planning target volume (PTV) plus 2-cm margin. For all 6 cases, the chest wall received a total cumulative dose of 49.3-50.4 Gy with daily fraction size of 1.7-2.0 Gy. Total dose to the scar PTV was prescribed to 58.0-60.2 Gy at 2.0-2.5 Gy per fraction. The supraclavicular PTV and mammary nodal PTV received 1.7-1.9 dose per fraction. Two plans (with and without bolus) were generated for all 6 cases. To generate no-bolus plans, strip bolus was contoured and overrode to air density before planning. The setup reproducibility and delivered dose accuracy were evaluated for all 6 cases. Dose-volume histograms were used to evaluate dose-volume coverage of targets and critical structures. We observed reduced air cavities with the strip bolus setup compared with what we normally see with the full bolus. The thermoluminescence dosimeters (TLD) in vivo dosimetry confirmed accurate dose delivery beneath the bolus. The verification plans performed on the first day megavoltage computed tomography (MVCT) image verified that the daily setup and overall dose delivery was within 2% accuracy compared with the planned dose. The hotspot of the scar PTV in no-bolus plans was 111.4% of the prescribed dose averaged over 6 cases compared with 106.6% with strip bolus. With a strip bolus only covering the postmastectomy scar region, we observed increased dose uniformity to the scar PTV, higher setup reproducibility, and accurate dose delivered beneath the bolus. This study demonstrates the feasibility of using a strip bolus over the scar using tomotherapy for SIB dosimetry in postmastectomy treatments. Published by Elsevier Inc.

Postmastectomy radiotherapy with integrated scar boost using helical tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rong Yi, E-mail: rong@humonc.wisc.edu; University of Wisconsin Riverview Cancer Center, Wisconsin Rapids, WI; Yadav, Poonam

2012-10-01

The purpose of this study was to evaluate helical tomotherapy dosimetry in postmastectomy patients undergoing treatment for chest wall and positive nodal regions with simultaneous integrated boost (SIB) in the scar region using strip bolus. Six postmastectomy patients were scanned with a 5-mm-thick strip bolus covering the scar planning target volume (PTV) plus 2-cm margin. For all 6 cases, the chest wall received a total cumulative dose of 49.3-50.4 Gy with daily fraction size of 1.7-2.0 Gy. Total dose to the scar PTV was prescribed to 58.0-60.2 Gy at 2.0-2.5 Gy per fraction. The supraclavicular PTV and mammary nodal PTVmore » received 1.7-1.9 dose per fraction. Two plans (with and without bolus) were generated for all 6 cases. To generate no-bolus plans, strip bolus was contoured and overrode to air density before planning. The setup reproducibility and delivered dose accuracy were evaluated for all 6 cases. Dose-volume histograms were used to evaluate dose-volume coverage of targets and critical structures. We observed reduced air cavities with the strip bolus setup compared with what we normally see with the full bolus. The thermoluminescence dosimeters (TLD) in vivo dosimetry confirmed accurate dose delivery beneath the bolus. The verification plans performed on the first day megavoltage computed tomography (MVCT) image verified that the daily setup and overall dose delivery was within 2% accuracy compared with the planned dose. The hotspot of the scar PTV in no-bolus plans was 111.4% of the prescribed dose averaged over 6 cases compared with 106.6% with strip bolus. With a strip bolus only covering the postmastectomy scar region, we observed increased dose uniformity to the scar PTV, higher setup reproducibility, and accurate dose delivered beneath the bolus. This study demonstrates the feasibility of using a strip bolus over the scar using tomotherapy for SIB dosimetry in postmastectomy treatments.« less

Can We Spare the Pancreas and Other Abdominal Organs at Risk? A Comparison of Conformal Radiotherapy, Helical Tomotherapy and Proton Beam Therapy in Pediatric Irradiation.

PubMed

Jouglar, Emmanuel; Wagner, Antoine; Delpon, Grégory; Campion, Loïc; Meingan, Philippe; Bernier, Valérie; Demoor-Goldschmidt, Charlotte; Mahé, Marc-André; Lacornerie, Thomas; Supiot, Stéphane

2016-01-01

Late abdominal irradiation toxicity during childhood included renal damage, hepatic toxicity and secondary diabetes mellitus. We compared the potential of conformal radiotherapy (CRT), helical tomotherapy (HT) and proton beam therapy (PBT) to spare the abdominal organs at risk (pancreas, kidneys and liver- OAR) in children undergoing abdominal irradiation. We selected children with abdominal tumors who received more than 10 Gy to the abdomen. Treatment plans were calculated in order to keep the dose to abdominal OAR as low as possible while maintaining the same planned target volume (PTV) coverage. Dosimetric values were compared using the Wilcoxon signed-rank test. The dose distribution of 20 clinical cases with a median age of 8 years (range 1-14) were calculated with different doses to the PTV: 5 medulloblastomas (36 Gy), 3 left-sided and 2 right-sided nephroblastomas (14.4 Gy to the tumor + 10.8 Gy boost to para-aortic lymphnodes), 1 left-sided and 4 right-sided or midline neuroblastomas (21 Gy) and 5 Hodgkin lymphomas (19.8 Gy to the para-aortic lymphnodes and spleen). HT significantly reduced the mean dose to the whole pancreas (WP), the pancreatic tail (PT) and to the ipsilateral kidney compared to CRT. PBT reduced the mean dose to the WP and PT compared to both CRT and HT especially in midline and right-sided tumors. PBT decreased the mean dose to the ispilateral kidney but also to the contralateral kidney and the liver compared to CRT. Low dose to normal tissue was similar or increased with HT whereas integral dose and the volume of normal tissue receiving at least 5 and 10 Gy were reduced with PBT compared to CRT and HT. In children undergoing abdominal irradiation therapy, proton beam therapy reduces the dose to abdominal OAR while sparing normal tissue by limiting low dose irradiation.

Toxicity and efficacy of salvage carbon 11-choline positron emission tomography/computed tomography-guided radiation therapy in patients with lymph node recurrence of prostate cancer.

PubMed

Fodor, Andrei; Berardi, Genoveffa; Fiorino, Claudio; Picchio, Maria; Busnardo, Elena; Kirienko, Margarita; Incerti, Elena; Dell'Oca, Italo; Cozzarini, Cesare; Mangili, Paola; Pasetti, Marcella; Calandrino, Riccardo; Gianolli, Luigi; Di Muzio, Nadia G

2017-03-01

To report the 3-year toxicity and outcomes of carbon 11 (11C)-choline-positron emission tomography (PET)/computed tomography (CT)-guided radiotherapy (RT), delivered via helical tomotherapy (HTT; Tomotherapy ® Hi-Art II ® Treatment System, Accuray Inc., Sunnyvale, CA, USA) after lymph node (LN) relapses in patients with prostate cancer. From January 2005 to March 2013, 81 patients with biochemical recurrence after surgery, with or without adjuvant/salvage RT or radical RT, and with evidence of LN 11C-choline-PET/CT pathological uptake, underwent HTT (median [range] prostate-specific antigen level 2.59 [0.61-187] ng/mL). Of the 81 patients, 72 were treated at the pelvic and/or lumbar-aortic LN chain with HTT at 51.8 Gy/28 fr and with simultaneous integrated boost to a median dose of 65.5 Gy on the pathological uptake sites detected by 11C-choline-PET/CT. Nine patients were treated without simultaneous integrated boost (50-65.5 Gy, 25-30 fr). With a median (range) follow-up of 36 (9-116) months, 91.4% of the patients had a PSA reduction 3 months after HTT. The 3-year overall, local relapse-free and clinical relapse-free survival rates were 80.0, 89.8 and 61.8%, respectively. The 3-year actuarial incidences of ≥grade 2 rectal and ≥grade 2 genitourinary toxicity were 6.6% (±2.9%) and 26.3% (±5.5%), respectively. A PSA nadir of ≥0.26 ng/mL (hazard ratio [HR] 3.6, 95% confidence interval [CI] 1.7-7.7; P = 0.001), extrapelvic 11C-choline-PET/CT-positive LN location (HR 2.4, 95% CI 0.9-6.4; P = 0.07), RT previous to HTT (HR 2.7; 95% CI 1.07-6.9, P = 0.04) and number of positive LNs (HR 1.13, 95% CI 1.04-1.22; P = 0.003) were the main predictors of clinical relapse after HTT. 11C-choline-PET/CT-guided HTT is safe and effective in the treatment of LN relapses of prostate cancer in previously treated patients. © 2016 The Authors BJU International © 2016 BJU International Published by John Wiley & Sons Ltd.

Total marrow irradiation using Helical TomoTherapy

NASA Astrophysics Data System (ADS)

Garcia-Fernandez, Lourdes Maria

Clinical dose response data of human tumours are limited or restricted to a radiation dose range determined by the level of toxicity to the normal tissues. This is the case for the most common disseminated plasma cell neoplasm, multiple myeloma, where the maximum dose deliverable to the entire bony skeleton using a standard total body irradiation (TBI) technique is limited to about 12 Gy. This study is part of scientific background of a phase I/II dose escalation clinical trial for multiple myeloma using image-guided intensity modulated radiotherapy (IG-IMRT) to deliver high dose to the entire volume of bone marrow with Helical TomoTherapy (HT). This relatively new technology can deliver highly conformal dose distributions to complex target shapes while reducing the dose to critical normal tissues. In this study tools for comparing and predicting the effectiveness of different approaches to total marrow irradiation (TMI) using HT were provided. The expected dose response for plasma cell neoplasms was computed and a radiobiological evaluation of different treatment cohorts in a dose escalating study was performed. Normal tissue complication probability (NTCP) and tumour control probability (TCP) models were applied to an actual TMI treatment plan for a patient and the implications of using different longitudinal field widths were assessed. The optimum dose was ˜39 Gy for which a predicted tumour control of 95% (+/-3%) was obtained, with a predicted 3% (0, 8%) occurrence of radiation pneumonitis. Tissue sparing was seen by using smaller field widths only in the organs of the head. This suggests it would be beneficial to use the small fields in the head only since using small fields for the whole treatment would lead to long treatment times. In TMI it may be necessary to junction two longitudinally adjacent treatment volumes to form a contiguous planning target volume PTV. For instance, this is the case when a different SUP-INF spatial resolution is required or when the PTV length exceeds the bed travel distance. In this work, the dosimetric challenges associated with junctioning longitudinally adjacent PTVs with HT were analyzed and the feasibility of PTV junctioning was demonstrated. The benefits of spatially dividing or splitting the treatment into a few sub-treatments along the longitudinal direction were also investigated.

MO-B-BRB-03: 3D Dosimetry in the Clinic: Validating Special Techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Juang, T.

Full three-dimensional (3D) dosimetry using volumetric chemical dosimeters probed by 3D imaging systems has long been a promising technique for the radiation therapy clinic, since it provides a unique methodology for dose measurements in the volume irradiated using complex conformal delivery techniques such as IMRT and VMAT. To date true 3D dosimetry is still not widely practiced in the community; it has been confined to centres of specialized expertise especially for quality assurance or commissioning roles where other dosimetry techniques are difficult to implement. The potential for improved clinical applicability has been advanced considerably in the last decade by themore » development of improved 3D dosimeters (e.g., radiochromic plastics, radiochromic gel dosimeters and normoxic polymer gel systems) and by improved readout protocols using optical computed tomography or magnetic resonance imaging. In this session, established users of some current 3D chemical dosimeters will briefly review the current status of 3D dosimetry, describe several dosimeters and their appropriate imaging for dose readout, present workflow procedures required for good dosimetry, and analyze some limitations for applications in select settings. We will review the application of 3D dosimetry to various clinical situations describing how 3D approaches can complement other dose delivery validation approaches already available in the clinic. The applications presented will be selected to inform attendees of the unique features provided by full 3D techniques. Learning Objectives: L. John Schreiner: Background and Motivation Understand recent developments enabling clinically practical 3D dosimetry, Appreciate 3D dosimetry workflow and dosimetry procedures, and Observe select examples from the clinic. Sofie Ceberg: Application to dynamic radiotherapy Observe full dosimetry under dynamic radiotherapy during respiratory motion, and Understand how the measurement of high resolution dose data in an irradiated volume can help understand interplay effects during TomoTherapy or VMAT. Titania Juang: Special techniques in the clinic and research Understand the potential for 3D dosimetry in validating dose accumulation in deformable systems, and Observe the benefits of high resolution measurements for precision therapy in SRS and in MicroSBRT for small animal irradiators Geoffrey S. Ibbott: 3D Dosimetry in end-to-end dosimetry QA Understand the potential for 3D dosimetry for end-to-end radiation therapy process validation in the in-house and external credentialing setting. Canadian Institutes of Health Research; L. Schreiner, Modus QA, London, ON, Canada; T. Juang, NIH R01CA100835.« less

MO-B-BRB-01: 3D Dosimetry in the Clinic: Background and Motivation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schreiner, L.

Full three-dimensional (3D) dosimetry using volumetric chemical dosimeters probed by 3D imaging systems has long been a promising technique for the radiation therapy clinic, since it provides a unique methodology for dose measurements in the volume irradiated using complex conformal delivery techniques such as IMRT and VMAT. To date true 3D dosimetry is still not widely practiced in the community; it has been confined to centres of specialized expertise especially for quality assurance or commissioning roles where other dosimetry techniques are difficult to implement. The potential for improved clinical applicability has been advanced considerably in the last decade by themore » development of improved 3D dosimeters (e.g., radiochromic plastics, radiochromic gel dosimeters and normoxic polymer gel systems) and by improved readout protocols using optical computed tomography or magnetic resonance imaging. In this session, established users of some current 3D chemical dosimeters will briefly review the current status of 3D dosimetry, describe several dosimeters and their appropriate imaging for dose readout, present workflow procedures required for good dosimetry, and analyze some limitations for applications in select settings. We will review the application of 3D dosimetry to various clinical situations describing how 3D approaches can complement other dose delivery validation approaches already available in the clinic. The applications presented will be selected to inform attendees of the unique features provided by full 3D techniques. Learning Objectives: L. John Schreiner: Background and Motivation Understand recent developments enabling clinically practical 3D dosimetry, Appreciate 3D dosimetry workflow and dosimetry procedures, and Observe select examples from the clinic. Sofie Ceberg: Application to dynamic radiotherapy Observe full dosimetry under dynamic radiotherapy during respiratory motion, and Understand how the measurement of high resolution dose data in an irradiated volume can help understand interplay effects during TomoTherapy or VMAT. Titania Juang: Special techniques in the clinic and research Understand the potential for 3D dosimetry in validating dose accumulation in deformable systems, and Observe the benefits of high resolution measurements for precision therapy in SRS and in MicroSBRT for small animal irradiators Geoffrey S. Ibbott: 3D Dosimetry in end-to-end dosimetry QA Understand the potential for 3D dosimetry for end-to-end radiation therapy process validation in the in-house and external credentialing setting. Canadian Institutes of Health Research; L. Schreiner, Modus QA, London, ON, Canada; T. Juang, NIH R01CA100835.« less

MO-B-BRB-02: 3D Dosimetry in the Clinic: IMRT Technique Validation in Sweden

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ceberg, S.

Full three-dimensional (3D) dosimetry using volumetric chemical dosimeters probed by 3D imaging systems has long been a promising technique for the radiation therapy clinic, since it provides a unique methodology for dose measurements in the volume irradiated using complex conformal delivery techniques such as IMRT and VMAT. To date true 3D dosimetry is still not widely practiced in the community; it has been confined to centres of specialized expertise especially for quality assurance or commissioning roles where other dosimetry techniques are difficult to implement. The potential for improved clinical applicability has been advanced considerably in the last decade by themore » development of improved 3D dosimeters (e.g., radiochromic plastics, radiochromic gel dosimeters and normoxic polymer gel systems) and by improved readout protocols using optical computed tomography or magnetic resonance imaging. In this session, established users of some current 3D chemical dosimeters will briefly review the current status of 3D dosimetry, describe several dosimeters and their appropriate imaging for dose readout, present workflow procedures required for good dosimetry, and analyze some limitations for applications in select settings. We will review the application of 3D dosimetry to various clinical situations describing how 3D approaches can complement other dose delivery validation approaches already available in the clinic. The applications presented will be selected to inform attendees of the unique features provided by full 3D techniques. Learning Objectives: L. John Schreiner: Background and Motivation Understand recent developments enabling clinically practical 3D dosimetry, Appreciate 3D dosimetry workflow and dosimetry procedures, and Observe select examples from the clinic. Sofie Ceberg: Application to dynamic radiotherapy Observe full dosimetry under dynamic radiotherapy during respiratory motion, and Understand how the measurement of high resolution dose data in an irradiated volume can help understand interplay effects during TomoTherapy or VMAT. Titania Juang: Special techniques in the clinic and research Understand the potential for 3D dosimetry in validating dose accumulation in deformable systems, and Observe the benefits of high resolution measurements for precision therapy in SRS and in MicroSBRT for small animal irradiators Geoffrey S. Ibbott: 3D Dosimetry in end-to-end dosimetry QA Understand the potential for 3D dosimetry for end-to-end radiation therapy process validation in the in-house and external credentialing setting. Canadian Institutes of Health Research; L. Schreiner, Modus QA, London, ON, Canada; T. Juang, NIH R01CA100835.« less

SU-E-J-17: Evaluation of Metal Artifact Reduction in MVCTs Using a Model Based Image Reconstruction Method.

PubMed

Paudel, M; MacKenzie, M; Fallone, B; Rathee, S

2012-06-01

To evaluate the performance of a model based image reconstruction in reducing metal artifacts in MVCT systems, and to compare with filtered-back projection (FBP) technique. Iterative maximum likelihood polychromatic algorithm for CT (IMPACT) is used with pair/triplet production process and the energy dependent response of detectors. The beam spectra for in-house bench-top and TomotherapyTM MVCT are modelled for use in IMPACT. The energy dependent gain of detectors is calculated using a constrained optimization technique and measured attenuation produced by 0 - 24 cm thick solid water slabs. A cylindrical (19 cm diameter) plexiglass phantom containing various central cylindrical inserts (relative electron density of 0.28-1.69) between two steel rods (2 cm diameter) is scanned in the bench-top [the bremsstrahlung radiation from 6 MeV electron beam passed through 4 cm solid water on the Varian Clinac 2300C] and TomotherapyTM MVCTs. The FBP reconstructs images from raw signal normalised to air scan and corrected for beam hardening using a uniform plexi-glass cylinder (20 cm diameter). IMPACT starts with FBP reconstructed seed image and reconstructs final image at 1.25 MeV in 150 iterations. FBP produces a visible dark shading in the image between two steel rods that becomes darker with higher density central insert causing 5-8 % underestimation of electron density compared to the case without the steel rods. In the IMPACT image the dark shading connecting the steel rods is nearly removed and the uniform background restored. The average attenuation coefficients of the inserts and the background are very close to the corresponding theoretical values at 1.25 MeV. The dark shading metal artifact due to beam hardening can be removed in MVCT using the iterative reconstruction algorithm such as IMPACT. However, the accurate modelling of detectors' energy dependent response and physical processes are crucial for successful implementation. Funding support for the research is obtained from "Vanier Canada Graduate Scholarship" and "Canadian Institute of Health Research". © 2012 American Association of Physicists in Medicine.

Dosimetric aspects of breast radiotherapy with three-dimensional and intensity-modulated radiotherapy helical tomotherapy planning modules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yadav, Poonam; Service of Radiation Therapy, University of Wisconsin Aspirus Cancer Center, Wisconsin Rapids, WI; Yan, Yue, E-mail: yyan5@mdanderson.org

In this work, we investigated the dosimetric differences between the intensity-modulated radiotherapy (IMRT) plans and the three-dimensional (3D) helical plans based on the TomoTherapy system. A total of 15 patients with supine setup were randomly selected from the data base. For patients with lumpectomy planning target volume (PTV), regional lymph nodes were also included as part of the target. For dose sparing, the significant differences between the helical IMRT and helical 3D were only found in the heart and contralateral breast. For the dose to the heart, helical IMRT reduced the maximum point dose by 6.98 Gy compared to themore » helical 3D plan (p = 0.01). For contralateral breast, the helical IMRT plans significantly reduced the maximum point dose by 5.6 Gy compared to the helical 3D plan. However, compared to the helical 3D plan, the helical IMRT plan increased the volume for lower dose (13.08% increase in V{sub 5} {sub Gy}, p = 0.01). In general, there are no significant differences in dose sparing between helical IMRT and helical 3D plans.« less

Poster — Thur Eve — 15: Improvements in the stability of the tomotherapy imaging beam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belec, J

2014-08-15

Use of helical TomoTherapy based MVCT imaging for adaptive planning requires the image values (HU) to remain stable over the course of treatment. In the past, the image value stability was suboptimal, which required frequent change to the image value to density calibration curve to avoid dose errors on the order of 2–4%. The stability of the image values at our center was recently improved by stabilizing the dose rate of the machine (dose control servo) and performing daily MVCT calibration corrections. In this work, we quantify the stability of the image values over treatment time by comparing patient treatmentmore » image density derived using MVCT and KVCT. The analysis includes 1) MVCT - KVCT density difference histogram, 2) MVCT vs KVCT density spectrum, 3) multiple average profile density comparison and 4) density difference in homogeneous locations. Over two months, the imaging beam stability was compromised several times due to a combination of target wobbling, spectral calibration, target change and magnetron issues. The stability of the image values were analyzed over the same period. Results show that the impact on the patient dose calculation is 0.7% +− 0.6%.« less

MO-B-BRB-00: Three Dimensional Dosimetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Full three-dimensional (3D) dosimetry using volumetric chemical dosimeters probed by 3D imaging systems has long been a promising technique for the radiation therapy clinic, since it provides a unique methodology for dose measurements in the volume irradiated using complex conformal delivery techniques such as IMRT and VMAT. To date true 3D dosimetry is still not widely practiced in the community; it has been confined to centres of specialized expertise especially for quality assurance or commissioning roles where other dosimetry techniques are difficult to implement. The potential for improved clinical applicability has been advanced considerably in the last decade by themore » development of improved 3D dosimeters (e.g., radiochromic plastics, radiochromic gel dosimeters and normoxic polymer gel systems) and by improved readout protocols using optical computed tomography or magnetic resonance imaging. In this session, established users of some current 3D chemical dosimeters will briefly review the current status of 3D dosimetry, describe several dosimeters and their appropriate imaging for dose readout, present workflow procedures required for good dosimetry, and analyze some limitations for applications in select settings. We will review the application of 3D dosimetry to various clinical situations describing how 3D approaches can complement other dose delivery validation approaches already available in the clinic. The applications presented will be selected to inform attendees of the unique features provided by full 3D techniques. Learning Objectives: L. John Schreiner: Background and Motivation Understand recent developments enabling clinically practical 3D dosimetry, Appreciate 3D dosimetry workflow and dosimetry procedures, and Observe select examples from the clinic. Sofie Ceberg: Application to dynamic radiotherapy Observe full dosimetry under dynamic radiotherapy during respiratory motion, and Understand how the measurement of high resolution dose data in an irradiated volume can help understand interplay effects during TomoTherapy or VMAT. Titania Juang: Special techniques in the clinic and research Understand the potential for 3D dosimetry in validating dose accumulation in deformable systems, and Observe the benefits of high resolution measurements for precision therapy in SRS and in MicroSBRT for small animal irradiators Geoffrey S. Ibbott: 3D Dosimetry in end-to-end dosimetry QA Understand the potential for 3D dosimetry for end-to-end radiation therapy process validation in the in-house and external credentialing setting. Canadian Institutes of Health Research; L. Schreiner, Modus QA, London, ON, Canada; T. Juang, NIH R01CA100835.« less

MO-B-BRB-04: 3D Dosimetry in End-To-End Dosimetry QA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ibbott, G.

Full three-dimensional (3D) dosimetry using volumetric chemical dosimeters probed by 3D imaging systems has long been a promising technique for the radiation therapy clinic, since it provides a unique methodology for dose measurements in the volume irradiated using complex conformal delivery techniques such as IMRT and VMAT. To date true 3D dosimetry is still not widely practiced in the community; it has been confined to centres of specialized expertise especially for quality assurance or commissioning roles where other dosimetry techniques are difficult to implement. The potential for improved clinical applicability has been advanced considerably in the last decade by themore » development of improved 3D dosimeters (e.g., radiochromic plastics, radiochromic gel dosimeters and normoxic polymer gel systems) and by improved readout protocols using optical computed tomography or magnetic resonance imaging. In this session, established users of some current 3D chemical dosimeters will briefly review the current status of 3D dosimetry, describe several dosimeters and their appropriate imaging for dose readout, present workflow procedures required for good dosimetry, and analyze some limitations for applications in select settings. We will review the application of 3D dosimetry to various clinical situations describing how 3D approaches can complement other dose delivery validation approaches already available in the clinic. The applications presented will be selected to inform attendees of the unique features provided by full 3D techniques. Learning Objectives: L. John Schreiner: Background and Motivation Understand recent developments enabling clinically practical 3D dosimetry, Appreciate 3D dosimetry workflow and dosimetry procedures, and Observe select examples from the clinic. Sofie Ceberg: Application to dynamic radiotherapy Observe full dosimetry under dynamic radiotherapy during respiratory motion, and Understand how the measurement of high resolution dose data in an irradiated volume can help understand interplay effects during TomoTherapy or VMAT. Titania Juang: Special techniques in the clinic and research Understand the potential for 3D dosimetry in validating dose accumulation in deformable systems, and Observe the benefits of high resolution measurements for precision therapy in SRS and in MicroSBRT for small animal irradiators Geoffrey S. Ibbott: 3D Dosimetry in end-to-end dosimetry QA Understand the potential for 3D dosimetry for end-to-end radiation therapy process validation in the in-house and external credentialing setting. Canadian Institutes of Health Research; L. Schreiner, Modus QA, London, ON, Canada; T. Juang, NIH R01CA100835.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, R; Liu, T; Qi, S

Purposes: There has been growing interest in treating breast cancer using VMAT technique. Our goal is to compare the dosimetry and treatment delivery parameters for the left-sided breast cancer treatment using various VMAT platforms from commercially available planning systems. Methods: Five consecutive left-sided breast cancer patients initially treated with conventional 3D-conformal radiotherapy (3DCRT) were selected. Four VMAT plans using most popular treatment planning systems, including Eclipse (Version 11, Varian), Pinnacle (Version 9.8, Philips), Monaco (Version 2.03, Elekta) and helical Tomotherapy (V4.0, Accuray). The same structure set and same planning goals were used for all VMAT plans. The dosimetric parameters includingmore » target coverage and minimum/maximum/mean, dose-volume endpoints for the selected normal structures: the heart, ipsilateral-/contralateral lung and breast, were evaluated. Other dosimetric indices including heterogeneity index (HI) were evaluated. The treatment delivery parameters, such as monitor unit (MUs) and delivery time were also compared. Results: VMAT increases dose homogeneity to the treated volume and reduces the irradiated heart and left-lung volumes. Compared to the 3DCRT technique, all VMAT plans offer better heart and left-lung dose sparing; the mean heart doses were 4.5±1.6(Monaco), 1.2±0.4(Pinnacle), 1.3± (Eclipse) and 5.6±4.4(Tomo), the mean left-lung doses were 5.9±1.5(Monaco), 3.7±0.7(Pinnacle), 1.4± (Eclipse) and 5.2±1.6 (Tomo), while for the 3DCRT plan, the mean heart and left-Lung doses were 2.9±2.0, and 6.8±4.4 (Gy) respectively. The averaged contralateral-breast and lung mean doses were higher in VMAT plans than the 3DCRT plans but were not statistically significant. Among all the VMAT plans, the Pinnacle plans often yield the lowest right-lung/breast mean doses, and slightly better heterogeneity indices that are similar to Tomotherapy plans. Treatment delivery time of the VMAT plans (except helical Tomotherapy IMRT) is estimated to be comparable with the conventional 3DCRT. Conclusion: VMAT achieves equal or better PTV coverage and comparable OARs sparing compared to the conventional 3DCRT techniques.« less

Measurements to predict the time of target replacement of a helical tomotherapy.

PubMed

Kampfer, Severin; Schell, Stefan; Duma, Marciana N; Wilkens, Jan J; Kneschaurek, Peter

2011-11-15

Intensity-modulated radiation therapy (IMRT) requires more beam-on time than normal open field treatment. Consequently, the machines wear out and need more spare parts. A helical tomotherapy treatment unit needs a periodical tungsten target replacement, which is a time consuming event. To be able to predict the next replacement would be quite valuable. We observed unexpected variations towards the end of the target lifetime in the performed pretreatment measurements for patient plan verification. Thus, we retrospectively analyze the measurements of our quality assurance program. The time dependence of the quotient of two simultaneous dose measurements at different depths within a phantom for a fixed open field irradiation is evaluated. We also assess the time-dependent changes of an IMRT plan measurement and of a relative depth dose curve measurement. Additionally, we performed a Monte Carlo simulation with Geant4 to understand the physical reasons for the measured values. Our measurements show that the dose at a specified depth compared to the dose in shallower regions of the phantom declines towards the end of the target lifetime. This reproducible effect can be due to the lowering of the mean energy of the X-ray spectrum. These results are supported by the measurements of the IMRT plan, as well as the study of the relative depth dose curve. Furthermore, the simulation is consistent with these findings since it provides a possible explanation for the reduction of the mean energy for thinner targets. It could be due to the lowering of low energy photon self-absorption in a worn out and therefore thinner target. We state a threshold value for our measurement at which a target replacement should be initiated. Measurements to observe a change in the energy are good predictors of the need for a target replacement. However, since all results support the softening of the spectrum hypothesis, all depth-dependent setups are viable for analyzing the deterioration of the tungsten target. The suggested measurements and criteria to replace the target can be very helpful for every user of a TomoTherapy machine.

Patient positioning in head and neck cancer : Setup variations and safety margins in helical tomotherapy.

PubMed

Leitzen, Christina; Wilhelm-Buchstab, Timo; Müdder, Thomas; Heimann, Martina; Koch, David; Schmeel, Christopher; Simon, Birgit; Stumpf, Sabina; Vornholt, Susanne; Garbe, Stephan; Röhner, Fred; Schoroth, Felix; Schild, Hans Heinz; Schüller, Heinrich

2018-05-01

To evaluate the interfractional variations of patient positioning during intensity-modulated radiotherapy (IMRT) with helical tomotherapy in head and neck cancer and to calculate the required safety margins (sm) for bony landmarks resulting from the necessary table adjustments. In all, 15 patients with head and neck cancer were irradiated using the Hi-Art II tomotherapy system between April and September 2016. Before therapy sessions, patient position was frequently checked by megavolt computed tomography (MV-CT). Necessary table adjustments (ta) in the right-left (rl), superior-inferior (si) and anterior-posterior (ap) directions were recorded for four anatomical points: second, fourth and sixth cervical vertebral body (CVB), anterior nasal spine (ANS). Based upon these data sm were calculated for non-image-guided radiotherapy, image-guided radiotherapy (IGRT) and image guidance limited to a shortened area (CVB 2). Based upon planning CT the actual treatment required ta from -0.05 ± 1.31 mm for CVB 2 (ap) up to 2.63 ± 2.39 mm for ANS (rl). Considering the performed ta resulting from image control (MV-CT) we detected remaining ta from -0.10 ± 1.09 mm for CVB 4 (rl) up to 1.97 ± 1.64 mm for ANS (si). After theoretical adjustment of patients position to CVB 2 the resulting ta ranged from -0.11 ± 2.44 mm for CVB6 (ap) to 2.37 ± 2.17 mm for ANS (si). These data imply safety margins: uncorrected patient position: 3.63-9.95 mm, corrected positioning based upon the whole target volume (IGRT): 1.85-6.63 mm, corrected positioning based upon CVB 2 (IGRT): 3.13-6.66 mm. The calculated safety margins differ between anatomic regions. Repetitive and frequent image control of patient positioning is necessary that, however, possibly may be focussed on a limited region.

Sparing of the Neural Stem Cell Compartment During Whole-Brain Radiation Therapy: A Dosimetric Study Using Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marsh, James C., E-mail: james_marsh@rush.ed; Godbole, Rohit H.; Herskovic, Arnold M.

2010-11-01

Purpose: To assess the feasibility of dosimetrically sparing the hippocampus and neural stem cell (NSC) compartment during whole-brain radiotherapy (WBRT) and prophylactic cranial irradiation (PCI). Methods and Materials: We contoured the brain/brainstem on fused magnetic resonance /computed tomography images as the planning target volume (PTV) in 10 patients, excluding the hippocampus and NSC compartment as organs at risk. PCI and WBRT helical tomotherapy plans were prepared for each patient, with 1.0-cm field width, a pitch of 0.285, and a modulation factor of 2.5. We attempted to maximally spare the hippocampus and NSC compartment while treating the rest of the brainmore » to 30 Gy in 15 fractions (PCI) or 35 Gy in 14 fractions (WBRT) with a V{sub 100} of {>=}95%. Plan quality was assessed by calculating mean dose, equivalent uniform dose (EUD), and biologically equivalent dose (BED) for organs at risk and the percent volume of the PTV receiving the prescribed dose of V{sub 100}. Results: In the PCI plans, mean doses/EUD/BED for the hippocampus and NSC compartment were 11.5 Gy/13.1 Gy/15.7 Gy{sub 2} (BED assuming alpha/beta ratio of 2Gy) and 11.5 Gy/13.1 Gy/12.3 Gy{sub 10} (BED assuming alpha/beta ratio of 10Gy), respectively. In the WBRT plans, mean doses/EUD/BED for the hippocampus and NSC compartment were 11.8 Gy/14.8 Gy/16.8 Gy{sub 2} and 11.8 Gy/14.8 Gy/12.8 Gy{sub 10}, respectively. The mean V{sub 95} for the rest of the brain (PTV) was 96.9% for both the PCI and WBRT plans. Mean PCI and WBRT treatment times were 15.93 min (range, 14.28 min-17.50 min) and 20.18 min (range, 18.43 min-22.32 min), respectively. Conclusions: It is dosimetrically feasible to spare the hippocampus and NSC compartment using helical tomotherapy during the administration of whole-brain irradiation.« less

The Impact of the Grid Size on TomoTherapy for Prostate Cancer

PubMed Central

Kawashima, Motohiro; Kawamura, Hidemasa; Onishi, Masahiro; Takakusagi, Yosuke; Okonogi, Noriyuki; Okazaki, Atsushi; Sekihara, Tetsuo; Ando, Yoshitaka; Nakano, Takashi

2017-01-01

Discretization errors due to the digitization of computed tomography images and the calculation grid are a significant issue in radiation therapy. Such errors have been quantitatively reported for a fixed multifield intensity-modulated radiation therapy using traditional linear accelerators. The aim of this study is to quantify the influence of the calculation grid size on the dose distribution in TomoTherapy. This study used ten treatment plans for prostate cancer. The final dose calculation was performed with “fine” (2.73 mm) and “normal” (5.46 mm) grid sizes. The dose distributions were compared from different points of view: the dose-volume histogram (DVH) parameters for planning target volume (PTV) and organ at risk (OAR), the various indices, and dose differences. The DVH parameters were used Dmax, D2%, D2cc, Dmean, D95%, D98%, and Dmin for PTV and Dmax, D2%, and D2cc for OARs. The various indices used were homogeneity index and equivalent uniform dose for plan evaluation. Almost all of DVH parameters for the “fine” calculations tended to be higher than those for the “normal” calculations. The largest difference of DVH parameters for PTV was Dmax and that for OARs was rectal D2cc. The mean difference of Dmax was 3.5%, and the rectal D2cc was increased up to 6% at the maximum and 2.9% on average. The mean difference of D95% for PTV was the smallest among the differences of the other DVH parameters. For each index, whether there was a significant difference between the two grid sizes was determined through a paired t-test. There were significant differences for most of the indices. The dose difference between the “fine” and “normal” calculations was evaluated. Some points around high-dose regions had differences exceeding 5% of the prescription dose. The influence of the calculation grid size in TomoTherapy is smaller than traditional linear accelerators. However, there was a significant difference. We recommend calculating the final dose using the “fine” grid size. PMID:28974860

Distance-to-Agreement Investigation of Tomotherapy's Bony Anatomy-Based Autoregistration and Planning Target Volume Contour-Based Optimization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suh, Steve, E-mail: ssuh@coh.org; Schultheiss, Timothy E.

Purpose: To compare Tomotherapy's megavoltage computed tomography bony anatomy autoregistration with the best achievable registration, assuming no deformation and perfect knowledge of planning target volume (PTV) location. Methods and Materials: Distance-to-agreement (DTA) of the PTV was determined by applying a rigid-body shift to the PTV region of interest of the prostate from its reference position, assuming no deformations. Planning target volume region of interest of the prostate was extracted from the patient archives. The reference position was set by the 6 degrees of freedom (dof)—x, y, z, roll, pitch, and yaw—optimization results from the previous study at this institution. Themore » DTA and the compensating parameters were calculated by the shift of the PTV from the reference 6-dof to the 4-dof—x, y, z, and roll—optimization. In this study, the effectiveness of Tomotherapy's 4-dof bony anatomy–based autoregistration was compared with the idealized 4-dof PTV contour-based optimization. Results: The maximum DTA (maxDTA) of the bony anatomy-based autoregistration was 3.2 ± 1.9 mm, with the maximum value of 8.0 mm. The maxDTA of the contour-based optimization was 1.8 ± 1.3 mm, with the maximum value of 5.7 mm. Comparison of Pearson correlation of the compensating parameters between the 2 4-dof optimization algorithms shows that there is a small but statistically significant correlation in y and z (0.236 and 0.300, respectively), whereas there is very weak correlation in x and roll (0.062 and 0.025, respectively). Conclusions: We find that there is an average improvement of approximately 1 mm in terms of maxDTA on the PTV going from 4-dof bony anatomy-based autoregistration to the 4-dof contour-based optimization. Pearson correlation analysis of the 2 4-dof optimizations suggests that uncertainties due to deformation and inadequate resolution account for much of the compensating parameters, but pitch variation also makes a statistically significant contribution.« less

Helical Tomotherapy With Simultaneous Integrated Boost After Laparoscopic Staging in Patients With Cervical Cancer: Analysis of Feasibility and Early Toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marnitz, Simone, E-mail: simone.marnitz@charite.de; Koehler, Christhardt; Burova, Elena

Purpose: To demonstrate the feasibility and safety of the simultaneous integrated boost technique for dose escalation in combination with helical tomotherapy in patients with cervical cancer. Methods and Materials: Forty patients (International Federation of Gynecology and Obstetrics Stage IB1 pN1-IVA) underwent primary chemoradiation with helical tomotherapy. Before therapy, 29/40 patients underwent laparoscopic pelvic and para-aortic lymphadenectomy. In 21%, 31%, and 3% of the patients, pelvic, pelvic and para-aortic, and skip metastases in the para-aortic region could be confirmed. All patients underwent radiation with 1.8-50.4 Gy to the tumor region and the pelvic (para-aortic) lymph node region (planning target volume-A), andmore » a simultaneous boost with 2.12-59.36 Gy to the boost region (planning target volume-B). The boost region was defined using titan clips during laparoscopic staging. In all other patients, standardized borders for the planning target volume-B were defined. High-dose-rate brachytherapy was performed in 39/40 patients. The mean biologic effective dose to the macroscopic tumor ranged from 87.5 to 97.5 Gy. Chemotherapy consisted of weekly cisplatin 40 mg/m{sup 2}. Dose-volume histograms and acute gastrointestinal, genitourinary, and hematologic toxicity were evaluated. Results: The mean treatment time was 45 days. The mean doses to the small bowel, rectum, and bladder were 28.5 {+-} 6.1 Gy, 47.9 {+-} 3.8 Gy, and 48 {+-} 3 Gy, respectively. Hematologic toxicity Grade 3 occurred in 20% of patients, diarrhea Grade 2 in 5%, and diarrhea Grade 3 in 2.5%. There was no Grade 3 genitourinary toxicity. All patients underwent curettage 3 months after chemoradiation, which confirmed complete pathologic response in 38/40 patients. Conclusions: The concept of simultaneous integrated boost for dose escalation in patients with cervical cancer is feasible, with a low rate of acute gastrointestinal and genitourinary toxicity. Whether dose escalation can be translated into improved outcome will be assessed after a longer follow-up time.« less

Geometric validation of MV topograms for patient localization on TomoTherapy

NASA Astrophysics Data System (ADS)

Blanco Kiely, Janid P.; White, Benjamin M.; Low, Daniel A.; Qi, Sharon X.

2016-01-01

Our goal was to geometrically validate the use of mega-voltage orthogonal scout images (MV topograms) as a fast and low-dose alternative to mega-voltage computed tomography (MVCT) for daily patient localization on the TomoTherapy system. To achieve this, anthropomorphic head and pelvis phantoms were imaged on a 16-slice kilo-voltage computed tomography (kVCT) scanner to synthesize kilo-voltage digitally reconstructed topograms (kV-DRT) in the Tomotherapy detector geometry. MV topograms were generated for couch speeds of 1-4 cm s-1 in 1 cm s-1 increments with static gantry angles in the anterior-posterior and left-lateral directions. Phantoms were rigidly translated in the anterior-posterior (AP), superior-inferior (SI), and lateral (LAT) directions to simulate potential setup errors. Image quality improvement was demonstrated by estimating the noise level in the unenhanced and enhanced MV topograms using a principle component analysis-based noise level estimation algorithm. Average noise levels for the head phantom were reduced by 2.53 HU (AP) and 0.18 HU (LAT). The pelvis phantom exhibited average noise level reduction of 1.98 HU (AP) and 0.48 HU (LAT). Mattes Mutual Information rigid registration was used to register enhanced MV topograms with corresponding kV-DRT. Registration results were compared to the known rigid displacements, which assessed the MV topogram localization’s sensitivity to daily positioning errors. Reduced noise levels in the MV topograms enhanced the registration results so that registration errors were  <1 mm. The unenhanced head MV topograms had discrepancies  <2.1 mm and the pelvis topograms had discrepancies  <2.7 mm. Result were found to be consistent regardless of couch speed. In total, 64.7% of the head phantom MV topograms and 60.0% of the pelvis phantom MV topograms exactly measured the phantom offsets. These consistencies demonstrated the potential for daily patient positioning using MV topogram pairs in the context bony-anatomy based procedures such as total marrow irradiation, total body irradiation, and cranial spinal irradiation.

MO-D-213-04: The Proximity to the Skin of PTV Affects PTV Coverage and Skin Dose for TomoTherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reynolds, T; Higgins, P; Watanabe, Y

Purpose: The proximity to the skin surface of the PTV for the patients with skin disease could be a concern in terms of the PTV coverage and actual surface dose (SD). IMRT optimization algorithms increase the beam intensity close to the skin in order to compensate for lack of scattering material, leading to enhanced SD but potential hot spots. This study aims to investigate the effect of PTV proximity to the skin on planning and measured SD Methods: All measurements were done for 6 MV X-ray beam of Helical TomoTherapy. An anthropomorphic phantom was scanned in a CT simulator inmore » a routine manner with thermoplastic mask immobilization. PTVs were created with varying distances to the skin of 0 mm -(PTV1), 1 mm- (PTV2), 2 mm-(PTV3) and 3 mm-(PTV4). Also, a 5 mm bolus was used with PTV1 (PTV5). All planning constraints were kept the same in all studies (hard constraint: 95% of the prescription dose covered 95% of the PTV). Gafchromic film (EBT3) was placed under the mask on the phantom surface, and the resulting dose was estimated using RIT software. Results: Optimizing the dose using different PTVs lead to average planned target doses of 10.8, 10.3, 10.2, 10.3 and 10.0 Gy, with maximum doses 12.2, 11.2, 11.1, 11.1 and 10.0 Gy for PTV1, PTV2, PTV3, PTV4 and PTV5, respectively. EBT3 measurements indicated a significant decrease of SD with skin distance by 12.7% (PTV1), 21.9% (PTV2), 24.8% (PTV3) and 28.4% (PTV4) comparing to prescription dose. Placement of a 5 mm bolus on the phantom surface resulted in a SD close to prescribed (+0.5%). Conclusion: This work provides a clear demonstration of the relationship between the skin dose and the PTV to the skin distance. The results indicate the necessity of a bolus even for TomoTherapy when high skin dose is required.« less

Accelerated partial breast irradiation using robotic radiotherapy: a dosimetric comparison with tomotherapy and three-dimensional conformal radiotherapy.

PubMed

Rault, Erwann; Lacornerie, Thomas; Dang, Hong-Phuong; Crop, Frederik; Lartigau, Eric; Reynaert, Nick; Pasquier, David

2016-02-27

Accelerated partial breast irradiation (APBI) is a new breast treatment modality aiming to reduce treatment time using hypo fractionation. Compared to conventional whole breast irradiation that takes 5 to 6 weeks, APBI is reported to induce worse cosmetic outcomes both when using three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT). These late normal tissue effects may be attributed to the dose volume effect because a large portion of the non-target breast tissue volume (NTBTV) receives a high dose. In the context of APBI, non-coplanar beams could spare the NTBTV more efficiently. This study evaluates the dosimetric benefit of using the Cyberknife (CK) for APBI in comparison to IMRT (Tomotherapy) and three dimensional conformal radiotherapy (3D-CRT). The possibility of using surgical clips, implanted during surgery, to track target movements is investigated first. A phantom of a female thorax was designed in-house using the measurements of 20 patients. Surgical clips of different sizes were inserted inside the breast. A treatment plan was delivered to the mobile and immobile phantom. The motion compensation accuracy was evaluated using three radiochromic films inserted inside the breast. Three dimensional conformal radiotherapy (3D-CRT), Tomotherapy (TOMO) and CK treatment plans were calculated for 10 consecutive patients who received APBI in Lille. To ensure a fair comparison of the three techniques, margins applied to the CTV were set to 10 mm. However, a second CK plan was prepared using 3 mm margins to evaluate the benefits of motion compensation. Only the larger clips (VITALITEC Medium-Large) could be tracked inside the larger breast (all gamma indices below 1 for 1 % of the maximum dose and 1 mm). All techniques meet the guidelines defined in the NSABP/RTOG and SHARE protocols. As the applied dose volume constraints are very strong, insignificant dosimetric differences exist between techniques regarding the PTV coverage and the sparing of the lung and heart. However, the CK may be used to reduce high doses received by the NTBTV more efficiently. Robotic stereotactic radiotherapy may be used for APBI to more efficiently spare the NTBTV and improve cosmetic results of APBI.

CT Perfusion Imaging as an Early Biomarker of Differential Response to Stereotactic Radiosurgery in C6 Rat Gliomas

PubMed Central

Yeung, Timothy Pok Chi; Kurdi, Maher; Wang, Yong; Al-Khazraji, Baraa; Morrison, Laura; Hoffman, Lisa; Jackson, Dwayne; Crukley, Cathie; Lee, Ting-Yim; Bauman, Glenn; Yartsev, Slav

2014-01-01

Background The therapeutic efficacy of stereotactic radiosurgery for glioblastoma is not well understood, and there needs to be an effective biomarker to identify patients who might benefit from this treatment. This study investigated the efficacy of computed tomography (CT) perfusion imaging as an early imaging biomarker of response to stereotactic radiosurgery in a malignant rat glioma model. Methods Rats with orthotopic C6 glioma tumors received either mock irradiation (controls, N = 8) or stereotactic radiosurgery (N = 25, 12 Gy in one fraction) delivered by Helical Tomotherapy. Twelve irradiated animals were sacrificed four days after stereotactic radiosurgery to assess acute CT perfusion and histological changes, and 13 irradiated animals were used to study survival. Irradiated animals with survival >15 days were designated as responders while those with survival ≤15 days were non-responders. Longitudinal CT perfusion imaging was performed at baseline and regularly for eight weeks post-baseline. Results Early signs of radiation-induced injury were observed on histology. There was an overall survival benefit following stereotactic radiosurgery when compared to the controls (log-rank P<0.04). Responders to stereotactic radiosurgery showed lower relative blood volume (rBV), and permeability-surface area (PS) product on day 7 post-stereotactic radiosurgery when compared to controls and non-responders (P<0.05). rBV and PS on day 7 showed correlations with overall survival (P<0.05), and were predictive of survival with 92% accuracy. Conclusions Response to stereotactic radiosurgery was heterogeneous, and early selection of responders and non-responders was possible using CT perfusion imaging. Validation of CT perfusion indices for response assessment is necessary before clinical implementation. PMID:25329655

Dosimetric impact of daily setup variations during treatment of canine nasal tumors using intensity-modulated radiation therapy.

PubMed

Deveau, Michael A; Gutiérrez, Alonso N; Mackie, Thomas R; Tomé, Wolfgang A; Forrest, Lisa J

2010-01-01

Intensity-modulated radiation therapy (IMRT) can be employed to yield precise dose distributions that tightly conform to targets and reduce high doses to normal structures by generating steep dose gradients. Because of these sharp gradients, daily setup variations may have an adverse effect on clinical outcome such that an adjacent normal structure may be overdosed and/or the target may be underdosed. This study provides a detailed analysis of the impact of daily setup variations on optimized IMRT canine nasal tumor treatment plans when variations are not accounted for due to the lack of image guidance. Setup histories of ten patients with nasal tumors previously treated using helical tomotherapy were replanned retrospectively to study the impact of daily setup variations on IMRT dose distributions. Daily setup shifts were applied to IMRT plans on a fraction-by-fraction basis. Using mattress immobilization and laser alignment, mean setup error magnitude in any single dimension was at least 2.5 mm (0-10.0 mm). With inclusions of all three translational coordinates, mean composite offset vector was 5.9 +/- 3.3 mm. Due to variations, a loss of equivalent uniform dose for target volumes of up to 5.6% was noted which corresponded to a potential loss in tumor control probability of 39.5%. Overdosing of eyes and brain was noted by increases in mean normalized total dose and highest normalized dose given to 2% of the volume. Findings suggest that successful implementation of canine nasal IMRT requires daily image guidance to ensure accurate delivery of precise IMRT distributions when non-rigid immobilization techniques are utilized. Unrecognized geographical misses may result in tumor recurrence and/or radiation toxicities to the eyes and brain.

DOSIMETRIC IMPACT OF DAILY SETUP VARIATIONS DURING TREATMENT OF CANINE NASAL TUMORS USING INTENSITY-MODULATED RADIATION THERAPY

PubMed Central

Deveau, Michael A.; Gutiérrez, Alonso N.; Mackie, Thomas R.; Tomé, Wolfgang A.; Forrest, Lisa J.

2009-01-01

Intensity-modulated radiation therapy (IMRT) can be employed to yield precise dose distributions that tightly conform to targets and reduce high doses to normal structures by generating steep dose gradients. Because of these sharp gradients, daily setup variations may have an adverse effect on clinical outcome such that an adjacent normal structure may be overdosed and/or the target may be underdosed. This study provides a detailed analysis of the impact of daily setup variations on optimized IMRT canine nasal tumor treatment plans when variations are not accounted for due to the lack of image guidance. Setup histories of ten patients with nasal tumors previously treated using helical tomotherapy were replanned retrospectively to study the impact of daily setup variations on IMRT dose distributions. Daily setup shifts were applied to IMRT plans on a fraction-by-fraction basis. Using mattress immobilization and laser alignment, mean setup error magnitude in any single dimension was at least 2.5mm (0-10.0mm). With inclusions of all three translational coordinates, mean composite offset vector was 5.9±3.3mm. Due to variations, a loss of equivalent uniform dose (EUD) for target volumes of up to 5.6% was noted which corresponded to a potential loss in TCP of 39.5%. Overdosing of eyes and brain was noted by increases in mean normalized total dose (NTDmean) and highest normalized dose given to 2% of the volume (NTD2%). Findings suggest that successful implementation of canine nasal IMRT requires daily image guidance to ensure accurate delivery of precise IMRT distributions when non-rigid immobilization techniques are utilized. Unrecognized geographical misses may result in tumor recurrence and/or radiation toxicities to the eyes and brain. PMID:20166402

Autophagy Therapeutic Potential of Garlic in Human Cancer Therapy

PubMed Central

Chu, Yung-Lin; Raghu, Rajasekaran; Lu, Kuan-Hung; Liu, Chun-Ting; Lin, Shu-Hsi; Lai, Yi-Syuan; Cheng, Wei-Cheng; Lin, Shih-Hang; Sheen, Lee-Yan

2013-01-01

Cancer is one of the deadliest diseases against humans. To tackle this menace, humans have developed several high-technology therapies, such as chemotherapy, tomotherapy, targeted therapy, and antibody therapy. However, all these therapies have their own adverse side effects. Therefore, recent years have seen increased attention being given to the natural food for complementary therapy, which have less side effects. Garlic (Dà Suàn; Allium sativum), is one of most powerful food used in many of the civilizations for both culinary and medicinal purpose. In general, these foods induce cancer cell death by apoptosis, autophagy, or necrosis. Studies have discussed how natural food factors regulate cell survival or death by autophagy in cancer cells. From many literature reviews, garlic could not only induce apoptosis but also autophagy in cancer cells. Autophagy, which is called type-II programmed cell death, provides new strategy in cancer therapy. In conclusion, we wish that garlic could be the pioneer food of complementary therapy in clinical cancer treatment and increase the life quality of cancer patients. PMID:24716172

Autophagy therapeutic potential of garlic in human cancer therapy.

PubMed

Chu, Yung-Lin; Raghu, Rajasekaran; Lu, Kuan-Hung; Liu, Chun-Ting; Lin, Shu-Hsi; Lai, Yi-Syuan; Cheng, Wei-Cheng; Lin, Shih-Hang; Sheen, Lee-Yan

2013-07-01

Cancer is one of the deadliest diseases against humans. To tackle this menace, humans have developed several high-technology therapies, such as chemotherapy, tomotherapy, targeted therapy, and antibody therapy. However, all these therapies have their own adverse side effects. Therefore, recent years have seen increased attention being given to the natural food for complementary therapy, which have less side effects. Garlic (Dà Suàn; Allium sativum), is one of most powerful food used in many of the civilizations for both culinary and medicinal purpose. In general, these foods induce cancer cell death by apoptosis, autophagy, or necrosis. Studies have discussed how natural food factors regulate cell survival or death by autophagy in cancer cells. From many literature reviews, garlic could not only induce apoptosis but also autophagy in cancer cells. Autophagy, which is called type-II programmed cell death, provides new strategy in cancer therapy. In conclusion, we wish that garlic could be the pioneer food of complementary therapy in clinical cancer treatment and increase the life quality of cancer patients.

Implant breast reconstruction followed by radiotherapy: Can helical tomotherapy become a standard irradiation treatment?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Massabeau, Carole, E-mail: cmassabeau@hotmail.com; Fournier-Bidoz, Nathalie; Wakil, Georges

2012-01-01

To evaluate the benefits and limitations of helical tomotherapy (HT) for loco-regional irradiation of patients after a mastectomy and immediate implant-based reconstruction. Ten breast cancer patients with retropectoral implants were randomly selected for this comparative study. Planning target volumes (PTVs) 1 (the volume between the skin and the implant, plus margin) and 2 (supraclavicular, infraclavicular, and internal mammary nodes, plus margin) were 50 Gy in 25 fractions using a standard technique and HT. The extracted dosimetric data were compared using a 2-tailed Wilcoxon matched-pair signed-rank test. Doses for PTV1 and PTV2 were significantly higher with HT (V95 of 98.91 andmore » 97.91%, respectively) compared with the standard technique (77.46 and 72.91%, respectively). Similarly, the indexes of homogeneity were significantly greater with HT (p = 0.002). HT reduced ipsilateral lung volume that received {>=}20 Gy (16.7 vs. 35%), and bilateral lungs (p = 0.01) and neighboring organs received doses that remained well below tolerance levels. The heart volume, which received 25 Gy, was negligible with both techniques. HT can achieve full target coverage while decreasing high doses to the heart and ipsilateral lung. However, the low doses to normal tissue volumes need to be reduced in future studies.« less

Dosimetric effect on pediatric conformal treatment plans using dynamic jaw with Tomotherapy HDA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han, Eun Young, E-mail: eyhan@uams.edu; Kim, Dong-Wook; Zhang, Xin

It is important to minimize the radiation dose delivered to healthy tissues in pediatric cancer treatment because of the risk of secondary malignancies. Tomotherapy HDA provides a dynamic jaw (DJ) delivery mode that creates a sharper penumbra at the craniocaudal ends of a target in addition to a fixed jaw (FJ) delivery mode. The purpose of this study was to evaluate its dosimetric effect on the pediatric cancer cases. We included 6 pediatric cases in this study. The dose profiles and plan statistics—target dose conformity, uniformity, organ-at-risk (OAR) mean dose, beam-on time, and integral dose—were compared for each case. Consequently,more » the target dose coverage and uniformity were similar for different jaw settings. The OAR dose sparing depended on its relative location to the target and disease sites. For example, in the head and neck cancer cases, the brain stem dose using DJ 2.5 was reduced by more than two-fold (2.4 Gy vs. 6.3 Gy) than that obtained with FJ 2.5. The integral dose with DJ 2.5 decreased by more than 9% compared with that with FJ 2.5. Thus, using dynamic jaw in pediatric cases could be critical to reduce a probability of a secondary malignancy.« less

Patient- and therapy-related factors associated with the incidence of xerostomia in nasopharyngeal carcinoma patients receiving parotid-sparing helical tomotherapy.

PubMed

Lee, Tsair-Fwu; Liou, Ming-Hsiang; Ting, Hui-Min; Chang, Liyun; Lee, Hsiao-Yi; Wan Leung, Stephen; Huang, Chih-Jen; Chao, Pei-Ju

2015-08-20

We investigated the incidence of moderate to severe patient-reported xerostomia among nasopharyngeal carcinoma (NPC) patients treated with helical tomotherapy (HT) and identified patient- and therapy-related factors associated with acute and chronic xerostomia toxicity. The least absolute shrinkage and selection operator (LASSO) normal tissue complication probability (NTCP) models were developed using quality-of-life questionnaire datasets from 67 patients with NPC. For acute toxicity, the dosimetric factors of the mean doses to the ipsilateral submandibular gland (Dis) and the contralateral submandibular gland (Dcs) were selected as the first two significant predictors. For chronic toxicity, four predictive factors were selected: age, mean dose to the oral cavity (Doc), education, and T stage. The substantial sparing data can be used to avoid xerostomia toxicity. We suggest that the tolerance values corresponded to a 20% incidence of complications (TD20) for Dis = 39.0 Gy, Dcs = 38.4 Gy, and Doc = 32.5 Gy, respectively, when mean doses to the parotid glands met the QUANTEC 25 Gy sparing guidelines. To avoid patient-reported xerostomia toxicity, the mean doses to the parotid gland, submandibular gland, and oral cavity have to meet the sparing tolerance, although there is also a need to take inherent patient characteristics into consideration.

SU-E-J-275: Impact of the Intra and Inter Observer Variability in the Delineation of Parotid Glands On the Dose Calculation During Head and Neck Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jodda, A; Piotrowski, T

2014-06-01

Purpose: The intra- and inter-observer variability in delineation of the parotids on the kilo-voltage computed tomography (kVCT) and mega-voltage computed tomography (MVCT) were examined to establish their impact on the dose calculation during adaptive head and neck helical tomotherapy (HT). Methods: Three observers delineated left and right parotids for ten randomly selected patients with oropharynx cancer treated on HT. The pre-treatment kVCT and the MVCT from the first fraction of irradiation were selected to delineation. The delineation procedure was repeated three times by each observer. The parotids were delineated according to the institutional protocol. The analyses included intra-observer reproducibility andmore » inter-structure, -observer and -modality variability of the volume and dose. Results: The differences between the left and right parotid outlines were not statistically significant (p>0.3). The reproducibility of the delineation was confirmed for each observer on the kVCT (p>0.2) and on the MVCT (p>0.1). The inter-observer variability of the outlines was significant (p<0.001) as well as the inter-modality variability (p<0.006). The parotids delineated on the MVCT were 10% smaller than on the kVCT. The inter-observer variability of the parotids delineation did not affect the average dose (p=0.096 on the kVCT and p=0.176 on the MVCT). The dose calculated on the MVCT was higher by 3.3% than dose from the kVCT (p=0.009). Conclusion: Usage of the institutional protocols for the parotids delineation reduces intra-observer variability and increases reproducibility of the outlines. These protocols do not eliminate delineation differences between the observers, but these differences are not clinically significant and do not affect average doses in the parotids. The volumes of the parotids delineated on the MVCT are smaller than on the kVCT, which affects the differences in the calculated doses.« less

SU-E-T-370: Evaluating Plan Quality and Dose Delivery Accuracy of Tomotherapy SBRT Treatments for Lung Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blake, S; Thwaites, D; Hansen, C

2015-06-15

Purpose: This study evaluated the plan quality and dose delivery accuracy of stereotactic body radiotherapy (SBRT) helical Tomotherapy (HT) treatments for lung cancer. Results were compared with those previously reported by our group for flattening filter (FF) and flattening filter free (FFF) VMAT treatments. This work forms part of an ongoing multicentre and multisystem planning and dosimetry audit on FFF beams for lung SBRT. Methods: CT datasets and DICOM RT structures delineating the target volume and organs at risk for 6 lung cancer patients were selected. Treatment plans were generated using the HT treatment planning system. Tumour locations were classifiedmore » as near rib, near bronchial tree or in free lung with prescribed doses of 48Gy/4fr, 50Gy/5fr and 54Gy/3fr respectively. Dose constraints were specified by a modified RTOG0915 protocol used for an Australian SBRT phase II trial. Plan quality was evaluated using mean PTV dose, PTV volume receiving 100% of the prescribed dose (V100%), target conformity (CI=VD100%/VPTV) and low dose spillage (LDS=VD50%/VPTV). Planned dose distributions were compared to those measured using an ArcCheck phantom. Delivery accuracy was evaluated using a gamma-index pass rate of 95% with 3% (of max dose) and 3mm criteria. Results: Treatment plans for all patients were clinically acceptable in terms of quality and accuracy of dose delivery. The following DVH metrics are reported as averages (SD) of all plans investigated: mean PTV dose was 115.3(2.4)% of prescription, V100% was 98.8(0.9)%, CI was 1.14(0.03) and LDS was 5.02(0.37). The plans had an average gamma-index passing rate of 99.3(1.3)%. Conclusion: The results reported in this study for HT agree within 1 SD to those previously published by our group for VMAT FF and FFF lung SBRT treatments. This suggests that HT delivers lung SBRT treatments of comparable quality and delivery accuracy as VMAT using both FF and FFF beams.« less

SU-E-P-30: Clinical Applications of Spatially Fractionated Radiation Therapy (GRID) Using Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, X; Liang, X; Penagaricano, J

2015-06-15

Purpose: To present the first clinical applications of Helical Tomotherapy-based spatially fractionated radiotherapy (HT-GRID) for deep seated tumors and associated dosimetric study. Methods: Ten previously treated GRID patients were selected (5 HT-GRID and 5 LINAC-GRID using a commercially available GRID block). Each case was re-planned either in HT-GRID or LINAC-GRID for a total of 10 plans for both techniques using same prescribed dose of 20 Gy to maximum point dose of GRID GTV. For TOMO-GRID, a programmable virtual TOMOGRID template mimicking a GRID pattern was generated. Dosimetric parameters compared included: GRID GTV mean dose (Dmean) and equivalent uniform dose (EUD),more » GRID GTV dose inhomogeneity (Ratio(valley/peak)), normal tissue Dmean and EUD, and other organs-at-risk(OARs) doses. Results: The median tumor volume was 634 cc, ranging from 182 to 4646 cc. Median distance from skin to the deepest part of tumor was 22cm, ranging from 8.9 to 38cm. The median GRID GTV Dmean and EUD was 10.65Gy (9.8–12.5Gy) and 7.62Gy (4.31–11.06Gy) for HT-GRID and was 6.73Gy (4.44–8.44Gy) and 3.95Gy (0.14–4.2Gy) for LINAC-GRID. The median Ratio(valley/peak) was 0.144(0.05–0.29) for HT-GRID and was 0.055(0.0001–0.14) for LINAC-GRID. For normal tissue in HT-GRID, the median Dmean and EUD was 1.24Gy (0.34–2.54Gy) and 5.45 Gy(3.45–6.89Gy) and was 0.61 Gy(0.11–1.52Gy) and 6Gy(4.45–6.82Gy) for LINAC-GRID. The OAR doses were comparable between the HT-GRID and LINAC-GRID. However, in some cases it was not possible to avoid a critical structure in LINAC-GRID; while HT-GRID can spare more tissue doses for certain critical structures. Conclusion: HT-GRID delivers higher GRID GTV Dmean, EUD and Ratio(valley/peak) compared to LINAC-GRID. HT-GRID delivers higher Dmean and lower EUD for normal tissue compared to LINAC-GRID. TOMOGRID template can be highly patient-specific and allows adjustment of the GRID pattern to different tumor sizes and shapes when they are deeply-seated and cannot be safely treated with LINAC-GRID.« less

TOPICAL REVIEW: A review of dosimetry studies on external-beam radiation treatment with respect to second cancer induction

NASA Astrophysics Data System (ADS)

Xu, X. George; Bednarz, Bryan; Paganetti, Harald

2008-07-01

It has been long known that patients treated with ionizing radiation carry a risk of developing a second cancer in their lifetimes. Factors contributing to the recently renewed concern about the second cancer include improved cancer survival rate, younger patient population as well as emerging treatment modalities such as intensity-modulated radiation treatment (IMRT) and proton therapy that can potentially elevate secondary exposures to healthy tissues distant from the target volume. In the past 30 years, external-beam treatment technologies have evolved significantly, and a large amount of data exist but appear to be difficult to comprehend and compare. This review article aims to provide readers with an understanding of the principles and methods related to scattered doses in radiation therapy by summarizing a large collection of dosimetry and clinical studies. Basic concepts and terminology are introduced at the beginning. That is followed by a comprehensive review of dosimetry studies for external-beam treatment modalities including classical radiation therapy, 3D-conformal x-ray therapy, intensity-modulated x-ray therapy (IMRT and tomotherapy) and proton therapy. Selected clinical data on second cancer induction among radiotherapy patients are also covered. Problems in past studies and controversial issues are discussed. The needs for future studies are presented at the end.

PET evaluation of late cerebral effect in advanced radiation therapy techniques for cranial base tumors.

PubMed

Alongi, Pierpaolo; Iaccarino, Leonardo; Losa, Marco; Del Vecchio, Antonella; Gerevini, Simonetta; Plebani, Valentina; Di Muzio, Nadia; Mortini, Pietro; Gianolli, Luigi; Perani, Daniela

2018-05-25

Even though the benefits of radiation therapy are well established, it is important to recognize the broad spectrum of radiation-induced changes, particularly in the central nervous system. The possible damage to the brain parenchyma may have clinical consequences and in particular cognitive impairment might be one of the major complication of radiotherapy. To date, no studies have investigated the effects of focal radiation therapy on brain structure and function together with the assessment of their clinical outcomes at a long follow-up. In this prospective study, we evaluated in six patients the possible brain late effects after radiation therapy, using a standardized neuropsychological battery, MRI and 18F-FDG PET using SPM and semi-quantitative methods, in patients affected by cranial base tumors who underwent gamma knife or tomotherapy. Neuropsychological examinations showed no cognitive impairment after the treatment. In all patients, both MRI assessment and 18F-FDG-PET did not reveal any local or distant anatomical and metabolic late effects. The present study support the safety of advanced radiation therapy techniques. 18F-FDG-PET, using SPM and semi-quantitative methods, might be a valuable tool to evaluate the cerebral radiotoxicity in patients treated for brain neoplasms. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

SU-F-J-98: Improvement and Evaluation Of Deformation Image Registration On Parotid Glands During Radiation Therapy for Nasopharyngeal Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, S; PLA General Hospital, Beijing; Wu, Z

2016-06-15

Purpose: To quantitatively evaluate the strategic innovation and accuracy variation of deformation registration algorithm for parotid glands using the similarity Dice coefficient during the course of radiation therapy (RT) for nasopharyngeal cancer (NPC). Methods: Daily MVCT data for 10 patients with pathologically proven nasopharyngeal cancers were analyzed. The data were acquired using tomotherapy (TomoTherapy, Accuray) at the PLA General Hospital. The prescription dose to the primary target was 70Gy in 33 fractions. Two kinds of contours for parotid glands on daily MVCTs were obtained by populating these contours from planning CTs to the daily CTs via rigid-body registration with ormore » without the rotation shifts using the in-house tools and the Adaptive plan software (Adaptive Plan, TomoTherapy), and were edited manually if necessary. The diffeomorphic Demons algorithm developed in the in-house tool was used to propagate the parotid structures from the daily CTs to planning CTs. The differences of the mapped parotid contours in two methods were evaluated using Dice similarity index (DSI). Two-tailed t-test analysis was carried out to compare the DSI changes during the course of RT. Results: For 10 patient plans, the accuracy of deformation image registration (DIR) with the rotation shift was obviously better than those without the rotation shift. The Dice scores of the ipsi- and contra-lateral parotids for with and without the rotation shifts were found to be correlated with each other [0.904±0.031 vs 0.919±0.030 (p<0.001); 0.900±0.031 vs 0.910±0.032 (p<0.001)]. The Dice scores for the parotids have shown the reduction with the changes of parotid volumes during RT. The DSI values between the first and last fraction were 0.932±0.020 vs 0.899±0.030 in 10 patient plans. Conclusion: DIR was successfully improved using the strategic innovation for ART. And the decrease of DIR accuracy has also been found during the delivery of fractionated radiotherapy. This work was supported in part by the grant from Chinese Natural Science Foundation (Grant No. 11105225).« less

SU-E-J-109: Evaluation of Deformable Accumulated Parotid Doses Using Different Registration Algorithms in Adaptive Head and Neck Radiotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, S; Chinese PLA General Hospital, Beijing, 100853 China; Liu, B

2015-06-15

Purpose: Three deformable image registration (DIR) algorithms are utilized to perform deformable dose accumulation for head and neck tomotherapy treatment, and the differences of the accumulated doses are evaluated. Methods: Daily MVCT data for 10 patients with pathologically proven nasopharyngeal cancers were analyzed. The data were acquired using tomotherapy (TomoTherapy, Accuray) at the PLA General Hospital. The prescription dose to the primary target was 70Gy in 33 fractions.Three DIR methods (B-spline, Diffeomorphic Demons and MIMvista) were used to propagate parotid structures from planning CTs to the daily CTs and accumulate fractionated dose on the planning CTs. The mean accumulated dosesmore » of parotids were quantitatively compared and the uncertainties of the propagated parotid contours were evaluated using Dice similarity index (DSI). Results: The planned mean dose of the ipsilateral parotids (32.42±3.13Gy) was slightly higher than those of the contralateral parotids (31.38±3.19Gy)in 10 patients. The difference between the accumulated mean doses of the ipsilateral parotids in the B-spline, Demons and MIMvista deformation algorithms (36.40±5.78Gy, 34.08±6.72Gy and 33.72±2.63Gy ) were statistically significant (B-spline vs Demons, P<0.0001, B-spline vs MIMvista, p =0.002). And The difference between those of the contralateral parotids in the B-spline, Demons and MIMvista deformation algorithms (34.08±4.82Gy, 32.42±4.80Gy and 33.92±4.65Gy ) were also significant (B-spline vs Demons, p =0.009, B-spline vs MIMvista, p =0.074). For the DSI analysis, the scores of B-spline, Demons and MIMvista DIRs were 0.90, 0.89 and 0.76. Conclusion: Shrinkage of parotid volumes results in the dose increase to the parotid glands in adaptive head and neck radiotherapy. The accumulated doses of parotids show significant difference using the different DIR algorithms between kVCT and MVCT. Therefore, the volume-based criterion (i.e. DSI) as a quantitative evaluation of registration accuracy is essential besides the visual assessment by the treating physician. This work was supported in part by the grant from Chinese Natural Science Foundation (Grant No. 11105225)« less

Static beam tomotherapy as an optimisation method in whole-breast radiation therapy (WBRT).

PubMed

Squires, Matthew; Hu, Yunfei; Byrne, Mikel; Archibald-Heeren, Ben; Cheers, Sonja; Bosco, Bruno; Teh, Amy; Fong, Andrew

2017-12-01

TomoTherapy (Accuray, Sunnyvale, CA) has recently introduced a static form of tomotherapy: TomoDirect™ (TD). This study aimed to evaluate TD against a contemporary intensity modulated radiation therapy (IMRT) alternative through comparison of target and organ at risk (OAR) doses in breast cancer cases. A secondary objective was to evaluate planning efficiency by measuring optimisation times. Treatment plans of 27 whole-breast radiation therapy (WBRT) patients optimised with a tangential hybrid IMRT technique were replanned using TD. Parameters included a dynamic field width of 2.5 cm, a pitch of 0.251 and a modulation factor of 2.000; 50 Gy in 25 fractions was prescribed and planning time recorded. The planning metrics used in analysis were ICRU based, with the mean PTV minimum (D 99 ) used as the point of comparison. Both modalities met ICRU50 target heterogeneity objectives (TD D 99 = 48.0 Gy vs. IMRT = 48.1 Gy, P = 0.26; TD D 1 = 53.5 Gy vs. IMRT = 53.0 Gy, P = 0.02; Homogeneity index TD = 0.11 vs. IMRT = 0.10, P = 0.03), with TD plans generating higher median doses (TD D 50 = 51.1 Gy vs. IMRT = 50.9 Gy, P = 0.03). No significant difference was found in prescription dose coverage (TD V 50 = 85.5% vs. IMRT = 82.0%, P = 0.09). TD plans produced a statistically significant reduction in V 5 ipsilateral lung doses (TD V 5 = 23.2% vs. IMRT = 27.2%, P = 0.04), while other queried OARs remained comparable (TD ipsilateral lung V 20 = 13.2% vs. IMRT = 14.6%, P = 0.30; TD heart V 5 = 2.7% vs. IMRT = 2.8%, P = 0.47; TD heart V 10 = 1.7% vs. IMRT = 1.8%, P = 0.44). TD reduced planning time considerably (TD = 9.8 m vs. IMRT = 27.6 m, P < 0.01), saving an average planning time of 17.8 min per patient. TD represents a suitable WBRT treatment approach both in terms of plan quality metrics and planning efficiency. © 2017 The Authors. Journal of Medical Radiation Sciences published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Medical Imaging and Radiation Therapy and New Zealand Institute of Medical Radiation Technology.

Megavoltage computed tomography image guidance with helical tomotherapy in patients with vertebral tumors: analysis of factors influencing interobserver variability.

PubMed

Levegrün, Sabine; Pöttgen, Christoph; Jawad, Jehad Abu; Berkovic, Katharina; Hepp, Rodrigo; Stuschke, Martin

2013-02-01

To evaluate megavoltage computed tomography (MVCT)-based image guidance with helical tomotherapy in patients with vertebral tumors by analyzing factors influencing interobserver variability, considered as quality criterion of image guidance. Five radiation oncologists retrospectively registered 103 MVCTs in 10 patients to planning kilovoltage CTs by rigid transformations in 4 df. Interobserver variabilities were quantified using the standard deviations (SDs) of the distributions of the correction vector components about the observers' fraction mean. To assess intraobserver variabilities, registrations were repeated after ≥4 weeks. Residual deviations after setup correction due to uncorrectable rotational errors and elastic deformations were determined at 3 craniocaudal target positions. To differentiate observer-related variations in minimizing these residual deviations across the 3-dimensional MVCT from image resolution effects, 2-dimensional registrations were performed in 30 single transverse and sagittal MVCT slices. Axial and longitudinal MVCT image resolutions were quantified. For comparison, image resolution of kilovoltage cone-beam CTs (CBCTs) and interobserver variability in registrations of 43 CBCTs were determined. Axial MVCT image resolution is 3.9 lp/cm. Longitudinal MVCT resolution amounts to 6.3 mm, assessed as full-width at half-maximum of thin objects in MVCTs with finest pitch. Longitudinal CBCT resolution is better (full-width at half-maximum, 2.5 mm for CBCTs with 1-mm slices). In MVCT registrations, interobserver variability in the craniocaudal direction (SD 1.23 mm) is significantly larger than in the lateral and ventrodorsal directions (SD 0.84 and 0.91 mm, respectively) and significantly larger compared with CBCT alignments (SD 1.04 mm). Intraobserver variabilities are significantly smaller than corresponding interobserver variabilities (variance ratio [VR] 1.8-3.1). Compared with 3-dimensional registrations, 2-dimensional registrations have significantly smaller interobserver variability in the lateral and ventrodorsal directions (VR 3.8 and 2.8, respectively) but not in the craniocaudal direction (VR 0.75). Tomotherapy image guidance precision is affected by image resolution and residual deviations after setup correction. Eliminating the effect of residual deviations yields small interobserver variabilities with submillimeter precision in the axial plane. In contrast, interobserver variability in the craniocaudal direction is dominated by the poorer longitudinal MVCT image resolution. Residual deviations after image guidance exist and need to be considered when dose gradients ultimately achievable with image guided radiation therapy techniques are analyzed. Copyright © 2013 Elsevier Inc. All rights reserved.

Comparing conformal, arc radiotherapy and helical tomotherapy in craniospinal irradiation planning.

PubMed

Myers, Pamela A; Mavroidis, Panayiotis; Papanikolaou, Nikos; Stathakis, Sotirios

2014-09-08

Currently, radiotherapy treatment plan acceptance is based primarily on dosimetric performance measures. However, use of radiobiological analysis to assess benefit in terms of tumor control and harm in terms of injury to normal tissues can be advantageous. For pediatric craniospinal axis irradiation (CSI) patients, in particular, knowing the technique that will optimize the probabilities of benefit versus injury can lead to better long-term outcomes. Twenty-four CSI pediatric patients (median age 10) were retrospectively planned with three techniques: three-dimensional conformal radiation therapy (3D CRT), volumetric-modulated arc therapy (VMAT), and helical tomotherapy (HT). VMAT plans consisted of one superior and one inferior full arc, and tomotherapy plans were created using a 5.02cm field width and helical pitch of 0.287. Each plan was normalized to 95% of target volume (whole brain and spinal cord) receiving prescription dose 23.4Gy in 13 fractions. Using an in-house MATLAB code and DVH data from each plan, the three techniques were evaluated based on biologically effective uniform dose (D=), the complication-free tumor control probability (P+), and the width of the therapeutically beneficial range. Overall, 3D CRT and VMAT plans had similar values of D= (24.1 and 24.2 Gy), while HT had a D= slightly lower (23.6 Gy). The average values of the P+ index were 64.6, 67.4, and 56.6% for 3D CRT, VMAT, and HT plans, respectively, with the VMAT plans having a statistically significant increase in P+. Optimal values of D= were 28.4, 33.0, and 31.9 Gy for 3D CRT, VMAT, and HT plans, respectively. Although P+ values that correspond to the initial dose prescription were lower for HT, after optimizing the D= prescription level, the optimal P+ became 94.1, 99.5, and 99.6% for 3D CRT, VMAT, and HT, respectively, with the VMAT and HT plans having statistically significant increases in P+. If the optimal dose level is prescribed using a radiobiological evaluation method, as opposed to a purely dosimetric one, the two IMRT techniques, VMAT and HT, will yield largest overall benefit to CSI patients by maximizing tumor control and limiting normal tissue injury. Using VMAT or HT may provide these pediatric patients with better long-term outcomes after radiotherapy.

Should helical tomotherapy replace brachytherapy for cervical cancer? Case report.

PubMed

Hsieh, Chen-Hsi; Wei, Ming-Chow; Hsu, Yao-Peng; Chong, Ngot-Swan; Chen, Yu-Jen; Hsiao, Sheng-Mou; Hsieh, Yen-Ping; Wang, Li-Ying; Shueng, Pei-Wei

2010-11-23

Stereotactic body radiation therapy (SBRT) administered via a helical tomotherapy (HT) system is an effective modality for treating lung cancer and metastatic liver tumors. Whether SBRT delivered via HT is a feasible alternative to brachytherapy in treatment of locally advanced cervical cancer in patients with unusual anatomic configurations of the uterus has never been studied. A 46-year-old woman presented with an 8-month history of abnormal vaginal bleeding. Biopsy revealed squamous cell carcinoma of the cervix. Magnetic resonance imaging (MRI) showed a cervical tumor with direct invasion of the right parametrium, bilateral hydronephrosis, and multiple uterine myomas. International Federation of Gynecology and Obstetrics (FIGO) stage IIIB cervical cancer was diagnosed. Concurrent chemoradiation therapy (CCRT) followed by SBRT delivered via HT was administered instead of brachytherapy because of the presence of multiple uterine myomas with bleeding tendency. Total abdominal hysterectomy was performed after 6 weeks of treatment because of the presence of multiple uterine myomas. Neither pelvic MRI nor results of histopathologic examination at X-month follow-up showed evidence of tumor recurrence. Only grade 1 nausea and vomiting during treatment were noted. Lower gastrointestinal bleeding was noted at 14-month follow-up. No fistula formation and no evidence of haematological, gastrointestinal or genitourinary toxicities were noted on the most recent follow-up. CCRT followed by SBRT appears to be an effective and safe modality for treatment of cervical cancer. Larger-scale studies are warranted.

Dosimetric evaluation of a Monte Carlo IMRT treatment planning system incorporating the MIMiC

NASA Astrophysics Data System (ADS)

Rassiah-Szegedi, P.; Fuss, M.; Sheikh-Bagheri, D.; Szegedi, M.; Stathakis, S.; Lancaster, J.; Papanikolaou, N.; Salter, B.

2007-12-01

The high dose per fraction delivered to lung lesions in stereotactic body radiation therapy (SBRT) demands high dose calculation and delivery accuracy. The inhomogeneous density in the thoracic region along with the small fields used typically in intensity-modulated radiation therapy (IMRT) treatments poses a challenge in the accuracy of dose calculation. In this study we dosimetrically evaluated a pre-release version of a Monte Carlo planning system (PEREGRINE 1.6b, NOMOS Corp., Cranberry Township, PA), which incorporates the modeling of serial tomotherapy IMRT treatments with the binary multileaf intensity modulating collimator (MIMiC). The aim of this study is to show the validation process of PEREGRINE 1.6b since it was used as a benchmark to investigate the accuracy of doses calculated by a finite size pencil beam (FSPB) algorithm for lung lesions treated on the SBRT dose regime via serial tomotherapy in our previous study. Doses calculated by PEREGRINE were compared against measurements in homogeneous and inhomogeneous materials carried out on a Varian 600C with a 6 MV photon beam. Phantom studies simulating various sized lesions were also carried out to explain some of the large dose discrepancies seen in the dose calculations with small lesions. Doses calculated by PEREGRINE agreed to within 2% in water and up to 3% for measurements in an inhomogeneous phantom containing lung, bone and unit density tissue.

Dosimetric effect on pediatric conformal treatment plans using dynamic jaw with Tomotherapy HDA.

PubMed

Han, Eun Young; Kim, Dong-Wook; Zhang, Xin; Penagaricano, Jose; Liang, Xiaoying; Hardee, Matthew; Morrill, Steve; Ratanatharathorn, Vaneerat

2015-01-01

It is important to minimize the radiation dose delivered to healthy tissues in pediatric cancer treatment because of the risk of secondary malignancies. Tomotherapy HDA provides a dynamic jaw (DJ) delivery mode that creates a sharper penumbra at the craniocaudal ends of a target in addition to a fixed jaw (FJ) delivery mode. The purpose of this study was to evaluate its dosimetric effect on the pediatric cancer cases. We included 6 pediatric cases in this study. The dose profiles and plan statistics—target dose conformity, uniformity, organ-at-risk (OAR) mean dose, beam-on time, and integral dose—were compared for each case. Consequently, the target dose coverage and uniformity were similar for different jaw settings. The OAR dose sparing depended on its relative location to the target and disease sites. For example, in the head and neck cancer cases, the brain stem dose using DJ 2.5 was reduced by more than two-fold (2.4 Gy vs. 6.3 Gy) than that obtained with FJ 2.5. The integral dose with DJ 2.5 decreased by more than 9% compared with that with FJ 2.5. Thus, using dynamic jaw in pediatric cases could be critical to reduce a probability of a secondary malignancy. Copyright © 2015 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

Patient- and therapy-related factors associated with the incidence of xerostomia in nasopharyngeal carcinoma patients receiving parotid-sparing helical tomotherapy

PubMed Central

Lee, Tsair-Fwu; Liou, Ming-Hsiang; Ting, Hui-Min; Chang, Liyun; Lee, Hsiao-Yi; Wan Leung, Stephen; Huang, Chih-Jen; Chao, Pei-Ju

2015-01-01

We investigated the incidence of moderate to severe patient-reported xerostomia among nasopharyngeal carcinoma (NPC) patients treated with helical tomotherapy (HT) and identified patient- and therapy-related factors associated with acute and chronic xerostomia toxicity. The least absolute shrinkage and selection operator (LASSO) normal tissue complication probability (NTCP) models were developed using quality-of-life questionnaire datasets from 67 patients with NPC. For acute toxicity, the dosimetric factors of the mean doses to the ipsilateral submandibular gland (Dis) and the contralateral submandibular gland (Dcs) were selected as the first two significant predictors. For chronic toxicity, four predictive factors were selected: age, mean dose to the oral cavity (Doc), education, and T stage. The substantial sparing data can be used to avoid xerostomia toxicity. We suggest that the tolerance values corresponded to a 20% incidence of complications (TD20) for Dis = 39.0 Gy, Dcs = 38.4 Gy, and Doc = 32.5 Gy, respectively, when mean doses to the parotid glands met the QUANTEC 25 Gy sparing guidelines. To avoid patient-reported xerostomia toxicity, the mean doses to the parotid gland, submandibular gland, and oral cavity have to meet the sparing tolerance, although there is also a need to take inherent patient characteristics into consideration. PMID:26289304

Comparison study of the partial-breast irradiation techniques: Dosimetric analysis of three-dimensional conformal radiation therapy, electron beam therapy, and helical tomotherapy depending on various tumor locations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Min-Joo; Park, So-Hyun; Research Institute of Biomedical Engineering, The Catholic University of Korea, Seoul

2013-10-01

The partial-breast irradiation (PBI) technique, an alternative to whole-breast irradiation, is a beam delivery method that uses a limited range of treatment volume. The present study was designed to determine the optimal PBI treatment modalities for 8 different tumor locations. Treatment planning was performed on computed tomography (CT) data sets of 6 patients who had received lumpectomy treatments. Tumor locations were classified into 8 subsections according to breast quadrant and depth. Three-dimensional conformal radiation therapy (3D-CRT), electron beam therapy (ET), and helical tomotherapy (H-TOMO) were utilized to evaluate the dosimetric effect for each tumor location. Conformation number (CN), radical dosemore » homogeneity index (rDHI), and dose delivered to healthy tissue were estimated. The Kruskal-Wallis, Mann-Whitney U, and Bonferroni tests were used for statistical analysis. The ET approach showed good sparing effects and acceptable target coverage for the lower inner quadrant—superficial (LIQ-S) and lower inner quadrant—deep (LIQ-D) locations. The H-TOMO method was the least effective technique as no evaluation index achieved superiority for all tumor locations except CN. The ET method is advisable for treating LIQ-S and LIQ-D tumors, as opposed to 3D-CRT or H-TOMO, because of acceptable target coverage and much lower dose applied to surrounding tissue.« less

MO-F-16A-01: Implementation of MPPG TPS Verification Tests On Various Accelerators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smilowitz, J; Bredfeldt, J; Geurts, M

2014-06-15

Purpose: To demonstrate the implementation of the Medical Physics Practice Guideline (MPPG) for dose calculation and beam parameters verification of treatment planning systems (TPS). Methods: We implemented the draft TPS MPPG for three linacs: Varian Trilogy, TomoHDA and Elekta Infinity. Static and modulated test plans were created. The static fields are different than used in commissioning. Data was collected using ion chambers and diodes in a scanning water tank, Delta4 phantom and a custom phantom. MatLab and Microsoft Excel were used to create analysis tools to compare reference DICOM dose with scan data. This custom code allowed for the interpolation,more » registration and gamma analysis of arbitrary dose profiles. It will be provided as open source code. IMRT fields were validated with Delta4 registration and comparison tools. The time for each task was recorded. Results: The tests confirmed the strengths, and revealed some limitations, of our TPS. The agreement between calculated and measured dose was reported for all beams. For static fields, percent depth dose and profiles were analyzed with criteria in the draft MPPG. The results reveal areas of slight mismatch with the model (MLC leaf penumbra, buildup region.) For TomoTherapy, the IMRT plan 2%/2 mm gamma analysis revealed poorest agreement in the low dose regions. For one static test plan for all 10MV Trilogy photon beams, the plan generation, scan queue creation, data collection, data analysis and report took 2 hours, excluding tank setup. Conclusions: We have demonstrated the implementation feasibility of the TPS MPPG. This exercise generated an open source tool for dose comparisons between scan data and DICOM dose data. An easily reproducible and efficient infrastructure with streamlined data collection was created for repeatable robust testing of the TPS. The tests revealed minor discrepancies in our models and areas for improvement that are being investigated.« less

Marvin: an anatomical phantom for dosimetric evaluation of complex radiotherapy of the head and neck.

PubMed

Aitkenhead, A H; Rowbottom, C G; Mackay, R I

2013-10-07

We report on the design of Marvin, a Model Anatomy for Radiotherapy Verification and audit In the head and Neck and present results demonstrating its use in the development of the Elekta volumetric modulated arc therapy (VMAT) technique at the Christie, and in the audit of TomoTherapy and Varian RapidArc at other institutions. The geometry of Marvin was generated from CT datasets of eight male and female patients lying in the treatment position, with removable inhomogeneities modelling the sinuses and mandible. A modular system allows the phantom to be used with a range of detectors, with the locations of the modules being based on an analysis of a range of typical treatment plans (27 in total) which were mapped onto the phantom geometry. Results demonstrate the use of Gafchromic EBT2/EBT3 film for measurement of relative dose in a plane through the target and organs-at-risk, and the use of a small-volume ionization chamber for measurement of absolute dose in the target and spinal cord. Measurements made during the development of the head and neck VMAT protocol at the Christie quantified the improvement in plan delivery resulting from the installation of the Elekta Integrity upgrade (which permits an effectively continuously variable dose rate), with plans delivered before and after the upgrade having 88.5 ± 9.4% and 98.0 ± 2.2% respectively of points passing a gamma analysis (at 4%, 4 mm, global). Audits of TomoTherapy and Varian RapidArc neck techniques at other institutions showed a similar quality of plan delivery as for post-Integrity Elekta VMAT: film measurements for both techniques had >99% of points passing a gamma analysis at the clinical criteria of 4%, 4 mm, global, and >95% of points passing at tighter criteria of 3%, 3 mm, global; and absolute dose measurements in the PTV and spinal cord were within 1.5% and 3.5% of the planned doses respectively for both techniques. The results demonstrate that Marvin is an efficient and effective means of assessing the quality of delivery of complex radiotherapy in the head and neck, and is a useful tool to assist development and audit of these techniques.

Marvin: an anatomical phantom for dosimetric evaluation of complex radiotherapy of the head and neck

NASA Astrophysics Data System (ADS)

Aitkenhead, A. H.; Rowbottom, C. G.; Mackay, R. I.

2013-10-01

We report on the design of Marvin, a Model Anatomy for Radiotherapy Verification and audit In the head and Neck and present results demonstrating its use in the development of the Elekta volumetric modulated arc therapy (VMAT) technique at the Christie, and in the audit of TomoTherapy and Varian RapidArc at other institutions. The geometry of Marvin was generated from CT datasets of eight male and female patients lying in the treatment position, with removable inhomogeneities modelling the sinuses and mandible. A modular system allows the phantom to be used with a range of detectors, with the locations of the modules being based on an analysis of a range of typical treatment plans (27 in total) which were mapped onto the phantom geometry. Results demonstrate the use of Gafchromic EBT2/EBT3 film for measurement of relative dose in a plane through the target and organs-at-risk, and the use of a small-volume ionization chamber for measurement of absolute dose in the target and spinal cord. Measurements made during the development of the head and neck VMAT protocol at the Christie quantified the improvement in plan delivery resulting from the installation of the Elekta Integrity upgrade (which permits an effectively continuously variable dose rate), with plans delivered before and after the upgrade having 88.5 ± 9.4% and 98.0 ± 2.2% respectively of points passing a gamma analysis (at 4%, 4 mm, global). Audits of TomoTherapy and Varian RapidArc neck techniques at other institutions showed a similar quality of plan delivery as for post-Integrity Elekta VMAT: film measurements for both techniques had >99% of points passing a gamma analysis at the clinical criteria of 4%, 4 mm, global, and >95% of points passing at tighter criteria of 3%, 3 mm, global; and absolute dose measurements in the PTV and spinal cord were within 1.5% and 3.5% of the planned doses respectively for both techniques. The results demonstrate that Marvin is an efficient and effective means of assessing the quality of delivery of complex radiotherapy in the head and neck, and is a useful tool to assist development and audit of these techniques.

Statistical process control and verifying positional accuracy of a cobra motion couch using step-wedge quality assurance tool.

PubMed

Binny, Diana; Lancaster, Craig M; Trapp, Jamie V; Crowe, Scott B

2017-09-01

This study utilizes process control techniques to identify action limits for TomoTherapy couch positioning quality assurance tests. A test was introduced to monitor accuracy of the applied couch offset detection in the TomoTherapy Hi-Art treatment system using the TQA "Step-Wedge Helical" module and MVCT detector. Individual X-charts, process capability (cp), probability (P), and acceptability (cpk) indices were used to monitor a 4-year couch IEC offset data to detect systematic and random errors in the couch positional accuracy for different action levels. Process capability tests were also performed on the retrospective data to define tolerances based on user-specified levels. A second study was carried out whereby physical couch offsets were applied using the TQA module and the MVCT detector was used to detect the observed variations. Random and systematic variations were observed for the SPC-based upper and lower control limits, and investigations were carried out to maintain the ongoing stability of the process for a 4-year and a three-monthly period. Local trend analysis showed mean variations up to ±0.5 mm in the three-monthly analysis period for all IEC offset measurements. Variations were also observed in the detected versus applied offsets using the MVCT detector in the second study largely in the vertical direction, and actions were taken to remediate this error. Based on the results, it was recommended that imaging shifts in each coordinate direction be only applied after assessing the machine for applied versus detected test results using the step helical module. User-specified tolerance levels of at least ±2 mm were recommended for a test frequency of once every 3 months to improve couch positional accuracy. SPC enables detection of systematic variations prior to reaching machine tolerance levels. Couch encoding system recalibrations reduced variations to user-specified levels and a monitoring period of 3 months using SPC facilitated in detecting systematic and random variations. SPC analysis for couch positional accuracy enabled greater control in the identification of errors, thereby increasing confidence levels in daily treatment setups. © 2017 Royal Brisbane and Women's Hospital, Metro North Hospital and Health Service. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Metastatic brain cancer: prediction of response to whole-brain helical tomotherapy with simultaneous intralesional boost for metastatic disease using quantitative MR imaging features

NASA Astrophysics Data System (ADS)

Sharma, Harish; Bauman, Glenn; Rodrigues, George; Bartha, Robert; Ward, Aaron

2014-03-01

The sequential application of whole brain radiotherapy (WBRT) and more targeted stereotactic radiosurgery (SRS) is frequently used to treat metastatic brain tumors. However, SRS has side effects related to necrosis and edema, and requires separate and relatively invasive localization procedures. Helical tomotherapy (HT) allows for a SRS-type simultaneous infield boost (SIB) of multiple brain metastases, synchronously with WBRT and without separate stereotactic procedures. However, some patients' tumors may not respond to HT+SIB, and would be more appropriately treated with radiosurgery or conventional surgery despite the additional risks and side effects. As a first step toward a broader objective of developing a means for response prediction to HT+SIB, the goal of this study was to investigate whether quantitative measurements of tumor size and appearance (including first- and second-order texture features) on a magnetic resonance imaging (MRI) scan acquired prior to treatment could be used to differentiate responder and nonresponder patient groups after HT+SIB treatment of metastatic disease of the brain. Our results demonstrated that smaller lesions may respond better to this form of therapy; measures of appearance provided limited added value over measures of size for response prediction. With further validation on a larger data set, this approach may lead to a means for prediction of individual patient response based on pre-treatment MRI, supporting appropriate therapy selection for patients with metastatic brain cancer.

[Position-checking by imaging embarked there tomotherapy and the delegation to the radiology technician].

PubMed

Autret, A; Choupeaux, D; Le Mée, M

2016-10-01

Tomotherapy is a technique of IMRT and IGRT using a linear accelerator and a helical CT-scanner. To reach this targeting of precision, the repositioning of the patient is essential. The use of a contention adapted according to the location of the disease and the morphology of the patient is necessary for the safety of this one and the treatment. Once the patient positioned on the reference table, technicians of imager's team check by the acquisition of helical imagery with the reference CT-scanner the position of the patient, the zone of the PTV and healthy organs in the protected surroundings. At first, adjustment will be made automatically on three planes of the space (axial, sagittal, frontal) and three rotations (pitch, roll and yaw) by the device of treatment, then the technicians of imagery will bring a modification of these recalls manually. After validation, the processing will then be made in complete safety for the patient and the nursing. This check by MVCT is daily before every session of processing. It is made by the technicians of imagery. The radiation oncologist confirms the images at j0, then controls once a week MVCT. Traceability in the file of the patient of the various marks (osseous and\\or soft tissue) necessary for the daily gaps will be noted by this one to delegate to the technicians of imagery the validation of the MVCT before every session. Copyright © 2016. Published by Elsevier SAS.

Adaptive Radiotherapy Planning on Decreasing Gross Tumor Volumes as Seen on Megavoltage Computed Tomography Images

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woodford, Curtis; Yartsev, Slav; Dar, A. Rashid

2007-11-15

Purpose: To evaluate gross tumor volume (GTV) changes for patients with non-small-cell lung cancer by using daily megavoltage (MV) computed tomography (CT) studies acquired before each treatment fraction on helical tomotherapy and to relate the potential benefit of adaptive image-guided radiotherapy to changes in GTV. Methods and Materials: Seventeen patients were prescribed 30 fractions of radiotherapy on helical tomotherapy for non-small-cell lung cancer at London Regional Cancer Program from Dec 2005 to March 2007. The GTV was contoured on the daily MVCT studies of each patient. Adapted plans were created using merged MVCT-kilovoltage CT image sets to investigate the advantagesmore » of replanning for patients with differing GTV regression characteristics. Results: Average GTV change observed over 30 fractions was -38%, ranging from -12 to -87%. No significant correlation was observed between GTV change and patient's physical or tumor features. Patterns of GTV changes in the 17 patients could be divided broadly into three groups with distinctive potential for benefit from adaptive planning. Conclusions: Changes in GTV are difficult to predict quantitatively based on patient or tumor characteristics. If changes occur, there are points in time during the treatment course when it may be appropriate to adapt the plan to improve sparing of normal tissues. If GTV decreases by greater than 30% at any point in the first 20 fractions of treatment, adaptive planning is appropriate to further improve the therapeutic ratio.« less

Estimation of the risk of secondary malignancy arising from whole-breast irradiation: comparison of five radiotherapy modalities, including TomoHDA.

PubMed

Han, Eun Young; Paudel, Nava; Sung, Jiwon; Yoon, Myonggeun; Chung, Weon Kuu; Kim, Dong Wook

2016-04-19

The risk of secondary cancer from radiation treatment remains a concern for long-term breast cancer survivors, especially those treated with radiation at the age younger than 45 years. Treatment modalities optimally maximize the dose delivery to the tumor while minimizing radiation doses to neighboring organs, which can lead to secondary cancers. A new TomoTherapy treatment machine, TomoHDATM, can treat an entire breast with two static but intensity-modulated beams in a slice-by-slice fashion. This feature could reduce scattered and leakage radiation doses. We compared the plan quality and lifetime attributable risk (LAR) of a second malignancy among five treatment modalities: three-dimensional conformal radiation therapy, field-in-field forward-planned intensity-modulated radiation therapy, inverse-planned intensity-modulated radiation therapy (IMRT), volumetric modulated arc therapy, and TomoDirect mode on the TomoHDA system. Ten breast cancer patients were selected for retrospective analysis. Organ equivalent doses, plan characteristics, and LARs were compared. Out-of-field organ doses were measured with radio-photoluminescence glass dosimeters. Although the IMRT plan provided overall better plan quality, including the lowest probability of pneumonitis, it caused the second highest LAR. The TomoTherapy plan provided plan quality comparable to the IMRT plan and posed the lowest total LAR to neighboring organs. Therefore, it can be a better treatment modality for younger patients who have a longer life expectancy.

Dose responses in a normoxic polymethacrylic acid gel dosimeter using optimal CT scanning parameters

NASA Astrophysics Data System (ADS)

Cho, K. H.; Cho, S. J.; Lee, S.; Lee, S. H.; Min, C. K.; Kim, Y. H.; Moon, S. K.; Kim, E. S.; Chang, A. R.; Kwon, S. I.

2012-05-01

The dosimetric characteristics of normoxic polymethacrylic acid gels are investigated using optimal CT scanning parameters and the possibility of their clinical application is also considered. The effects of CT scanning parameters (tube voltage, tube current, scan time, slick thickness, field of view, and reconstruction algorithm) are experimentally investigated to determine the optimal parameters for minimizing the amount of noise in images obtained using normoxic polymethacrylic acid gel. In addition, the dose sensitivity, dose response, accuracy, and reproducibility of the normoxic polymethacrylic acid gel are evaluated. CT images are obtained using a head phantom that is fabricated for clinical applications. In addition, IMRT treatment planning is performed using a Tomotherapy radiation treatment planning system. A program for analyzing the results is produced using Visual C. A comparison between the treatment planning and the CT images of irradiated gels is performed. The dose sensitivity is found to be 2.41±0.04 HGy-1. The accuracies of dose evaluation at doses of 2 Gy and 4 Gy are 3.0% and 2.6%, respectively, and their reproducibilities are 2.0% and 2.1%, respectively. In the comparison of gel and Tomotherpay planning, the pass rate of the γ-index, based on the reference values of a dose error of 3% and a DTA of 3 mm, is 93.7%.

A novel supine isocentric approach for craniospinal irradiation and its clinical outcome.

PubMed

Cheng, Yi-Kan; Zeng, Lei; Ye, Shu-Biao; Zheng, Jian; Zhang, Lin; Sun, Peng; Jiang, Xiao-Bo; Sun, Wen-Zhao; Xu, Tao; Chen, Lei

2016-09-01

To report a novel approach for craniospinal irradiation (CSI) using a supine isocentric technique. Patients were treated in the supine position using CT simulation. Half-beam-blocked lateral cranial fields and superior spinal fields have the same isocentre, and their beam divergences match. Tangential irradiation provides a non-divergent junction for the other two full-beam spinal fields. Shielding for cranial fields was generated, and dose distribution was calculated using a three-dimensional planning system. When sacral spinal fields were required, two lateral opposite fields were designed to protect the urogenital organs. All treatment portals were filmed once per week. At a median follow-up of 49.8 months, 5 relapses and no cases of radiation myelitis developed in 26 consecutive patients. In the junctions of the brain-spine or spine-spine field, no failure occurred. Three failures occurred in the primary site alone, two in the spinal axis alone. The results of our study have shown that our novel approach for CSI was not associated with increased failures at the field junction and deaths. In addition, no radiation myelitis, pneumonia, severe damage to the heart and gastrointestinal tract, and second cancers occurred in our study. This new approach is an optimal alternative in cancer centre without tomotherapy because of its convenience for immobilization, repeatability, optimal dose distribution and satisfactory clinical outcome.

SU-C-BRB-01: Automated Dose Deformation for Re-Irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lim, S; Kainz, K; Li, X

Purpose: An objective of retreatment planning is to minimize dose to previously irradiated tissues. Conventional retreatment planning is based largely on best-guess superposition of the previous treatment’s isodose lines. In this study, we report a rigorous, automated retreatment planning process to minimize dose to previously irradiated organs at risk (OAR). Methods: Data for representative patients previously treated using helical tomotherapy and later retreated in the vicinity of the original disease site were retrospectively analyzed in an automated fashion using a prototype treatment planning system equipped with a retreatment planning module (Accuray, Inc.). The initial plan’s CT, structures, and planned dosemore » were input along with the retreatment CT and structure set. Using a deformable registration algorithm implemented in the module, the initially planned dose and structures were warped onto the retreatment CT. An integrated third-party sourced software (MIM, Inc.) was used to evaluate registration quality and to contour overlapping regions between isodose lines and OARs, providing additional constraints during retreatment planning. The resulting plan and the conventionally generated retreatment plan were compared. Results: Jacobian maps showed good quality registration between the initial plan and retreatment CTs. For a right orbit case, the dose deformation facilitated delineating the regions of the eyes and optic chiasm originally receiving 13 to 42 Gy. Using these regions as dose constraints, the new retreatment plan resulted in V50 reduction of 28% for the right eye and 8% for the optic chiasm, relative to the conventional plan. Meanwhile, differences in the PTV dose coverage were clinically insignificant. Conclusion: Automated retreatment planning with dose deformation and definition of previously-irradiated regions allowed for additional planning constraints to be defined to minimize re-irradiation of OARs. For serial organs that do not recover from radiation damage, this method provides a more precise and quantitative means to limit cumulative dose. This research is partially supported by Accuray, Inc.« less

TU-F-201-00: Radiochromic Film Dosimetry Update

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Since the introduction of radiochromic films (RCF) for radiation dosimetry, the scope of RCF dosimetry has expanded steadily to include many medical applications, such as radiation therapy and diagnostic radiology. The AAPM Task Group (TG) 55 published a report on the recommendations for RCF dosimetry in 1998. As the technology is advancing rapidly, and its routine clinical use is expanding, TG 235 has been formed to provide an update to TG-55 on radiochromic film dosimetry. RCF dosimetry applications in clinical radiotherapy have become even more widespread, expanding from primarily brachytherapy and radiosurgery applications, and gravitating towards (but not limited to)more » external beam therapy (photon, electron and protons), such as quality assurance for IMRT, VMAT, Tomotherapy, SRS/SRT, and SBRT. In addition, RCF applications now extend to measurements of radiation dose in particle beams and patients undergoing medical exams, especially fluoroscopically guided interventional procedures and CT. The densitometers/scanners used for RCF dosimetry have also evolved from the He-Ne laser scanner to CCD-based scanners, including roller-based scanner, light box-based digital camera, and flatbed color scanner. More recently, multichannel RCF dosimetry introduced a new paradigm for external beam dose QA for its high accuracy and efficiency. This course covers in detail the recent advancements in RCF dosimetry. Learning Objectives: Introduce the paradigm shift on multichannel film dosimetry Outline the procedures to achieve accurate dosimetry with a RCF dosimetry system Provide comprehensive guidelines on RCF dosimetry for various clinical applications One of the speakers has a research agreement from Ashland Inc., the manufacturer of Gafchromic film.« less

TU-F-201-01: General Aspects of Radiochromic Film Dosimetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Niroomand-Rad, A.

Since the introduction of radiochromic films (RCF) for radiation dosimetry, the scope of RCF dosimetry has expanded steadily to include many medical applications, such as radiation therapy and diagnostic radiology. The AAPM Task Group (TG) 55 published a report on the recommendations for RCF dosimetry in 1998. As the technology is advancing rapidly, and its routine clinical use is expanding, TG 235 has been formed to provide an update to TG-55 on radiochromic film dosimetry. RCF dosimetry applications in clinical radiotherapy have become even more widespread, expanding from primarily brachytherapy and radiosurgery applications, and gravitating towards (but not limited to)more » external beam therapy (photon, electron and protons), such as quality assurance for IMRT, VMAT, Tomotherapy, SRS/SRT, and SBRT. In addition, RCF applications now extend to measurements of radiation dose in particle beams and patients undergoing medical exams, especially fluoroscopically guided interventional procedures and CT. The densitometers/scanners used for RCF dosimetry have also evolved from the He-Ne laser scanner to CCD-based scanners, including roller-based scanner, light box-based digital camera, and flatbed color scanner. More recently, multichannel RCF dosimetry introduced a new paradigm for external beam dose QA for its high accuracy and efficiency. This course covers in detail the recent advancements in RCF dosimetry. Learning Objectives: Introduce the paradigm shift on multichannel film dosimetry Outline the procedures to achieve accurate dosimetry with a RCF dosimetry system Provide comprehensive guidelines on RCF dosimetry for various clinical applications One of the speakers has a research agreement from Ashland Inc., the manufacturer of Gafchromic film.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiu-Tsao, S.

Since the introduction of radiochromic films (RCF) for radiation dosimetry, the scope of RCF dosimetry has expanded steadily to include many medical applications, such as radiation therapy and diagnostic radiology. The AAPM Task Group (TG) 55 published a report on the recommendations for RCF dosimetry in 1998. As the technology is advancing rapidly, and its routine clinical use is expanding, TG 235 has been formed to provide an update to TG-55 on radiochromic film dosimetry. RCF dosimetry applications in clinical radiotherapy have become even more widespread, expanding from primarily brachytherapy and radiosurgery applications, and gravitating towards (but not limited to)more » external beam therapy (photon, electron and protons), such as quality assurance for IMRT, VMAT, Tomotherapy, SRS/SRT, and SBRT. In addition, RCF applications now extend to measurements of radiation dose in particle beams and patients undergoing medical exams, especially fluoroscopically guided interventional procedures and CT. The densitometers/scanners used for RCF dosimetry have also evolved from the He-Ne laser scanner to CCD-based scanners, including roller-based scanner, light box-based digital camera, and flatbed color scanner. More recently, multichannel RCF dosimetry introduced a new paradigm for external beam dose QA for its high accuracy and efficiency. This course covers in detail the recent advancements in RCF dosimetry. Learning Objectives: Introduce the paradigm shift on multichannel film dosimetry Outline the procedures to achieve accurate dosimetry with a RCF dosimetry system Provide comprehensive guidelines on RCF dosimetry for various clinical applications One of the speakers has a research agreement from Ashland Inc., the manufacturer of Gafchromic film.« less

Simultaneous infield boost with helical tomotherapy for patients with 1 to 3 brain metastases.

PubMed

Bauman, Glenn; Yartsev, Slav; Fisher, Barb; Kron, Tomas; Laperriere, Normand; Heydarian, Mostafa; VanDyk, Jake

2007-02-01

We sought to model the feasibility of a simultaneous in field boost (SIB) to individual brain metastases during a course of whole brain radiotherapy (WBXRT) using helical tomotherapy (HT) intensity-modulated radiation therapy. Planning computed tomography data from 14 patients with 1 to 3 brain metastases were used to model an intralesional SIB delivery that yielded a total intralesional dose of 60 Gy with a surrounding whole brain dose of 30 Gy (designed to be isoeffective to WBXRT of 30 Gy with an 18 Gy in 1 fraction radiosurgery boost). Accuracy of treatment of a phantom on the HT unit was measured. Comparisons of HT delivery versus a conventional stereotactic radiotherapy technique for a particularly challenging simulated anatomy were made. In all cases, SIB to 60 Gy with WBXRT to 30 Gy was possible while maintaining critical structures below assigned dose limits. Estimated radiation delivery time for the SIB treatment was approximately 10 minutes per fraction. Planning and treatment of the head phantom was associated with an overall accuracy of 2 mm. Comparison to conventional noncoplanar arc fractionated stereotactic radiotherapy plan demonstrated similar target coverage and improved critical tissue sparing even for a challenging anatomy with multiple lesions in the same plane as the optic apparatus. Based on this study, use of an image guided SIB using HT seemed feasible and a phase I trial initiated at our institution is described. Potential advantages of this approach include frameless stereotaxis through daily megavoltage computed tomography localization, more efficient use of resources and exploitation of radiobiologic advantages of fractionation.

Integral radiation dose to normal structures with conformal external beam radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aoyama, Hidefumi; Westerly, David Clark; Mackie, Thomas Rockwell

2006-03-01

Background: This study was designed to evaluate the integral dose (ID) received by normal tissue from intensity-modulated radiotherapy (IMRT) for prostate cancer. Methods and Materials: Twenty-five radiation treatment plans including IMRT using a conventional linac with both 6 MV (6MV-IMRT) and 20 MV (20MV-IMRT), as well as three-dimensional conformal radiotherapy (3DCRT) using 6 MV (6MV-3DCRT) and 20 MV (20MV-3DCRT) and IMRT using tomotherapy (6MV) (Tomo-IMRT), were created for 5 patients with localized prostate cancer. The ID (mean dose x tissue volume) received by normal tissue (NTID) was calculated from dose-volume histograms. Results: The 6MV-IMRT resulted in 5.0% lower NTID thanmore » 6MV-3DCRT; 20 MV beam plans resulted in 7.7%-11.2% lower NTID than 6MV-3DCRT. Tomo-IMRT NTID was comparable to 6MV-IMRT. Compared with 6MV-3DCRT, 6MV-IMRT reduced IDs to the rectal wall and penile bulb by 6.1% and 2.7%, respectively. Tomo-IMRT further reduced these IDs by 11.9% and 16.5%, respectively. The 20 MV did not reduce IDs to those structures. Conclusions: The difference in NTID between 3DCRT and IMRT is small. The 20 MV plans somewhat reduced NTID compared with 6 MV plans. The advantage of tomotherapy over conventional IMRT and 3DCRT for localized prostate cancer was demonstrated in regard to dose sparing of rectal wall and penile bulb while slightly decreasing NTID as compared with 6MV-3DCRT.« less

Real-time in vivo dosimetry with MOSFET detectors in serial tomotherapy for head and neck cancer patients.

PubMed

Qi, Zhen-Yu; Deng, Xiao-Wu; Huang, Shao-Min; Shiu, Almon; Lerch, Michael; Metcalfe, Peter; Rosenfeld, Anatoly; Kron, Tomas

2011-08-01

A real-time dose verification method using a recently designed metal oxide semiconductor field effect transistor (MOSFET) dosimetry system was evaluated for quality assurance (QA) of intensity-modulated radiation therapy (IMRT). Following the investigation of key parameters that might affect the accuracy of MOSFET measurements (i.e., source surface distance [SSD], field size, beam incident angles and radiation energy spectrum), the feasibility of this detector in IMRT dose verification was demonstrated by comparison with ion chamber measurements taken in an IMRT QA phantom. Real-time in vivo measurements were also performed with the MOSFET system during serial tomotherapy treatments administered to 8 head and neck cancer patients. MOSFET sensitivity did not change with SSD. For field sizes smaller than 20 × 20 cm(2), MOFET sensitivity varied within 1.0%. The detector angular response was isotropic within 2% over 360°, and the observed sensitivity variation due to changes in the energy spectrum was negligible in 6-MV photons. MOSFET system measurements and ion chamber measurements agreed at all points in IMRT phantom plan verification, within 5%. The mean difference between 48 IMRT MOSFET-measured doses and calculated values in 8 patients was 3.33% and ranged from -2.20% to 7.89%. More than 90% of the total measurements had deviations of less than 5% from the planned doses. The MOSFET dosimetry system has been proven to be an effective tool in evaluating the actual dose within individual patients during IMRT treatment. Copyright © 2011 Elsevier Inc. All rights reserved.

Technical Note: Relationships between gamma criteria and action levels: Results of a multicenter audit of gamma agreement index results.

PubMed

Crowe, Scott B; Sutherland, Bess; Wilks, Rachael; Seshadri, Venkatakrishnan; Sylvander, Steven; Trapp, Jamie V; Kairn, Tanya

2016-03-01

The aim of this work was to use a multicenter audit of modulated radiotherapy quality assurance (QA) data to provide a practical examination of gamma evaluation criteria and action level selection. The use of the gamma evaluation method for patient-specific pretreatment QA is widespread, with most commercial solutions implementing the method. Gamma agreement indices were calculated using the criteria 1%/1 mm, 2%/2 mm, 2%/3 mm, 3%/2 mm, 3%/3 mm, and 5%/3 mm for 1265 pretreatment QA measurements, planned at seven treatment centers, using four different treatment planning systems, delivered using three different delivery systems (intensity-modulated radiation therapy, volumetric-modulated arc therapy, and helical tomotherapy) and measured using three different dose measurement systems. The sensitivity of each pair of gamma criteria was evaluated relative to the gamma agreement indices calculated using 3%/3 mm. A linear relationship was observed for 2%/2 mm, 2%/3 mm, and 3%/2 mm. This result implies that most beams failing at 3%/3 mm would also fail for those criteria, if the action level was adjusted appropriately. Some borderline plans might be passed or failed depending on the relative priority (tighter tolerance) used for dose difference or distance to agreement evaluation. Dosimeter resolution and treatment modality were found to have a smaller effect on the results of QA measurements than the number of dimensions (2D or 3D) over which the gamma evaluation was calculated. This work provides a method (and a large sample of results) for calculating equivalent action levels for different gamma evaluation criteria. This work constitutes a valuable guide for clinical decision making and a means to compare published gamma evaluation results from studies using different evaluation criteria. More generally, the data provided by this work support the recommendation that gamma criteria that specifically prioritize the property of greatest clinical importance for each treatment modality of anatomical site should be selected when using gamma evaluations for modulated radiotherapy QA. It is therefore suggested that departments using the gamma evaluation as a QA analysis tool should consider the relative importance of dose difference and distance to agreement, when selecting gamma evaluation criteria.

Dosimetric comparison of helical tomotherapy treatment plans for total marrow irradiation created using GPU and CPU dose calculation engines.

PubMed

Nalichowski, Adrian; Burmeister, Jay

2013-07-01

To compare optimization characteristics, plan quality, and treatment delivery efficiency between total marrow irradiation (TMI) plans using the new TomoTherapy graphic processing unit (GPU) based dose engine and CPU/cluster based dose engine. Five TMI plans created on an anthropomorphic phantom were optimized and calculated with both dose engines. The planning treatment volume (PTV) included all the bones from head to mid femur except for upper extremities. Evaluated organs at risk (OAR) consisted of lung, liver, heart, kidneys, and brain. The following treatment parameters were used to generate the TMI plans: field widths of 2.5 and 5 cm, modulation factors of 2 and 2.5, and pitch of either 0.287 or 0.43. The optimization parameters were chosen based on the PTV and OAR priorities and the plans were optimized with a fixed number of iterations. The PTV constraint was selected to ensure that at least 95% of the PTV received the prescription dose. The plans were evaluated based on D80 and D50 (dose to 80% and 50% of the OAR volume, respectively) and hotspot volumes within the PTVs. Gamma indices (Γ) were also used to compare planar dose distributions between the two modalities. The optimization and dose calculation times were compared between the two systems. The treatment delivery times were also evaluated. The results showed very good dosimetric agreement between the GPU and CPU calculated plans for any of the evaluated planning parameters indicating that both systems converge on nearly identical plans. All D80 and D50 parameters varied by less than 3% of the prescription dose with an average difference of 0.8%. A gamma analysis Γ(3%, 3 mm) < 1 of the GPU plan resulted in over 90% of calculated voxels satisfying Γ < 1 criterion as compared to baseline CPU plan. The average number of voxels meeting the Γ < 1 criterion for all the plans was 97%. In terms of dose optimization/calculation efficiency, there was a 20-fold reduction in planning time with the new GPU system. The average optimization/dose calculation time utilizing the traditional CPU/cluster based system was 579 vs 26.8 min for the GPU based system. There was no difference in the calculated treatment delivery time per fraction. Beam-on time varied based on field width and pitch and ranged between 15 and 28 min. The TomoTherapy GPU based dose engine is capable of calculating TMI treatment plans with plan quality nearly identical to plans calculated using the traditional CPU/cluster based system, while significantly reducing the time required for optimization and dose calculation.

Dosimetric Comparison of Helical Tomotherapy and Dynamic Conformal Arc Therapy in Stereotactic Radiosurgery for Vestibular Schwannomas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Tsair-Fwu, E-mail: tflee@cc.kuas.edu.t; Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan; Chao, Pei-Ju

2011-04-01

The dosimetric results of stereotactic radiosurgery (SRS) for vestibular schwannoma (VS) performed using dynamic conformal arc therapy (DCAT) with the Novalis system and helical TomoTherapy (HT) were compared using plan quality indices. The HT plans were created for 10 consecutive patients with VS previously treated with SRS using the Novalis system. The dosimetric indices used to compare the techniques included the conformity index (CI) and homogeneity index (HI) for the planned target volume (PTV), the comprehensive quality index (CQI) for nine organs at risk (OARs), gradient score index (GSI) for the dose drop-off outside the PTV, and plan quality indexmore » (PQI), which was verified using the plan quality discerning power (PQDP) to incorporate 3 plan indices, to evaluate the rival plans. The PTV ranged from 0.27-19.99 cm{sup 3} (median 3.39 cm{sup 3}), with minimum required PTV prescribed doses of 10-16 Gy (median 12 Gy). Both systems satisfied the minimum required PTV prescription doses. HT conformed better to the PTV (CI: 1.51 {+-} 0.23 vs. 1.94 {+-} 0.34; p < 0.01), but had a worse drop-off outside the PTV (GSI: 40.3 {+-} 10.9 vs. 64.9 {+-} 13.6; p < 0.01) compared with DCAT. No significant difference in PTV homogeneity was observed (HI: 1.08 {+-} 0.03 vs. 1.09 {+-} 0.02; p = 0.20). HT had a significantly lower maximum dose in 4 OARs and significant lower mean dose in 1 OAR; by contrast, DCAT had a significantly lower maximum dose in 1 OAR and significant lower mean dose in 2 OARs, with the CQI of the 9 OARs = 0.92 {+-} 0.45. Plan analysis using PQI (HT 0.37 {+-} 0.12 vs. DCAT 0.65 {+-} 0.08; p < 0.01), and verified using the PQDP, confirmed the dosimetric advantage of HT. However, the HT system had a longer beam-on time (33.2 {+-} 7.4 vs. 4.6 {+-} 0.9 min; p < 0.01) and consumed more monitor units (16772 {+-} 3803 vs. 1776 {+-} 356.3; p < 0.01). HT had a better dose conformity and similar dose homogeneity but worse dose gradient than DCAT. Plan analysis confirmed the dosimetric advantage of HT, although not all indices revealed a better outcome for HT. Whether this dosimetric advantage translates into a clinical benefit deserves further investigation.« less

Evaluation of surface and shallow depth dose reductions using a Superflab bolus during conventional and advanced external beam radiotherapy.

PubMed

Yoon, Jihyung; Xie, Yibo; Zhang, Rui

2018-03-01

The purpose of this study was to evaluate a methodology to reduce scatter and leakage radiations to patients' surface and shallow depths during conventional and advanced external beam radiotherapy. Superflab boluses of different thicknesses were placed on top of a stack of solid water phantoms, and the bolus effect on surface and shallow depth doses for both open and intensity-modulated radiotherapy (IMRT) beams was evaluated using thermoluminescent dosimeters and ion chamber measurements. Contralateral breast dose reduction caused by the bolus was evaluated by delivering clinical postmastectomy radiotherapy (PMRT) plans to an anthropomorphic phantom. For the solid water phantom measurements, surface dose reduction caused by the Superflab bolus was achieved only in out-of-field area and on the incident side of the beam, and the dose reduction increased with bolus thickness. The dose reduction caused by the bolus was more significant at closer distances from the beam. Most of the dose reductions occurred in the first 2-cm depth and stopped at 4-cm depth. For clinical PMRT treatment plans, surface dose reductions using a 1-cm Superflab bolus were up to 31% and 62% for volumetric-modulated arc therapy and 4-field IMRT, respectively, but there was no dose reduction for Tomotherapy. A Superflab bolus can be used to reduce surface and shallow depth doses during external beam radiotherapy when it is placed out of the beam and on the incident side of the beam. Although we only validated this dose reduction strategy for PMRT treatments, it is applicable to any external beam radiotherapy and can potentially reduce patients' risk of developing radiation-induced side effects. © 2018 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao, Z; Reyhan, M; Huang, Q

Purpose: The calibration of the Hounsfield units (HU) to relative proton stopping powers (RSP) is a crucial component in assuring the accurate delivery of proton therapy dose distributions to patients. The purpose of this work is to assess the uncertainty of CT calibration considering the impact of CT slice thickness, position of the plug within the phantom and phantom sizes. Methods: Stoichiometric calibration method was employed to develop the CT calibration curve. Gammex 467 tissue characterization phantom was scanned in Tomotherapy Cheese phantom and Gammex 451 phantom by using a GE CT scanner. Each plug was individually inserted into themore » same position of inner and outer ring of phantoms at each time, respectively. 1.25 mm and 2.5 mm slice thickness were used. Other parameters were same. Results: HU of selected human tissues were calculated based on fitted coefficient (Kph, Kcoh and KKN), and RSP were calculated according to the Bethe-Bloch equation. The calibration curve was obtained by fitting cheese phantom data with 1.25 mm thickness. There is no significant difference if the slice thickness, phantom size, position of plug changed in soft tissue. For boney structure, RSP increases up to 1% if the phantom size and the position of plug changed but keep the slice thickness the same. However, if the slice thickness varied from the one in the calibration curve, 0.5%–3% deviation would be expected depending on the plug position. The Inner position shows the obvious deviation (averagely about 2.5%). Conclusion: RSP shows a clinical insignificant deviation in soft tissue region. Special attention may be required when using a different slice thickness from the calibration curve for boney structure. It is clinically practical to address 3% deviation due to different thickness in the definition of clinical margins.« less

Evaluation of the optimal combinations of modulation factor and pitch for Helical TomoTherapy plans made with TomoEdge using Pareto optimal fronts.

PubMed

De Kerf, Geert; Van Gestel, Dirk; Mommaerts, Lobke; Van den Weyngaert, Danielle; Verellen, Dirk

2015-09-17

Modulation factor (MF) and pitch have an impact on Helical TomoTherapy (HT) plan quality and HT users mostly use vendor-recommended settings. This study analyses the effect of these two parameters on both plan quality and treatment time for plans made with TomoEdge planning software by using the concept of Pareto optimal fronts. More than 450 plans with different combinations of pitch [0.10-0.50] and MF [1.2-3.0] were produced. These HT plans, with a field width (FW) of 5 cm, were created for five head and neck patients and homogeneity index, conformity index, dose-near-maximum (D2), and dose-near-minimum (D98) were analysed for the planning target volumes, as well as the mean dose and D2 for most critical organs at risk. For every dose metric the median value will be plotted against treatment time. A Pareto-like method is used in the analysis which will show how pitch and MF influence both treatment time and plan quality. For small pitches (≤0.20), MF does not influence treatment time. The contrary is true for larger pitches (≥0.25) as lowering MF will both decrease treatment time and plan quality until maximum gantry speed is reached. At this moment, treatment time is saturated and only plan quality will further decrease. The Pareto front analysis showed optimal combinations of pitch [0.23-0.45] and MF > 2.0 for a FW of 5 cm. Outside this range, plans will become less optimal. As the vendor-recommended settings fall within this range, the use of these settings is validated.

11C-Choline PET/CT based Helical Tomotherapy as Treatment Approach for Bone Metastases in Recurrent Prostate Cancer Patients.

PubMed

Incerti, Elena; Gangemi, Vincenzo; Mapelli, Paola; Deantoni, Chiara Lucrezia; Giovacchini, Giampiero; Fallanca, Federico; Fodor, Andrei; Ciarmiello, Andrea; Baldari, Sergio; Gianolli, Luigi; Di Muzio, Nadia; Picchio, Maria

2017-11-10

To evaluate the efficacy of 11C-choline PET/CT (CHO-PET/CT) based helical tomotherapy (HTT) as a therapeutic approach for bone metastases in recurrent prostate cancer (PCa) patients. This retrospective study includes 20 PCa patients (median age: 67; range: 51-80 years) presenting biochemical relapse after primary treatment who underwent CHO-PET/CT based HTT on positive bone metastases from December 2007 to June 2014. The effectiveness of HTT has been assessed with biochemical response at 3/6/12 months, biochemical relapse free survival (bRFS) and overall survival (OS) at 2 years. Toxicity has also been considered and assessed according to Common Terminology Criteria for Adverse Events (CTCAE). All patients presented a relapse at the time of CHO-PET/CT at bone level. In addition 15/20 (75%) also at lymph nodes (LNs) level (total lesions= 54). All patients underwent HTT on bone metastases and 19/20 concomitantly on prostatic bed and LNs. The median follow-up from CHO-PET/CT was 2 years (range: 1-7 years). At 3 months after the beginning of HTT treatment complete or partial biochemical response occurred in 79% of patients, at 6 months in 82% and at 12 months in 63% of patients. bRFS and OS at 2 years were 50% and 55% of patients, respectively. Patients presented mostly grade 1 or 2 toxicity according to CTCAE. The only grade 3 late toxicity has been observed in one patient. CHO-PET/CT based HTT is a suitable therapeutic approach in patients with recurrent PCa presenting bone metastases with a medium-low toxicity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gong, J; Sarwan, R; Pavord, D

Purpose: To quantitatively compare low dose spillage outside of PTV edge in arc therapy modalities Methods: The machines used in the study are Tomotherapy Hi-Arc and Varian 21EX with millennium120 MLC. TPS are TomoPlaning and RayStation for VMAT, respectively. The phantom is a 30cm diameter cylindrical solid water (TOMOTHERAPY, TOMOPHANTOM ASSY). The PTV is 4cm length with ellipsoidal sectional shape with major axis=5cm, minor axis=3cm in the axial plane and reversed in the coronal plane. The PTV volume is created with interpolation. It is located at the center of the phantom. The prescribed dose is 1000x5 cGy to 95% themore » PTV. The isocenter is set co-centered with the PTV. EBT-3 film was used to measure iso-dose lines at the center plane. Film dosimetry is performed with the RIT, v6.2. Results: the study shows: (1) dose falloff gradient is usually uneven, depending on the PTV shape in the gantry rotation plane. For an elliptical shape, the low dose spillage is wider in the minor axis direction than that in the major axis direction. The more a shape is closer to circular, the more even gradient is all directions; (2)for a circular shape (CAX plane in this study), the maximum dose in % of Rx dose at 2cm from PTV is 55% for Tomo, vs. 70% for VMAT (3) the most rapid dose falloff rang is between 95%–80% IDL for both modalities. Conclusion: Tomo has more rapid dose falloff outside of PTV. In some areas, the gradient is double for Tomo helical than that for LINAC VMAT at same points. Future work will examine the differences between optimization of doses and inherent delivery limitations.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, B; Wong, R; Lam, W

Purpose: To develop a practical method for routine QA of the MLC of a Tomotherapy unit using ArcCheck. Methods: Two standard test plans were used in this study. One was a helical test, in which the central leaves No. 32 and 33 opened simultaneously for 277.8ms at projections centered at 0°, 120° and 240° gantry angles. The other test plan was a static test with the gantry angle set at 0°, 45°, 90° and 135° respectively and leaves No. 32 and 33 opened sequentially for total 20s which was further divided into eleven or ten segments at each beam angle.more » The ArcCheck was isocentrically set up and adjusted for couch sag. Movie files which took a snapshot exposure every 50ms were recorded. The start/stop time of leaf open was decided by the ramp-up/ramp-down of the detectors. Results: The percentage differences between measured and planned leaf open time were calculated to be within 0.5% in all the tests. In static test, if leaves are synchronized perfectly, the sum of the two detectors’ signals after normalization should equal one when the leaves are in transition. Our results showed mean values of 0.982, 0.983, 0.978 and 0.995 at static gantry angle 0°, 45°, 90° and 135° respectively. Conclusion: A method for estimating the Tomotherapy binary MLC leaf open time using ArcCheck is proposed and proved to be precise enough to verify the planned leaf open time as small as 277.8ms. This method also makes the observation and quantification of the synchronization of leaves possible.« less

SU-F-T-389: Validation in 4D Dosimetry Using Dynamic Phantom

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, C; Lin, C; Tu, P

2016-06-15

Purpose: Tumor motion due to respiration causes the uncertainties during the radiotherapy. This study aims to find the differences between planning dose by treatment planning and the received dose using dynamic phantom. Methods: Respiratory motion was simulated by the DYNAMIC THORAX PHANTOM (Model 008A). 4D-CT scans and maximum intensity projection (MIP) images for GTV were acquired for analysis. The amplitude of craniocaudal tumor motion including 2mm, 5mm, 10mm and 20mm with 3cm2 tumor size were performed in this study. The respiratory cycles of 4-seconds and 6-seconds were included as the different breathing modes. IMRT, VAMT, and Tomotherapy were utilized formore » treatment planning. Ion chamber and EBT3 were used to measure the point dose and planar dose. Dose distributions with different amplitudes, respiratory cycles, and planning techniques were all measured and compared to calculations. Results: The variations between the does measurements and calculation dose by treatment planning system were found in both point dose and dose distribution. The 0.83% and 5.46 % differences in dose average were shown on phantom with motions using 2mm amplitude in 4 second respiratory cycle, and 20mm amplitude in 4 second respiratory cycle, respectively. The most point dose overestimation as compared of the calculations was shown the plan generated by Tomotherapy. The underestimations of planar dose as compared of calculations was found in the 100% coverage doses for GTV. Conclusion: The loss of complete (100%) GTV coverage was the predominant effect of respiratory motion observed in this study. Motion amplitude and treatment planning system were the major factors leading the dose measurement variation as compared of planning calculations.« less

Critical Structure Sparing in Stereotactic Ablative Radiotherapy for Central Lung Lesions: Helical Tomotherapy vs. Volumetric Modulated Arc Therapy

PubMed Central

Chi, Alexander; Ma, Pan; Fu, Guishan; Hobbs, Gerry; Welsh, James S.; Nguyen, Nam P.; Jang, Si Young; Dai, Jinrong; Jin, Jing; Komaki, Ritsuko

2013-01-01

Background Helical tomotherapy (HT) and volumetric modulated arc therapy (VMAT) are both advanced techniques of delivering intensity-modulated radiotherapy (IMRT). Here, we conduct a study to compare HT and partial-arc VMAT in their ability to spare organs at risk (OARs) when stereotactic ablative radiotherapy (SABR) is delivered to treat centrally located early stage non-small-cell lung cancer or lung metastases. Methods 12 patients with centrally located lung lesions were randomly chosen. HT, 2 & 8 arc (Smart Arc, Pinnacle v9.0) plans were generated to deliver 70 Gy in 10 fractions to the planning target volume (PTV). Target and OAR dose parameters were compared. Each technique’s ability to meet dose constraints was further investigated. Results HT and VMAT plans generated essentially equivalent PTV coverage and dose conformality indices, while a trend for improved dose homogeneity by increasing from 2 to 8 arcs was observed with VMAT. Increasing the number of arcs with VMAT also led to some improvement in OAR sparing. After normalizing to OAR dose constraints, HT was found to be superior to 2 or 8-arc VMAT for optimal OAR sparing (meeting all the dose constraints) (p = 0.0004). All dose constraints were met in HT plans. Increasing from 2 to 8 arcs could not help achieve optimal OAR sparing for 4 patients. 2/4 of them had 3 immediately adjacent structures. Conclusion HT appears to be superior to VMAT in OAR sparing mainly in cases which require conformal dose avoidance of multiple immediately adjacent OARs. For such cases, increasing the number of arcs in VMAT cannot significantly improve OAR sparing. PMID:23577071

MO-G-BRD-01: Point/Counterpoint Debate: Arc Based Techniques Will Make Conventional IMRT Obsolete

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shepard, D; Popple, R; Balter, P

2014-06-15

A variety of intensity modulated radiation therapy (IMRT) delivery techniques have been developed that have provided clinicians with the ability to deliver highly conformal dose distributions. The delivery techniques include compensators, step-and-shoot IMRT, sliding window IMRT, volumetric modulated arc therapy (VMAT), and tomotherapy. A key development in the field of IMRT was the introduction of new planning algorithms and delivery control systems in 2007 that made it possible to coordinate the gantry rotation speed, dose rate, and multileaf collimator leaf positions during the delivery of arc therapy. With these developments, VMAT became a routine clinical tool. The use of VMATmore » has continued to grow in recent years and some would argue that this will soon make conventional IMRT obsolete, and this is the premise of this debate. To introduce the debate, David Shepard, Ph.D. will provide an overview of IMRT delivery techniques including historical context and how they are being used today. The debate will follow with Richard Popple, Ph.D. arguing FOR the Proposition and Peter Balter, Ph.D. arguing AGAINST it. Learning Objectives: Understand the different delivery techniques for IMRT. Understand the potential benefits of conventional IMRT. Understand the potential benefits of arc-based IMRT delivery.« less

Letter to the Editor on 'Single-Arc IMRT?'.

PubMed

Otto, Karl

2009-04-21

In the note 'Single Arc IMRT?' (Bortfeld and Webb 2009 Phys. Med. Biol. 54 N9-20), Bortfeld and Webb present a theoretical investigation of static gantry IMRT (S-IMRT), single-arc IMRT and tomotherapy. Based on their assumptions they conclude that single-arc IMRT is inherently limited in treating complex cases without compromising delivery efficiency. Here we present an expansion of their work based on the capabilities of the Varian RapidArc single-arc IMRT system. Using the same theoretical framework we derive clinically deliverable single-arc IMRT plans based on these specific capabilities. In particular, we consider the range of leaf motion, the ability to rapidly and continuously vary the dose rate and the choice of collimator angle used for delivery. In contrast to the results of Bortfeld and Webb, our results show that single-arc IMRT plans can be generated that closely match the theoretical optimum. The disparity in the results of each investigation emphasizes that the capabilities of the delivery system, along with the ability of the optimization algorithm to exploit those capabilities, are of particular importance in single-arc IMRT. We conclude that, given the capabilities available with the RapidArc system, single-arc IMRT can produce complex treatment plans that are delivered efficiently (in approximately 2 min).

Helical tomotherapy setup variations in canine nasal tumor patients immobilized with a bite block.

PubMed

Kubicek, Lyndsay N; Seo, Songwon; Chappell, Richard J; Jeraj, Robert; Forrest, Lisa J

2012-01-01

The purpose of our study was to compare setup variation in four degrees of freedom (vertical, longitudinal, lateral, and roll) between canine nasal tumor patients immobilized with a mattress and bite block, versus a mattress alone. Our secondary aim was to define a clinical target volume (CTV) to planning target volume (PTV) expansion margin based on our mean systematic error values associated with nasal tumor patients immobilized by a mattress and bite block. We evaluated six parameters for setup corrections: systematic error, random error, patient-patient variation in systematic errors, the magnitude of patient-specific random errors (root mean square [RMS]), distance error, and the variation of setup corrections from zero shift. The variations in all parameters were statistically smaller in the group immobilized by a mattress and bite block. The mean setup corrections in the mattress and bite block group ranged from 0.91 mm to 1.59 mm for the translational errors and 0.5°. Although most veterinary radiation facilities do not have access to Image-guided radiotherapy (IGRT), we identified a need for more rigid fixation, established the value of adding IGRT to veterinary radiation therapy, and define the CTV-PTV setup error margin for canine nasal tumor patients immobilized in a mattress and bite block. © 2012 Veterinary Radiology & Ultrasound.

Poster - Thur Eve - 02: Regulatory oversight of the robotic radiosurgery facilities.

PubMed

Broda, K

2012-07-01

Following a recent review of the Class II Nuclear Facilities and Prescribed Equipment Regulations and regulatory oversight of particle accelerators, the Canadian Nuclear Safety Commission (CNSC) has changed its policy concerning the regulation of particle accelerators. In November 2011, the CNSC began to exercise its regulatory authority with respect to all particle accelerators operating at a beam energy of 1 (one) MeV or greater. The CNSC already licences and inspects particle accelerators capable of operating at or above 10 MeV. The decision to now include low energy particle accelerators (i.e., those operating at or above 1 MeV) ensures adequate, uniform and consistent regulatory oversight for all Class II accelerators. The CNSC expects these facilities to comply with CNSC requirements by December 2013. Besides conventional linear accelerators of lower energy (6 MeV or below) typically found in cancer clinics, two types of equipment now fall under the CNSC's regulatory oversight as a result of the above change: robotic radiosurgery and tomotherapy equipment and facilities. A number of clinics in Canada already operates these types of equipment and facilities. The safety aspects of radiosurgery equipment differ slightly from those for conventional linear accelerators. This poster aims to present an approach taken by the CNSC to regulate robotic radiosurgery equipment and facilities. The presentation will explain how to meet regulatory requirements of the Class II Nuclear Facilities and Prescribed Equipment Regulations by licensees operating or planning to acquire these types of equipment and facilities. © 2012 American Association of Physicists in Medicine.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mwidu, U; Devic, S; Shehadeh, M

Purpose: A retrospective comparison of dose distributions achievable by High dose rate brachytherapy (HDRBT), Helical TomoTherapy (TOMO), CyberKnife (CK) and RapidArc (RA) in locally advanced inoperable cervical cancer patients is presented. Methods: Five patients with advanced stage cervical carcinoma were selected for this study after a full course of external beam radiotherapy (EBRT), chemotherapy and HDR Brachytherapy. To highlight any significant similarities/differences in dose distributions, high-risk clinical target volume (HRCTV) coverage, organs at risk (OAR) sparing, and machine specific delivery limitations, we used D90 (dose received by 90% of the volume) as the parameter for HRCTV coverage as recommended bymore » the GEC-ESTRO Working Group. We also compared both integral and differential dose volume histograms (DVH) between different dose distributions treatment modalities for HRCTV and OAR. Results: TOMO and RA provided the most conformal dose distributions to HRCTV. Median doses (in Gy) to organs at risk were; for rectal wall: 1.7±0.6, 2.5±0.6,1.2±0.3, and 1.5±0.6, and for bladder wall: 1.6±0.1, 2.4±0.4, 0.8±0.6, and 1.5±0.5, for HDRBT, TOMO, CK, and RA, respectively. Conclusion: Contemporary EBRT modalities might be able to replace brachytherapy treatments for cervix cancer. While brachytherapy dose distributions feature high dose gradients, EBRT modalities provide highly conformal dose distributions to the target. However, it is still not clear whether a highly conformal dose or high gradient dose is more clinically relevant for the HRCTV in cervix cancer patients.« less

Proton therapy for locally advanced breast cancer: A systematic review of the literature.

PubMed

Kammerer, Emmanuel; Guevelou, Jennifer Le; Chaikh, Abdulhamid; Danhier, Serge; Geffrelot, Julien; Levy, Christelle; Saloux, Eric; Habrand, Jean-Louis; Thariat, Juliette

2018-02-01

Radiation therapy plays a major role in the management of adjuvant breast cancer with nodal involvement, with an iatrogenic increase of cardio-vascular risk. Photon therapy, even with intensity modulation, has the downsides of high mean heart dose and heterogeneous target coverage, particularly in the case of internal mammary irradiation. This systematic review of the literature aims to evaluate proton therapy in locally advanced breast cancer. PubMed was searched for original full-text articles with the following search terms: «Proton Therapy» and «Breast Cancer». On-going trials were collected using the words "Breast Cancer" and "Protons". 13 articles met the criteria: 6 with passive proton therapy (Double Scattering), 5 with Pencil Beam Scanning (PBS) and 2 with a combination of both. Proton therapy offered a better target coverage than photons, even compared with intensity modulation radiation therapy (including static or rotational IMRT or tomotherapy). With proton therapy, volumes receiving 95% of the dose were around 98%, with low volumes receiving 105% of the dose. Proton therapy often decreased mean heart dose by a factor of 2 or 3, i.e. 1 Gy with proton therapy versus 3 Gy with conventional 3D, and 6 Gy for IMRT. Lungs were better spared with proton therapy than with photon therapy. Cutaneous toxicity observed with double scattering is improved with PBS. Proton therapy reduces mean heart dose in breast cancer irradiation, probably reducing late cardio-vascular toxicity. Large clinical studies will likely confirm a clinical benefit of proton therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

ARCHERRT – A GPU-based and photon-electron coupled Monte Carlo dose computing engine for radiation therapy: Software development and application to helical tomotherapy

PubMed Central

Su, Lin; Yang, Youming; Bednarz, Bryan; Sterpin, Edmond; Du, Xining; Liu, Tianyu; Ji, Wei; Xu, X. George

2014-01-01

Purpose: Using the graphical processing units (GPU) hardware technology, an extremely fast Monte Carlo (MC) code ARCHERRT is developed for radiation dose calculations in radiation therapy. This paper describes the detailed software development and testing for three clinical TomoTherapy® cases: the prostate, lung, and head & neck. Methods: To obtain clinically relevant dose distributions, phase space files (PSFs) created from optimized radiation therapy treatment plan fluence maps were used as the input to ARCHERRT. Patient-specific phantoms were constructed from patient CT images. Batch simulations were employed to facilitate the time-consuming task of loading large PSFs, and to improve the estimation of statistical uncertainty. Furthermore, two different Woodcock tracking algorithms were implemented and their relative performance was compared. The dose curves of an Elekta accelerator PSF incident on a homogeneous water phantom were benchmarked against DOSXYZnrc. For each of the treatment cases, dose volume histograms and isodose maps were produced from ARCHERRT and the general-purpose code, GEANT4. The gamma index analysis was performed to evaluate the similarity of voxel doses obtained from these two codes. The hardware accelerators used in this study are one NVIDIA K20 GPU, one NVIDIA K40 GPU, and six NVIDIA M2090 GPUs. In addition, to make a fairer comparison of the CPU and GPU performance, a multithreaded CPU code was developed using OpenMP and tested on an Intel E5-2620 CPU. Results: For the water phantom, the depth dose curve and dose profiles from ARCHERRT agree well with DOSXYZnrc. For clinical cases, results from ARCHERRT are compared with those from GEANT4 and good agreement is observed. Gamma index test is performed for voxels whose dose is greater than 10% of maximum dose. For 2%/2mm criteria, the passing rates for the prostate, lung case, and head & neck cases are 99.7%, 98.5%, and 97.2%, respectively. Due to specific architecture of GPU, modified Woodcock tracking algorithm performed inferior to the original one. ARCHERRT achieves a fast speed for PSF-based dose calculations. With a single M2090 card, the simulations cost about 60, 50, 80 s for three cases, respectively, with the 1% statistical error in the PTV. Using the latest K40 card, the simulations are 1.7–1.8 times faster. More impressively, six M2090 cards could finish the simulations in 8.9–13.4 s. For comparison, the same simulations on Intel E5-2620 (12 hyperthreading) cost about 500–800 s. Conclusions: ARCHERRT was developed successfully to perform fast and accurate MC dose calculation for radiotherapy using PSFs and patient CT phantoms. PMID:24989378

ARCHERRT - a GPU-based and photon-electron coupled Monte Carlo dose computing engine for radiation therapy: software development and application to helical tomotherapy.

PubMed

Su, Lin; Yang, Youming; Bednarz, Bryan; Sterpin, Edmond; Du, Xining; Liu, Tianyu; Ji, Wei; Xu, X George

2014-07-01

Using the graphical processing units (GPU) hardware technology, an extremely fast Monte Carlo (MC) code ARCHERRT is developed for radiation dose calculations in radiation therapy. This paper describes the detailed software development and testing for three clinical TomoTherapy® cases: the prostate, lung, and head & neck. To obtain clinically relevant dose distributions, phase space files (PSFs) created from optimized radiation therapy treatment plan fluence maps were used as the input to ARCHERRT. Patient-specific phantoms were constructed from patient CT images. Batch simulations were employed to facilitate the time-consuming task of loading large PSFs, and to improve the estimation of statistical uncertainty. Furthermore, two different Woodcock tracking algorithms were implemented and their relative performance was compared. The dose curves of an Elekta accelerator PSF incident on a homogeneous water phantom were benchmarked against DOSXYZnrc. For each of the treatment cases, dose volume histograms and isodose maps were produced from ARCHERRT and the general-purpose code, GEANT4. The gamma index analysis was performed to evaluate the similarity of voxel doses obtained from these two codes. The hardware accelerators used in this study are one NVIDIA K20 GPU, one NVIDIA K40 GPU, and six NVIDIA M2090 GPUs. In addition, to make a fairer comparison of the CPU and GPU performance, a multithreaded CPU code was developed using OpenMP and tested on an Intel E5-2620 CPU. For the water phantom, the depth dose curve and dose profiles from ARCHERRT agree well with DOSXYZnrc. For clinical cases, results from ARCHERRT are compared with those from GEANT4 and good agreement is observed. Gamma index test is performed for voxels whose dose is greater than 10% of maximum dose. For 2%/2mm criteria, the passing rates for the prostate, lung case, and head & neck cases are 99.7%, 98.5%, and 97.2%, respectively. Due to specific architecture of GPU, modified Woodcock tracking algorithm performed inferior to the original one. ARCHERRT achieves a fast speed for PSF-based dose calculations. With a single M2090 card, the simulations cost about 60, 50, 80 s for three cases, respectively, with the 1% statistical error in the PTV. Using the latest K40 card, the simulations are 1.7-1.8 times faster. More impressively, six M2090 cards could finish the simulations in 8.9-13.4 s. For comparison, the same simulations on Intel E5-2620 (12 hyperthreading) cost about 500-800 s. ARCHERRT was developed successfully to perform fast and accurate MC dose calculation for radiotherapy using PSFs and patient CT phantoms.

Helical Tomotherapy for Whole-Brain Irradiation With Integrated Boost to Multiple Brain Metastases: Evaluation of Dose Distribution Characteristics and Comparison With Alternative Techniques

DOE Office of Scientific and Technical Information (OSTI.GOV)

Levegrün, Sabine, E-mail: sabine.levegruen@uni-due.de; Pöttgen, Christoph; Wittig, Andrea

2013-07-15

Purpose: To quantitatively evaluate dose distribution characteristics achieved with helical tomotherapy (HT) for whole-brain irradiation (WBRT) with integrated boost (IB) to multiple brain metastases in comparison with alternative techniques. Methods and Materials: Dose distributions for 23 patients with 81 metastases treated with WBRT (30 Gy/10 fractions) and IB (50 Gy) were analyzed. The median number of metastases per patient (N{sub mets}) was 3 (range, 2-8). Mean values of the composite planning target volume of all metastases per patient (PTV{sub mets}) and of the individual metastasis planning target volume (PTV{sub ind} {sub met}) were 8.7 ± 8.9 cm{sup 3} (range, 1.3-35.5more » cm{sup 3}) and 2.5 ± 4.5 cm{sup 3} (range, 0.19-24.7 cm{sup 3}), respectively. Dose distributions in PTV{sub mets} and PTV{sub ind} {sub met} were evaluated with respect to dose conformity (conformation number [CN], RTOG conformity index [PITV]), target coverage (TC), and homogeneity (homogeneity index [HI], ratio of maximum dose to prescription dose [MDPD]). The dependence of dose conformity on target size and N{sub mets} was investigated. The dose distribution characteristics were benchmarked against alternative irradiation techniques identified in a systematic literature review. Results: Mean ± standard deviation of dose distribution characteristics derived for PTV{sub mets} amounted to CN = 0.790 ± 0.101, PITV = 1.161 ± 0.154, TC = 0.95 ± 0.01, HI = 0.142 ± 0.022, and MDPD = 1.147 ± 0.029, respectively, demonstrating high dose conformity with acceptable homogeneity. Corresponding numbers for PTV{sub ind} {sub met} were CN = 0.708 ± 0.128, PITV = 1.174 ± 0.237, TC = 0.90 ± 0.10, HI = 0.140 ± 0.027, and MDPD = 1.129 ± 0.030, respectively. The target size had a statistically significant influence on dose conformity to PTV{sub mets} (CN = 0.737 for PTV{sub mets} ≤4.32 cm{sup 3} vs CN = 0.848 for PTV{sub mets} >4.32 cm{sup 3}, P=.006), in contrast to N{sub mets}. The achieved dose conformity to PTV{sub mets}, assessed by both CN and PITV, was in all investigated volume strata well within the best quartile of the values reported for alternative irradiation techniques. Conclusions: HT is a well-suited technique to deliver WBRT with IB to multiple brain metastases, yielding high-quality dose distributions. A multi-institutional prospective randomized phase 2 clinical trial to exploit efficacy and safety of the treatment concept is currently under way.« less

Integrating: A managerial practice that enables implementation in fragmented health care environments.

PubMed

Kerrissey, Michaela; Satterstrom, Patricia; Leydon, Nicholas; Schiff, Gordon; Singer, Sara

How some organizations improve while others remain stagnant is a key question in health care research. Studies identifying how organizations can implement improvement despite barriers are needed, particularly in primary care. This inductive qualitative study examines primary care clinics implementing improvement efforts in order to identify mechanisms that enable implementation despite common barriers, such as lack of time and fragmentation across stakeholder groups. Using an embedded multiple case study design, we leverage a longitudinal data set of field notes, meeting minutes, and interviews from 16 primary care clinics implementing improvement over 15 months. We segment clinics into those that implemented more versus those that implemented less, comparing similarities and differences. We identify interpersonal mechanisms promoting implementation, develop a conceptual model of our key findings, and test the relationship with performance using patient surveys conducted pre-/post-implementation. Nine clinics implemented more successfully over the study period, whereas seven implemented less. Successfully implementing clinics exhibited the managerial practice of integrating, which we define as achieving unity of effort among stakeholder groups in the pursuit of a shared and mutually developed goal. We theorize that integrating is critical in improvement implementation because of the fragmentation observed in health care settings, and we extend theory about clinic managers' role in implementation. We identify four integrating mechanisms that clinic managers enacted: engaging groups, bridging communication, sensemaking, and negotiating. The mean patient survey results for integrating clinics improved by 0.07 units over time, whereas the other clinics' survey scores declined by 0.08 units on a scale of 5 (p = .02). Our research explores an understudied element of how clinics can implement improvement despite barriers: integrating stakeholders within and outside the clinic into the process. It provides clinic managers with an actionable path for implementing improvement.

Helical Tomotherapy vs. Intensity-Modulated Proton Therapy for Whole Pelvis Irradiation in High-Risk Prostate Cancer Patients: Dosimetric, Normal Tissue Complication Probability, and Generalized Equivalent Uniform Dose Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Widesott, Lamberto, E-mail: widesott@yahoo.it; Pierelli, Alessio; Fiorino, Claudio

2011-08-01

Purpose: To compare intensity-modulated proton therapy (IMPT) and helical tomotherapy (HT) treatment plans for high-risk prostate cancer (HRPCa) patients. Methods and Materials: The plans of 8 patients with HRPCa treated with HT were compared with IMPT plans with two quasilateral fields set up (-100{sup o}; 100{sup o}) and optimized with the Hyperion treatment planning system. Both techniques were optimized to simultaneously deliver 74.2 Gy/Gy relative biologic effectiveness (RBE) in 28 fractions on planning target volumes (PTVs)3-4 (P + proximal seminal vesicles), 65.5 Gy/Gy(RBE) on PTV2 (distal seminal vesicles and rectum/prostate overlapping), and 51.8 Gy/Gy(RBE) to PTV1 (pelvic lymph nodes). Normalmore » tissue calculation probability (NTCP) calculations were performed for the rectum, and generalized equivalent uniform dose (gEUD) was estimated for the bowel cavity, penile bulb and bladder. Results: A slightly better PTV coverage and homogeneity of target dose distribution with IMPT was found: the percentage of PTV volume receiving {>=}95% of the prescribed dose (V{sub 95%}) was on average >97% in HT and >99% in IMPT. The conformity indexes were significantly lower for protons than for photons, and there was a statistically significant reduction of the IMPT dosimetric parameters, up to 50 Gy/Gy(RBE) for the rectum and bowel and 60 Gy/Gy(RBE) for the bladder. The NTCP values for the rectum were higher in HT for all the sets of parameters, but the gain was small and in only a few cases statistically significant. Conclusions: Comparable PTV coverage was observed. Based on NTCP calculation, IMPT is expected to allow a small reduction in rectal toxicity, and a significant dosimetric gain with IMPT, both in medium-dose and in low-dose range in all OARs, was observed.« less

A computer simulated phantom study of tomotherapy dose optimization based on probability density functions (PDF) and potential errors caused by low reproducibility of PDF.

PubMed

Sheng, Ke; Cai, Jing; Brookeman, James; Molloy, Janelle; Christopher, John; Read, Paul

2006-09-01

Lung tumor motion trajectories measured by four-dimensional CT or dynamic MRI can be converted to a probability density function (PDF), which describes the probability of the tumor at a certain position, for PDF based treatment planning. Using this method in simulated sequential tomotherapy, we study the dose reduction of normal tissues and more important, the effect of PDF reproducibility on the accuracy of dosimetry. For these purposes, realistic PDFs were obtained from two dynamic MRI scans of a healthy volunteer within a 2 week interval. The first PDF was accumulated from a 300 s scan and the second PDF was calculated from variable scan times from 5 s (one breathing cycle) to 300 s. Optimized beam fluences based on the second PDF were delivered to the hypothetical gross target volume (GTV) of a lung phantom that moved following the first PDF The reproducibility between two PDFs varied from low (78%) to high (94.8%) when the second scan time increased from 5 s to 300 s. When a highly reproducible PDF was used in optimization, the dose coverage of GTV was maintained; phantom lung receiving 10%-20% prescription dose was reduced by 40%-50% and the mean phantom lung dose was reduced by 9.6%. However, optimization based on PDF with low reproducibility resulted in a 50% underdosed GTV. The dosimetric error increased nearly exponentially as the PDF error increased. Therefore, although the dose of the tumor surrounding tissue can be theoretically reduced by PDF based treatment planning, the reliability and applicability of this method highly depend on if a reproducible PDF exists and is measurable. By correlating the dosimetric error and PDF error together, a useful guideline for PDF data acquisition and patient qualification for PDF based planning can be derived.

Mild Lung Restriction in Breast Cancer Patients After Hypofractionated and Conventional Radiation Therapy: A 3-Year Follow-Up

DOE Office of Scientific and Technical Information (OSTI.GOV)

Verbanck, Sylvia, E-mail: sylvia.verbanck@uzbrussel.be; Hanon, Shane; Schuermans, Daniel

Purpose: To assess the effect of radiation therapy on lung function over the course of 3 years. Methods and Materials: Evolution of restrictive and obstructive lung function parameters was investigated in 108 breast cancer participants in a randomized, controlled trial comparing conventional radiation therapy (CR) and hypofractionated tomotherapy (TT) (age at inclusion ranging 32-81 years). Spirometry, plethysmography, and hemoglobin-corrected diffusing capacity were assessed at baseline and after 3 months and 1, 2, and 3 years. Natural aging was accounted for by considering all lung function parameters in terms of percent predicted values using the most recent reference values for women aged up to 80 years. Results:more » In the patients with negligible history of respiratory disease or smoking (n=77), the greatest rate of functional decline was observed during the initial 3 months, this acute decrease being more marked in the CR versus the TT arm. During the remainder of the 3-year follow-up period, values (in terms of percent predicted) were maintained (diffusing capacity) or continued to decline at a slower rate (forced vital capacity). However, the average decline of the restrictive lung function parameters over a 3-year period did not exceed 9% predicted in either the TT or the CR arm. Obstructive lung function parameters remained unaffected throughout. Including also the 31 patients with a history of respiratory disease or more than 10 pack-years showed a very similar restrictive pattern. Conclusions: In women with breast cancer, both conventional radiation therapy and hypofractionated tomotherapy induce small but consistent restrictive lung patterns over the course of a 3-year period, irrespective of baseline respiratory status or smoking history. The fastest rate of lung function decline generally occurred in the first 3 months.« less

Therapeutic benefits in grid irradiation on Tomotherapy for bulky, radiation-resistant tumors.

PubMed

Narayanasamy, Ganesh; Zhang, Xin; Meigooni, Ali; Paudel, Nava; Morrill, Steven; Maraboyina, Sanjay; Peacock, Loverd; Penagaricano, Jose

2017-08-01

Spatially fractionated radiation therapy (SFRT or grid therapy) has proven to be effective in management of bulky tumors. The aim of this project is to study the therapeutic ratio (TR) of helical Tomotherapy (HT)-based grid therapy using linear-quadratic cell survival model. HT-based grid (or HT-GRID) plan was generated using a patient-specific virtual grid pattern of high-dose cylindrical regions using MLCs. TR was defined as the ratio of normal tissue surviving fraction (SF) under HT-GRID irradiation to an open debulking field of an equivalent dose that result in the same tumor cell SF. TR was estimated from DVH data on ten HT-GRID patient plans with deep seated, bulky tumor. Dependence of the TR values on radiosensitivity of the tumor cells and prescription dose was analyzed. The mean ± standard deviation (SD) of TR was 4.0 ± 0.7 (range: 3.1-5.5) for the 10 patients with single fraction maximum dose of 20 Gy to GTV assuming a tumor cell SF at 2 Gy (SF2 t ) value of 0·5. In addition, the mean ± SD of TR values for SF2 t values of 0.3 and 0.7 were found to be 1 ± 0.1 and 18.0 ± 5.1, respectively. Reducing the prescription dose to 15 and 10 Gy lowered the respective TR values to 2.0 ± 0.2 and 1.2 ± 0.04 for a SF2 t value of 0.5. HT-GRID therapy demonstrates a significant therapeutic advantage over uniform dose from an open field irradiation for the same tumor cell kill. TR increases with the radioresistance of the tumor cells and with prescription dose.

SU-E-T-472: Improvement of IMRT QA Passing Rate by Correcting Angular Dependence of MatriXX

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Q; Watkins, W; Kim, T

2015-06-15

Purpose: Multi-channel planar detector arrays utilized for IMRT-QA, such as the MatriXX, exhibit an incident-beam angular dependent response which can Result in false-positive gamma-based QA results, especially for helical tomotherapy plans which encompass the full range of beam angles. Although MatriXX can use with gantry angle sensor to provide automatically angular correction, this sensor does not work with tomotherapy. The purpose of the study is to reduce IMRT-QA false-positives by correcting for the MatriXX angular dependence. Methods: MatriXX angular dependence was characterized by comparing multiple fixed-angle irradiation measurements with corresponding TPS computed doses. For 81 Tomo-helical IMRT-QA measurements, two differentmore » correction schemes were tested: (1) A Monte-Carlo dose engine was used to compute MatriXX signal based on the angular-response curve. The computed signal was then compared with measurement. (2) Uncorrected computed signal was compared with measurements uniformly scaled to account for the average angular dependence. Three scaling factor (+2%, +2.5%, +3%) were tested. Results: The MatriXX response is 8% less than predicted for a PA beam even when the couch is fully accounted for. Without angular correction, only 67% of the cases pass the >90% points γ<1 (3%, 3mm). After full angular correction, 96% of the cases pass the criteria. Of three scaling factors, +2% gave the highest passing rate (89%), which is still less than the full angular correction method. With a stricter γ(2%,3mm) criteria, the full angular correction method was still able to achieve the 90% passing rate while the scaling method only gives 53% passing rate. Conclusion: Correction for the MatriXX angular dependence reduced the false-positives rate of our IMRT-QA process. It is necessary to correct for the angular dependence to achieve the IMRT passing criteria specified in TG129.« less

Bowel sparing in pediatric cranio-spinal radiotherapy: a comparison of combined electron and photon and helical TomoTherapy techniques to a standard photon method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harron, Elizabeth, E-mail: elizabeth.harron@nuh.nhs.uk; Lewis, Joanne

2012-07-01

The aim of this study was to compare the dose to organs at risk (OARs) from different craniospinal radiotherapy treatment approaches available at the Northern Centre for Cancer Care (NCCC), with a particular emphasis on sparing the bowel. Method: Treatment plans were produced for a pediatric medulloblastoma patient with inflammatory bowel disease using 3D conformal 6-MV photons (3DCP), combined 3D 6-MV photons and 18-MeV electrons (3DPE), and helical photon TomoTherapy (HT). The 3DPE plan was a modification of the standard 3DCP technique, using electrons to treat the spine inferior to the level of the diaphragm. The plans were compared inmore » terms of the dose-volume data to OARs and the nontumor integral dose. Results: The 3DPE plan was found to give the lowest dose to the bowel and the lowest nontumor integral dose of the 3 techniques. However, the coverage of the spine planning target volume (PTV) was least homogeneous using this technique, with only 74.6% of the PTV covered by 95% of the prescribed dose. HT was able to achieve the best coverage of the PTVs (99.0% of the whole-brain PTV and 93.1% of the spine PTV received 95% of the prescribed dose), but delivered a significantly higher integral dose. HT was able to spare the heart, thyroid, and eyes better than the linac-based techniques, but other OARs received a higher dose. Conclusions: Use of electrons was the best method for reducing the dose to the bowel and the integral dose, at the expense of compromised spine PTV coverage. For some patients, HT may be a viable method of improving dose homogeneity and reducing selected OAR doses.« less

SU-F-T-489: 4-Years Experience of QA in TomoTherapy MVCT: What Do We Look Out For?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, F; Chan, K

2016-06-15

Purpose: To evaluate the QA results of TomoTherapy MVCT from March 2012 to February 2016, and to identify issues that may affect consistency in HU numbers and reconstructed treatment dose in MVCT. Methods: Monthly QA was performed on our TomoHD system. Phantom with rod inserts of various mass densities was imaged in MVCT and compared to baseline to evaluate HU number consistency. To evaluate treatment dose reconstructed by delivered sinogram and MVCT, a treatment plan was designed on a humanoid skull phantom. The phantom was imaged with MVCT and treatment plan was delivered to obtain the sinogram. The dose reconstructedmore » with the Planned Adaptive software was compared to the dose in the original plan. The QA tolerance for HU numbers was ±30 HU, and ±2% for discrepancy between original plan dose and reconstructed dose. Tolerances were referenced to AAPM TG148. Results: Several technical modifications or maintenance activities to the system have been identified which affected QA Results: 1) Upgrade in console system software which added a weekly HU calibration procedure; 2) Linac or MLC replacement leading to change in Accelerator Output Machine (AOM) parameters; 3) Upgrade in planning system algorithm affecting MVCT dose reconstruction. These events caused abrupt changes in QA results especially for the reconstructed dose. In the past 9 months, when no such modifications were done to the system, reconstructed dose was consistent with maximum deviation from baseline less than 0.6%. The HU number deviated less than 5HU. Conclusion: Routine QA is essential for MVCT, especially if the MVCT is used for daily dose reconstruction to monitor delivered dose to patients. Several technical events which may affect consistency of this are software changes, linac or MLC replacement. QA results reflected changes which justify re-calibration or system adjustment. In normal circumstances, the system should be relatively stable and quarterly QA may be sufficient.« less

Helical Tomotherapy in Head and Neck Cancer: A European Single-Center Experience

PubMed Central

Van den Weyngaert, Danielle; De Kerf, Geert; De Ost, Bie; Vanderveken, Olivier; Van Laer, Carl; Specenier, Pol; Geussens, Yasmyne; Wouters, Kristien; Meulemans, Els; Cheung, Kin Jip; Grégoire, Vincent; Vermorken, Jan B.

2015-01-01

Background. We report on a retrospective analysis of 147 patients with early and locoregionally advanced squamous cell head and neck cancer (SCCHN) treated with helical tomotherapy (HT). Patients and Methods. Included were patients with SCCHN of the oral cavity (OC), oropharynx (OP), hypopharynx (HP), or larynx (L) consecutively treated in one radiotherapy center in 2008 and 2009. The prescribed HT dose was 60–66 Gy in the postoperative setting (group A) and 66–70 Gy when given as primary treatment (group B). HT was given alone, concurrent with systemic therapy (ST), that is, chemotherapy, biotherapy, or both, and with or without induction therapy (IT). Acute and late toxicities are reported using standard criteria; locoregional failure/progression (LRF), distant metastases (DM), and second primary tumors (SPT) were documented, and event-free survival (EFS) and overall survival (OS) were calculated from the start of HT. Results. Group A patients received HT alone in 22 cases and HT + ST in 20 cases; group B patients received HT alone in 17 cases and HT + ST in 88 cases. Severe (grade ≥ 3) acute mucosal toxicity and swallowing problems increased with more additional ST. After a median follow-up of 44 months, grade ≥2 late toxicity after HT + ST was approximately twice that of HT alone for skin, subcutis, pharynx, and larynx. Forty percent had grade ≥2 late xerostomia, and 29% had mucosal toxicity. At 3 years, LRF/DM/SPT occurred in 7%/7%/17% and 25%/13%/5% in groups A and B, respectively, leading to a 3-year EFS/OS of 64%/74% and 56%/63% in groups A and B, respectively. Conclusion. The use of HT alone or in combination with ST is feasible and promising and has a low late fatality rate. However, late toxicity is nearly twice as high when ST is added to HT. PMID:25673104

Phase I Trial of Simultaneous In-Field Boost With Helical Tomotherapy for Patients With One to Three Brain Metastases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rodrigues, George, E-mail: george.rodrigues@lhsc.on.ca; Yartsev, Slav; Yaremko, Brian

2011-07-15

Purpose: Stereotactic radiosurgery is an alternative to surgical resection for selected intracranial lesions. Integrated image-guided intensity-modulated-capable radiotherapy platforms such as helical tomotherapy (HT) could potentially replace traditional radiosurgery apparatus. The present study's objective was to determine the maximally tolerated dose of a simultaneous in-field boost integrated with whole brain radiotherapy for palliative treatment of patients with one to three brain metastases using HT. Methods and Materials: The inclusion/exclusion criteria and endpoints were consistent with the Radiation Therapy Oncology Group 9508 radiosurgery trial. The cohorts were constructed with a 3 + 3 design; however, additional patients were enrolled in the lowermore » dose tolerable cohorts during the toxicity assessment periods. Whole brain radiotherapy (30 Gy in 10 fractions) was delivered with a 5-30-Gy (total lesion dose of 35-60 Gy in 10 fractions) simultaneous in-field boost delivered to the brain metastases. The maximally tolerated dose was determined by the frequency of neurologic Grade 3-5 National Cancer Institute Common Toxicity Criteria, version 3.0, dose-limiting toxicity events within each Phase I cohort. Results: A total of 48 patients received treatment in the 35-Gy (n = 3), 40-Gy (n = 16), 50-Gy (n = 15), 55-Gy (n = 8), and 60-Gy (n = 6) cohorts. No patients experienced dose-limiting toxicity events in any of the trial cohorts. The 3-month RECIST assessments available for 32 of the 48 patients demonstrated a complete response in 2, a partial response in 16, stable disease in 6, and progressive disease in 8 patients. Conclusion: The delivery of 60 Gy in 10 fractions to one to three brain metastases synchronously with 30 Gy whole brain radiotherapy was achieved without dose-limiting central nervous system toxicity as assessed 3 months after treatment. This approach is being tested in a Phase II efficacy trial.« less

A computer simulated phantom study of tomotherapy dose optimization based on probability density functions (PDF) and potential errors caused by low reproducibility of PDF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheng, Ke; Cai Jing; Brookeman, James

2006-09-15

Lung tumor motion trajectories measured by four-dimensional CT or dynamic MRI can be converted to a probability density function (PDF), which describes the probability of the tumor at a certain position, for PDF based treatment planning. Using this method in simulated sequential tomotherapy, we study the dose reduction of normal tissues and more important, the effect of PDF reproducibility on the accuracy of dosimetry. For these purposes, realistic PDFs were obtained from two dynamic MRI scans of a healthy volunteer within a 2 week interval. The first PDF was accumulated from a 300 s scan and the second PDF wasmore » calculated from variable scan times from 5 s (one breathing cycle) to 300 s. Optimized beam fluences based on the second PDF were delivered to the hypothetical gross target volume (GTV) of a lung phantom that moved following the first PDF. The reproducibility between two PDFs varied from low (78%) to high (94.8%) when the second scan time increased from 5 s to 300 s. When a highly reproducible PDF was used in optimization, the dose coverage of GTV was maintained; phantom lung receiving 10%-20% prescription dose was reduced by 40%-50% and the mean phantom lung dose was reduced by 9.6%. However, optimization based on PDF with low reproducibility resulted in a 50% underdosed GTV. The dosimetric error increased nearly exponentially as the PDF error increased. Therefore, although the dose of the tumor surrounding tissue can be theoretically reduced by PDF based treatment planning, the reliability and applicability of this method highly depend on if a reproducible PDF exists and is measurable. By correlating the dosimetric error and PDF error together, a useful guideline for PDF data acquisition and patient qualification for PDF based planning can be derived.« less

TU-H-BRC-07: Therapeutic Benefit in Spatially Fractionated Radiotherapy (GRID) Using Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narayanasamy, G; Zhang, X; Paudel, N

Purpose: The aim of this project is to study the therapeutic ratio (TR) for helical Tomotherapy (HT) based spatially fractionated radiotherapy (GRID). Estimation of TR was based on the linear-quadratic cell survival model by comparing the normal cell survival in a HT GRID to that of a uniform dose delivery in an open-field for the same tumor survival. Methods: HT GRID plan was generated using a patient specific virtual GRID block pattern of non-divergent, cylinder shaped holes using MLCs. TR was defined as the ratio of normal tissue surviving fraction (SF) under HT GRID irradiation to an open field irradiationmore » with an equivalent dose that result in the same tumor cell SF. The ratio was estimated from DVH data on ten patient plans with deep seated, bulky tumor approved by the treating radiation oncologist. Dependence of the TR values on radio-sensitivity of the tumor cells and prescription dose were also analyzed. Results: The mean ± standard deviation (SD) of TR was 4.0±0.7 (range: 3.1 to 5.5) for the 10 patients with single fraction dose of 20 Gy and tumor cell SF of 0.5 at 2 Gy. In addition, mean±SD of TR = 1±0.1 and 18.0±5.1 were found for tumor with SF of 0.3 and 0.7, respectively. Reducing the prescription dose to 15 and 10 Gy lowered the TR to 2.0±0.2 and 1.2±0.04 for a tumor cell SF of 0.5 at 2 Gy. In this study, the SF of normal cells was assumed to be 0.5 at 2 Gy. Conclusion: HT GRID displayed a significant therapeutic advantage over uniform dose from an open field irradiation. TR increases with the radioresistance of the tumor cells and with prescription dose.« less

Successful delivery of adjuvant external beam radiotherapy for ependymoma in a patient with Ondine's curse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, Mehee; Thoma, Miranda; Tolekidis, George

Ondine's curse is a rare, potentially life-threatening disorder characterized by loss of automatic breathing during sleep and preserved voluntary breathing. It is seldom encountered in the radiotherapy clinic but can pose significant technical challenges and safety concerns in the delivery of a prescribed radiation course. We report a unique case of successful delivery of radiotherapy for ependymoma in a patient with Ondine's curse. A 53-year-old gentleman presented with vertigo when lying down. Brain magnetic resonance imaging revealed an enhancing mass in the floor of the fourth ventricle. He underwent maximal safe resection. Pathology revealed ependymoma. The patient was referred formore » radiotherapy. Computed tomography simulation was performed in supine position with 3-point thermoplastic mask immobilization. Sequential TomoTherapy plans were developed. At first scheduled treatment, shortly after mask placement, his arms went limp and he was unresponsive. Vitals showed oxygen saturation 83%, pulse 127, and blood pressure 172/97 mm Hg. He was diagnosed with Ondine's curse thought secondary to previous brainstem damage; the combination of lying flat and pressure from the mask was causing him to go into respiratory arrest. As supine positioning did not seem clinically advisable, he was simulated in prone position. A RapidArc plan and a back-up conformal plan were developed. Prescriptions were modified to meet conservative organs-at-risk constraints. Several strategies were used to minimize uncertainties in set-up reproducibility associated with prone positioning. He tolerated prone RapidArc treatments well. The report highlights the importance of applying practical patient safety and treatment planning/delivery strategies in the management of this challenging case.« less

Comparison of the helical tomotherapy against the multileaf collimator-based intensity-modulated radiotherapy and 3D conformal radiation modalities in lung cancer radiotherapy

PubMed Central

Mavroidis, P; Shi, C; Plataniotis, G A; Delichas, M G; Costa Ferreira, B; Rodriguez, S; Lind, B K; Papanikolaou, N

2011-01-01

Objectives The aim of this study was to compare three-dimensional (3D) conformal radiotherapy and the two different forms of IMRT in lung cancer radiotherapy. Methods Cases of four lung cancer patients were investigated by developing a 3D conformal treatment plan, a linac MLC-based step-and-shoot IMRT plan and an HT plan for each case. With the use of the complication-free tumour control probability (P+) index and the uniform dose concept as the common prescription point of the plans, the different treatment plans were compared based on radiobiological measures. Results The applied plan evaluation method shows the MLC-based IMRT and the HT treatment plans are almost equivalent over the clinically useful dose prescription range; however, the 3D conformal plan inferior. At the optimal dose levels, the 3D conformal treatment plans give an average P+ of 48.1% for a effective uniform dose to the internal target volume (ITV) of 62.4 Gy, whereas the corresponding MLC-based IMRT treatment plans are more effective by an average ΔP+ of 27.0% for a Δ effective uniform dose of 16.3 Gy. Similarly, the HT treatment plans are more effective than the 3D-conformal plans by an average ΔP+ of 23.8% for a Δ effective uniform dose of 11.6 Gy. Conclusion A radiobiological treatment plan evaluation can provide a closer association of the delivered treatment with the clinical outcome by taking into account the dose–response relations of the irradiated tumours and normal tissues. The use of P – effective uniform dose diagrams can complement the traditional tools of evaluation to compare and effectively evaluate different treatment plans. PMID:20858664

Re-Irradiation of Hepatocellular Carcinoma: Clinical Applicability of Deformable Image Registration.

PubMed

Lee, Dong Soo; Woo, Joong Yeol; Kim, Jun Won; Seong, Jinsil

2016-01-01

This study aimed to evaluate whether the deformable image registration (DIR) method is clinically applicable to the safe delivery of re-irradiation in hepatocellular carcinoma (HCC). Between August 2010 and March 2012, 12 eligible HCC patients received re-irradiation using helical tomotherapy. The median total prescribed radiation doses at first irradiation and re-irradiation were 50 Gy (range, 36-60 Gy) and 50 Gy (range, 36-58.42 Gy), respectively. Most re-irradiation therapies (11 of 12) were administered to previously irradiated or marginal areas. Dose summation results were reproduced using DIR by rigid and deformable registration methods, and doses of organs-at-risk (OARs) were evaluated. Treatment outcomes were also assessed. Thirty-six dose summation indices were obtained for three OARs (bowel, duodenum, and stomach doses in each patient). There was no statistical difference between the two different types of DIR methods (rigid and deformable) in terms of calculated summation ΣD (0.1 cc, 1 cc, 2 cc, and max) in each OAR. The median total mean remaining liver doses (M(RLD)) in rigid- and deformable-type registration were not statistically different for all cohorts (p=0.248), although a large difference in M(RLD) was observed when there was a significant difference in spatial liver volume change between radiation intervals. One duodenal ulcer perforation developed 20 months after re-irradiation. Although current dose summation algorithms and uncertainties do not warrant accurate dosimetric results, OARs-based DIR dose summation can be usefully utilized in the re-irradiation of HCC. Appropriate cohort selection, watchful interpretation, and selective use of DIR methods are crucial to enhance the radio-therapeutic ratio.

Implementation Science Supports Core Clinical Competencies: An Overview and Clinical Example.

PubMed

Kirchner, JoAnn E; Woodward, Eva N; Smith, Jeffrey L; Curran, Geoffrey M; Kilbourne, Amy M; Owen, Richard R; Bauer, Mark S

2016-12-08

Instead of asking clinicians to work faster or longer to improve quality of care, implementation science provides another option. Implementation science is an emerging interdisciplinary field dedicated to studying how evidence-based practice can be adopted into routine clinical care. This article summarizes principles and methods of implementation science, illustrates how they can be applied in a routine clinical setting, and highlights their importance to practicing clinicians as well as clinical trainees. A hypothetical clinical case scenario is presented that explains how implementation science improves clinical practice. The case scenario is also embedded within a real-world implementation study to improve metabolic monitoring for individuals prescribed antipsychotics. Context, recipient, and innovation (ie, the evidence-based practice) factors affected improvement of metabolic monitoring. To address these factors, an external facilitator and a local quality improvement team developed an implementation plan involving a multicomponent implementation strategy that included education, performance reports, and clinician follow-up. The clinic remained compliant with recommended metabolic monitoring at 1-year follow up. Implementation science improves clinical practice by addressing context, recipient, and innovation factors and uses this information to develop and utilize specific strategies that improve clinical practice. It also enriches clinical training, aligning with core competencies by the Accreditation Council for Graduate Medical Education and American Boards of Medical Specialties. By learning how to change clinical practice through implementation strategies, clinicians are more able to adapt in complex systems of practice. © Copyright 2016 Physicians Postgraduate Press, Inc.

ARCHER{sub RT} – A GPU-based and photon-electron coupled Monte Carlo dose computing engine for radiation therapy: Software development and application to helical tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Su, Lin; Du, Xining; Liu, Tianyu

Purpose: Using the graphical processing units (GPU) hardware technology, an extremely fast Monte Carlo (MC) code ARCHER{sub RT} is developed for radiation dose calculations in radiation therapy. This paper describes the detailed software development and testing for three clinical TomoTherapy® cases: the prostate, lung, and head and neck. Methods: To obtain clinically relevant dose distributions, phase space files (PSFs) created from optimized radiation therapy treatment plan fluence maps were used as the input to ARCHER{sub RT}. Patient-specific phantoms were constructed from patient CT images. Batch simulations were employed to facilitate the time-consuming task of loading large PSFs, and to improvemore » the estimation of statistical uncertainty. Furthermore, two different Woodcock tracking algorithms were implemented and their relative performance was compared. The dose curves of an Elekta accelerator PSF incident on a homogeneous water phantom were benchmarked against DOSXYZnrc. For each of the treatment cases, dose volume histograms and isodose maps were produced from ARCHER{sub RT} and the general-purpose code, GEANT4. The gamma index analysis was performed to evaluate the similarity of voxel doses obtained from these two codes. The hardware accelerators used in this study are one NVIDIA K20 GPU, one NVIDIA K40 GPU, and six NVIDIA M2090 GPUs. In addition, to make a fairer comparison of the CPU and GPU performance, a multithreaded CPU code was developed using OpenMP and tested on an Intel E5-2620 CPU. Results: For the water phantom, the depth dose curve and dose profiles from ARCHER{sub RT} agree well with DOSXYZnrc. For clinical cases, results from ARCHER{sub RT} are compared with those from GEANT4 and good agreement is observed. Gamma index test is performed for voxels whose dose is greater than 10% of maximum dose. For 2%/2mm criteria, the passing rates for the prostate, lung case, and head and neck cases are 99.7%, 98.5%, and 97.2%, respectively. Due to specific architecture of GPU, modified Woodcock tracking algorithm performed inferior to the original one. ARCHER{sub RT} achieves a fast speed for PSF-based dose calculations. With a single M2090 card, the simulations cost about 60, 50, 80 s for three cases, respectively, with the 1% statistical error in the PTV. Using the latest K40 card, the simulations are 1.7–1.8 times faster. More impressively, six M2090 cards could finish the simulations in 8.9–13.4 s. For comparison, the same simulations on Intel E5-2620 (12 hyperthreading) cost about 500–800 s. Conclusions: ARCHER{sub RT} was developed successfully to perform fast and accurate MC dose calculation for radiotherapy using PSFs and patient CT phantoms.« less

Best strategies to implement clinical pathways in an emergency department setting: study protocol for a cluster randomized controlled trial.

PubMed

Jabbour, Mona; Curran, Janet; Scott, Shannon D; Guttman, Astrid; Rotter, Thomas; Ducharme, Francine M; Lougheed, M Diane; McNaughton-Filion, M Louise; Newton, Amanda; Shafir, Mark; Paprica, Alison; Klassen, Terry; Taljaard, Monica; Grimshaw, Jeremy; Johnson, David W

2013-05-22

The clinical pathway is a tool that operationalizes best evidence recommendations and clinical practice guidelines in an accessible format for 'point of care' management by multidisciplinary health teams in hospital settings. While high-quality, expert-developed clinical pathways have many potential benefits, their impact has been limited by variable implementation strategies and suboptimal research designs. Best strategies for implementing pathways into hospital settings remain unknown. This study will seek to develop and comprehensively evaluate best strategies for effective local implementation of externally developed expert clinical pathways. We will develop a theory-based and knowledge user-informed intervention strategy to implement two pediatric clinical pathways: asthma and gastroenteritis. Using a balanced incomplete block design, we will randomize 16 community emergency departments to receive the intervention for one clinical pathway and serve as control for the alternate clinical pathway, thus conducting two cluster randomized controlled trials to evaluate this implementation intervention. A minimization procedure will be used to randomize sites. Intervention sites will receive a tailored strategy to support full clinical pathway implementation. We will evaluate implementation strategy effectiveness through measurement of relevant process and clinical outcomes. The primary process outcome will be the presence of an appropriately completed clinical pathway on the chart for relevant patients. Primary clinical outcomes for each clinical pathway include the following: Asthma--the proportion of asthmatic patients treated appropriately with corticosteroids in the emergency department and at discharge; and Gastroenteritis--the proportion of relevant patients appropriately treated with oral rehydration therapy. Data sources include chart audits, administrative databases, environmental scans, and qualitative interviews. We will also conduct an overall process evaluation to assess the implementation strategy and an economic analysis to evaluate implementation costs and benefits. This study will contribute to the body of evidence supporting effective strategies for clinical pathway implementation, and ultimately reducing the research to practice gaps by operationalizing best evidence care recommendations through effective use of clinical pathways. ClinicalTrials.gov: NCT01815710.

Technical note: patient-specific quality assurance methods for TomoDirect(TM) whole breast treatment delivery.

PubMed

Catuzzo, P; Zenone, F; Aimonetto, S; Peruzzo, A; Casanova Borca, V; Pasquino, M; Franco, P; La Porta, M R; Ricardi, U; Tofani, S

2012-07-01

To investigate the feasibility of implementing a novel approach for patient-specific QA of TomoDirect(TM) whole breast treatment. The most currently used TomoTherapy DQA method, consisting in the verification of the 2D dose distribution in a coronal or sagittal plane of the Cheese Phantom by means of gafchromic films, was compared with an alternative approach based on the use of two commercially available diode arrays, MapCHECK2(TM) and ArcCHECK(TM). The TomoDirect(TM) plans of twenty patients with a primary unilateral breast cancer were applied to a CT scan of the Cheese Phantom and a MVCT dataset of the diode arrays. Then measurements of 2D dose distribution were performed and compared with the calculated ones using the gamma analysis method with different sets of DTA and DD criteria (3%-3 mm, 3%-2 mm). The sensitivity of the diode arrays to detect delivery and setup errors was also investigated. The measured dose distributions showed excellent agreement with the TPS calculations for each detector, with averaged fractions of passed Γ values greater than 95%. The percentage of points satisfying the constraint Γ < 1 was significantly higher for MapCHECK2(TM) than for ArcCHECK(TM) and gafchromic films using both the 3%-3 mm and 3%-2 mm gamma criteria. Both the diode arrays show a good sensitivity to delivery and setup errors using a 3%-2 mm gamma criteria. MapCHECK2™ and ArcCHECK(TM) may fulfill the demands of an adequate system for TomoDirect(TM) patient-specific QA.

Effectiveness-implementation hybrid designs: combining elements of clinical effectiveness and implementation research to enhance public health impact.

PubMed

Curran, Geoffrey M; Bauer, Mark; Mittman, Brian; Pyne, Jeffrey M; Stetler, Cheryl

2012-03-01

This study proposes methods for blending design components of clinical effectiveness and implementation research. Such blending can provide benefits over pursuing these lines of research independently; for example, more rapid translational gains, more effective implementation strategies, and more useful information for decision makers. This study proposes a "hybrid effectiveness-implementation" typology, describes a rationale for their use, outlines the design decisions that must be faced, and provides several real-world examples. An effectiveness-implementation hybrid design is one that takes a dual focus a priori in assessing clinical effectiveness and implementation. We propose 3 hybrid types: (1) testing effects of a clinical intervention on relevant outcomes while observing and gathering information on implementation; (2) dual testing of clinical and implementation interventions/strategies; and (3) testing of an implementation strategy while observing and gathering information on the clinical intervention's impact on relevant outcomes. The hybrid typology proposed herein must be considered a construct still in evolution. Although traditional clinical effectiveness and implementation trials are likely to remain the most common approach to moving a clinical intervention through from efficacy research to public health impact, judicious use of the proposed hybrid designs could speed the translation of research findings into routine practice.

Creation of an atlas of filter positions for fluence field modulated CT.

PubMed

Szczykutowicz, Timothy P; Hermus, James

2015-04-01

Fluence field modulated CT (FFMCT) and volume of interest (VOI) CT imaging applications require adjustment of the profile of the x-ray fluence incident on a patient as a function of view angle. Since current FFMCT prototypes can theoretically take on an infinite number of configurations, measuring a calibration data set for all possible positions would not be feasible. The present work details a methodology for calculating an atlas of configurations that will span all likely body regions, patient sizes, patient positioning, and imaging modes. The hypothesis is that there exists a finite number of unique modulator configurations that effectively span the infinite number of possible fluence profiles with minimal loss in performance. CT images of a head, shoulder, thorax, abdominal, wrist, and leg anatomical slices were dilated and contracted to model small, medium, and large sized patients. Additionally, the images were positioned from iso-center by three different amounts. The modulator configurations required to compensate for each image were computed assuming a FFMCT prototype, digital beam attenuator, (DBA), was set to equalize the detector exposure. Each atlas configuration should be different from the other atlas configurations. The degree of difference was quantified using the sum of the absolute differences in filter thickness between configurations. Using this metric, a set of unique wedge configurations for which no two configurations have a metric value smaller than some threshold can be constructed. Differences in the total number of incident photons between the unconstrained filters and the atlas were studied as a function of the number of atlas positions for each anatomical site and size/off-centering combination. By varying the threshold used in creating the atlas, it was found that roughly 322 atlas positions provided an incident number of photons within 20% of using 19,440 unique filters (the number of atlas entries ranged from 7213 to 1). Additionally, for VOI applications implemented with a single VOI region, the number of required filter configurations was expressed in a simple closed form solution. The methodology proposed in this work will enable DBA-FFMCT and DBA-VOI imaging in the clinic without the need for patient specific air-scans to be performed. In addition, the methodology proposed here is directly applicable to other modulator designs such as piecewise linear, TomoTherapy multi leaf collimators, 2D fluid arrays, and inverse geometry CT.

EDITORIAL: International Workshop on Monte Carlo Techniques in Radiotherapy Delivery and Verification

NASA Astrophysics Data System (ADS)

Verhaegen, Frank; Seuntjens, Jan

2008-03-01

Monte Carlo particle transport techniques offer exciting tools for radiotherapy research, where they play an increasingly important role. Topics of research related to clinical applications range from treatment planning, motion and registration studies, brachytherapy, verification imaging and dosimetry. The International Workshop on Monte Carlo Techniques in Radiotherapy Delivery and Verification took place in a hotel in Montreal in French Canada, from 29 May-1 June 2007, and was the third workshop to be held on a related topic, which now seems to have become a tri-annual event. About one hundred workers from many different countries participated in the four-day meeting. Seventeen experts in the field were invited to review topics and present their latest work. About half of the audience was made up by young graduate students. In a very full program, 57 papers were presented and 10 posters were on display during most of the meeting. On the evening of the third day a boat trip around the island of Montreal allowed participants to enjoy the city views, and to sample the local cuisine. The topics covered at the workshop included the latest developments in the most popular Monte Carlo transport algorithms, fast Monte Carlo, statistical issues, source modeling, MC treatment planning, modeling of imaging devices for treatment verification, registration and deformation of images and a sizeable number of contributions on brachytherapy. In this volume you will find 27 short papers resulting from the workshop on a variety of topics, some of them on very new stuff such as graphics processing units for fast computing, PET modeling, dual-energy CT, calculations in dynamic phantoms, tomotherapy devices, . . . . We acknowledge the financial support of the National Cancer Institute of Canada, the Institute of Cancer Research of the Canadian Institutes of Health Research, the Association Québécoise des Physicien(ne)s Médicaux Clinique, the Institute of Physics, and MedicalPhysicsWeb. At McGill we thank the following departments for support: the Cancer Axis of the Research Institute of the McGill University Health Center, the Faculties of Medicine and Science, the Departments of Oncology and Physics and the Medical Physics Unit. The following companies are thanked: TomoTherapy and Standard Imaging. The American Association of Physicists in Medicine and the International Atomic Energy Agency are gratefully acknowledged for endorsing the meeting. A final word of thanks goes out to all of those who contributed to the successful Workshop: first of all our administrative assistant Ms Margery Knewstubb, the website developer Dr François DeBlois, the two heads of the logistics team, Ms Emily Poon and Ms Emily Heath, our local medical physics students and staff, the IOP staff and the authors who shared their new and exciting work with us. Editors: Frank Verhaegen and Jan Seuntjens (McGill University) Associate editors: Luc Beaulieu, Iwan Kawrakow, Tony Popescu and David Rogers

Implementing a Measurement Feedback System in Community Mental Health Clinics: A Case Study of Multilevel Barriers and Facilitators

PubMed Central

Gleacher, Alissa A.; Olin, Serene S.; Nadeem, Erum; Pollock, Michele; Ringle, Vanesa; Bickman, Leonard; Douglas, Susan; Hoagwood, Kimberly

2015-01-01

Measurement feedback systems (MFSs) have been proposed as a means of improving practice. The present study examined the implementation of a MFS, the Contextualized Feedback System (CFS), in two community-based clinic sites. Significant implementation differences across sites provided a basis for examining factors that influenced clinician uptake of CFS. Following the theoretical implementation framework of Aarons, Hurlburt & Horwitz (2011), we coded qualitative data collected from eighteen clinicians (13 from Clinic U and 5 from Clinic R) who participated in semi-structured interviews about their experience with CFS implementation. Results suggest that clinicians at both clinics perceived more barriers than facilitators to CFS implementation. Interestingly, clinicians at the higher implementing clinic reported a higher proportion of barriers to facilitators (3:1 vs. 2:1); however, these clinicians also reported a significantly higher level of organizational and leadership supports for CFS implementation. Implications of these findings are discussed. PMID:25735619

Best strategies to implement clinical pathways in an emergency department setting: study protocol for a cluster randomized controlled trial

PubMed Central

2013-01-01

Background The clinical pathway is a tool that operationalizes best evidence recommendations and clinical practice guidelines in an accessible format for ‘point of care’ management by multidisciplinary health teams in hospital settings. While high-quality, expert-developed clinical pathways have many potential benefits, their impact has been limited by variable implementation strategies and suboptimal research designs. Best strategies for implementing pathways into hospital settings remain unknown. This study will seek to develop and comprehensively evaluate best strategies for effective local implementation of externally developed expert clinical pathways. Design/methods We will develop a theory-based and knowledge user-informed intervention strategy to implement two pediatric clinical pathways: asthma and gastroenteritis. Using a balanced incomplete block design, we will randomize 16 community emergency departments to receive the intervention for one clinical pathway and serve as control for the alternate clinical pathway, thus conducting two cluster randomized controlled trials to evaluate this implementation intervention. A minimization procedure will be used to randomize sites. Intervention sites will receive a tailored strategy to support full clinical pathway implementation. We will evaluate implementation strategy effectiveness through measurement of relevant process and clinical outcomes. The primary process outcome will be the presence of an appropriately completed clinical pathway on the chart for relevant patients. Primary clinical outcomes for each clinical pathway include the following: Asthma—the proportion of asthmatic patients treated appropriately with corticosteroids in the emergency department and at discharge; and Gastroenteritis—the proportion of relevant patients appropriately treated with oral rehydration therapy. Data sources include chart audits, administrative databases, environmental scans, and qualitative interviews. We will also conduct an overall process evaluation to assess the implementation strategy and an economic analysis to evaluate implementation costs and benefits. Discussion This study will contribute to the body of evidence supporting effective strategies for clinical pathway implementation, and ultimately reducing the research to practice gaps by operationalizing best evidence care recommendations through effective use of clinical pathways. Trial registration ClinicalTrials.gov: NCT01815710 PMID:23692634

EMRs and Clinical IS Implementation in Hospitals: A Statewide Survey

ERIC Educational Resources Information Center

Jaana, Mirou; Ward, Marcia M.; Bahensky, James A.

2012-01-01

Purpose: Present an overview of clinical information systems (IS) in hospitals and analyze the level of electronic medical records (EMR) implementation in relation to clinical IS capabilities and organizational characteristics. Methods: We developed a survey instrument measuring clinical IS implementation and classified clinical IS across 5 EMR…

Three-dimensional analysis of the respiratory interplay effect in helical tomotherapy: Baseline variations cause the greater part of dose inhomogeneities seen.

PubMed

Tudor, G Samuel J; Harden, Susan V; Thomas, Simon J

2014-03-01

Dose differences from those planned can occur due to the respiratory interplay effect on helical tomotherapy. The authors present a technique to calculate single-fraction doses in three-dimensions resulting from craniocaudal motion applied to a patient CT set. The technique is applied to phantom and patient plans using patient respiratory traces. An additional purpose of the work is to determine the contribution toward the interplay effect of different components of the respiratory trace. MATLAB code used to calculate doses to a CT dataset from a helical tomotherapy plan has been modified to permit craniocaudal motion and improved temporal resolution. Real patient traces from seven patients were applied to ten phantom plans of differing field width, modulation factor, pitch and fraction dose, and simulations made with peak-to-peak amplitudes ranging from 0 to 2.5 cm. PTV voxels near the superior or inferior limits of the PTV are excluded from the analysis. The maximum dose discrepancy compared with the static case recorded along with the proportion of voxels receiving more than 10% and 20% different from prescription dose. The analysis was repeated with the baseline variation of the respiratory trace removed, leaving the cyclic component of motion only. Radiochromic film was used on one plan-trace combination and compared with the software simulation. For one case, filtered traces were generated and used in simulations which consisted only of frequencies near to particular characteristic frequencies of the treatment delivery. Intraslice standard deviation of dose differences was used to identify potential MLC interplay, which was confirmed using nonmodulated simulations. Software calculations were also conducted for four realistic patient plans and modeling movement of a patient CT set with amplitudes informed by the observed motion of the GTV on 4DCT. The maximum magnitude of dose difference to a PTV voxel due to the interplay effect within a particular plan-trace combination for peak-to-peak amplitudes of up to 2.5 cm ranged from 4.5% to 51.6% (mean: 23.8%) of the dose delivered in the absence of respiratory motion. For cyclic motion only, the maximum dose differences in each combination ranged from 2.1% to 26.2% (mean: 9.2%). There is reasonable correspondence between an example of the phantom plan simulations and radiochromic film measurement. The filtered trace simulations revealed that frequencies close to the characteristic frequency of the jaw motion across the target were found to generate greater interplay effect than frequencies close to the gantry frequency or MLC motion. There was evidence of interplay between respiratory motion and MLC modulation, but this is small compared with the interplay between respiratory motion and jaw motion. For patient-plan simulations, dose discrepancies are seen of up to 9.0% for a patient with 0.3 cm peak-to-peak respiratory amplitude and up to 17.7% for a patient with 0.9 cm peak-to-peak amplitude. These values reduced to 1.3% and 6.5%, respectively, when only cyclic motion was considered. Software has been developed to simulate craniocaudal respiratory motion in phantom and patient plans using real patient respiratory traces. Decomposition of the traces into baseline andcyclic components reveals that the large majority of the interplay effect seen with the full trace is due to baseline variation during treatment.

The relationship between baseline Organizational Readiness to Change Assessment subscale scores and implementation of hepatitis prevention services in substance use disorders treatment clinics: a case study

PubMed Central

2010-01-01

Background The Organizational Readiness to Change Assessment (ORCA) is a measure of organizational readiness for implementing practice change in healthcare settings that is organized based on the core elements and sub-elements of the Promoting Action on Research Implementation in Health Services (PARIHS) framework. General support for the reliability and factor structure of the ORCA has been reported. However, no published study has examined the utility of the ORCA in a clinical setting. The purpose of the current study was to examine the relationship between baseline ORCA scores and implementation of hepatitis prevention services in substance use disorders (SUD) clinics. Methods Nine clinic teams from Veterans Health Administration SUD clinics across the United States participated in a six-month training program to promote evidence-based practices for hepatitis prevention. A representative from each team completed the ORCA evidence and context subscales at baseline. Results Eight of nine clinics reported implementation of at least one new hepatitis prevention practice after completing the six-month training program. Clinic teams were categorized by level of implementation-high (n = 4) versus low (n = 5)-based on how many hepatitis prevention practices were integrated into their clinics after completing the training program. High implementation teams had significantly higher scores on the patient experience and leadership culture subscales of the ORCA compared to low implementation teams. While not reaching significance in this small sample, high implementation clinics also had higher scores on the research, clinical experience, staff culture, leadership behavior, and measurement subscales as compared to low implementation clinics. Conclusions The results of this study suggest that the ORCA was able to measure differences in organizational factors at baseline between clinics that reported high and low implementation of practice recommendations at follow-up. This supports the use of the ORCA to describe factors related to implementing practice recommendations in clinical settings. Future research utilizing larger sample sizes will be essential to support these preliminary findings. PMID:20546584

A knowledge-based approach to automated planning for hepatocellular carcinoma.

PubMed

Zhang, Yujie; Li, Tingting; Xiao, Han; Ji, Weixing; Guo, Ming; Zeng, Zhaochong; Zhang, Jianying

2018-01-01

To build a knowledge-based model of liver cancer for Auto-Planning, a function in Pinnacle, which is used as an automated inverse intensity modulated radiation therapy (IMRT) planning system. Fifty Tomotherapy patients were enrolled to extract the dose-volume histograms (DVHs) information and construct the protocol for Auto-Planning model. Twenty more patients were chosen additionally to test the model. Manual planning and automatic planning were performed blindly for all twenty test patients with the same machine and treatment planning system. The dose distributions of target and organs at risks (OARs), along with the working time for planning, were evaluated. Statistically significant results showed that automated plans performed better in target conformity index (CI) while mean target dose was 0.5 Gy higher than manual plans. The differences between target homogeneity indexes (HI) of the two methods were not statistically significant. Additionally, the doses of normal liver, left kidney, and small bowel were significantly reduced with automated plan. Particularly, mean dose and V15 of normal liver were 1.4 Gy and 40.5 cc lower with automated plans respectively. Mean doses of left kidney and small bowel were reduced with automated plans by 1.2 Gy and 2.1 Gy respectively. In contrast, working time was also significantly reduced with automated planning. Auto-Planning shows availability and effectiveness in our knowledge-based model for liver cancer. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Measuring dose from radiotherapy treatments in the vicinity of a cardiac pacemaker.

PubMed

Peet, Samuel C; Wilks, Rachael; Kairn, Tanya; Crowe, Scott B

2016-12-01

This study investigated the dose absorbed by tissues surrounding artificial cardiac pacemakers during external beam radiotherapy procedures. The usefulness of out-of-field reference data, treatment planning systems, and skin dose measurements to estimate the dose in the vicinity of a pacemaker was also examined. Measurements were performed by installing a pacemaker onto an anthropomorphic phantom, and using radiochromic film and optically stimulated luminescence dosimeters to measure the dose in the vicinity of the device during the delivery of square fields and clinical treatment plans. It was found that the dose delivered in the vicinity of the cardiac device was unevenly distributed both laterally and anteroposteriorly. As the device was moved distally from the square field, the dose dropped exponentially, in line with out-of-field reference data in the literature. Treatment planning systems were found to substantially underestimate the dose for volumetric modulated arc therapy, helical tomotherapy, and 3D conformal treatments. The skin dose was observed to be either greater or lesser than the dose received at the depth of the device, depending on the treatment site, and so care should be if skin dose measurements are to be used to estimate the dose to a pacemaker. Square field reference data may be used as an upper estimate of absorbed dose per monitor unit in the vicinity of a cardiac device for complex treatments involving multiple gantry angles. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Effectiveness-implementation Hybrid Designs

PubMed Central

Curran, Geoffrey M.; Bauer, Mark; Mittman, Brian; Pyne, Jeffrey M.; Stetler, Cheryl

2013-01-01

Objectives This study proposes methods for blending design components of clinical effectiveness and implementation research. Such blending can provide benefits over pursuing these lines of research independently; for example, more rapid translational gains, more effective implementation strategies, and more useful information for decision makers. This study proposes a “hybrid effectiveness-implementation” typology, describes a rationale for their use, outlines the design decisions that must be faced, and provides several real-world examples. Results An effectiveness-implementation hybrid design is one that takes a dual focus a priori in assessing clinical effectiveness and implementation. We propose 3 hybrid types: (1) testing effects of a clinical intervention on relevant outcomes while observing and gathering information on implementation; (2) dual testing of clinical and implementation interventions/strategies; and (3) testing of an implementation strategy while observing and gathering information on the clinical intervention’s impact on relevant outcomes. Conclusions The hybrid typology proposed herein must be considered a construct still in evolution. Although traditional clinical effectiveness and implementation trials are likely to remain the most common approach to moving a clinical intervention through from efficacy research to public health impact, judicious use of the proposed hybrid designs could speed the translation of research findings into routine practice. PMID:22310560

Implementing a Measurement Feedback System in Community Mental Health Clinics: A Case Study of Multilevel Barriers and Facilitators.

PubMed

Gleacher, Alissa A; Olin, Serene S; Nadeem, Erum; Pollock, Michele; Ringle, Vanesa; Bickman, Leonard; Douglas, Susan; Hoagwood, Kimberly

2016-05-01

Measurement feedback systems (MFSs) have been proposed as a means of improving practice. The present study examined the implementation of a MFS, the Contextualized Feedback System (CFS), in two community-based clinic sites. Significant implementation differences across sites provided a basis for examining factors that influenced clinician uptake of CFS. Following the theoretical implementation framework of Aarons et al. (Adm Policy Mental Health Mental Health Serv Res 38(1):4-23, 2011), we coded qualitative data collected from eighteen clinicians (13 from Clinic U and 5 from Clinic R) who participated in semi-structured interviews about their experience with CFS implementation. Results suggest that clinicians at both clinics perceived more barriers than facilitators to CFS implementation. Interestingly, clinicians at the higher implementing clinic reported a higher proportion of barriers to facilitators (3:1 vs. 2:1); however, these clinicians also reported a significantly higher level of organizational and leadership supports for CFS implementation. Implications of these findings are discussed.

Implementation of a clinical innovation: the case of advanced clinic access in the Department of Veterans Affairs.

PubMed

Lukas, Carol VanDeusen; Meterko, Mark M; Mohr, David; Seibert, Marjorie Nealon; Parlier, Renee; Levesque, Odette; Petzel, Robert A

2008-01-01

Healthcare organizations seeking to improve clinical practices often have disappointing results because the planned innovations are not successfully implemented. To increase the understanding of implementation, we analyzed the national spread of an ambulatory innovation in the Department of Veterans Affairs. This study provides support for a conceptual model that posits that the extent to which a clinical innovation is implemented will be affected by factors in 3 domains: (1) intentional activities to introduce, spread, and support the innovation; (2) the attitudes and capabilities of clinic staff responsible for implementing the innovation; and (3) the context of the facility in which the innovation is being introduced. Among the strongest predictors of successful implementation, management support for the innovation and clinic team knowledge and skills to make changes successfully were significant across both primary care and specialty clinics.

Systems consultation: protocol for a novel implementation strategy designed to promote evidence-based practice in primary care.

PubMed

Quanbeck, Andrew; Brown, Randall T; E Zgierska, Aleksandra; A Johnson, Roberta; Robinson, James M; Jacobson, Nora

2016-01-27

Adoption of evidence-based practices takes place at a glacial place in healthcare. This research will pilot test an innovative implementation strategy - systems consultation -intended to speed the adoption of evidence-based practice in primary care. The strategy is based on tenets of systems engineering and has been extensively tested in addiction treatment. Three innovations have been included in the strategy - translation of a clinical practice guideline into a checklist-based implementation guide, the use of physician peer coaches ('systems consultants') to help clinics implement the guide, and a focus on reducing variation in practices across prescribers and clinics. The implementation strategy will be applied to improving opioid prescribing practices in primary care, which may help ultimately mitigate the increasing prevalence of opioid abuse and addiction. The pilot test will compare four intervention clinics to four control clinics in a matched-pairs design. A leading clinical guideline for opioid prescribing has been translated into a checklist-based implementation guide in a systematic process that involved experts who wrote the guideline in consultation with implementation experts and primary care physicians. Two physicians with expertise in family and addiction medicine are serving as the systems consultants. Each systems consultant will guide two intervention clinics, using two site visits and follow-up communication by phone and email, to implement the translated guideline. Mixed methods will be used to test the feasibility, acceptability, and preliminary effectiveness of the implementation strategy in an evaluation that meets standards for 'fully developed use' of the RE-AIM framework (Reach, Effectiveness, Adoption, Implementation, Maintenance). The clinic will be the primary unit of analysis. The systems consultation implementation strategy is intended to generalize to the adoption of other clinical guidelines. This pilot test is intended to prepare for a large randomized clinical trial that will test the strategy against other implementation strategies, such as audit/feedback and academic detailing, used to close the gap between knowledge and practice. The systems consultation approach has the potential to shorten the famously long time it takes to implement evidence-based practices and clinical guidelines in healthcare.

Implementation of Health Insurance Support Tools in Community Health Centers.

PubMed

Huguet, Nathalie; Hatch, Brigit; Sumic, Aleksandra; Tillotson, Carrie; Hicks, Elizabeth; Nelson, Joan; DeVoe, Jennifer E

2018-01-01

Health information technology (HIT) provides new opportunities for primary care clinics to support patients with health insurance enrollment and maintenance. We present strategies, early findings, and clinic reflections on the development and implementation of HIT tools designed to streamline and improve health insurance tracking at community health centers. We are conducting a hybrid implementation-effectiveness trial to assess novel health insurance enrollment and support tools in primary care clinics. Twenty-three clinics in 7 health centers from the OCHIN practice-based research network are participating in the implementation component of the trial. Participating health centers were randomized to 1 of 2 levels of implementation support, including arm 1 (n = 4 health centers, 11 clinic sites) that received HIT tools and educational materials and arm 2 (n = 3 health centers, 12 clinic sites) that received HIT tools, educational materials, and individualized implementation support with a practice coach. We used mixed-methods (qualitative and quantitative) to assess tool use rates and facilitators and barriers to implementation in the first 6 months. Clinics reported favorable attitudes toward the HIT tools, which replace less efficient and more cumbersome processes, and reflect on the importance of clinic engagement in tool development and refinement. Five of 7 health centers are now regularly using the tools and are actively working to increase tool use. Six months after formal implementation, arm 2 clinics demonstrated higher rates of tool use, compared with arm 1. These results highlight the value of early clinic input in tool development, the potential benefit of practice coaching during HIT tool development and implementation, and a novel method for coupling a hybrid implementation-effectiveness design with principles of improvement science in primary care research. © Copyright 2018 by the American Board of Family Medicine.

The Pharmacogenomics Research Network Translational Pharmacogenetics Program: Outcomes and Metrics of Pharmacogenetic Implementations Across Diverse Healthcare Systems.

PubMed

Luzum, J A; Pakyz, R E; Elsey, A R; Haidar, C E; Peterson, J F; Whirl-Carrillo, M; Handelman, S K; Palmer, K; Pulley, J M; Beller, M; Schildcrout, J S; Field, J R; Weitzel, K W; Cooper-DeHoff, R M; Cavallari, L H; O'Donnell, P H; Altman, R B; Pereira, N; Ratain, M J; Roden, D M; Embi, P J; Sadee, W; Klein, T E; Johnson, J A; Relling, M V; Wang, L; Weinshilboum, R M; Shuldiner, A R; Freimuth, R R

2017-09-01

Numerous pharmacogenetic clinical guidelines and recommendations have been published, but barriers have hindered the clinical implementation of pharmacogenetics. The Translational Pharmacogenetics Program (TPP) of the National Institutes of Health (NIH) Pharmacogenomics Research Network was established in 2011 to catalog and contribute to the development of pharmacogenetic implementations at eight US healthcare systems, with the goal to disseminate real-world solutions for the barriers to clinical pharmacogenetic implementation. The TPP collected and normalized pharmacogenetic implementation metrics through June 2015, including gene-drug pairs implemented, interpretations of alleles and diplotypes, numbers of tests performed and actionable results, and workflow diagrams. TPP participant institutions developed diverse solutions to overcome many barriers, but the use of Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines provided some consistency among the institutions. The TPP also collected some pharmacogenetic implementation outcomes (scientific, educational, financial, and informatics), which may inform healthcare systems seeking to implement their own pharmacogenetic testing programs. © 2017, The American Society for Clinical Pharmacology and Therapeutics.

Efficacy of virtual block objects in reducing the lung dose in helical tomotherapy planning for cervical oesophageal cancer: a planning study.

PubMed

Ito, Makoto; Shimizu, Hidetoshi; Aoyama, Takahiro; Tachibana, Hiroyuki; Tomita, Natsuo; Makita, Chiyoko; Koide, Yutaro; Kato, Daiki; Ishiguchi, Tsuneo; Kodaira, Takeshi

2018-04-04

Intensity-modulated radiotherapy is useful for cervical oesophageal carcinoma (CEC); however, increasing low-dose exposure to the lung may lead to radiation pneumonitis. Nevertheless, an irradiation technique that avoids the lungs has never been examined due to the high difficulty of dose optimization. In this study, we examined the efficacy of helical tomotherapy that can restrict beamlets passing virtual blocks during dose optimization computing (block plan) in reducing the lung dose. Fifteen patients with CEC were analysed. The primary/nodal lesion and prophylactic nodal region with adequate margins were defined as the planning target volume (PTV)-60 Gy and PTV-48 Gy, respectively. Nineteen plans per patient were made and compared (total: 285 plans), including non-block and block plans with several shapes and sizes. The most appropriate block model was semi-circular, 8 cm outside of the tracheal bifurcation, with a significantly lower lung dose compared to that of non-block plans; the mean lung volumes receiving 5 Gy, 10 Gy, 20 Gy, and the mean lung dose were 31.3% vs. 48.0% (p <  0.001), 22.4% vs. 39.4% (p <  0.001), 13.2% vs. 16.0% (p = 0.028), and 7.1 Gy vs. 9.6 Gy (p <  0.001), respectively. Both the block and non-block plans were comparable in terms of the homogeneity and conformity indexes of PTV-60 Gy: 0.05 vs. 0.04 (p = 0.100) and 0.82 vs. 0.85 (p = 0.616), respectively. The maximum dose of the spinal cord planning risk volume increased slightly (49.4 Gy vs. 47.9 Gy, p = 0.002). There was no significant difference in the mean doses to the heart and the thyroid gland. Prolongation of the delivery time was less than 1 min (5.6 min vs. 4.9 min, p = 0.010). The block plan for CEC could significantly reduce the lung dose, with acceptable increment in the spinal dose and a slightly prolonged delivery time.

Skin-sparing Helical Tomotherapy vs 3D-conformal Radiotherapy for Adjuvant Breast Radiotherapy: In Vivo Skin Dosimetry Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Capelle, Lisa; Warkentin, Heather; MacKenzie, Marc

Purpose: We investigated whether treatment-planning system (TPS)-calculated dose accurately reflects skin dose received for patients receiving adjuvant breast radiotherapy (RT) with standard three-dimensional conformal RT (3D-CRT) or skin-sparing helical tomotherapy (HT). Methods and Materials: Fifty patients enrolled in a randomized controlled trial investigating acute skin toxicity from adjuvant breast RT with 3D-CRT compared to skin-sparing HT, where a 5-mm strip of ipsilateral breast skin was spared. Thermoluminescent dosimetry or optically stimulated luminescence measurements were made in multiple locations and were compared to TPS-calculated doses. Skin dosimetric parameters and acute skin toxicity were recorded in these patients. Results: With HT theremore » was a significant correlation between calculated and measured dose in the medial and lateral ipsilateral breast (r = 0.67, P<.001; r = 0.44, P=.03, respectively) and the medial and central contralateral breast (r = 0.73, P<.001; r = 0.88, P<.001, respectively). With 3D-CRT there was a significant correlation in the medial and lateral ipsilateral breast (r = 0.45, P=.03; r = 0.68, P<.001, respectively); the medial and central contralateral breast (r = 0.62, P=.001; r = 0.86, P<.001, respectively); and the mid neck (r = 0.42, P=.04, respectively). On average, HT-calculated dose overestimated the measured dose by 14%; 3D-CRT underestimated the dose by 0.4%. There was a borderline association between highest measured skin dose and moist desquamation (P=.05). Skin-sparing HT had greater skin homogeneity (homogeneity index of 1.39 vs 1.65, respectively; P=.005) than 3D-CRT plans. HT plans had a lower skin{sub V50} (1.4% vs 5.9%, respectively; P=.001) but higher skin{sub V40} and skin{sub V30} (71.7% vs 64.0%, P=.02; and 99.0% vs 93.8%, P=.001, respectively) than 3D-CRT plans. Conclusion: The 3D-CRT TPS more accurately reflected skin dose than the HT TPS, which tended to overestimate dose received by 14% in patients receiving adjuvant breast RT.« less

SU-E-T-337: Dosimetric Study of TMI Using Helical Tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phurailatpam, R; Swamidas, J; Sastri, J

Purpose: The purpose of this study is to evaluate the dosimtry of TMI using Helical Tomotherapy (HT). Methods: Whole body CT data sets of 4 patients (median age : range:12–37 years) with 5mm slice thickness were used for planning in HT (TPS version 4.2.3). The contouring of the target and organ at risks (OAR) were delineated ( Oncentra Master Plan v 4.1). Two plans were generated using 5cm and 2.5 cm field widths.The modulation factor and pitch was 3 and 0.3 respectively. Dose to PTV, OARs and the dose homogeneity were evaluated. The doses obtained were compared with the existimgmore » literature. Dose delivery verification was carried out by point dose and 2D array measurements with ion chamber and Arc check dosimetry (Sun NuclearTM) system repectively. The prescribed dose was 14.4 Gy in 8 fractions. Results: The mean PTV volume was 7341.28cc (sd=2353) The dose homogeneity index of PTV was 12.03(sd=2.98) for 2.5cm-FW and 14.61 (sd=1.33) for 5cm-FW.The conformation number for 2.5 and 5 cm plans are 0.6328(sd=0.09) and 0.5915 (sd=0.0376) respectively. The mean dose(Gy) to the OARs were as follows for 2.5cm-FW : eyes, lens, lungs, kidneys, heart, liver,thyroid and testes for are 4.12,1.9,6.61,4.04,4.85,6.06,7.17 and 1.27. The mean dose(Gy) to the OARs were as follows for 5cm-FW :eyes, lens, lungs, kidneys, heart, liver,thyroid and testes for are 4.45,3.14,6.79,4.02,5.01,6.01,10.8 and 1.33. The mean variation of the point dose as compared to the expected dose was within 2% and the gamma analysis was at 91%. Conclusion: It was concluded that 5cm field width plans produces optimal dose volume parameters with deliverable treatment time. From this initial dissymmetric study, it was concluded that the treatment planning and the dose delivery verification was feasible considering the complexity of the TMI.« less

Out-of-field doses from pediatric craniospinal irradiations using 3D-CRT, IMRT, helical tomotherapy and electron-based therapy

NASA Astrophysics Data System (ADS)

De Saint-Hubert, Marijke; Verellen, Dirk; Poels, Kenneth; Crijns, Wouter; Magliona, Federica; Depuydt, Tom; Vanhavere, Filip; Struelens, Lara

2017-07-01

Medulloblastoma treatment involves irradiation of the entire central nervous system, i.e. craniospinal irradiation (CSI). This is associated with the significant exposure of large volumes of healthy tissue and there is growing concern regarding treatment-associated side effects. The current study compares out-of-field organ doses in children receiving CSI through 3D-conformal radiotherapy (3D-CRT), intensity modulated radiotherapy (IMRT), helical tomotherapy (HT) and an electron-based technique, and includes radiation doses resulting from imaging performed during treatment. An extensive phantom study is performed, using an anthropomorphic phantom corresponding to a five year old child, in which organ absorbed doses are measured using thermoluminescent detectors. Additionally, the study evaluates and explores tools for calculating out-of-field patient doses using the treatment planning system (TPS) and analytical models. In our study, 3D-CRT resulted in very high doses to a limited number of organs, while it was able to spare organs such as the lungs and breast when compared to IMRT and HT. Both IMRT and HT spread the dose over more organs and were able to spare the heart, thyroid, bladder, uterus and testes when compared to 3D-CRT. The electron-based technique considerably decreased the out-of-field doses in deep-seated organs but could not avoid nearby out-of-field organs such as the lungs, ribs, adrenals, kidneys and uterus. The daily imaging dose is small compared to the treatment dose burden. The TPS error for out-of-field doses was most pronounced for organs further away from the target; nevertheless, no systematic underestimation was observed for any of the studied TPS systems. Finally, analytical modeling was most optimal for 3D-CRT although the number of organs that could be modeled was limited. To conclude, none of the techniques studied was capable of sparing all organs from out-of-field doses. Nevertheless, the electron-based technique showed the most promise for out-of-field organ dose reduction during CSI when compared to photon techniques.

SU-F-T-457: A Filmless Method for Measurement of Couch Translation Per Gantry Rotation and Couch Speed for Tomotherapy Using ArcCheck

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, B; Wong, R; Geng, H

Purpose: To develop a filmless methodology based on an ArcCheck for QA measurement of the couch translation per gantry rotation and couch speed of a Tomotherapy unit. Methods: Two test plans recommended by TG148 were chosen for this study. A helical plan with 1 cm field size opened the leaves for 180 degrees at the 2nd, 7th and 12th of total 13 rotations and was used to verify if the couch travelled the expected distance per gantry rotation. The other test plan was a static plan with the gantry at 0°, 1cm field width and constant couch movement speed ofmore » 0.5mm/s. It was used for couch speed measurement. The ArcCheck was isocentrically set up and recorded movie files which took a snapshot exposure every 50ms. Due to the spiral pattern of diodes distribution, when one of the diodes of the ArcCheck located at the beam center, the dose profile as measured by the row of diodes which surrounded the center diode should have a symmetrical pattern. We divided the profile into left half A and right half B. Then a shape parameter was defined as S=Σ|(A−B)|/Σ(A+B). By searching the local minimum of S parameter, the beam center at different time could be located. The machine trajectory log data were also collected and analyzed for comparison. Results: The mean value of measured couch translation and couch speed by ArcCheck had less than 0.05% deviation from the planned values. For couch speed measurement, our result showed a mean value of 0.5002 with an uncertainty ±0.0031, which agreed very well with both the plan setting of 0.5 mm/s and the machine log data of 0.5005 mm/s. Conclusion: Couch translation measured using ArcCheck is accurate and comparable to the film-based measurement. This filmless method also provides a convenient and independent way for measuring couch speed.« less

Implementing a WIC-Based Intervention to Promote Exclusive Breastfeeding: Challenges, Facilitators, and Adaptive Strategies.

PubMed

Eldridge, Johanna D; Hartnett, Josette O; Lee, Furrina F; Sekhobo, Jackson P; Edmunds, Lynn S

Understand factors that contributed to the implementation of a successful multicomponent intervention to promote exclusive breastfeeding (EBF) within Special Supplemental Nutrition Program for Woman, Infants, and Children (WIC) clinics. Qualitative study of staff implementers' experiences using implementation status reports, facilitated group discussion immediately after implementation, and WIC administrative data. WIC staff from 12 clinics participated in an EBF Learning Community composed of 8 intervention trainings and ongoing support from trainers and peers. A total of 47 WIC staff including 11 directors, 20 other administrators, 8 nutritionists, and 6 peer counselors. A WIC-integrated EBF promotion initiative, supported through a Learning Community, composed of prenatal screening, tailored trimester-specific counseling, and timely postpartum follow-up. Challenges and facilitators to implementation within clinics. Iterative qualitative analysis using directed, emergent, and thematic coding. Implementation experiences were characterized by (1) perceived benefits of implementation, including improved EBF knowledge and counseling confidence among staff; and (2) managing implementation, including responding to challenges posed by clinic settings (resources, routine practices, values, and perceptions of mothers) through strategies such as adapting clinic practices and intervention components. Implementation was shaped by clinic setting and adaptive strategies. Future WIC interventions may benefit from formal consideration of intervention fit with local clinic setting and allowable adaptations. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

SU-E-J-189: Credentialing of IGRT Equipment and Processes for Clinical Trials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Court, L; Aristophanous, M; Followill, D

2014-06-01

Purpose: Current dosimetry phantoms used for clinical trial credentialing do not directly assess IGRT processes. This work evaluates a custom-built IGRT phantom for credentialing of multiple IGRT modalities and processes. Methods: An IGRT phantom was built out of a low-density body with two inserts. Insert A is used for the CT simulation. Insert B is used for the actual treatment. The inserts contain identical targets in different locations. Relative positions are unknown to the user. The user simulates the phantom (with insert A) as they would a patient, including marking the phantom. A treatment plan is created and sent tomore » the treatment unit. The phantom (with insert B) is then positioned using local IGRT practice. Shifts (planned isocenter, if applicable, and final isocenter) are marked on the phantom using room lasers. The mechanical reproducibility of re-inserting the inserts within the phantom body was tested using repeat high-resolution CT scans. The phantom was tested at 7 centers, selected to include a wide variety of imaging equipment. Results: Mechanical reproducibility was measured as 0.5-0.9mm, depending on the direction. Approaches tested to mark (and transfer) simulation isocenter included lasers, fiducials and reflective markers. IGRT approaches included kV imaging (Varian Trilogy, Brainlab ExacTrac), kV CT (CT-on-rails), kV CBCT (Varian Trilogy, Varian Truebeam, Elekta Agility) and MV CT (Tomotherapy). Users were able to successfully use this phantom for all combinations of equipment and processes. IGRT-based shifts agreed with the truth within 0.8mm, 0.8mm and 1.9mm in the LR, AP, and SI directions, respectively. Conclusion: Based on these preliminary results, the IGRT phantom can be used for credentialing of clinical trials with an action level of 1mm in AP and LR directions, and 2mm in the SI direction, consistent with TG142. We are currently testing with additional institutions with different equipment and processes, including Cyberknife. This project was funded by the Cancer Prevention Research Institute of Texas.« less

Multi-system verification of registrations for image-guided radiotherapy in clinical trials.

PubMed

Cui, Yunfeng; Galvin, James M; Straube, William L; Bosch, Walter R; Purdy, James A; Li, X Allen; Xiao, Ying

2011-09-01

To provide quantitative information on the image registration differences from multiple systems for image-guided radiotherapy (IGRT) credentialing and margin reduction in clinical trials. Images and IGRT shift results from three different treatment systems (Tomotherapy Hi-Art, Elekta Synergy, Varian Trilogy) have been sent from various institutions to the Image-Guided Therapy QA Center (ITC) for evaluation for the Radiation Therapy Oncology Group (RTOG) trials. Nine patient datasets (five head-and-neck and four prostate) were included in the comparison, with each patient having 1-4 daily individual IGRT studies. In all cases, daily shifts were re-calculated by re-registration of the planning CT with the daily IGRT data using three independent software systems (MIMvista, FocalSim, VelocityAI). Automatic fusion was used in all calculations. The results were compared with those submitted from institutions. Similar regions of interest (ROIs) and same initial positions were used in registrations for inter-system comparison. Different slice spacings for CBCT sampling and different ROIs for registration were used in some cases to observe the variation of registration due to these factors. For the 54 comparisons with head-and-neck datasets, the absolute values of differences of the registration results between different systems were 2.6±2.1 mm (mean±SD; range 0.1-8.6 mm, left-right [LR]), 1.7±1.3 mm (0.0-4.9 mm, superior-inferior [SI]), and 1.8±1.1 mm (0.1-4.0 mm, anterior-posterior [AP]). For the 66 comparisons in prostate cases, the differences were 1.1±1.0 mm (0.0-4.6 mm, LR), 2.1±1.7 mm (0.0-6.6 mm, SI), and 2.0±1.8 mm (0.1-6.9 mm, AP). The differences caused by the slice spacing variation were relatively small, and the different ROI selections in FocalSim and MIMvista also had limited impact. The extent of differences was reported when different systems were used for image registration. Careful examination and quality assurance of the image registration process are crucial before considering margin reduction using IGRT in clinical trials. Copyright © 2011 Elsevier Inc. All rights reserved.

SU-F-T-296: Modulated Therapy Down Under: A Survey of IMRT & VMAT Physics Practice in Australia and New Zealand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barber, J; School of Physics, University of Sydney; Vial, P

Purpose: A comprehensive survey of Australasian radiation oncology physics departments was undertaken to capture a snapshot of current usage, commissioning and QA practices for intensity-modulated therapies. Methods: An online survey was developed and advertised to Australian and New Zealand radiation oncology physicists through the local college (ACPSEM) in April 2015. The survey consisted of 147 questions in total, covering IMRT, VMAT and Tomotherapy, and details specific to different treatment planning systems. Questions captured detailed information on equipment, policies and procedures for the commissioning and QA of each treatment technique. Results: 41 partial or complete responses were collected, representing 59 departmentsmore » out of the 78 departments operational. 137 and 84 linacs from these departments were using IMRT and VMAT respectively, from a total 150 linacs. 100% and 78% of respondents were treating with IMRT and VMAT respectively. There are at least 8 different treatment planning systems being used for IMRT or VMAT, and large variations in all aspects of QA policies and procedures. 29 responses indicated 72 methods routinely used for pre-treatment QA, when breaking down by device and analysis type. Similar numbers of departments use field-by-field analysis compared to composite analysis (56% to 44%) while a majority use true gantry angle delivery compared to fixed gantry at 0° (72% to 28%). 19 different implementations of gamma index analysis parameters were reported from 33 responses. A follow-up one-day workshop to highlight the results, discuss the role of QA and share equipment-specific knowledge across users was conducted in November 2015. Conclusion: While IMRT and VMAT are almost universally available in Australasia, large variations in practice indicate a need for national or consensus guidelines.« less

Planned change or emergent change implementation approach and nurses' professional clinical autonomy.

PubMed

Luiking, Marie-Louise; Aarts, Leon; Bras, Leo; Grypdonck, Maria; van Linge, Roland

2017-11-01

Nurses' clinical autonomy is considered important for patients' outcome and influenced by the implementation approach of innovations. Emergent change approach with participation in the implementation process is thought to increase clinical autonomy. Planned change approach without this participation is thought not to increase clinical autonomy. Evidence of these effects on clinical autonomy is however limited. To examine the changes in clinical autonomy and in personal norms and values for a planned change and emergent change implementation of an innovation, e.g. intensive insulin therapy. Prospective comparative study with two geographically separated nurses' teams on one intensive care unit (ICU), randomly assigned to the experimental conditions. Data were collected from March 2008 to January 2009. Pre-existing differences in perception of team and innovation characteristics were excluded using instruments based on the innovation contingency model. The Nursing Activity Scale was used to measure clinical autonomy. The Personal Values and Norms instrument was used to assess orientation towards nursing activities and the Team Learning Processes instrument to assess learning as a team. Pre-implementation the measurements did not differ. Post-implementation, clinical autonomy was increased in the emergent change team and decreased in the planned change team. The Personal Values and Norms instrument showed in the emergent change team a decreased hierarchic score and increased developmental and rational scores. In the planned change team the hierarchical and group scores were increased. Learning as a team did not differ between the teams. In both teams there was a change in clinical autonomy and orientation towards nursing activities, in line with the experimental conditions. Emergent change implementation resulted in more clinical autonomy than planned change implementation. If an innovation requires the nurses to make their own clinical decisions, an emergent change implementation should help to establish this clinical autonomy. © 2015 British Association of Critical Care Nurses.

How GPs implement clinical guidelines in everyday clinical practice--a qualitative interview study.

PubMed

Le, Jette V; Hansen, Helle P; Riisgaard, Helle; Lykkegaard, Jesper; Nexøe, Jørgen; Bro, Flemming; Søndergaard, Jens

2015-12-01

Clinical guidelines are considered to be essential for improving quality and safety of health care. However, interventions to promote implementation of guidelines have demonstrated only partial effectiveness and the reasons for this apparent failure are not yet fully understood. To investigate how GPs implement clinical guidelines in everyday clinical practice and how implementation approaches differ between practices. Individual semi-structured open-ended interviews with seven GPs who were purposefully sampled with regard to gender, age and practice form. Interviews were recorded, transcribed verbatim and then analysed using systematic text condensation. Analysis of the interviews revealed three different approaches to the implementation of guidelines in clinical practice. In some practices the GPs prioritized time and resources on collective implementation activities and organized their everyday practice to support these activities. In other practices GPs discussed guidelines collectively but left the application up to the individual GP whilst others again saw no need for discussion or collective activities depending entirely on the individual GP's decision on whether and how to manage implementation. Approaches to implementation of clinical guidelines vary substantially between practices. Supporting activities should take this into account. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Research funders' roles and perceived responsibilities in relation to the implementation of clinical research results: a multiple case study of Swedish research funders.

PubMed

Brantnell, Anders; Baraldi, Enrico; van Achterberg, Theo; Winblad, Ulrika

2015-07-17

Implementation of clinical research results is challenging, yet the responsibility for implementation is seldom addressed. The process from research to the use of clinical research results in health care can be facilitated by research funders. In this paper, we report the roles of ten Swedish research funders in relation to implementation and their views on responsibilities in implementation. Ten cases were studied and compared using semi-structured interviews. In addition, websites and key documents were reviewed. Eight facilitative roles for research funders in relation to the implementation of clinical research results were identified. Three of them were common for several funders: "Advocacy work," "Monitoring implementation outcomes," and "Dissemination of knowledge." Moreover, the research funders identified six different actors responsible for implementation, five of which belonged to the healthcare setting. Collective and organizational responsibilities were the most common forms of responsibilities among the identified actors responsible for implementation. The roles commonly identified by the Swedish funders, "Advocacy work," "Monitoring implementation outcomes," and "Dissemination of knowledge," seem feasible facilitative roles in relation to the implementation of clinical research results. However, many actors identified as responsible for implementation together with the fact that collective and organizational responsibilities were the most common forms of responsibilities entail a risk of implementation becoming no one's responsibility.

A randomized matched-pairs study of feasibility, acceptability, and effectiveness of systems consultation: a novel implementation strategy for adopting clinical guidelines for Opioid prescribing in primary care.

PubMed

Quanbeck, Andrew; Brown, Randall T; Zgierska, Aleksandra E; Jacobson, Nora; Robinson, James M; Johnson, Roberta A; Deyo, Brienna M; Madden, Lynn; Tuan, Wen-Jan; Alagoz, Esra

2018-01-25

This paper reports on the feasibility, acceptability, and effectiveness of an innovative implementation strategy named "systems consultation" aimed at improving adherence to clinical guidelines for opioid prescribing in primary care. While clinical guidelines for opioid prescribing have been developed, they have not been widely implemented, even as opioid abuse reaches epidemic levels. We tested a blended implementation strategy consisting of several discrete implementation strategies, including audit and feedback, academic detailing, and external facilitation. The study compares four intervention clinics to four control clinics in a randomized matched-pairs design. Each systems consultant aided clinics on implementing the guidelines during a 6-month intervention consisting of monthly site visits and teleconferences/videoconferences. The mixed-methods evaluation employs the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework. Quantitative outcomes are compared using time series analysis. Qualitative methods included focus groups, structured interviews, and ethnographic field techniques. Seven clinics were randomly approached to recruit four intervention clinics. Each clinic designated a project team consisting of six to eight staff members, each with at least one prescriber. Attendance at intervention meetings was 83%. More than 80% of staff respondents agreed or strongly agreed with the statements: "I am more familiar with guidelines for safe opioid prescribing" and "My clinic's workflow for opioid prescribing is easier." At 6 months, statistically significant improvements were noted in intervention clinics in the percentage of patients with mental health screens, treatment agreements, urine drug tests, and opioid-benzodiazepine co-prescribing. At 12 months, morphine-equivalent daily dose was significantly reduced in intervention clinics compared to controls. The cost to deliver the strategy was $7345 per clinic. Adaptations were required to make the strategy more acceptable for primary care. Qualitatively, intervention clinics reported that chronic pain was now treated using approaches similar to those employed for other chronic conditions, such as hypertension and diabetes. The systems consultation implementation strategy demonstrated feasibility, acceptability, and effectiveness in a study involving eight primary care clinics. This multi-disciplinary strategy holds potential to mitigate the prevalence of opioid addiction and ultimately may help to improve implementation of clinical guidelines across healthcare. ClinicalTrials.gov (NCT02433496). https://clinicaltrials.gov/ct2/show/NCT02433496 Registered May 5, 2015.

SU-F-J-181: An Alternative Patient Alignment Tool On TomoTherapy: The First In- Human Megavoltage-Topogram Acquisition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, L; Low, D; Lee, P

Purpose: To show the first in-human Megavoltage (MV)-Topogram acquisition for the evaluation of the potential for MV-Topogram-based alignment as an alternative to MVCT for reducing dose and imaging time. Methods: A lung cancer patient was enrolled in an ongoing IRB-approved clinical trial at our institute. The patient was set up using the clinical protocol employing positioning lasers. 3.2mm diameter tungsten spheres were placed on the patient’s skin at their alignment tattoos to check surface-based marker concordance between topograms and MVCT. Anterior-Posterior (AP) and lateral (LAT) MV-Topograms were acquired using gantry angles of 0°/90° with a 1mm collimator opening, all MLCmore » leafs open, 4cm/s couch speed, and 12.5s scanning time. The topogram acquisition was immediately followed by the normal MVCT scan acquisition. MV-Topograms were reconstructed from the detector exit-data using in-house developed software. The topograms were also enhanced using contrast-limited adaptive histogram equalization (CLAHE). The MV-Topograms were registered to reference kV-based digitally reconstructed topograms. The localization results were compared against results obtained comparing the clinical MVCT to the kVCT simulation. Results: The shifts using the unenhanced Topograms, enhanced Topograms, and MVCT were (LAT, LONG, VERT, ROLL) (5.8mm, 2.6mm, −5.6mm, 0.34°), (3.9mm, 2.5mm, −2.2mm, 0.65°) and (2.4mm, 1.5mm, −3.0mm, 0.5°), respectively. The magnitude alignment differences between the enhanced Topograms and MVCT were within 1.5 mm and 0.15°. The average MVCT and total Topogram acquisition times were 272.9s ± 31.5s and 46s, respectively. Conclusion: MV-Topograms have the potential for providing equivalent performance with less dose and acquisition time than the traditional MVCT technique. We are evaluating other sites as well as adding patients to develop statistically significant analyses regarding the alignment quality differences. MV-Topograms are likely to be most clinically useful for bony anatomy and radiopaque marker-based alignments. The study was supported by an Accuray Grant.« less

Implementing clinical guidelines to prevent catheter-associated urinary tract infections and improve catheter care in nursing homes: Systematic review.

PubMed

Gould, Dinah; Gaze, Sarah; Drey, Nicholas; Cooper, Tracey

2017-05-01

Catheter-associated urinary tract infection is the most common health care-associated infection, is considered avoidable, and has cost implications for health services. Prevalence is high in nursing homes, but little research has been undertaken to establish whether implementing clinical guidelines can reduce infection rates in long-term care or improve quality of urinary catheter care. Systematic search and critical appraisal of the literature. Three studies evaluated the impact of implementing a complete clinical guideline. Five additional studies evaluated the impact of implementing individual elements of a clinical guideline. Prevention of catheter-associated urinary tract infection in nursing homes has received little clinical or research attention. Studies concerned with whole guideline implementation emerged as methodologically poor using recognized criteria for critically appraising epidemiologic studies concerned with infection prevention. Research evaluating the impact of single elements of clinical guidelines is more robust, and their findings could be implemented to prevent urinary infections in nursing homes. Copyright © 2017. Published by Elsevier Inc.

The role of clinical governance as a strategy for quality improvement in primary care.

PubMed Central

Campbell, Stephen M; Sweeney, Grace M

2002-01-01

This power considers the process of implementing clinical governance in primary care and its impact on quality improvement. It discuss how clinical governance is being implemented both at the level of Primary Care Organisations and general practices, and the challenges to implementing clinical governance. It also suggests a model for promoting the factors that will help clinical governance improve quality of care. The experience of implementing clinical governance is broadly positive to date. However, the government needs to match its commitment to a ten-year programme of change with realistic timetables to secure the cultural and organisational changes needed to improve quality of care. PMID:12389764

Measuring performance to drive improvement: development of a clinical indicator set for general medicine.

PubMed

Brand, C; Lam, S K L; Roberts, C; Gorelik, A; Amatya, B; Smallwood, D; Russell, D

2009-06-01

There are delays in implementing evidence about effective therapy into clinical practice. Clinical indicators may support implementation of guideline recommendations. To develop and evaluate the short-term impact of a clinical indicator set for general medicine. A set of clinical process indicators was developed using a structured process. The indicator set was implemented between January 2006 and December 2006, using strategies based on evidence about effectiveness and local contextual factors. Evaluation included a structured survey of general medical staff to assess awareness and attitudes towards the programme and qualitative assessment of barriers to implementation. Impact on documentation of adherence to clinical indicators was assessed by auditing a random sample of medical records before (2003-2005) and after (2006) implementation. Clinical indicators were developed for the following areas: venous thromboembolism, cognition, chronic heart failure, chronic obstructive pulmonary disease, diabetes, low trauma fracture, patient written care plans. The programme was well supported and incurred little burden to staff. Implementation occurred largely as planned; however, documentation of adherence to clinical indicators was variable. There was a generally positive trend over time, but for most indicators this was independent of the implementation process and may have been influenced by other system improvement activities. Failure to demonstrate a significant impact during the pilot phase is likely to have been influenced by administrative factors, especially lack of an integrative data documentation and collection process. Successful implementation in phase two is likely to depend upon an effective data collection system integrated into usual care.

Evidence and resources to implement Pharmacogenetic Knowledge for Precision Medicine

PubMed Central

Caudle, Kelly E.; Gammal, Roseann S.; Whirl-Carrillo, Michelle; Hoffman, James M.; Relling, Mary V.; Klein, Teri E.

2016-01-01

Purpose Implementation of pharmacogenetics into clinical practice has been relatively slow despite substantial scientific progress over the last decade. One barrier that inhibits uptake of pharmacogenetics into routine clinical practice is the lack of knowledge of how to translate a genetic test into a clinical action based on current evidence. The purpose of this paper is to describe the current state of pharmacogenetic evidence and evidence-based resources that facilitate the uptake of pharmacogenetics into clinical practice. Summary Controversy exists over the required evidence threshold needed for routine clinical implementation of pharmacogenetics. Large randomized controlled trials are not clinically feasible or necessary for many pharmacogenetic applications. Online resources exist like the Clinical Pharmacogenetics Implementation Consortium (CPIC) and the Pharmacogenomics Knowledgebase (PharmGKB) that provide freely available, evidence-based resources that facilitate the translation of genetic laboratory test results into actionable prescribing recommendations for specific drugs. Conclusion Resources provided by organizations such as CPIC and PharmGKB that use standardized approaches to evaluate the literature and provide clinical guidance are essential for the implementation of pharmacogenetics into routine clinical practice. PMID:27864205

Approved Clinical Instructors' Perspectives on Implementation Strategies in Evidence-Based Practice for Athletic Training Students

PubMed Central

Hankemeier, Dorice A.; Van Lunen, Bonnie L.

2011-01-01

Context: Understanding implementation strategies of Approved Clinical Instructors (ACIs) who use evidence-based practice (EBP) in clinical instruction will help promote the use of EBP in clinical practice. Objective: To examine the perspectives and experiences of ACIs using EBP concepts in undergraduate athletic training education programs to determine the importance of using these concepts in clinical practice, clinical EBP implementation strategies for students, and challenges of implementing EBP into clinical practice while mentoring and teaching their students. Design: Qualitative study. Setting: Telephone interviews. Patients or Other Participants: Sixteen ACIs (11 men, 5 women; experience as a certified athletic trainer = 10 ± 4.7 years, experience as an ACI = 6.8 ± 3.9 years) were interviewed. Data Collection and Analysis: We interviewed each participant by telephone. Interview transcripts were analyzed and coded for common themes and subthemes regarding implementation strategies. Established themes were triangulated through peer review and member checking to verify the data. Results: The ACIs identified EBP implementation as important for validation of the profession, changing paradigm shift, improving patient care, and improving student educational experiences. They promoted 3 methods of implementing EBP concepts with their students: self-discovery, promoting critical thinking, and sharing information. They assisted students with the steps of EBP and often faced challenges in implementation of the first 3 steps of EBP: defining a clinical question, literature searching, and literature appraisal. Finally, ACIs indicated that modeling the behavior of making clinical decisions based on evidence was the best way to encourage students to continue using EBP. Conclusions: Athletic training education program directors should encourage and recommend specific techniques for EBP implementation in the clinical setting. The ACIs believed that role modeling is a strategy that can be used to promote the use of EBP with students. Training of ACIs should include methods by which to address the steps of the EBP process while still promoting critical thinking. PMID:22488192

Reaching out to clinicians: implementation of a computerized alert system.

PubMed

Degnan, Dan; Merryfield, Dave; Hultgren, Steve

2004-01-01

Several published articles have identified that providing automated, computer-generated clinical alerts about potentially critical clinical situations should result in better quality of care. In 1999, the pharmacy department at a community hospital network implemented and refined a commercially available, computerized clinical alert system. This case report discusses the implementation process, gives examples of how the system is used, and describes results following implementation. The use of the clinical alert system in this hospital network resulted in improved patient safety as well as in greater efficiency and decreased costs.

The effectiveness of clinical supervision for a group of ward managers based in a district general hospital: an evaluative study.

PubMed

Davis, Cynthia; Burke, Linda

2012-09-01

To present an evaluative audit assessing the effectiveness of clinical supervision for ward managers. A year-long project to introduce clinical supervision to ward managers was implemented and evaluated. The objectives were to evaluate staff perceptions of implementing clinical supervision and determine its outcomes. An audit evaluation process was used. Findings are presented against perceptions, implementation and reported outcomes of clinical supervision. Insights were gained into its relevance and importance to nurses and the organisation. Findings show that clinical supervision was perceived to be effective and helped improve patient care, but some feared it becoming a form of managerial control. Ward managers perceived advantages for personal and professional development from adopting this process. There is a need for greater understanding of clinical supervision before Trusts implement it. The introduction of a resource pack for clinical areas would also be of value. Finally, there needs to be a named person who has a special knowledge of clinical supervision to act as a champion and change agent in effecting implementation at both the executive level and within each clinical area. © 2011 Blackwell Publishing Ltd.

Clinical Practice Guideline Implementation Strategy Patterns in Veterans Affairs Primary Care Clinics

PubMed Central

Hysong, Sylvia J; Best, Richard G; Pugh, Jacqueline A

2007-01-01

Background The Department of Veterans Affairs (VA) mandated the system-wide implementation of clinical practice guidelines (CPGs) in the mid-1990s, arming all facilities with basic resources to facilitate implementation; despite this resource allocation, significant variability still exists across VA facilities in implementation success. Objective This study compares CPG implementation strategy patterns used by high and low performing primary care clinics in the VA. Research Design Descriptive, cross-sectional study of a purposeful sample of six Veterans Affairs Medical Centers (VAMCs) with high and low performance on six CPGs. Subjects One hundred and two employees (management, quality improvement, clinic personnel) involved with guideline implementation at each VAMC primary care clinic. Measures Participants reported specific strategies used by their facility to implement guidelines in 1-hour semi-structured interviews. Facilities were classified as high or low performers based on their guideline adherence scores calculated through independently conducted chart reviews. Findings High performing facilities (HPFs) (a) invested significantly in the implementation of the electronic medical record and locally adapting it to provider needs, (b) invested dedicated resources to guideline-related initiatives, and (c) exhibited a clear direction in their strategy choices. Low performing facilities exhibited (a) earlier stages of development for their electronic medical record, (b) reliance on preexisting resources for guideline implementation, with little local adaptation, and (c) no clear direction in their strategy choices. Conclusion A multifaceted, yet targeted, strategic approach to guideline implementation emphasizing dedicated resources and local adaptation may result in more successful implementation and higher guideline adherence than relying on standardized resources and taxing preexisting channels. PMID:17355583

Intensity-modulated radiotherapy (IMRT) for carcinoma of the maxillary sinus: A comparison of IMRT planning systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ahmed, Raef S.; Ove, Roger; Duan, Jun

2006-10-01

The treatment of maxillary sinus carcinoma with forward planning can be technically difficult when the neck also requires radiotherapy. This difficulty arises because of the need to spare the contralateral face while treating the bilateral neck. There is considerable potential for error in clinical setup and treatment delivery. We evaluated intensity-modulated radiotherapy (IMRT) as an improvement on forward planning, and compared several inverse planning IMRT platforms. A composite dose-volume histogram (DVH) was generated from a complex forward planned case. We compared the results with those generated by sliding window fixed field dynamic multileaf collimator (MLC) IMRT, using sets of coplanarmore » beams. All setups included an anterior posterior (AP) beam, and 3-, 5-, 7-, and 9-field configurations were evaluated. The dose prescription and objective function priorities were invariant. We also evaluated 2 commercial tomotherapy IMRT delivery platforms. DVH results from all of the IMRT approaches compared favorably with the forward plan. Results for the various inverse planning approaches varied considerably across platforms, despite an attempt to prescribe the therapy similarly. The improvement seen with the addition of beams in the fixed beam sliding window case was modest. IMRT is an effective means of delivering radiotherapy reliably in the complex setting of maxillary sinus carcinoma with neck irradiation. Differences in objective function definition and optimization algorithms can lead to unexpected differences in the final dose distribution, and our evaluation suggests that these factors are more significant than the beam arrangement or number of beams.« less

Intensity-modulated radiation therapy (IMRT) with different combinations of treatment-planning systems and linacs: issues and how to detect them.

PubMed

Dobler, Barbara; Lorenz, Friedlieb; Wertz, Hansjörg; Polednik, Martin; Wolff, Dirk; Steil, Volker; Lohr, Frank; Wenz, Frederik

2006-08-01

To compare different combinations of intensity-modulated radiation therapy (IMRT) system components with regard to quality assurance (QA), especially robustness against malfunctions and dosimetry. Three different treatment-planning systems (TPS), two types of linacs and three multileaf collimator (MLC) types were compared: commissioning procedures were performed for the combination of the TPS Corvus 5.0 (Nomos) and KonRad v2.1.3 (Siemens OCS) with the linacs KD2 (Siemens) and Synergy (Elekta). For PrecisePLAN 2.03 (Elekta) measurements were performed for Elekta Synergy only. As record and verify (R&V) system Multi-Access v7 (IMPAC) was used. The use of the serial tomotherapy system Peacock (Nomos) was investigated in combination with the Siemens KD2 linac. In the comparison of calculated to measured dose, problems were encountered for the combination of KonRad and Elekta MLC as well as for the Peacock system. Multi-Access failed to assign the collimator angle correctly for plans with multiple collimator angles per beam. Communication problems of Multi-Access with both linacs were observed, resulting in incorrect recording of the treatment. All reported issues were addressed by the manufacturers. For the commissioning of IMRT systems, the whole chain from the TPS to the linac has to be investigated. Components that passed the commissioning in another clinical environment can have severe malfunctions when used in a new environment. Therefore, not only single components but the whole chain from planning to delivery has to be evaluated in commissioning and checked regularly for QA.

Implementation of Patient Decision Support Interventions in Primary Care: The Role of Relational Coordination.

PubMed

Tietbohl, Caroline K; Rendle, Katharine A S; Halley, Meghan C; May, Suepattra G; Lin, Grace A; Frosch, Dominick L

2015-11-01

The benefits of patient decision support interventions (DESIs) have been well documented. However, DESIs remain difficult to incorporate into clinical practice. Relational coordination (RC) has been shown to improve performance and quality of care in health care settings. This study aims to demonstrate how applying RC theory to DESI implementation could elucidate underlying issues limiting widespread uptake. Five primary care clinics in Northern California participated in a DESI implementation project. We used a deductive thematic approach guided by behaviors outlined in RC theory to analyze qualitative data collected from ethnographic field notes documenting the implementation process and focus groups with health care professionals. We then systematically compared the qualitative findings with quantitative DESI distribution data. Based on DESI distribution rates, clinics were placed into 3 performance categories: high, middle, and low. Qualitative data illustrated how each clinic's performance related to RC behaviors. Consistent with RC theory, the high-performing clinic exhibited frequent, timely, and accurate communication and positive working relationships. The 3 middle-performing clinics exhibited high-quality communication within physician-staff teams but limited communication regarding DESI implementation across the clinic. The lowest-performing clinic was characterized by contentious relationships and inadequate communication. Limitations of the study include nonrandom selection of clinics and limited geographic diversity. In addition, ethnographic data collected documented only DESI implementation practices and not larger staff interactions contributing to RC. These findings suggest that a high level of RC within clinical settings may be a key component and facilitator of successful DESI implementation. Future attempts to integrate DESIs into clinical practice should consider incorporating interventions designed to increase positive RC behaviors as a potential means to improve uptake. © The Author(s) 2015.

Evaluation and implementation of highly challenging balance training in clinical practice for people with Parkinson's disease: protocol for the HiBalance effectiveness-implementation trial.

PubMed

Leavy, Breiffni; Kwak, Lydia; Hagströmer, Maria; Franzén, Erika

2017-02-07

If people with progressive neurological diseases are to avail of evidence-based rehabilitation, programs found effective in randomized controlled trials (RCT's) must firstly be adapted and tested in clinical effectiveness studies as a means of strengthening their evidence base. This paper describes the protocol for an effectiveness-implementation trial that will assess the clinical effectiveness of a highly challenging balance training program (the HiBalance program) for people with mild-moderate Parkinson's disease (PD) while simultaneously collecting data concerning the way in which the program is implemented. The HiBalance program is systemically designed to target balance impairments in PD and has been shown effective at improving balance control and gait in a previous RCT. Study aims are to i) determine the effectiveness of the adapted HiBalance program on performance and self-rated outcomes such as balance control, gait and physical activity level ii) conduct a process evaluation of program implementation at the various clinics iii) determine barriers and facilitators to program implementation in these settings. This effectiveness-implementation type 1 hybrid study will use a non-randomized controlled design with consecutive inclusion of people with PD at multiple clinical sites. A mixed method approach will be used to collect clinical effectiveness data and process evaluation data which is both quantitative and qualitative in nature. The consolidated framework for implementation research (CFIR) will be used to guide the planning and collection of data concerning implementation barriers and facilitators. The HiBalance program will be provided by physical therapists as a part of standard rehabilitation care at the clinical sites, while the evaluation of the implementation process will be performed by the research group and funded by research grants. An effectiveness-implementation study design benefits patients by speeding up the process of translating findings from research settings to routine health care. Findings from this study will also be highly relevant for those working with neurological rehabilitation when faced with decisions concerning the translation of training programs from efficacy studies to everyday clinical practice. ClinicalTrials.gov march 2016, NCT02727478 .

Clinical Implementation of Pharmacogenomics for Personalized Precision Medicine: Barriers and Solutions.

PubMed

Klein, Michelle E; Parvez, Md Masud; Shin, Jae-Gook

2017-09-01

Clinical implementation of pharmacogenomics (PGx) leads to personalized medicine, which improves the efficacy, safety, and cost-effectiveness of treatments. Although PGx-based research has been conducted for more than a decade, several barriers have slowed down its widespread implementation in clinical practice. Globally, there is an imbalance in programs and solutions required to empower the clinical implementation of PGx between countries. Therefore, we aimed to review these issues comprehensively, determine the major barriers, and find the best solutions. Through an extensive review of ongoing clinical implementation programs, scientific, educational, ethical, legal, and social issues, information technology, and reimbursement were identified as the key barriers. The pace of global implementation of genomic medicine coincided with the resource limitations of each country. The key solutions identified for the earlier mentioned barriers are as follows: building of secure and suitable information technology infrastructure with integrated clinical decision support systems along with increasing PGx evidence, more regulations, reimbursement strategies for stakeholder's acceptance, incorporation of PGx education in all institutions and clinics, and PGx promotion to all health care professionals and patients. In conclusion, this review will be helpful for the better understanding of common barriers and solutions pertaining to the clinical application of PGx. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Establishing support groups for HIV-infected women: using experiences to develop guiding principles for project implementation.

PubMed

Visser, Maretha J; Mundell, Jonathan P

2008-07-01

HIV-infected women need support to deal with their diagnosis as well as with the stigma attached to HIV. As part of their practical training, Master's-level psychology students negotiated with the staff of four clinics in townships in Tshwane, South Africa, to establish support groups for HIV+ women and offered to assist them in facilitating the groups. This study aimed to understand why the implementation of groups was successful in one clinic and not other clinics. The student reports on their experiences and interaction with clinic staff and clients were used as sources of data. Using qualitative data analysis, different dynamics and factors that could affect project implementation were identified in each clinic. The socio-ecological and systems theories were used to understand implementation processes and obstacles in implementation. The metaphor of building a bridge over a gorge was used to describe the different phases in and obstacles to the implementation of the intervention. Valuable lessons were learnt, resulting in the development of guiding principles for the implementation of support groups in community settings.

WE-C-TOUR-T-00: Exhibit Hall Guided Tours-Microdosimeters for Therapy (Wednesday) WE-C-TOUR-T-01

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Tour Leader: Indra Das, NYU Langone Medical Center, New York, NY Tour Guides: Hsui Ai, Indiana University School of Medicine, Indianapolis, IN Paulina Galvis, NYU Langone Medical Center, New York, NY Olga Volotoskova, NYU Langone Medical Center, New York, NY Participating Vendors: IBA PTW – New York RTI Electronics, Inc. Standard Imaging, Inc. Sun Nuclear Corporation Small fields are increasing used in specialized radiation treatments such as Gammaknife, Cyberknife, Tomotherapy, IMRT, VMAT, SRS and SBRT. Due to small field size electron transport creates lateral electronic disequilibrium and thus dosimetry could be very difficult. Microdetectors are used for small field dosimetrymore » which will be discussed in preface of this tour as below: Understanding small field e.g. meaning and definition of small field IAEA definition and approach Characteristics of microdetectors in terms of perturbation, recombination, correction Suitability of microdetectors in small field dosimetry.« less

WE-C-TOUR-T-01: Microdosimeters for Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Das, I.

Tour Leader: Indra Das, NYU Langone Medical Center, New York, NY Tour Guides: Hsui Ai, Indiana University School of Medicine, Indianapolis, IN Paulina Galvis, NYU Langone Medical Center, New York, NY Olga Volotoskova, NYU Langone Medical Center, New York, NY Participating Vendors: IBA PTW – New York RTI Electronics, Inc. Standard Imaging, Inc. Sun Nuclear Corporation Small fields are increasing used in specialized radiation treatments such as Gammaknife, Cyberknife, Tomotherapy, IMRT, VMAT, SRS and SBRT. Due to small field size electron transport creates lateral electronic disequilibrium and thus dosimetry could be very difficult. Microdetectors are used for small field dosimetrymore » which will be discussed in preface of this tour as below: Understanding small field e.g. meaning and definition of small field IAEA definition and approach Characteristics of microdetectors in terms of perturbation, recombination, correction Suitability of microdetectors in small field dosimetry.« less

TU-E-TOUR-T-00: Exhibit Hall Guided Tours-Microdosimeters for Therapy (Tuesday)

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Tour Leader: Indra Das, NYU Langone Medical Center, New York, NY Tour Guides: Hsui Ai, Indiana University School of Medicine, Indianapolis, IN Aaron Andersen, Indiana University School of Medicine, Indianapolis, IN Olga Volotoskova, NYU Langone Medical Center, New York, NY Participating Vendors: IBA PTW – New York RTI Electronics, Inc. Standard Imaging, Inc. Sun Nuclear Corporation Small fields are increasing used in specialized radiation treatments such as Gammaknife, Cyberknife, Tomotherapy, IMRT, VMAT, SRS and SBRT. Due to small field size electron transport creates lateral electronic disequilibrium and thus dosimetry could be very difficult. Microdetectors are used for small field dosimetrymore » which will be discussed in preface of this tour as below: Understanding small field e.g. meaning and definition of small field IAEA definition and approach Characteristics of microdetectors in terms of perturbation, recombination, correction Suitability of microdetectors in small field dosimetry.« less

Technical experiences of implementing a wireless tracking and facial biometric verification system for a clinical environment

NASA Astrophysics Data System (ADS)

Liu, Brent; Lee, Jasper; Documet, Jorge; Guo, Bing; King, Nelson; Huang, H. K.

2006-03-01

By implementing a tracking and verification system, clinical facilities can effectively monitor workflow and heighten information security in today's growing demand towards digital imaging informatics. This paper presents the technical design and implementation experiences encountered during the development of a Location Tracking and Verification System (LTVS) for a clinical environment. LTVS integrates facial biometrics with wireless tracking so that administrators can manage and monitor patient and staff through a web-based application. Implementation challenges fall into three main areas: 1) Development and Integration, 2) Calibration and Optimization of Wi-Fi Tracking System, and 3) Clinical Implementation. An initial prototype LTVS has been implemented within USC's Healthcare Consultation Center II Outpatient Facility, which currently has a fully digital imaging department environment with integrated HIS/RIS/PACS/VR (Voice Recognition).

Clinical Guidelines and Implementation into Daily Dental Practice.

PubMed

Guncu, Guliz Nigar; Nemli, Secil Karakoca; Carrilho, Eunice; Yamalık, Nermin; Volodina, Elena; Melo, Paulo; Margvelashvili, Vladimer; Rossi, Alessandra

2018-01-31

The purpose of this study is to assess the extent of the familiarity, attitude and perceptions of dental professionals regarding clinical dental guidelines and their implementation into daily dental practice. For this purpose, a questionnaire which was developed by the members of the World Dental Federation, European Regional Organization Working Group - 'Relation Between Dental Practitioner and Universities', was implemented by the National Dental Associations of six European Regional Organization-zone countries (Georgian Stomatological Association - Georgia, Associazione Nazionale Dentisti Italiani - Italy, Portuguese Dental Association - Portugal, Russian Dental Association - Russia, Swiss Dental Association - Switzerland, and Turkish Dental Association - Turkey. The questionnaire was filled by a total of 910 dental professionals who are members of one of these national dental associations and who voluntarily wanted to participate to this survey. Most of the survey participants were familiar with clinical dental guidelines (68%), claimed that they implemented them into daily practice (61.7%), and generally acknowledged their benefits (81.8%). Many participants believed that clinical dental guidelines could help to improve the clinical treatment plan (50.6 %) and the accuracy of diagnosis (39.4%); which increased with age and years of practice (p < 0.05). The most frequently perceived barrier to the effective implementation of clinical dental guidelines was expressed as 'lack of awareness', while participants suggested a role for national dental associations in spreading clinical dental guidelines. A better understanding of the perceptions and attitudes of dentists towards clinical dental guidelines and the potential impact of factors affecting such perceptions and attitudes may be of particular importance for attempts aiming at overcoming the barriers for effective implementation of clinical dental guidelines into daily practice. Despite a significant familiarity and a common positive attitude, dental professionals are likely to have different perceptions towards clinical dental guidelines, especially regarding their effective implementation into daily practice, benefits and barriers.

Creation of an atlas of filter positions for fluence field modulated CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szczykutowicz, Timothy P., E-mail: TSzczykutowicz@uwhealth.org; Hermus, James

2015-04-15

Purpose: Fluence field modulated CT (FFMCT) and volume of interest (VOI) CT imaging applications require adjustment of the profile of the x-ray fluence incident on a patient as a function of view angle. Since current FFMCT prototypes can theoretically take on an infinite number of configurations, measuring a calibration data set for all possible positions would not be feasible. The present work details a methodology for calculating an atlas of configurations that will span all likely body regions, patient sizes, patient positioning, and imaging modes. The hypothesis is that there exists a finite number of unique modulator configurations that effectivelymore » span the infinite number of possible fluence profiles with minimal loss in performance. Methods: CT images of a head, shoulder, thorax, abdominal, wrist, and leg anatomical slices were dilated and contracted to model small, medium, and large sized patients. Additionally, the images were positioned from iso-center by three different amounts. The modulator configurations required to compensate for each image were computed assuming a FFMCT prototype, digital beam attenuator, (DBA), was set to equalize the detector exposure. Each atlas configuration should be different from the other atlas configurations. The degree of difference was quantified using the sum of the absolute differences in filter thickness between configurations. Using this metric, a set of unique wedge configurations for which no two configurations have a metric value smaller than some threshold can be constructed. Differences in the total number of incident photons between the unconstrained filters and the atlas were studied as a function of the number of atlas positions for each anatomical site and size/off-centering combination. Results: By varying the threshold used in creating the atlas, it was found that roughly 322 atlas positions provided an incident number of photons within 20% of using 19 440 unique filters (the number of atlas entries ranged from 7213 to 1). Additionally, for VOI applications implemented with a single VOI region, the number of required filter configurations was expressed in a simple closed form solution. Conclusions: The methodology proposed in this work will enable DBA-FFMCT and DBA-VOI imaging in the clinic without the need for patient specific air-scans to be performed. In addition, the methodology proposed here is directly applicable to other modulator designs such as piecewise linear, TomoTherapy multi leaf collimators, 2D fluid arrays, and inverse geometry CT.« less

Clinical Chemistry of Patients With Ebola in Monrovia, Liberia

PubMed Central

de Wit, Emmie; Kramer, Shelby; Prescott, Joseph; Rosenke, Kyle; Falzarano, Darryl; Marzi, Andrea; Fischer, Robert J.; Safronetz, David; Hoenen, Thomas; Groseth, Allison; van Doremalen, Neeltje; Bushmaker, Trenton; McNally, Kristin L.; Feldmann, Friederike; Williamson, Brandi N.; Best, Sonja M.; Ebihara, Hideki; Damiani, Igor A. C.; Adamson, Brett; Zoon, Kathryn C.; Nyenswah, Tolbert G.; Bolay, Fatorma K.; Massaquoi, Moses; Sprecher, Armand; Feldmann, Heinz; Munster, Vincent J.

2016-01-01

The development of point-of-care clinical chemistry analyzers has enabled the implementation of these ancillary tests in field laboratories in resource-limited outbreak areas. The Eternal Love Winning Africa (ELWA) outbreak diagnostic laboratory, established in Monrovia, Liberia, to provide Ebola virus and Plasmodium spp. diagnostics during the Ebola epidemic, implemented clinical chemistry analyzers in December 2014. Clinical chemistry testing was performed for 68 patients in triage, including 12 patients infected with Ebola virus and 18 infected with Plasmodium spp. The main distinguishing feature in clinical chemistry of Ebola virus–infected patients was the elevation in alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyltransferase levels and the decrease in calcium. The implementation of clinical chemistry is probably most helpful when the medical supportive care implemented at the Ebola treatment unit allows for correction of biochemistry derangements and on-site clinical chemistry analyzers can be used to monitor electrolyte balance. PMID:27471319

Implementation of national comprehensive cancer network evidence-based guidelines to prevent and treat cancer-related infections.

PubMed

Wood, Sylvia K; Payne, Judith K

2012-06-01

Clinical practice guidelines are an important result of evidence-based research. However, current clinical practice remains out of step with the rapid pace of research advancements. Often, decades pass before research is translated into clinical practice. The National Comprehensive Cancer Network (NCCN) has created evidence-based clinical guidelines to promote effective clinical practice. Formerly, the NCCN established guidelines to reduce cancer-related infections only for neutropenic patients; however, they have expanded their guidelines beyond neutropenia to prevent and treat cancer-related infections. Implementing scientific evidence into clinical practice is challenging and complex, and healthcare professionals should understand barriers to implementing clinical practice guidelines to ensure successful translation into practice. This article provides a brief review of NCCN guidelines and describes common barriers encountered during implementation. In addition, a conceptual framework is offered to help identify and address potential concerns before and after adoption of guidelines.

Out of sight, out of mind? Does terminating the physical presence of a geriatric consultant in the community clinic reduce the implementation rate for geriatric recommendations.

PubMed

Freud, Tamar; Punchik, Boris; Biderman, Aya; Peleg, Roni; Kagan, Ella; Barzak, Alex; Press, Yan

2016-01-01

To assess the effect of moving the geriatric consultation from the primary care clinic to another setting, on the rate of implementation of geriatric recommendations by family physicians. A retrospective review of the computerized medical records of elderly patients in four primary care clinics. The rate of implementation of geriatric recommendations was compared between clinics in which a geriatric consultant was physically present (control clinics) and a clinic where the consultation took place elsewhere (study clinic). In addition, the results of the present study were compared to a previous study in which the geriatric consultation was carried out in the study clinic and the family doctor was an active participant. 127 computerized files were reviewed in the study clinic and 133 in the control clinics. The mean age of the patients was 81.1±6.3 years and 63.1% were women. The overall implementation of geriatric recommendations by family doctors in the study clinic was 55.9%, a statistically significant decrease compared to the previous study where the rate was 73.9% (p<0.0001). In contrast, there was no change in the implementation rate in the control clinics at 65.0% in the present study and 59.9% in the previous one (p=0.205). Direct, person-to-person contact between the geriatric consultant and the family doctor has a beneficial effect on the implementation of geriatric recommendations. This should be considered by healthcare policy makers when planning geriatric services in the community. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Implementation of quality management for clinical bacteriology in low-resource settings.

PubMed

Barbé, B; Yansouni, C P; Affolabi, D; Jacobs, J

2017-07-01

The declining trend of malaria and the recent prioritization of containment of antimicrobial resistance have created a momentum to implement clinical bacteriology in low-resource settings. Successful implementation relies on guidance by a quality management system (QMS). Over the past decade international initiatives were launched towards implementation of QMS in HIV/AIDS, tuberculosis and malaria. To describe the progress towards accreditation of medical laboratories and to identify the challenges and best practices for implementation of QMS in clinical bacteriology in low-resource settings. Published literature, online reports and websites related to the implementation of laboratory QMS, accreditation of medical laboratories and initiatives for containment of antimicrobial resistance. Apart from the limitations of infrastructure, equipment, consumables and staff, QMS are challenged with the complexity of clinical bacteriology and the healthcare context in low-resource settings (small-scale laboratories, attitudes and perception of staff, absence of laboratory information systems). Likewise, most international initiatives addressing laboratory health strengthening have focused on public health and outbreak management rather than on hospital based patient care. Best practices to implement quality-assured clinical bacteriology in low-resource settings include alignment with national regulations and public health reference laboratories, participating in external quality assurance programmes, support from the hospital's management, starting with attainable projects, conducting error review and daily bench-side supervision, looking for locally adapted solutions, stimulating ownership and extending existing training programmes to clinical bacteriology. The implementation of QMS in clinical bacteriology in hospital settings will ultimately boost a culture of quality to all sectors of healthcare in low-resource settings. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Middle Managers' Experiences and Role in Implementing an Interactive Tailored Patient Assessment eHealth Intervention in Clinical Practice.

PubMed

Varsi, Cecilie; Ekstedt, Mirjam; Gammon, Deede; Børøsund, Elin; Ruland, Cornelia M

2015-06-01

The role of nurse and physician managers is considered crucial for implementing eHealth interventions in clinical practice, but few studies have explored this. The aim of the current study was to examine the perceptions of nurse and physician managers regarding facilitators, barriers, management role, responsibility, and action taken in the implementation of an eHealth intervention called Choice into clinical practice. Individual qualitative interviews were conducted with six nurses and three physicians in management positions at five hospital units. The findings revealed that nurse managers reported conscientiously supporting the implementation, but workloads prevented them from participating in the process as closely as they wanted. Physician managers reported less contribution. The implementation process was influenced by facilitating factors such as perceptions of benefits from Choice and use of implementation strategies, along with barriers such as physician resistance, contextual factors and difficulties for front-line providers in learning a new way of communicating with the patients. The findings suggest that role descriptions for both nurse and physician managers should include implementation knowledge and implementation skills. Managers could benefit from an implementation toolkit. Implementation management should be included in management education for healthcare managers to prepare them for the constant need for implementation and improvement in clinical practice.

Care provider order entry (CPOE): a perspective on factors leading to success or to failure.

PubMed

Ozdas, A; Miller, R A

2007-01-01

Authors provide a perspective on factors leading to successful care provider order entry (CPOE) implementations. Viewpoint of authors supported by background literature review. Authors review both benefits and challenges related to CPOE implementation using three guiding principles: (1) a clinical approach to clinical systems, which claims that CPOE implementation is analogous to a "good" clinician delivering care to a patient; (2) a commitment to quality, which advocates that no compromises should be made in implementing system functionality and clinical system content - the highest objective for CPOE implementation is to provide better quality of care and increased safety for patients; (3) a commitment to fairness, as evidenced by respect for individuals and support of local autonomy, which advocates for minimizing disruptions to clinician-users' workflows, and adequate local control over CPOE system design and evolution, including clinical content management. Past experiences with CPOE implementation can inform future installation attempts. Sociocultural factors dominate in determining the success of implementation, and should govern technical factors.

Factors affecting the implementation of clinical pharmacy services in China.

PubMed

Penm, Jonathan; Moles, Rebekah; Wang, Holly; Li, Yan; Chaar, Betty

2014-03-01

New policies in China have recently led to the implementation of clinical pharmacy services in hospitals. We explored the views of hospital administrators, pharmacy directors, clinical pharmacists, and dispensing pharmacists about the factors affecting clinical pharmacy services in China, using the framework approach and organizational theory. We conducted 30 interviews with 130 participants at 29 hospitals (both secondary and tertiary) in Beijing, Zhengzhou, Luoyang, and Shanghai. We found that the barriers to and facilitators of implementation of clinical pharmacy services slotted into the environment and participant dimensions of Scott's adapted version of Leavitt's organizational model. External support from government was perceived as crucial to promoting pharmacy services. It is proposed that the internationally recognized Basel Statements of the International Pharmaceutical Federation also provide a strong foundation for guiding China in implementing clinical pharmacy services.

In-situ medical simulation for pre-implementation testing of clinical service in a regional hospital in Hong Kong.

PubMed

Chen, P P; Tsui, N Tk; Fung, A Sw; Chiu, A Hf; Wong, W Cw; Leong, H T; Lee, P Sf; Lau, J Yw

2017-08-01

The implementation of a new clinical service is associated with anxiety and challenges that may prevent smooth and safe execution of the service. Unexpected issues may not be apparent until the actual clinical service commences. We present a novel approach to test the new clinical setting before actual implementation of our endovascular aortic repair service. In-situ simulation at the new clinical location would enable identification of potential process and system issues prior to implementation of the service. After preliminary planning, a simulation test utilising a case scenario with actual simulation of the entire care process was carried out to identify any logistic, equipment, settings or clinical workflow issues, and to trial a contingency plan for a surgical complication. All patient care including anaesthetic, surgical, and nursing procedures and processes were simulated and tested. Overall, 17 vital process and system issues were identified during the simulation as potential clinical concerns. They included difficult patient positioning, draping pattern, unsatisfactory equipment setup, inadequate critical surgical instruments, blood products logistics, and inadequate nursing support during crisis. In-situ simulation provides an innovative method to identify critical deficiencies and unexpected issues before implementation of a new clinical service. Life-threatening and serious practical issues can be identified and corrected before formal service commences. This article describes our experience with the use of simulation in pre-implementation testing of a clinical process or service. We found the method useful and would recommend it to others.

Implementation of an Electronic Health Records System in a Small Clinic: The Viewpoint of Clinic Staff

ERIC Educational Resources Information Center

Carayon, Pascale; Smith, Paul; Hundt, Ann Schoofs; Kuruchittham, Vipat; Li, Qian

2009-01-01

In this study, we examined the implementation of an electronic health records (EHR) system in a small family practice clinic. We used three data collection instruments to evaluate user experience, work pattern changes, and organisational changes related to the implementation and use of the EHR system: (1) an EHR user survey, (2) interviews with…

The facilitators and barriers associated with implementation of a patient-centered medical home in VHA.

PubMed

Helfrich, Christian D; Sylling, Philip W; Gale, Randall C; Mohr, David C; Stockdale, Susan E; Joos, Sandra; Brown, Elizabeth J; Grembowski, David; Asch, Steven M; Fihn, Stephan D; Nelson, Karin M; Meredith, Lisa S

2016-02-24

The patient-centered medical home (PCMH) is a team-based, comprehensive model of primary care. When effectively implemented, PCMH is associated with higher patient satisfaction, lower staff burnout, and lower hospitalization for ambulatory care-sensitive conditions. However, less is known about what factors contribute to (or hinder) PCMH implementation. We explored the associations of specific facilitators and barriers reported by primary care employees with a previously validated, clinic-level measure of PCMH implementation, the Patient Aligned Care Team Implementation Progress Index (Pi(2)). We used a 2012 survey of primary care employees in the Veterans Health Administration to perform cross-sectional, respondent-level multinomial regressions. The dependent variable was the Pi(2) categorized as high implementation (top decile, 54 clinics, 235 respondents), medium implementation (middle eight deciles, 547 clinics, 4537 respondents), and low implementation (lowest decile, 42 clinics, 297 respondents) among primary care clinics. The independent variables were ordinal survey items rating 19 barriers to patient-centered care and 10 facilitators of PCMH implementation. For facilitators, we explored clinic Pi(2) score decile both as a function of respondent-reported availability of facilitators and of rating of facilitator helpfulness. The availability of five facilitators was associated with higher odds of a respondent's clinic's Pi(2) scores being in the highest versus lowest decile: teamlet huddles (OR = 3.91), measurement tools (OR = 3.47), regular team meetings (OR = 2.88), information systems (OR = 2.42), and disease registries (OR = 2.01). The helpfulness of four facilitators was associated with higher odds of a respondent's clinic's Pi(2) scores being in the highest versus lowest decile. Six barriers were associated with significantly higher odds of a respondent's clinic's Pi(2) scores being in the lowest versus highest decile, with the strongest associations for the difficulty recruiting and retaining providers (OR = 2.37) and non-provider clinicians (OR = 2.17). Results for medium versus low Pi(2) score clinics were similar, with fewer, smaller significant associations, all in the expected direction. A number of specific barriers and facilitators were associated with PCMH implementation, notably recruitment and retention of clinicians, team huddles, and local education. These findings can guide future research, and may help healthcare policy makers and leaders decide where to focus attention and limited resources.

Policies and Procedures That Facilitate Implementation of Evidence-Based Clinical Guidelines in U.S. Dental Schools.

PubMed

Polk, Deborah E; Nolan, Beth A D; Shah, Nilesh H; Weyant, Robert J

2016-01-01

The aim of this study was to determine the degree to which dental schools in the United States have policies and procedures in place that facilitate the implementation of evidence-based clinical guidelines. The authors sent surveys to all 65 U.S. dental schools in 2014; responses were obtained from 38 (58%). The results showed that, of the nine policies and procedures examined, only two were fully implemented by 50% or more of the responding schools: guidelines supported through clinical faculty education or available chairside (50%), and students informed of guidelines in both the classroom and clinic (65.8%). Although 92% of the respondents reported having an electronic health record, 80% of those were not using it to track compliance with guidelines. Five schools reported implementing more policies than the rest of the schools. The study found that the approach to implementing guidelines at most of the responding schools did not follow best practices although five schools had an exemplary set of policies and procedures to support guideline implementation. These results suggest that most dental schools are currently not implementing guidelines effectively and efficiently, but that the goal of schools' having a comprehensive implementation program for clinical guidelines is achievable since some are doing so. Future studies should determine whether interventions to improve implementation in dental schools are needed.

Novel Application of a Reverse Triage Protocol Providing Increased Access to Care in an Outpatient, Primary Care Clinic Setting.

PubMed

Sacino, Amanda N; Shuster, Jonathan J; Nowicki, Kamil; Carek, Peter J; Wegman, Martin P; Listhaus, Alyson; Gibney, Joseph M; Chang, Ku-Lang

2016-02-01

As the number of patients with access to care increases, outpatient clinics will need to implement innovative strategies to maintain or enhance clinic efficiency. One viable alternative involves reverse triage. A reverse triage protocol was implemented during a student-run free clinic. Each patient's chief complaint(s) were obtained at the beginning of the clinic session and ranked by increasing complexity. "Complexity" was defined as the subjective amount of time required to provide a full, thorough evaluation of a patient. Less complex cases were prioritized first since they could be expedited through clinic processing and allow for more time and resources to be dedicated to complex cases. Descriptive statistics were used to characterize and summarize the data obtained. Categorical variables were analyzed using chi-square. A time series analysis of the outcome versus centered time in weeks was also conducted. The average number of patients seen per clinic session increased by 35% (9.5 versus 12.8) from pre-implementation of the reverse triage protocol to 6 months after the implementation of the protocol. The implementation of a reverse triage in an outpatient setting significantly increased clinic efficiency as noted by a significant increase in the number of patients seen during a clinic session.

Preemptive clinical pharmacogenetics implementation: current programs in five US medical centers.

PubMed

Dunnenberger, Henry M; Crews, Kristine R; Hoffman, James M; Caudle, Kelly E; Broeckel, Ulrich; Howard, Scott C; Hunkler, Robert J; Klein, Teri E; Evans, William E; Relling, Mary V

2015-01-01

Although the field of pharmacogenetics has existed for decades, practioners have been slow to implement pharmacogenetic testing in clinical care. Numerous publications describe the barriers to clinical implementation of pharmacogenetics. Recently, several freely available resources have been developed to help address these barriers. In this review, we discuss current programs that use preemptive genotyping to optimize the pharmacotherapy of patients. Array-based preemptive testing includes a large number of relevant pharmacogenes that impact multiple high-risk drugs. Using a preemptive approach allows genotyping results to be available prior to any prescribing decision so that genomic variation may be considered as an inherent patient characteristic in the planning of therapy. This review describes the common elements among programs that have implemented preemptive genotyping and highlights key processes for implementation, including clinical decision support.

SU-E-T-589: Optimization of Patient Head Angle Position to Spare Hippocampus During the Brain Radiation Therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheon, G; Kang, Y; Kang, S

Purpose: Hippocampus is one of the important organs which controls emotions, behaviors, movements the memorizing and learning ability. In the conventional head & neck therapy position, it is difficult to perform the hippocampal-sparing brain radiation therapy. The purpose of this study is to investigate optimal head angle which can save the hippocampal-sparing and organ at risk (OAR) in conformal radiation therapy (CRT), Intensity modulation radiation therapy (IMRT) and helical tomotherapy (HT). Methods: Three types of radiation treatment plans, CRT, IMRT and Tomotherapy plans, were performed for 10 brain tumor patients. The image fusion between CT and MRI data were usedmore » in the contour due to the limited delineation of the target and OAR in the CT scan. The optimal condition plan was determined by comparing the dosimetric performance of the each plan with the use of various parameters which include three different techniques (CRT, IMRT, HT) and 4 angle (0, 15, 30, 40 degree). The each treatment plans of three different techniques were compared with the following parameters: conformity index (CI), homogeneity index (HI), target coverage, dose in the OARs, monitor units (MU), beam on time and the normal tissue complication probability (NTCP). Results: HI, CI and target coverage was most excellent in head angle 30 degree among all angle. When compared by modality, target coverage and CI showed good results in IMRT and TOMO than compared to the CRT. HI at the head angle 0 degrees is 1.137±0.17 (CRT), 1.085±0.09 (IMRT) and 1.077±0.06 (HT). HI at the head angle 30 degrees is 1.056±0.08 (CRT), 1.020±0.05 (IMRT) and 1.022±0.07 (HT). Conclusion: The results of our study show that when head angle tilted at 30 degree, target coverage, HI, CI were improved, and the dose delivered to OAR was reduced compared with conventional supine position in brain radiation therapy. This work was supported by the Radiation Technology R&D program (No. 2013M2A2A7043498) and the Mid-career Researcher Program (2014R1A2A1A10050270) through the National Research Foundation of Korea funded by the Ministry of Science, ICT&Future Planning.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Levegruen, Sabine, E-mail: sabine.levegruen@uni-due.de; Poettgen, Christoph; Abu Jawad, Jehad

Purpose: To evaluate megavoltage computed tomography (MVCT)-based image guidance with helical tomotherapy in patients with vertebral tumors by analyzing factors influencing interobserver variability, considered as quality criterion of image guidance. Methods and Materials: Five radiation oncologists retrospectively registered 103 MVCTs in 10 patients to planning kilovoltage CTs by rigid transformations in 4 df. Interobserver variabilities were quantified using the standard deviations (SDs) of the distributions of the correction vector components about the observers' fraction mean. To assess intraobserver variabilities, registrations were repeated after {>=}4 weeks. Residual deviations after setup correction due to uncorrectable rotational errors and elastic deformations were determinedmore » at 3 craniocaudal target positions. To differentiate observer-related variations in minimizing these residual deviations across the 3-dimensional MVCT from image resolution effects, 2-dimensional registrations were performed in 30 single transverse and sagittal MVCT slices. Axial and longitudinal MVCT image resolutions were quantified. For comparison, image resolution of kilovoltage cone-beam CTs (CBCTs) and interobserver variability in registrations of 43 CBCTs were determined. Results: Axial MVCT image resolution is 3.9 lp/cm. Longitudinal MVCT resolution amounts to 6.3 mm, assessed as full-width at half-maximum of thin objects in MVCTs with finest pitch. Longitudinal CBCT resolution is better (full-width at half-maximum, 2.5 mm for CBCTs with 1-mm slices). In MVCT registrations, interobserver variability in the craniocaudal direction (SD 1.23 mm) is significantly larger than in the lateral and ventrodorsal directions (SD 0.84 and 0.91 mm, respectively) and significantly larger compared with CBCT alignments (SD 1.04 mm). Intraobserver variabilities are significantly smaller than corresponding interobserver variabilities (variance ratio [VR] 1.8-3.1). Compared with 3-dimensional registrations, 2-dimensional registrations have significantly smaller interobserver variability in the lateral and ventrodorsal directions (VR 3.8 and 2.8, respectively) but not in the craniocaudal direction (VR 0.75). Conclusion: Tomotherapy image guidance precision is affected by image resolution and residual deviations after setup correction. Eliminating the effect of residual deviations yields small interobserver variabilities with submillimeter precision in the axial plane. In contrast, interobserver variability in the craniocaudal direction is dominated by the poorer longitudinal MVCT image resolution. Residual deviations after image guidance exist and need to be considered when dose gradients ultimately achievable with image guided radiation therapy techniques are analyzed.« less

Surface imaging, laser positioning or volumetric imaging for breast cancer with nodal involvement treated by helical TomoTherapy.

PubMed

Crop, Frederik; Pasquier, David; Baczkiewic, Amandine; Doré, Julie; Bequet, Lena; Steux, Emeline; Gadroy, Anne; Bouillon, Jacqueline; Florence, Clement; Muszynski, Laurence; Lacour, Mathilde; Lartigau, Eric

2016-09-08

A surface imaging system, Catalyst (C-Rad), was compared with laser-based positioning and daily mega voltage computed tomography (MVCT) setup for breast patients with nodal involvement treated by helical TomoTherapy. Catalyst-based positioning performed better than laser-based positioning. The respective modalities resulted in a standard deviation (SD), 68% confidence interval (CI) of positioning of left-right, craniocaudal, anterior-posterior, roll: 2.4 mm, 2.7 mm, 2.4 mm, 0.9° for Catalyst positioning, and 6.1 mm, 3.8 mm, 4.9 mm, 1.1° for laser-based positioning, respectively. MVCT-based precision is a combination of the interoperator variability for MVCT fusion and the patient movement during the time it takes for MVCT and fusion. The MVCT fusion interoperator variability for breast patients was evaluated at one SD left-right, craniocaudal, ant-post, roll as: 1.4 mm, 1.8 mm, 1.3 mm, 1.0°. There was no statistically significant difference between the automatic MVCT registration result and the manual adjustment; the automatic fusion results were within the 95% CI of the mean result of 10 users, except for one specific case where the patient was positioned with large yaw. We found that users add variability to the roll correction as the automatic registration was more consistent. The patient position uncertainty confidence interval was evaluated as 1.9 mm, 2.2 mm, 1.6 mm, 0.9° after 4 min, and 2.3 mm, 2.8 mm, 2.2 mm, 1° after 10 min. The combination of this patient movement with MVCT fusion interoperator variability results in total standard deviations of patient posi-tion when treatment starts 4 or 10 min after initial positioning of, respectively: 2.3 mm, 2.8 mm, 2.0 mm, 1.3° and 2.7 mm, 3.3 mm, 2.6 mm, 1.4°. Surface based positioning arrives at the same precision when taking into account the time required for MVCT imaging and fusion. These results can be used on a patient-per-patient basis to decide which positioning system performs the best after the first 5 fractions and when daily MVCT can be omitted. Ideally, real-time monitoring is required to reduce important intrafraction movement. © 2016 The Authors.

Dosimetric comparison of helical tomotherapy, RapidArc, and a novel IMRT & Arc technique for esophageal carcinoma.

PubMed

Martin, Spencer; Chen, Jeff Z; Rashid Dar, A; Yartsev, Slav

2011-12-01

To compare radiotherapy treatment plans for mid- and distal-esophageal cancer with primary involvement of the gastroesophageal (GE) junction using a novel IMRT & Arc technique (IMRT & Arc), helical tomotherapy (HT), and RapidArc (RA1 and RA2). Eight patients treated on HT for locally advanced esophageal cancer with radical intent were re-planned for RA and IMRT&Arc. RA plans employed single and double arcs (RA1 and RA2, respectively), while IMRT&Arc plans had four fixed-gantry IMRT fields and a conformal arc. Dose-volume histogram statistics, dose uniformity, and dose homogeneity were analyzed to compare treatment plans. RA2 plans showed significant improvement over RA1 plans in terms of OAR dose and PTV dose uniformity and homogeneity. HT plan provided best dose uniformity (p=0.001) and dose homogeneity (p=0.002) to planning target volume (PTV), while IMRT&Arc and RA2 plans gave lowest dose to lungs among four radiotherapy techniques with acceptable PTV dose coverage. Mean V(10) of the lungs was significantly reduced by the RA2 plans compared to IMRT&Arc (40.3%, p=0.001) and HT (66.2%, p<0.001) techniques. Mean V(15) of the lungs for the RA2 plans also showed significant improvement over the IMRT&Arc (25.2%, p=0.042) and HT (34.8%, p=0.027) techniques. These improvements came at the cost of higher doses to the heart volume compared to HT and IMRT&Arc techniques. Mean lung dose (MLD) for the IMRT&Arc technique (21.2 ± 5.0% of prescription dose) was significantly reduced compared to HT (26.3%, p=0.004), RA1 (23.3%, p=0.028), and RA2 (23.2%, p=0.017) techniques. The IMRT&Arc technique is a good option for treating esophageal cancer with thoracic involvement. It achieved optimal low dose to the lungs and heart with acceptable PTV coverage. HT is a good option for treating esophageal cancer with little thoracic involvement as it achieves superior dose conformality and uniformity. The RA2 technique provided for improved treatment plans using additional arcs with low doses to the lungs at the cost of increased heart dose. Plan quality could still be improved through the use of additional arcs. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

A Dosimetric Comparison of Breast Radiotherapy Techniques to Treat Locoregional Lymph Nodes Including the Internal Mammary Chain.

PubMed

Ranger, A; Dunlop, A; Hutchinson, K; Convery, H; Maclennan, M K; Chantler, H; Twyman, N; Rose, C; McQuaid, D; Amos, R A; Griffin, C; deSouza, N M; Donovan, E; Harris, E; Coles, C E; Kirby, A

2018-06-01

Radiotherapy target volumes in early breast cancer treatment increasingly include the internal mammary chain (IMC). In order to maximise survival benefits of IMC radiotherapy, doses to the heart and lung should be minimised. This dosimetry study compared the ability of three-dimensional conformal radiotherapy, arc therapy and proton beam therapy (PBT) techniques with and without breath-hold to achieve target volume constraints while minimising dose to organs at risk (OARs). In 14 patients' datasets, seven IMC radiotherapy techniques were compared: wide tangent (WT) three-dimensional conformal radiotherapy, volumetric-modulated arc therapy (VMAT) and PBT, each in voluntary deep inspiratory breath-hold (vDIBH) and free breathing (FB), and tomotherapy in FB only. Target volume coverage and OAR doses were measured for each technique. These were compared using a one-way ANOVA with all pairwise comparisons tested using Bonferroni's multiple comparisons test, with adjusted P-values ≤ 0.05 indicating statistical significance. One hundred per cent of WT(vDIBH), 43% of WT(FB), 100% of VMAT(vDIBH), 86% of VMAT(FB), 100% of tomotherapy FB and 100% of PBT plans in vDIBH and FB passed all mandatory constraints. However, coverage of the IMC with 90% of the prescribed dose was significantly better than all other techniques using VMAT(vDIBH), PBT(vDIBH) and PBT(FB) (mean IMC coverage ± 1 standard deviation = 96.0% ± 4.3, 99.8% ± 0.3 and 99.0% ± 0.2, respectively). The mean heart dose was significantly reduced in vDIBH compared with FB for both the WT (P < 0.0001) and VMAT (P < 0.0001) techniques. There was no advantage in target volume coverage or OAR doses for PBT(vDIBH) compared with PBT(FB). Simple WT radiotherapy delivered in vDIBH achieves satisfactory coverage of the IMC while meeting heart and lung dose constraints. However, where higher isodose coverage is required, VMAT(vDIBH) is the optimal photon technique. The lowest OAR doses are achieved by PBT, in which the use of vDIBH does not improve dose statistics. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.

Assessing the effectiveness of strategies to implement clinical guidelines for the management of chronic diseases at primary care level in EU Member States: a systematic review.

PubMed

Brusamento, Serena; Legido-Quigley, Helena; Panteli, Dimitra; Turk, Eva; Knai, Cecile; Saliba, Vanessa; Car, Josip; McKee, Martin; Busse, Reinhard

2012-10-01

This review aimed to evaluate the effectiveness of strategies to implement clinical guidelines for chronic disease management in primary care in EU Member States. We conducted a systematic review of interventional studies assessing the implementation of clinical guidelines. We searched five databases (EMBASE, MEDLINE, CENTRAL, Eppi-Centre and Clinicaltrials.gov) following a strict Cochrane methodology. We included studies focusing on the management of chronic diseases in adults in primary care. A total of 21 studies were found. The implementation strategy was fully effective in only four (19%), partially effective in eight (38%), and not effective in nine (43%). The probability that an intervention would be effective was only slightly higher with multifaceted strategies, compared to single interventions. However, effect size varied across studies; therefore it was not possible to determine the most successful strategy. Only eight studies evaluated the impact on patients' health and only two of those showed significant improvement, while in five there was an improvement in the process of care which did not translate into an improvement in health outcomes. Only four studies reported any data on the cost of the implementation but none undertook a cost-effectiveness analysis. Only one study presented data on the barriers to the implementation of guidelines, noting a lack of awareness and agreement about clinical guidelines. Our results reveal that there are only a few rigorous studies which assess the effectiveness of a strategy to implement clinical guidelines in Europe. Moreover, the results are not consistent in showing which strategy is the most appropriate to facilitate their implementation. Therefore, further research is needed to develop more rigorous studies to evaluate health outcomes associated with the implementation of clinical guidelines; to assess the cost-effectiveness of implementing clinical guidelines; and to investigate the perspective of service users and health service staff. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Testing the 4Rs and 2Ss Multiple Family Group intervention: study protocol for a randomized controlled trial.

PubMed

Acri, Mary; Hamovitch, Emily; Mini, Maria; Garay, Elene; Connolly, Claire; McKay, Mary

2017-12-04

Oppositional defiant disorder (ODD) is a major mental health concern and highly prevalent among children living in poverty-impacted communities. Despite that treatments for ODD are among the most effective, few children living in poverty receive these services due to substantial barriers to access, as well as difficulties in the uptake and sustained adoption of evidence-based practices (EBPs) in community settings. The purpose of this study is to examine implementation processes that impact uptake of an evidence-based practice for childhood ODD, and the impact of a Clinic Implementation Team (CIT)-driven structured adaptation to enhance its fit within the public mental health clinic setting. This study, a Hybrid Type II effectiveness-implementation research trial, blends clinical effectiveness and implementation research methods to examine the impact of the 4Rs and 2Ss Multiple Family Group (MFG) intervention, family level mediators of child outcomes, clinic/provider-level mediators of implementation, and the impact of CITs on uptake and long-term utilization of this model. All New York City public outpatient mental health clinics have been invited to participate. A sampling procedure that included randomization at the agency level and a sub-study to examine the impact of clinic choice upon outcomes yielded a distribution of clinics across three study conditions. Quantitative data measuring child outcomes, organizational factors and implementation fidelity will be collected from caregivers and providers at baseline, 8, and 16 weeks from baseline, and 6 months from treatment completion. The expected participation is 134 clinics, 268 providers, and 2688 caregiver/child dyads. We will use mediation analysis with a multi-level Structural Equation Modeling (SEM) (MSEM including family level variables, provider variables, and clinic variables), as well as mediation tests to examine study hypotheses. The aim of the study is to generate knowledge about effectiveness and mediating factors in the treatment of ODDs in children in the context of family functioning, and to propose an innovative approach to the adaptation and implementation of new treatment interventions within clinic settings. The proposed CIT adaptation and implementation model has the potential to enhance implementation and sustainability, and ultimately increase the extent to which effective interventions are available and can impact children and families in need of services for serious behavior problems. ClinicalTrials.gov, ID: NCT02715414 . Registered on 3 March 2016.

Organizational correlates of implementation of colocation of mental health and primary care in the Veterans Health Administration.

PubMed

Guerrero, Erick G; Heslin, Kevin C; Chang, Evelyn; Fenwick, Karissa; Yano, Elizabeth

2015-07-01

This study explored the role of organizational factors in the ability of Veterans Health Administration (VHA) clinics to implement colocated mental health care in primary care settings (PC-MH). The study used data from the VHA Clinical Practice Organizational Survey collected in 2007 from 225 clinic administrators across the United States. Clinic degree of implementation of PC-MH was the dependent variable, whereas independent variables included policies and procedures, organizational context, and leaders' perceptions of barriers to change. Pearson bivariate correlations and multivariable linear regression were used to test hypotheses. Results show that depression care training for primary care providers and clinics' flexibility and participation were both positively correlated with implementation of PC-MH. However, after accounting for other factors, regressions show that only training primary care providers in depression care was marginally associated with degree of implementation of PC-MH (p = 0.051). Given the importance of this topic for implementing integrated care as part of health care reform, these null findings underscore the need to improve theory and testing of more proximal measures of colocation in future work.

Providing Specialty Care for the Poor and Underserved at Student-Run Free Clinics in the San Francisco Bay Area.

PubMed

Liu, Max Bolun; Xiong, Grace; Boggiano, Victoria Lynn; Ye, Patrick Peiyong; Lin, Steven

2017-01-01

This report describes the model of specialty clinics implemented at Stanford University's two student-run free clinics, Arbor Free Clinic and Pacific Free Clinic, in the San Francisco Bay Area. We describe our patient demographic characteristics and the specialty services provided. We discuss challenges in implementing specialty care at student-run free clinics.

Implementing a Measurement Feedback System: A Tale of Two Sites

PubMed Central

Douglas, Susan R.; Vides De Andrade, Ana Regina; Tomlinson, Michele; Gleacher, Alissa; Olin, Serene; Hoagwood, Kimberly

2015-01-01

A randomized experiment was conducted in two outpatient clinics evaluating a measurement feedback system called contextualized feedback systems. The clinicians of 257 Youth 11–18 received feedback on progress in mental health symptoms and functioning either every 6 months or as soon as the youth’s, clinician’s or caregiver’s data were entered into the system. The ITT analysis showed that only one of the two participating clinics (Clinic R) had an enhanced outcome because of feedback, and only for the clinicians’ ratings of youth symptom severity on the SFSS. A dose–response effect was found only for Clinic R for both the client and clinician ratings. Implementation analyses showed that Clinic R had better implementation of the feedback intervention. Clinicians’ questionnaire completion rate and feedback viewing at Clinic R were 50 % higher than clinicians at Clinic U. The discussion focused on the differences in implementation at each site and how these differences may have contributed to the different outcomes of the experiment. PMID:25876736

Preemptive Clinical Pharmacogenetics Implementation: Current programs in five United States medical centers

PubMed Central

Dunnenberger, Henry M.; Crews, Kristine R.; Hoffman, James M.; Caudle, Kelly E.; Broeckel, Ulrich; Howard, Scott C.; Hunkler, Robert J.; Klein, Teri E.; Evans, William E.; Relling, Mary V.

2015-01-01

Although the field of pharmacogenetics has existed for decades, the implementation of, pharmacogenetic testing in clinical care has been slow. There are numerous publications, describing the barriers to clinical implementation of pharmacogenetics. Recently, several freely, available resources have been developed to help address these barriers. In this review we, discuss current programs that use preemptive genotyping to optimize the pharmacotherapy of, patients. Array-based preemptive testing includes a large number of relevant pharmacogenes, that impact multiple high-risk drugs. Using a preemptive approach allows genotyping results to, be available prior to any prescribing decision so that genomic variation may be considered as, an inherent patient characteristic in the planning of therapy. This review describes the common, elements among programs that have implemented preemptive genotyping and highlights key, processes for implementation, including clinical decision support. PMID:25292429

Effectiveness of implementation strategies for clinical guidelines to community pharmacy: a systematic review.

PubMed

Watkins, Kim; Wood, Helen; Schneider, Carl R; Clifford, Rhonda

2015-10-29

The clinical role of community pharmacists is expanding, as is the use of clinical guidelines in this setting. However, it is unclear which strategies are successful in implementing clinical guidelines and what outcomes can be achieved. The aim of this systematic review is to synthesise the literature on the implementation of clinical guidelines to community pharmacy. The objectives are to describe the implementation strategies used, describe the resulting outcomes and to assess the effectiveness of the strategies. A systematic search was performed in six electronic databases (Medline, EMBASE, CINAHL, Web of Science, Informit, Cochrane Library) for relevant articles. Studies were included if they reported on clinical guidelines implementation strategies in the community pharmacy setting. Two researchers completed the full-search strategy, data abstraction and quality assessments, independently. A third researcher acted as a moderator. Quality assessments were completed with three validated tools. A narrative synthesis was performed to analyse results. A total of 1937 articles were retrieved and the titles and abstracts were screened. Full-text screening was completed for 36 articles resulting in 19 articles (reporting on 22 studies) included for review. Implementation strategies were categorised according to a modified version of the EPOC taxonomy. Educational interventions were the most commonly utilised strategy (n = 20), and computerised decision support systems demonstrated the greatest effect (n = 4). Most studies were multifaceted and used more than one implementation strategy (n = 18). Overall outcomes were moderately positive (n = 17) but focused on process (n = 22) rather than patient (n = 3) or economic outcomes (n = 3). Most studies (n = 20) were rated as being of low methodological quality and having low or very low quality of evidence for outcomes. Studies in this review did not generally have a well thought-out rationale for the choice of implementation strategy. Most utilised educational strategies, but the greatest effect on outcomes was demonstrated using computerised clinical decision support systems. Poor methodology, in the majority of the research, provided insufficient evidence to be conclusive about the best implementation strategies or the benefit of clinical guidelines in this setting. However, the generally positive outcomes across studies and strategies indicate that implementing clinical guidelines to community pharmacy might be beneficial. Improved methodological rigour in future research is required to strengthen the evidence for this hypothesis. PROSPERO 2012: CRD42012003019 .

Implementation of internet-delivered cognitive behavior therapy within community mental health clinics: a process evaluation using the consolidated framework for implementation research.

PubMed

Hadjistavropoulos, H D; Nugent, M M; Dirkse, D; Pugh, N

2017-09-12

Depression and anxiety are prevalent and under treated conditions that create enormous burden for the patient and the health system. Internet-delivered cognitive behavior therapy (ICBT) improves patient access to treatment by providing therapeutic information via the Internet, presented in sequential lessons, accompanied by brief weekly therapist support. While there is growing research supporting ICBT, use of ICBT within community mental health clinics is limited. In a recent trial, an external unit specializing in ICBT facilitated use of ICBT in community mental health clinics in one Canadian province (ISRCTN42729166; registered November 5, 2013). Patient outcomes were very promising and uptake was encouraging. This paper reports on a parallel process evaluation designed to understand facilitators and barriers impacting the uptake and implementation of ICBT. Therapists (n = 22) and managers (n = 11) from seven community mental health clinics dispersed across one Canadian province who were involved in implementing ICBT over ~2 years completed an online survey (including open and closed-ended questions) about ICBT experiences. The questions were based on the Consolidated Framework for Implementation Research (CFIR), which outlines diverse constructs that have the potential to impact program implementation. Analyses suggested ICBT implementation was perceived to be most prominently facilitated by intervention characteristics (namely the relative advantages of ICBT compared to face-to-face therapy, the quality of the ICBT program that was delivered, and evidence supporting ICBT) and implementation processes (namely the use of an external facilitation unit that aided with engaging patients, therapists, and managers and ICBT implementation). The inner setting was identified as the most significant barrier to implementation as a result of limited resources for ICBT combined with greater priority given to face-to-face care. The results contribute to understanding facilitators and barriers to using ICBT within community mental health clinics and serve to identify recommendations for improving uptake and implementation of ICBT in clinic settings.

Evaluation of Electronic Health Record Implementation in Ophthalmology at an Academic Medical Center (An American Ophthalmological Society Thesis)

PubMed Central

Chiang, Michael F.; Read-Brown, Sarah; Tu, Daniel C.; Choi, Dongseok; Sanders, David S.; Hwang, Thomas S.; Bailey, Steven; Karr, Daniel J.; Cottle, Elizabeth; Morrison, John C.; Wilson, David J.; Yackel, Thomas R.

2013-01-01

Purpose: To evaluate three measures related to electronic health record (EHR) implementation: clinical volume, time requirements, and nature of clinical documentation. Comparison is made to baseline paper documentation. Methods: An academic ophthalmology department implemented an EHR in 2006. A study population was defined of faculty providers who worked the 5 months before and after implementation. Clinical volumes, as well as time length for each patient encounter, were collected from the EHR reporting system. To directly compare time requirements, two faculty providers who utilized both paper and EHR systems completed time-motion logs to record the number of patients, clinic time, and nonclinic time to complete documentation. Faculty providers and databases were queried to identify patient records containing both paper and EHR notes, from which three cases were identified to illustrate representative documentation differences. Results: Twenty-three faculty providers completed 120,490 clinical encounters during a 3-year study period. Compared to baseline clinical volume from 3 months pre-implementation, the post-implementation volume was 88% in quarter 1, 93% in year 1, 97% in year 2, and 97% in year 3. Among all encounters, 75% were completed within 1.7 days after beginning documentation. The mean total time per patient was 6.8 minutes longer with EHR than paper (P<.01). EHR documentation involved greater reliance on textual interpretation of clinical findings, whereas paper notes used more graphical representations, and EHR notes were longer and included automatically generated text. Conclusion: This EHR implementation was associated with increased documentation time, little or no increase in clinical volume, and changes in the nature of ophthalmic documentation. PMID:24167326

Implementation of workflow engine technology to deliver basic clinical decision support functionality.

PubMed

Huser, Vojtech; Rasmussen, Luke V; Oberg, Ryan; Starren, Justin B

2011-04-10

Workflow engine technology represents a new class of software with the ability to graphically model step-based knowledge. We present application of this novel technology to the domain of clinical decision support. Successful implementation of decision support within an electronic health record (EHR) remains an unsolved research challenge. Previous research efforts were mostly based on healthcare-specific representation standards and execution engines and did not reach wide adoption. We focus on two challenges in decision support systems: the ability to test decision logic on retrospective data prior prospective deployment and the challenge of user-friendly representation of clinical logic. We present our implementation of a workflow engine technology that addresses the two above-described challenges in delivering clinical decision support. Our system is based on a cross-industry standard of XML (extensible markup language) process definition language (XPDL). The core components of the system are a workflow editor for modeling clinical scenarios and a workflow engine for execution of those scenarios. We demonstrate, with an open-source and publicly available workflow suite, that clinical decision support logic can be executed on retrospective data. The same flowchart-based representation can also function in a prospective mode where the system can be integrated with an EHR system and respond to real-time clinical events. We limit the scope of our implementation to decision support content generation (which can be EHR system vendor independent). We do not focus on supporting complex decision support content delivery mechanisms due to lack of standardization of EHR systems in this area. We present results of our evaluation of the flowchart-based graphical notation as well as architectural evaluation of our implementation using an established evaluation framework for clinical decision support architecture. We describe an implementation of a free workflow technology software suite (available at http://code.google.com/p/healthflow) and its application in the domain of clinical decision support. Our implementation seamlessly supports clinical logic testing on retrospective data and offers a user-friendly knowledge representation paradigm. With the presented software implementation, we demonstrate that workflow engine technology can provide a decision support platform which evaluates well against an established clinical decision support architecture evaluation framework. Due to cross-industry usage of workflow engine technology, we can expect significant future functionality enhancements that will further improve the technology's capacity to serve as a clinical decision support platform.

Clinical implementation of pharmacogenetics.

PubMed

García-González, Xandra; Cabaleiro, Teresa; Herrero, María José; McLeod, Howard; López-Fernández, Luis A

2016-03-01

In the last decade, pharmacogenetic research has been performed in different fields. However, the application of pharmacogenetic findings to clinical practice has not been as fast as desirable. The current situation of clinical implementation of pharmacogenetics is discussed. This review focuses on the advances of pharmacogenomics to individualize cancer treatments, the relationship between pharmacogenetics and pharmacodynamics in the clinical course of transplant patients receiving a combination of immunosuppressive therapy, the needs and barriers facing pharmacogenetic clinical application, and the situation of pharmacogenetic testing in Spain. It is based on lectures presented by speakers of the Clinical Implementation of Pharmacogenetics Symposium at the VII Conference of the Spanish Pharmacogenetics and Pharmacogenomics Society, held in April 20, 2015.

User-centered design in clinical handover: exploring post-implementation outcomes for clinicians.

PubMed

Wong, Ming Chao; Cummings, Elizabeth; Turner, Paul

2013-01-01

This paper examines the outcomes for clinicians from their involvement in the development of an electronic clinical hand-over tool developed using principles of user-centered design. Conventional e-health post-implementation evaluations tend to emphasize technology-related (mostly positive) outcomes. More recently, unintended (mostly negative) consequences arising from the implementation of e-health technologies have also been reported. There remains limited focus on the post-implementation outcomes for users, particularly those directly involved in e-health design processes. This paper presents detailed analysis and insights into the outcomes experienced post-implementation by a cohort of junior clinicians involved in developing an electronic clinical handover tool in Tasmania, Australia. The qualitative methods used included observations, semi-structured interviews and analysis of clinical handover notes. Significantly, a number of unanticipated flow-on effects were identified that mitigated some of the challenges arising during the design and implementation of the tool. The paper concludes by highlighting the importance of identifying post-implementation user outcomes beyond conventional system adoption and use and also points to the need for more comprehensive evaluative frameworks to encapsulate these broader socio-technical user outcomes.

Healthcare provider education to support integration of pharmacogenomics in practice: the eMERGE Network experience

PubMed Central

Rohrer Vitek, Carolyn R; Abul-Husn, Noura S; Connolly, John J; Hartzler, Andrea L; Kitchner, Terrie; Peterson, Josh F; Rasmussen, Luke V; Smith, Maureen E; Stallings, Sarah; Williams, Marc S; Wolf, Wendy A; Prows, Cynthia A

2017-01-01

Ten organizations within the Electronic Medical Records and Genomics Network developed programs to implement pharmacogenomic sequencing and clinical decision support into clinical settings. Recognizing the importance of informed prescribers, a variety of strategies were used to incorporate provider education to support implementation. Education experiences with pharmacogenomics are described within the context of each organization's prior involvement, including the scope and scale of implementation specific to their Electronic Medical Records and Genomics projects. We describe common and distinct education strategies, provide exemplars and share challenges. Lessons learned inform future perspectives. Future pharmacogenomics clinical implementation initiatives need to include funding toward implementing provider education and evaluating outcomes. PMID:28639489

Measuring Costs to Community-Based Agencies for Implementation of an Evidence-Based Practice.

PubMed

Lang, Jason M; Connell, Christian M

2017-01-01

Healthcare reform has led to an increase in dissemination of evidence-based practices. Cost is frequently cited as a significant yet rarely studied barrier to dissemination of evidence-based practices and the associated improvements in quality of care. This study describes an approach to measuring the incremental, unreimbursed costs in staff time and direct costs to community-based clinics implementing an evidence-based practice through participating in a learning collaborative. Initial implementation costs exceeding those for providing "treatment as usual" were collected for ten clinics implementing trauma-focused cognitive behavioral therapy through participation in 10-month learning collaboratives. Incremental implementation costs of these ten community-based clinic teams averaged the equivalent of US$89,575 (US$ 2012). The most costly activities were training, supervision, preparation time, and implementation team meetings. Recommendations are made for further research on implementation costs, dissemination of evidence-based practices, and implications for researchers and policy makers.

Value for money in changing clinical practice: should decisions about guidelines and implementation strategies be made sequentially or simultaneously?

PubMed

Hoomans, Ties; Severens, Johan L; Evers, Silvia M A A; Ament, Andre J H A

2009-01-01

Decisions about clinical practice change, that is, which guidelines to adopt and how to implement them, can be made sequentially or simultaneously. Decision makers adopting a sequential approach first compare the costs and effects of alternative guidelines to select the best set of guideline recommendations for patient management and subsequently examine the implementation costs and effects to choose the best strategy to implement the selected guideline. In an integral approach, decision makers simultaneously decide about the guideline and the implementation strategy on the basis of the overall value for money in changing clinical practice. This article demonstrates that the decision to use a sequential v. an integral approach affects the need for detailed information and the complexity of the decision analytic process. More importantly, it may lead to different choices of guidelines and implementation strategies for clinical practice change. The differences in decision making and decision analysis between the alternative approaches are comprehensively illustrated using 2 hypothetical examples. We argue that, in most cases, an integral approach to deciding about change in clinical practice is preferred, as this provides more efficient use of scarce health-care resources.

Towards meaningful medication-related clinical decision support: recommendations for an initial implementation.

PubMed

Phansalkar, S; Wright, A; Kuperman, G J; Vaida, A J; Bobb, A M; Jenders, R A; Payne, T H; Halamka, J; Bloomrosen, M; Bates, D W

2011-01-01

Clinical decision support (CDS) can improve safety, quality, and cost-effectiveness of patient care, especially when implemented in computerized provider order entry (CPOE) applications. Medication-related decision support logic forms a large component of the CDS logic in any CPOE system. However, organizations wishing to implement CDS must either purchase the computable clinical content or develop it themselves. Content provided by vendors does not always meet local expectations. Most organizations lack the resources to customize the clinical content and the expertise to implement it effectively. In this paper, we describe the recommendations of a national expert panel on two basic medication-related CDS areas, specifically, drug-drug interaction (DDI) checking and duplicate therapy checking. The goals of this study were to define a starter set of medication-related alerts that healthcare organizations can implement in their clinical information systems. We also draw on the experiences of diverse institutions to highlight the realities of implementing medication decision support. These findings represent the experiences of institutions with a long history in the domain of medication decision support, and the hope is that this guidance may improve the feasibility and efficiency CDS adoption across healthcare settings.

Clinical Evaluation of Normalized Metal Artifact Reduction in kVCT Using MVCT Prior Images (MVCT-NMAR) for Radiation Therapy Treatment Planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paudel, Moti Raj, E-mail: mpaudel@ualberta.ca; Mackenzie, Marc; Fallone, B. Gino

Purpose: To evaluate the metal artifacts in diagnostic kilovoltage computed tomography (kVCT) images of patients that are corrected by use of a normalized metal artifact reduction (NMAR) method with megavoltage CT (MVCT) prior images: MVCT-NMAR. Methods and Materials: MVCT-NMAR was applied to images from 5 patients: 3 with dual hip prostheses, 1 with a single hip prosthesis, and 1 with dental fillings. The corrected images were evaluated for visualization of tissue structures and their interfaces and for radiation therapy dose calculations. They were compared against the corresponding images corrected by the commercial orthopedic metal artifact reduction algorithm in a Phillipsmore » CT scanner. Results: The use of MVCT images for correcting kVCT images in the MVCT-NMAR technique greatly reduces metal artifacts, avoids secondary artifacts, and makes patient images more useful for correct dose calculation in radiation therapy. These improvements are significant, provided the MVCT and kVCT images are correctly registered. The remaining and the secondary artifacts (soft tissue blurring, eroded bones, false bones or air pockets, CT number cupping within the metal) present in orthopedic metal artifact reduction corrected images are removed in the MVCT-NMAR corrected images. A large dose reduction was possible outside the planning target volume (eg, 59.2 Gy to 52.5 Gy in pubic bone) when these MVCT-NMAR corrected images were used in TomoTherapy treatment plans without directional blocks for a prostate cancer patient. Conclusions: The use of MVCT-NMAR corrected images in radiation therapy treatment planning could improve the treatment plan quality for patients with metallic implants.« less

Medical physics aspects of cancer care in the Asia Pacific region

PubMed Central

Kron, T; Cheung, KY; Dai, J; Ravindran, P; Soejoko, D; Inamura, K; Song, JY; Bold, L; Srivastava, R; Rodriguez, L; Wong, TJ; Kumara, A; Lee, CC; Krisanachinda, A; Nguyen, XC; Ng, KH

2008-01-01

Medical physics plays an essential role in modern medicine. This is particularly evident in cancer care where medical physicists are involved in radiotherapy treatment planning and quality assurance as well as in imaging and radiation protection. Due to the large variety of tasks and interests, medical physics is often subdivided into specialties such as radiology, nuclear medicine and radiation oncology medical physics. However, even within their specialty, the role of radiation oncology medical physicists (ROMPs) is diverse and varies between different societies. Therefore, a questionnaire was sent to leading medical physicists in most countries/areas in the Asia/Pacific region to determine the education, role and status of medical physicists. Answers were received from 17 countries/areas representing nearly 2800 radiation oncology medical physicists. There was general agreement that medical physicists should have both academic (typically at MSc level) and clinical (typically at least 2 years) training. ROMPs spent most of their time working in radiotherapy treatment planning (average 17 hours per week); however radiation protection and engineering tasks were also common. Typically, only physicists in large centres are involved in research and teaching. Most respondents thought that the workload of physicists was high, with more than 500 patients per year per physicist, less than one ROMP per two oncologists being the norm, and on average, one megavoltage treatment unit per medical physicist. There was also a clear indication of increased complexity of technology in the region with many countries/areas reporting to have installed helical tomotherapy, IMRT (Intensity Modulated Radiation Therapy), IGRT (Image Guided Radiation Therapy), Gamma-knife and Cyber-knife units. This and the continued workload from brachytherapy will require growing expertise and numbers in the medical physics workforce. Addressing these needs will be an important challenge for the future. PMID:21611001

Evaluating Protocol Lifecycle Time Intervals in HIV/AIDS Clinical Trials

PubMed Central

Schouten, Jeffrey T.; Dixon, Dennis; Varghese, Suresh; Cope, Marie T.; Marci, Joe; Kagan, Jonathan M.

2014-01-01

Background Identifying efficacious interventions for the prevention and treatment of human diseases depends on the efficient development and implementation of controlled clinical trials. Essential to reducing the time and burden of completing the clinical trial lifecycle is determining which aspects take the longest, delay other stages, and may lead to better resource utilization without diminishing scientific quality, safety, or the protection of human subjects. Purpose In this study we modeled time-to-event data to explore relationships between clinical trial protocol development and implementation times, as well as identify potential correlates of prolonged development and implementation. Methods We obtained time interval and participant accrual data from 111 interventional clinical trials initiated between 2006 and 2011 by NIH’s HIV/AIDS Clinical Trials Networks. We determined the time (in days) required to complete defined phases of clinical trial protocol development and implementation. Kaplan-Meier estimates were used to assess the rates at which protocols reached specified terminal events, stratified by study purpose (therapeutic, prevention) and phase group (pilot/phase I, phase II, and phase III/ IV). We also examined several potential correlates to prolonged development and implementation intervals. Results Even though phase grouping did not determine development or implementation times of either therapeutic or prevention studies, overall we observed wide variation in protocol development times. Moreover, we detected a trend toward phase III/IV therapeutic protocols exhibiting longer developmental (median 2 ½ years) and implementation times (>3years). We also found that protocols exceeding the median number of days for completing the development interval had significantly longer implementation. Limitations The use of a relatively small set of protocols may have limited our ability to detect differences across phase groupings. Some timing effects present for a specific study phase may have been masked by combining protocols into phase groupings. Presence of informative censoring, such as withdrawal of some protocols from development if they began showing signs of lost interest among investigators, complicates interpretation of Kaplan-Meier estimates. Because this study constitutes a retrospective examination over an extended period of time, it does not allow for the precise identification of relative factors impacting timing. Conclusions Delays not only increase the time and cost to complete clinical trials, but they also diminish their usefulness by failing to answer research questions in time. We believe that research analyzing the time spent traversing defined intervals across the clinical trial protocol development and implementation continuum can stimulate business process analyses and reengineering efforts that could lead to reductions in the time from clinical trial concept to results, thereby accelerating progress in clinical research. PMID:24980279

Improving outcomes in veterans with oropharyngeal squamous cell carcinoma through implementation of a multidisciplinary clinic.

PubMed

Light, Tyler; Rassi, Edward El; Maggiore, Ronald J; Holland, John; Reed, Julie; Suriano, Kathleen; Stooksbury, Marcelle; Tobin, Nora; Gross, Neil; Clayburgh, Daniel

2017-06-01

Treatment of head and neck cancer is complex, and a multidisciplinary clinic may improve the coordination of care. The value of a head and neck multidisciplinary clinic has not yet been established in oropharyngeal squamous cell carcinoma (SCC). A retrospective review was conducted of Veterans Affairs patients with oropharyngeal SCC undergoing concurrent chemoradiation before and after implementation of the head and neck multidisciplinary clinic. Fifty-two patients before and 54 patients after multidisciplinary clinic were included in this study. Age, tobacco use, and p16+ status were similar between groups. With multidisciplinary clinic, time to treatment decreased, and utilization of supportive services, including speech pathology, dentistry, and nutrition increased. The 5-year disease-specific survival rate increased from 63% to 81% (p = .043) after implementation of the multidisciplinary clinic. Multivariate analysis showed that disease stage (p = .016), p16 status (p = .006), and multidisciplinary clinic participation (p = .042) were predictors of disease-specific survival. Implementation of a multidisciplinary clinic improved care coordination and disease-specific survival in patients with oropharyngeal SCC. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1106-1112, 2017. © 2017 Wiley Periodicals, Inc.

Using systems thinking to support clinical system transformation.

PubMed

Best, Allan; Berland, Alex; Herbert, Carol; Bitz, Jennifer; van Dijk, Marlies W; Krause, Christina; Cochrane, Douglas; Noel, Kevin; Marsden, Julian; McKeown, Shari; Millar, John

2016-05-16

Purpose - The British Columbia Ministry of Health's Clinical Care Management initiative was used as a case study to better understand large-scale change (LSC) within BC's health system. Using a complex system framework, the purpose of this paper is to examine mechanisms that enable and constrain the implementation of clinical guidelines across various clinical settings. Design/methodology/approach - Researchers applied a general model of complex adaptive systems plus two specific conceptual frameworks (realist evaluation and system dynamics mapping) to define and study enablers and constraints. Focus group sessions and interviews with clinicians, executives, managers and board members were validated through an online survey. Findings - The functional themes for managing large-scale clinical change included: creating a context to prepare clinicians for health system transformation initiatives; promoting shared clinical leadership; strengthening knowledge management, strategic communications and opportunities for networking; and clearing pathways through the complexity of a multilevel, dynamic system. Research limitations/implications - The action research methodology was designed to guide continuing improvement of implementation. A sample of initiatives was selected; it was not intended to compare and contrast facilitators and barriers across all initiatives and regions. Similarly, evaluating the results or process of guideline implementation was outside the scope; the methods were designed to enable conversations at multiple levels - policy, management and practice - about how to improve implementation. The study is best seen as a case study of LSC, offering a possible model for replication by others and a tool to shape further dialogue. Practical implications - Recommended action-oriented strategies included engaging local champions; supporting local adaptation for implementation of clinical guidelines; strengthening local teams to guide implementation; reducing change fatigue; ensuring adequate resources; providing consistent communication especially for front-line care providers; and supporting local teams to demonstrate the clinical value of the guidelines to their colleagues. Originality/value - Bringing a complex systems perspective to clinical guideline implementation resulted in a clear understanding of the challenges involved in LSC.

Linked symptom monitoring and depression treatment programmes for specialist cancer services: protocol for a mixed-methods implementation study.

PubMed

Wanat, Marta; Walker, Jane; Burke, Katy; Sevdalis, Nick; Richardson, Alison; Mulick, Amy; Frost, Chris; Sharpe, Michael

2017-07-02

There is growing awareness that cancer services need to address patients' well-being as well as treating their cancer. We developed systematic approaches to (1) monitoring patients' symptoms including depression using a 'Symptom Monitoring Service' and (2) providing treatment for those with major depression using a programme called 'Depression Care for People with Cancer'. Used together, these two programmes were found to be highly effective and cost-effective in clinical trials. The overall aims of this project are to: (1) study the process of introducing these programmes into routine clinical care in a large cancer service, (2) identify the challenges associated with implementation and how these are overcome, (3) determine their effectiveness in a routine non-research setting and (4) describe patients' and clinicians' experience of the programmes. This is a mixed-methods longitudinal implementation study. We will study the process of implementation in three phases (April 2016-December 2018): 'Pre-implementation' (setting up of the new programmes), 'Early Implementation' (implementation of the programmes in a small number of clinics) and 'Implementation and Maintenance' (implementation in the majority of clinics). We will use the following methods of data collection: (1) contemporaneous logs of the implementation process, (2) interviews with healthcare professionals and managers, (3) interviews with patients and (4) routinely collected clinical data. The study has been reviewed by a joint committee of Oxford University Hospitals National Health Service Foundation Trust Research and Development Department and the University of Oxford's Clinical Trials and Research Governance Department and judged to be service evaluation, not requiring ethics committee approval. The findings of this study will guide the scaling up implementation of the programmes across the UK and will enable us to construct an implementation toolkit. We will disseminate our findings in publications and at relevant national and international conferences. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Linked symptom monitoring and depression treatment programmes for specialist cancer services: protocol for a mixed-methods implementation study

PubMed Central

Walker, Jane; Burke, Katy; Sevdalis, Nick; Richardson, Alison; Mulick, Amy; Frost, Chris; Sharpe, Michael

2017-01-01

Introduction There is growing awareness that cancer services need to address patients’ well-being as well as treating their cancer. We developed systematic approaches to (1) monitoring patients’ symptoms including depression using a ‘Symptom Monitoring Service’ and (2) providing treatment for those with major depression using a programme called ‘Depression Care for People with Cancer’. Used together, these two programmes were found to be highly effective and cost-effective in clinical trials. The overall aims of this project are to: (1) study the process of introducing these programmes into routine clinical care in a large cancer service, (2) identify the challenges associated with implementation and how these are overcome, (3) determine their effectiveness in a routine non-research setting and (4) describe patients’ and clinicians’ experience of the programmes. Methods and analysis This is a mixed-methods longitudinal implementation study. We will study the process of implementation in three phases (April 2016–December 2018): ‘Pre-implementation’ (setting up of the new programmes), ‘Early Implementation’ (implementation of the programmes in a small number of clinics) and ‘Implementation and Maintenance’ (implementation in the majority of clinics). We will use the following methods of data collection: (1) contemporaneous logs of the implementation process, (2) interviews with healthcare professionals and managers, (3) interviews with patients and (4) routinely collected clinical data. Ethics and dissemination The study has been reviewed by a joint committee of Oxford University Hospitals National Health Service Foundation Trust Research and Development Department and the University of Oxford’s Clinical Trials and Research Governance Department and judged to be service evaluation, not requiring ethics committee approval. The findings of this study will guide the scaling up implementation of the programmes across the UK and will enable us to construct an implementation toolkit. We will disseminate our findings in publications and at relevant national and international conferences. PMID:28674143

Implementing clinical guidelines for chronic obstructive pulmonary disease: barriers and solutions

PubMed Central

Overington, Jeff D.; Huang, Yao C.; Abramson, Michael J.; Brown, Juliet L.; Goddard, John R.; Bowman, Rayleen V.; Fong, Kwun M.

2014-01-01

Chronic obstructive pulmonary disease (COPD) is a complex chronic lung disease characterised by progressive fixed airflow limitation and acute exacerbations that frequently require hospitalisation. Evidence-based clinical guidelines for the diagnosis and management of COPD are now widely available. However, the uptake of these COPD guidelines in clinical practice is highly variable, as is the case for many other chronic disease guidelines. Studies have identified many barriers to implementation of COPD and other guidelines, including factors such as lack of familiarity with guidelines amongst clinicians and inadequate implementation programs. Several methods for enhancing adherence to clinical practice guidelines have been evaluated, including distribution methods, professional education sessions, electronic health records (EHR), point of care reminders and computer decision support systems (CDSS). Results of these studies are mixed to date, and the most effective ways to implement clinical practice guidelines remain unclear. Given the significant resources dedicated to evidence-based medicine, effective dissemination and implementation of best practice at the patient level is an important final step in the process of guideline development. Future efforts should focus on identifying optimal methods for translating the evidence into everyday clinical practice to ensure that patients receive the best care. PMID:25478199

Standardized patient walkthroughs in the National Drug Abuse Treatment Clinical Trials Network: common challenges to protocol implementation.

PubMed

Fussell, Holly E; Kunkel, Lynn E; McCarty, Dennis; Lewy, Colleen S

2011-09-01

Training research staff to implement clinical trials occurring in community-based addiction treatment programs presents unique challenges. Standardized patient walkthroughs of study procedures may enhance training and protocol implementation. Examine and discuss cross-site and cross-study challenges of participant screening and data collection procedures identified during standardized patient walkthroughs of multi-site clinical trials. Actors portrayed clients and "walked through" study procedures with protocol research staff. The study completed 57 walkthroughs during implementation of 4 clinical trials. Observers and walkthrough participants identified three areas of concern (consent procedures, screening and assessment processes, and protocol implementation) and made suggestions for resolving the concerns. Standardized patient walkthroughs capture issues with study procedures previously unidentified with didactic training or unscripted rehearsals. Clinical trials within the National Drug Abuse Treatment Clinical Trials Network are conducted in addiction treatment centers that vary on multiple dimensions. Based on walkthrough observations, the national protocol team and local site leadership modify standardized operating procedures and resolve cross-site problems prior to recruiting study participants. The standardized patient walkthrough improves consistency across study sites and reduces potential site variation in study outcomes.

Implementing the dynamic appraisal of situational aggression in mental health units.

PubMed

Lantta, Tella; Daffern, Michael; Kontio, Raija; Välimäki, Maritta

2015-01-01

The aims of this study are to explain the intervention of implementing a structured violence risk assessment procedure in mental health inpatient units using the Ottawa Model of Research Use (OMRU) as a guiding framework and to consider nurses' perspectives of its clinical utility and implementation process. Patient aggression toward staff is a global concern in mental health units. The limited extant literature exploring the use of structured violence risk assessments in mental health units, although small and inconsistent, reveals some positive impacts on the incidence of aggression and staff's use of restrictive interventions. Although numerous violence risk assessment instruments have been developed and tested, their systematic implementation and use are still limited. A project titled "Safer Working Management" (111298) was conducted in a Finnish hospital district, across 3 mental health units. The 6 steps of OMRU were followed during implementation of the Dynamic Appraisal of Situational Aggression (DASA). Nurses' views toward structured violence risk assessment procedures varied. Although implementation of the DASA was seen as a useful method to increase discussions with patients and nursing staff, some staff preferred their own clinical judgment for assessment of violence risk. It is possible to use a specific model to promote the implementation of risk assessment instruments in mental health units. However, the complex mental health inpatient environment and the difficulties in understanding and managing aggressive patients present challenges for the implementation of structured violence risk assessment methods. The OMRU provides a tool for clinical nurse specialists to guide implementation process in mental health units. Clinical nurse specialists must promote training for staff regarding use of new innovations, such as the DASA. Implementation processes should be reviewed so that clinical nurse specialists can lead and support mental health staff to properly use structured violence risk assessment measures.

A review of human factors principles for the design and implementation of medication safety alerts in clinical information systems.

PubMed

Phansalkar, Shobha; Edworthy, Judy; Hellier, Elizabeth; Seger, Diane L; Schedlbauer, Angela; Avery, Anthony J; Bates, David W

2010-01-01

The objective of this review is to describe the implementation of human factors principles for the design of alerts in clinical information systems. First, we conduct a review of alarm systems to identify human factors principles that are employed in the design and implementation of alerts. Second, we review the medical informatics literature to provide examples of the implementation of human factors principles in current clinical information systems using alerts to provide medication decision support. Last, we suggest actionable recommendations for delivering effective clinical decision support using alerts. A review of studies from the medical informatics literature suggests that many basic human factors principles are not followed, possibly contributing to the lack of acceptance of alerts in clinical information systems. We evaluate the limitations of current alerting philosophies and provide recommendations for improving acceptance of alerts by incorporating human factors principles in their design.

On implementing clinical decision support: achieving scalability and maintainability by combining business rules and ontologies.

PubMed

Kashyap, Vipul; Morales, Alfredo; Hongsermeier, Tonya

2006-01-01

We present an approach and architecture for implementing scalable and maintainable clinical decision support at the Partners HealthCare System. The architecture integrates a business rules engine that executes declarative if-then rules stored in a rule-base referencing objects and methods in a business object model. The rules engine executes object methods by invoking services implemented on the clinical data repository. Specialized inferences that support classification of data and instances into classes are identified and an approach to implement these inferences using an OWL based ontology engine is presented. Alternative representations of these specialized inferences as if-then rules or OWL axioms are explored and their impact on the scalability and maintenance of the system is presented. Architectural alternatives for integration of clinical decision support functionality with the invoking application and the underlying clinical data repository; and their associated trade-offs are discussed and presented.

Study protocol for "Study of Practices Enabling Implementation and Adaptation in the Safety Net (SPREAD-NET)": a pragmatic trial comparing implementation strategies.

PubMed

Gold, Rachel; Hollombe, Celine; Bunce, Arwen; Nelson, Christine; Davis, James V; Cowburn, Stuart; Perrin, Nancy; DeVoe, Jennifer; Mossman, Ned; Boles, Bruce; Horberg, Michael; Dearing, James W; Jaworski, Victoria; Cohen, Deborah; Smith, David

2015-10-16

Little research has directly compared the effectiveness of implementation strategies in any setting, and we know of no prior trials directly comparing how effectively different combinations of strategies support implementation in community health centers. This paper outlines the protocol of the Study of Practices Enabling Implementation and Adaptation in the Safety Net (SPREAD-NET), a trial designed to compare the effectiveness of several common strategies for supporting implementation of an intervention and explore contextual factors that impact the strategies' effectiveness in the community health center setting. This cluster-randomized trial compares how three increasingly hands-on implementation strategies support adoption of an evidence-based diabetes quality improvement intervention in 29 community health centers, managed by 12 healthcare organizations. The strategies are as follows: (arm 1) a toolkit, presented in paper and electronic form, which includes a training webinar; (arm 2) toolkit plus in-person training with a focus on practice change and change management strategies; and (arm 3) toolkit, in-person training, plus practice facilitation with on-site visits. We use a mixed methods approach to data collection and analysis: (i) baseline surveys on study clinic characteristics, to explore how these characteristics impact the clinics' ability to implement the tools and the effectiveness of each implementation strategy; (ii) quantitative data on change in rates of guideline-concordant prescribing; and (iii) qualitative data on the "how" and "why" underlying the quantitative results. The outcomes of interest are clinic-level results, categorized using the Reach, Effectiveness, Adoption, Implementation, Maintenance (RE-AIM) framework, within an interrupted time-series design with segmented regression models. This pragmatic trial will compare how well each implementation strategy works in "real-world" practices. Having a better understanding of how different strategies support implementation efforts could positively impact the field of implementation science, by comparing practical, generalizable methods for implementing clinical innovations in community health centers. Bridging this gap in the literature is a critical step towards the national long-term goal of effectively disseminating and implementing effective interventions into community health centers. ClinicalTrials.gov, NCT02325531.

Lessons learned from implementing service-oriented clinical decision support at four sites: A qualitative study.

PubMed

Wright, Adam; Sittig, Dean F; Ash, Joan S; Erickson, Jessica L; Hickman, Trang T; Paterno, Marilyn; Gebhardt, Eric; McMullen, Carmit; Tsurikova, Ruslana; Dixon, Brian E; Fraser, Greg; Simonaitis, Linas; Sonnenberg, Frank A; Middleton, Blackford

2015-11-01

To identify challenges, lessons learned and best practices for service-oriented clinical decision support, based on the results of the Clinical Decision Support Consortium, a multi-site study which developed, implemented and evaluated clinical decision support services in a diverse range of electronic health records. Ethnographic investigation using the rapid assessment process, a procedure for agile qualitative data collection and analysis, including clinical observation, system demonstrations and analysis and 91 interviews. We identified challenges and lessons learned in eight dimensions: (1) hardware and software computing infrastructure, (2) clinical content, (3) human-computer interface, (4) people, (5) workflow and communication, (6) internal organizational policies, procedures, environment and culture, (7) external rules, regulations, and pressures and (8) system measurement and monitoring. Key challenges included performance issues (particularly related to data retrieval), differences in terminologies used across sites, workflow variability and the need for a legal framework. Based on the challenges and lessons learned, we identified eight best practices for developers and implementers of service-oriented clinical decision support: (1) optimize performance, or make asynchronous calls, (2) be liberal in what you accept (particularly for terminology), (3) foster clinical transparency, (4) develop a legal framework, (5) support a flexible front-end, (6) dedicate human resources, (7) support peer-to-peer communication, (8) improve standards. The Clinical Decision Support Consortium successfully developed a clinical decision support service and implemented it in four different electronic health records and four diverse clinical sites; however, the process was arduous. The lessons identified by the Consortium may be useful for other developers and implementers of clinical decision support services. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Clinical Chemistry of Patients With Ebola in Monrovia, Liberia.

PubMed

de Wit, Emmie; Kramer, Shelby; Prescott, Joseph; Rosenke, Kyle; Falzarano, Darryl; Marzi, Andrea; Fischer, Robert J; Safronetz, David; Hoenen, Thomas; Groseth, Allison; van Doremalen, Neeltje; Bushmaker, Trenton; McNally, Kristin L; Feldmann, Friederike; Williamson, Brandi N; Best, Sonja M; Ebihara, Hideki; Damiani, Igor A C; Adamson, Brett; Zoon, Kathryn C; Nyenswah, Tolbert G; Bolay, Fatorma K; Massaquoi, Moses; Sprecher, Armand; Feldmann, Heinz; Munster, Vincent J

2016-10-15

The development of point-of-care clinical chemistry analyzers has enabled the implementation of these ancillary tests in field laboratories in resource-limited outbreak areas. The Eternal Love Winning Africa (ELWA) outbreak diagnostic laboratory, established in Monrovia, Liberia, to provide Ebola virus and Plasmodium spp. diagnostics during the Ebola epidemic, implemented clinical chemistry analyzers in December 2014. Clinical chemistry testing was performed for 68 patients in triage, including 12 patients infected with Ebola virus and 18 infected with Plasmodium spp. The main distinguishing feature in clinical chemistry of Ebola virus-infected patients was the elevation in alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyltransferase levels and the decrease in calcium. The implementation of clinical chemistry is probably most helpful when the medical supportive care implemented at the Ebola treatment unit allows for correction of biochemistry derangements and on-site clinical chemistry analyzers can be used to monitor electrolyte balance. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Standardizing terms for clinical pharmacogenetic test results: consensus terms from the Clinical Pharmacogenetics Implementation Consortium (CPIC).

PubMed

Caudle, Kelly E; Dunnenberger, Henry M; Freimuth, Robert R; Peterson, Josh F; Burlison, Jonathan D; Whirl-Carrillo, Michelle; Scott, Stuart A; Rehm, Heidi L; Williams, Marc S; Klein, Teri E; Relling, Mary V; Hoffman, James M

2017-02-01

Reporting and sharing pharmacogenetic test results across clinical laboratories and electronic health records is a crucial step toward the implementation of clinical pharmacogenetics, but allele function and phenotype terms are not standardized. Our goal was to develop terms that can be broadly applied to characterize pharmacogenetic allele function and inferred phenotypes. Terms currently used by genetic testing laboratories and in the literature were identified. The Clinical Pharmacogenetics Implementation Consortium (CPIC) used the Delphi method to obtain a consensus and agree on uniform terms among pharmacogenetic experts. Experts with diverse involvement in at least one area of pharmacogenetics (clinicians, researchers, genetic testing laboratorians, pharmacogenetics implementers, and clinical informaticians; n = 58) participated. After completion of five surveys, a consensus (>70%) was reached with 90% of experts agreeing to the final sets of pharmacogenetic terms. The proposed standardized pharmacogenetic terms will improve the understanding and interpretation of pharmacogenetic tests and reduce confusion by maintaining consistent nomenclature. These standard terms can also facilitate pharmacogenetic data sharing across diverse electronic health care record systems with clinical decision support.Genet Med 19 2, 215-223.

Clinical pharmacogenetics implementation: approaches, successes, and challenges.

PubMed

Weitzel, Kristin W; Elsey, Amanda R; Langaee, Taimour Y; Burkley, Benjamin; Nessl, David R; Obeng, Aniwaa Owusu; Staley, Benjamin J; Dong, Hui-Jia; Allan, Robert W; Liu, J Felix; Cooper-Dehoff, Rhonda M; Anderson, R David; Conlon, Michael; Clare-Salzler, Michael J; Nelson, David R; Johnson, Julie A

2014-03-01

Current challenges exist to widespread clinical implementation of genomic medicine and pharmacogenetics. The University of Florida (UF) Health Personalized Medicine Program (PMP) is a pharmacist-led, multidisciplinary initiative created in 2011 within the UF Clinical Translational Science Institute. Initial efforts focused on pharmacogenetics, with long-term goals to include expansion to disease-risk prediction and disease stratification. Herein we describe the processes for development of the program, the challenges that were encountered and the clinical acceptance by clinicians of the genomic medicine implementation. The initial clinical implementation of the UF PMP began in June 2012 and targeted clopidogrel use and the CYP2C19 genotype in patients undergoing left heart catheterization and percutaneous-coronary intervention (PCI). After 1 year, 1,097 patients undergoing left heart catheterization were genotyped preemptively, and 291 of those underwent subsequent PCI. Genotype results were reported to the medical record for 100% of genotyped patients. Eighty patients who underwent PCI had an actionable genotype, with drug therapy changes implemented in 56 individuals. Average turnaround time from blood draw to genotype result entry in the medical record was 3.5 business days. Seven different third party payors, including Medicare, reimbursed for the test during the first month of billing, with an 85% reimbursement rate for outpatient claims that were submitted in the first month. These data highlight multiple levels of success in clinical implementation of genomic medicine. © 2014 Wiley Periodicals, Inc.

Variations in the implementation and characteristics of chiropractic services in VA.

PubMed

Lisi, Anthony J; Khorsan, Raheleh; Smith, Monica M; Mittman, Brian S

2014-12-01

In 2004, the US Department of Veterans Affairs expanded its delivery of chiropractic care by establishing onsite chiropractic clinics at select facilities across the country. Systematic information regarding the planning and implementation of these clinics and describing their features and performance is lacking. To document the planning, implementation, key features and performance of VA chiropractic clinics, and to identify variations and their underlying causes and key consequences as well as their implications for policy, practice, and research on the introduction of new clinical services into integrated health care delivery systems. Comparative case study of 7 clinics involving site visit-based and telephone-based interviews with 118 key stakeholders, including VA clinicians, clinical leaders and administrative staff, and selected external stakeholders, as well as reviews of key documents and administrative data on clinic performance and service delivery. Interviews were recorded, transcribed, and analyzed using a mixed inductive (exploratory) and deductive approach. Interview data revealed considerable variations in clinic planning and implementation processes and clinic features, as well as perceptions of clinic performance and quality. Administrative data showed high variation in patterns of clinic patient care volume over time. A facility's initial willingness to establish a chiropractic clinic, along with a higher degree of perceived evidence-based and collegial attributes of the facility chiropractor, emerged as key factors associated with higher and more consistent delivery of chiropractic services and higher perceived quality of those services.

Aspects of the Patient-centered Medical Home currently in place: initial findings from preparing the personal physician for practice.

PubMed

Carney, Patricia A; Eiff, M Patrice; Saultz, John W; Douglass, Alan B; Tillotson, Carrie J; Crane, Steven D; Jones, Samuel M; Green, Larry A

2009-10-01

The Patient-centered Medical Home (PCMH) is a central concept in the evolving debate about American health care reform. We studied family medicine residency training programs' continuity clinics to assess baseline status of implementing PCMH components and to compare implementation status between community-based and university training programs. We conducted a survey 24 continuity clinics in 14 residency programs that are part of the Preparing the Personal Physicians for Practice (P(4)) program. We asked questions about aspects of P(4) that had been already implemented at the beginning of the P(4) program. We defined high implementation as aspects that were present in >50% of clinics and low implementation as those present in <50% of clinics. We compared features at university-based and community-based clinics. High areas of implementation were having an electronic health record (EHR), fully secured remote access, electronic patient notes/scheduling/billing, chronic disease management registries, and open-access scheduling. Low areas of implementation included hospital EHR with computerized physician order entry, asynchronous communication with patients, ongoing population-based QA using EHR, use of preventive registries, and practice-based research using EHR. Few differences were noted between university- and community-based residency programs. Many features of the PCMH were already established at baseline in programs participating in P(4).

Implementation of workflow engine technology to deliver basic clinical decision support functionality

PubMed Central

2011-01-01

Background Workflow engine technology represents a new class of software with the ability to graphically model step-based knowledge. We present application of this novel technology to the domain of clinical decision support. Successful implementation of decision support within an electronic health record (EHR) remains an unsolved research challenge. Previous research efforts were mostly based on healthcare-specific representation standards and execution engines and did not reach wide adoption. We focus on two challenges in decision support systems: the ability to test decision logic on retrospective data prior prospective deployment and the challenge of user-friendly representation of clinical logic. Results We present our implementation of a workflow engine technology that addresses the two above-described challenges in delivering clinical decision support. Our system is based on a cross-industry standard of XML (extensible markup language) process definition language (XPDL). The core components of the system are a workflow editor for modeling clinical scenarios and a workflow engine for execution of those scenarios. We demonstrate, with an open-source and publicly available workflow suite, that clinical decision support logic can be executed on retrospective data. The same flowchart-based representation can also function in a prospective mode where the system can be integrated with an EHR system and respond to real-time clinical events. We limit the scope of our implementation to decision support content generation (which can be EHR system vendor independent). We do not focus on supporting complex decision support content delivery mechanisms due to lack of standardization of EHR systems in this area. We present results of our evaluation of the flowchart-based graphical notation as well as architectural evaluation of our implementation using an established evaluation framework for clinical decision support architecture. Conclusions We describe an implementation of a free workflow technology software suite (available at http://code.google.com/p/healthflow) and its application in the domain of clinical decision support. Our implementation seamlessly supports clinical logic testing on retrospective data and offers a user-friendly knowledge representation paradigm. With the presented software implementation, we demonstrate that workflow engine technology can provide a decision support platform which evaluates well against an established clinical decision support architecture evaluation framework. Due to cross-industry usage of workflow engine technology, we can expect significant future functionality enhancements that will further improve the technology's capacity to serve as a clinical decision support platform. PMID:21477364

Development and assessment of an active strategy for the implementation of a collaborative care approach for depression in primary care (the INDI·i project).

PubMed

Aragonès, Enric; Palao, Diego; López-Cortacans, Germán; Caballero, Antonia; Cardoner, Narcís; Casaus, Pilar; Cavero, Myriam; Monreal, José Antonio; Pérez-Sola, Víctor; Cirera, Miquel; Loren, Maite; Bellerino, Eva; Tomé-Pires, Catarina; Palacios, Laura

2017-12-13

Primary care is the principal clinical setting for the management of depression. However, significant shortcomings have been detected in its diagnosis and clinical management, as well as in patient outcomes. We developed the INDI collaborative care model to improve the management of depression in primary care. This intervention has been favorably evaluated in terms of clinical efficacy and cost-effectiveness in a clinical trial. Our aim is to bring this intervention from the scientific context into clinical practice. Objective: To test for the feasibility and impact of a strategy for implementing the INDI model for depression in primary care. A quasi-experiment conducted in primary care. Several areas will be established to implement the new program and other, comparable areas will serve as control group. The study constitutes the preliminary phase preceding generalization of the model in the Catalan public healthcare system. The target population of the intervention are patients with major depression. The implementation strategy will also involve healthcare professionals, primary care centers, as well as management departments and the healthcare organization itself in the geographical areas where the study will be conducted: Camp de Tarragona and Vallès Occidental (Catalonia). The INDI model is a program for improving the management of depression involving clinical, instructional, and organizational interventions including the participation of nurses as care managers, the efficacy and efficiency of which has been proven in a clinical trial. We will design an active implementation strategy for this model based on the PARIHS (Promoting Action on Research Implementation in Health Services) framework. Qualitative and quantitative measures will be used to evaluate variables related to the successful implementation of the model: acceptability, utility, penetration, sustainability, and clinical impact. This project tests the transferability of a healthcare intervention supported by scientific research to clinical practice. If implementation is successful in this experimental phase, we will use the information and experience obtained to propose and plan the generalization of the INDI model for depression in the Catalan healthcare system. We expect the program to benefit patients, the healthcare system, and society. ClinicalTrials.gov identifier: NCT03285659 ; Registered 12th September, 2017.

User involvement in the implementation of clinical guidelines for common mental health disorders: a review and compilation of strategies and resources.

PubMed

Moreno, Eliana M; Moriana, Juan Antonio

2016-08-09

There is now broad consensus regarding the importance of involving users in the process of implementing guidelines. Few studies, however, have addressed this issue, let alone the implementation of guidelines for common mental health disorders. The aim of this study is to compile and describe implementation strategies and resources related to common clinical mental health disorders targeted at service users. The literature was reviewed and resources for the implementation of clinical guidelines were compiled using the PRISMA model. A mixed qualitative and quantitative analysis was performed based on a series of categories developed ad hoc. A total of 263 items were included in the preliminary analysis and 64 implementation resources aimed at users were analysed in depth. A wide variety of types, sources and formats were identified, including guides (40%), websites (29%), videos and leaflets, as well as instruments for the implementation of strategies regarding information and education (64%), self-care, or users' assessment of service quality. The results reveal the need to establish clear criteria for assessing the quality of implementation materials in general and standardising systems to classify user-targeted strategies. The compilation and description of key elements of strategies and resources for users can be of interest in designing materials and specific actions for this target audience, as well as improving the implementation of clinical guidelines.

Clinical Actionability of Comprehensive Genomic Profiling for Management of Rare or Refractory Cancers

PubMed Central

Hirshfield, Kim M.; Tolkunov, Denis; Zhong, Hua; Ali, Siraj M.; Stein, Mark N.; Murphy, Susan; Vig, Hetal; Vazquez, Alexei; Glod, John; Moss, Rebecca A.; Belyi, Vladimir; Chan, Chang S.; Chen, Suzie; Goodell, Lauri; Foran, David; Yelensky, Roman; Palma, Norma A.; Sun, James X.; Miller, Vincent A.; Stephens, Philip J.; Ross, Jeffrey S.; Kaufman, Howard; Poplin, Elizabeth; Mehnert, Janice; Tan, Antoinette R.; Bertino, Joseph R.; Aisner, Joseph; DiPaola, Robert S.

2016-01-01

Background. The frequency with which targeted tumor sequencing results will lead to implemented change in care is unclear. Prospective assessment of the feasibility and limitations of using genomic sequencing is critically important. Methods. A prospective clinical study was conducted on 100 patients with diverse-histology, rare, or poor-prognosis cancers to evaluate the clinical actionability of a Clinical Laboratory Improvement Amendments (CLIA)-certified, comprehensive genomic profiling assay (FoundationOne), using formalin-fixed, paraffin-embedded tumors. The primary objectives were to assess utility, feasibility, and limitations of genomic sequencing for genomically guided therapy or other clinical purpose in the setting of a multidisciplinary molecular tumor board. Results. Of the tumors from the 92 patients with sufficient tissue, 88 (96%) had at least one genomic alteration (average 3.6, range 0–10). Commonly altered pathways included p53 (46%), RAS/RAF/MAPK (rat sarcoma; rapidly accelerated fibrosarcoma; mitogen-activated protein kinase) (45%), receptor tyrosine kinases/ligand (44%), PI3K/AKT/mTOR (phosphatidylinositol-4,5-bisphosphate 3-kinase; protein kinase B; mammalian target of rapamycin) (35%), transcription factors/regulators (31%), and cell cycle regulators (30%). Many low frequency but potentially actionable alterations were identified in diverse histologies. Use of comprehensive profiling led to implementable clinical action in 35% of tumors with genomic alterations, including genomically guided therapy, diagnostic modification, and trigger for germline genetic testing. Conclusion. Use of targeted next-generation sequencing in the setting of an institutional molecular tumor board led to implementable clinical action in more than one third of patients with rare and poor-prognosis cancers. Major barriers to implementation of genomically guided therapy were clinical status of the patient and drug access. Early and serial sequencing in the clinical course and expanded access to genomically guided early-phase clinical trials and targeted agents may increase actionability. Implications for Practice: Identification of key factors that facilitate use of genomic tumor testing results and implementation of genomically guided therapy may lead to enhanced benefit for patients with rare or difficult to treat cancers. Clinical use of a targeted next-generation sequencing assay in the setting of an institutional molecular tumor board led to implementable clinical action in over one third of patients with rare and poor prognosis cancers. The major barriers to implementation of genomically guided therapy were clinical status of the patient and drug access both on trial and off label. Approaches to increase actionability include early and serial sequencing in the clinical course and expanded access to genomically guided early phase clinical trials and targeted agents. PMID:27566247

Healthcare professionals’ perceptions of clinical governance implementation: a qualitative New Zealand study of 3205 open-ended survey comments

PubMed Central

Gauld, Robin; Horsburgh, Simon

2015-01-01

Objectives To investigate healthcare professional perceptions of local implementation of a national clinical governance policy in New Zealand. Design Respondent comments written at the end of a national healthcare professional survey designed to assess implementation of core components of the clinical governance policy. Setting The written comments were provided by respondents to a survey distributed to over 41 000 registered healthcare professionals employed in 19 of New Zealand's government-funded District Health Boards. Comments were analysed and categorised within emerging themes. Results 3205 written comments were received. Five key themes illustrating barriers to clinical governance implementation were found, representing problems with: developing management–clinical relations; clinicians stepping up into clinical governance and leadership activities; interprofessional relations; training needs for governance and leadership; and having insufficient time to get involved. Conclusions Despite a national policy on clinical governance which New Zealand's government launched in 2009, this study found that considerable effort is required to build clinical governance at the local level. This finding parallels with other studies in the field. Two areas demand attention: building systems for organisational governance and leadership; and building professional governance arrangements. PMID:25564142

How are evidence and knowledge used in orthopaedic decision-making? Three comparative case studies of different approaches to implementation of clinical guidance in practice.

PubMed

Grove, Amy; Clarke, Aileen; Currie, Graeme

2018-05-31

The uptake and use of clinical guidelines is often insufficient to change clinical behaviour and reduce variation in practice. As a consequence of diverse organisational contexts, the simple provision of guidelines cannot ensure fidelity or guarantee their use when making decisions. Implementation research in surgery has focused on understanding what evidence exists for clinical practice decisions but limits understanding to the technical, educational and accessibility issues. This research aims to identify where, when and how evidence and knowledge are used in orthopaedic decision-making and how variation in these factors contributes to different approaches to implementation of clinical guidance in practice. We used in-depth case studies to examine guideline implementation in real-life surgical practice. We conducted comparative case studies in three English National Health Service hospitals over a 12-month period. Each in-depth case study consisted of a mix of qualitative methods including interviews, observations and document analysis. Data included field notes from observations of day-to-day practice, 64 interviews with NHS surgeons and staff and the collection of 121 supplementary documents. Case studies identified 17 sources of knowledge and evidence which influenced clinical decisions in elective orthopaedic surgery. A comparative analysis across cases revealed that each hospital had distinct approaches to decision-making. Decision-making is described as occurring as a result of how 17 types of knowledge and evidence were privileged and of how they interacted and changed in context. Guideline implementation was contingent and mediated through four distinct contextual levels. Implementation could be assessed for individual surgeons, groups of surgeons or the organisation as a whole, but it could also differ between these levels. Differences in how evidence and knowledge were used contributed to variations in practice from guidelines. A range of complex and competing sources of evidence and knowledge exists which influence the working practices of healthcare professionals. The dynamic selection, combination and use of each type of knowledge and evidence influence the implementation and use of clinical guidance in practice. Clinical guidelines are a fundamental part of practice, but represent only one type of evidence influencing clinical decisions. In the orthopaedic speciality, other distinct sources of evidence and knowledge are selected and used which impact on how guidelines are implemented. New approaches to guideline implementation need to appreciate and incorporate this diverse range of knowledge and evidence which influences clinical decisions and to take account of the changing contexts in which decisions are made.

Development, implementation and evaluation of a clinical research engagement and leadership capacity building program in a large Australian health care service.

PubMed

Misso, Marie L; Ilic, Dragan; Haines, Terry P; Hutchinson, Alison M; East, Christine E; Teede, Helena J

2016-01-14

Health professionals need to be integrated more effectively in clinical research to ensure that research addresses clinical needs and provides practical solutions at the coal face of care. In light of limited evidence on how best to achieve this, evaluation of strategies to introduce, adapt and sustain evidence-based practices across different populations and settings is required. This project aims to address this gap through the co-design, development, implementation, evaluation, refinement and ultimately scale-up of a clinical research engagement and leadership capacity building program in a clinical setting with little to no co-ordinated approach to clinical research engagement and education. The protocol is based on principles of research capacity building and on a six-step framework, which have previously led to successful implementation and long-term sustainability. A mixed methods study design will be used. Methods will include: (1) a review of the literature about strategies that engage health professionals in research through capacity building and/or education in research methods; (2) a review of existing local research education and support elements; (3) a needs assessment in the local clinical setting, including an online cross-sectional survey and semi-structured interviews; (4) co-design and development of an educational and support program; (5) implementation of the program in the clinical environment; and (6) pre- and post-implementation evaluation and ultimately program scale-up. The evaluation focuses on research activity and knowledge, attitudes and preferences about clinical research, evidence-based practice and leadership and post implementation, about their satisfaction with the program. The investigators will evaluate the feasibility and effect of the program according to capacity building measures and will revise where appropriate prior to scale-up. It is anticipated that this clinical research engagement and leadership capacity building program will enable and enhance clinically relevant research to be led and conducted by health professionals in the health setting. This approach will also encourage identification of areas of clinical uncertainty and need that can be addressed through clinical research within the health setting.

Organizational Correlates of Implementation of Colocation of Mental Health and Primary Care in the Veterans Health Administration

PubMed Central

Guerrero, Erick G.; Heslin, Kevin C.; Chang, Evelyn; Fenwick, Karissa; Yano, Elizabeth

2014-01-01

This study explored the role of organizational factors in the ability of Veterans Health Administration (VHA) clinics to implement colocated mental health care in primary care settings (PC-MH). The study used data from the VHA Clinical Practice Organizational Survey collected in 2007 from 225 clinic administrators across the United States. Clinic degree of implementation of PC-MH was the dependent variable, whereas independent variables included policies and procedures, organizational context, and leaders’ perceptions of barriers to change. Pearson bivariate correlations and multivariable linear regression were used to test hypotheses. Results show that depression care training for primary care providers and clinics’ flexibility and participation were both positively correlated with implementation of PC-MH. However, after accounting for other factors, regressions show that only training primary care providers in depression care was marginally associated with degree of implementation of PC-MH (p = 0.051). Given the importance of this topic for implementing integrated care as part of health care reform, these null findings underscore the need to improve theory and testing of more proximal measures of colocation in future work. PMID:25096986

From the Editor: An Introduction to the JSLHR Supplement on Implementation Science.

PubMed

Paul, Rhea

2015-12-01

The JSLHR Supplement on Implementation Science is aimed at providing discussion and examples of research in implementation science, the study of methods designed to promote the incorporation of research findings into clinical practice. Practitioners in the language science area were invited to submit articles that address their experience with various aspects of implementation science. Six articles from several research groups comprise this supplement. Implementation science is an aspect of intervention research that merits consideration by communication disorders scientists. More extensive practice of implementation science will improve uptake of evidence-based practice in the clinical community.

[Importance of clinical trial design and standardized implementation in ophthalmology].

PubMed

Xu, Xun

2013-06-01

Clinical trial is an important medical research method, as well as the bridge of translational medicine. The results of scientific evidences are useful to make clinical practice guidelines. At present,much experience of carrying out ophthalmology clinical trials has been obtained and achieved, but there are still some scientific, practical and ethical problems to be solved,because of their impact on the authenticity and reliability of the results. Therefore, attaching great importance to design of the clinical research and implement of the standardization would be the goal and the development direction. Clinical trial design rely on objective, follow international design principles on the ethics,randomization, blinding and placebo setting. During the trial implementation, personnel training,project management and monitoring would help to reduce protocol deviation and ensure data authenticity.

Predicting Recovery Potential for Individual Stroke Patients Increases Rehabilitation Efficiency.

PubMed

Stinear, Cathy M; Byblow, Winston D; Ackerley, Suzanne J; Barber, P Alan; Smith, Marie-Claire

2017-04-01

Several clinical measures and biomarkers are associated with motor recovery after stroke, but none are used to guide rehabilitation for individual patients. The objective of this study was to evaluate the implementation of upper limb predictions in stroke rehabilitation, by combining clinical measures and biomarkers using the Predict Recovery Potential (PREP) algorithm. Predictions were provided for patients in the implementation group (n=110) and withheld from the comparison group (n=82). Predictions guided rehabilitation therapy focus for patients in the implementation group. The effects of predictive information on clinical practice (length of stay, therapist confidence, therapy content, and dose) were evaluated. Clinical outcomes (upper limb function, impairment and use, independence, and quality of life) were measured 3 and 6 months poststroke. The primary clinical practice outcome was inpatient length of stay. The primary clinical outcome was Action Research Arm Test score 3 months poststroke. Length of stay was 1 week shorter for the implementation group (11 days; 95% confidence interval, 9-13 days) than the comparison group (17 days; 95% confidence interval, 14-21 days; P =0.001), controlling for upper limb impairment, age, sex, and comorbidities. Therapists were more confident ( P =0.004) and modified therapy content according to predictions for the implementation group ( P <0.05). The algorithm correctly predicted the primary clinical outcome for 80% of patients in both groups. There were no adverse effects of algorithm implementation on patient outcomes at 3 or 6 months poststroke. PREP algorithm predictions modify therapy content and increase rehabilitation efficiency after stroke without compromising clinical outcome. URL: http://anzctr.org.au. Unique identifier: ACTRN12611000755932. © 2017 American Heart Association, Inc.

Adoption and implementation of a computer-delivered HIV/STD risk-reduction intervention for African American adolescent females seeking services at county health departments: implementation optimization is urgently needed.

PubMed

DiClemente, Ralph J; Bradley, Erin; Davis, Teaniese L; Brown, Jennifer L; Ukuku, Mary; Sales, Jessica M; Rose, Eve S; Wingood, Gina M

2013-06-01

Although group-delivered HIV/sexually transmitted disease (STD) risk-reduction interventions for African American adolescent females have proven efficacious, they require significant financial and staffing resources to implement and may not be feasible in personnel- and resource-constrained public health clinics. We conducted a study assessing adoption and implementation of an evidence-based HIV/STD risk-reduction intervention that was translated from a group-delivered modality to a computer-delivered modality to facilitate use in county public health departments. Usage of the computer-delivered intervention was low across 8 participating public health clinics. Further investigation is needed to optimize implementation by identifying, understanding, and surmounting barriers that hamper timely and efficient implementation of technology-delivered HIV/STD risk-reduction interventions in county public health clinics.

Adoption and Implementation of a Computer-delivered HIV/STD Risk-Reduction Intervention for African American Adolescent Females Seeking Services at County Health Departments: Implementation Optimization is Urgently Needed

PubMed Central

DiClemente, Ralph J.; Bradley, Erin; Davis, Teaniese L.; Brown, Jennifer L.; Ukuku, Mary; Sales, Jessica M.; Rose, Eve S.; Wingood, Gina M.

2013-01-01

Although group-delivered HIV/STD risk-reduction interventions for African American adolescent females have proven efficacious, they require significant financial and staffing resources to implement and may not be feasible in personnel- and resource-constrained public health clinics. We conducted a study assessing adoption and implementation of an evidence-based HIV/STD risk-reduction intervention that was translated from a group-delivered modality to a computer-delivered modality to facilitate use in county public health departments. Usage of the computer-delivered intervention was low across eight participating public health clinics. Further investigation is needed to optimize implementation by identifying, understanding and surmounting barriers that hamper timely and efficient implementation of technology-delivered HIV/STD risk-reduction interventions in county public health clinics. PMID:23673891

A Systematic Review of Strategies for Implementing Empirically Supported Mental Health Interventions

PubMed Central

Powell, Byron J.; Proctor, Enola K.; Glass, Joseph E.

2013-01-01

Objective This systematic review examines experimental studies that test the effectiveness of strategies intended to integrate empirically supported mental health interventions into routine care settings. Our goal was to characterize the state of the literature and to provide direction for future implementation studies. Methods A literature search was conducted using electronic databases and a manual search. Results Eleven studies were identified that tested implementation strategies with a randomized (n = 10) or controlled clinical trial design (n = 1). The wide range of clinical interventions, implementation strategies, and outcomes evaluated precluded meta-analysis. However, the majority of studies (n = 7; 64%) found a statistically significant effect in the hypothesized direction for at least one implementation or clinical outcome. Conclusions There is a clear need for more rigorous research on the effectiveness of implementation strategies, and we provide several suggestions that could improve this research area. PMID:24791131

Clinical bacteriology in low-resource settings: today's solutions.

PubMed

Ombelet, Sien; Ronat, Jean-Baptiste; Walsh, Timothy; Yansouni, Cedric P; Cox, Janneke; Vlieghe, Erika; Martiny, Delphine; Semret, Makeda; Vandenberg, Olivier; Jacobs, Jan

2018-03-05

Low-resource settings are disproportionately burdened by infectious diseases and antimicrobial resistance. Good quality clinical bacteriology through a well functioning reference laboratory network is necessary for effective resistance control, but low-resource settings face infrastructural, technical, and behavioural challenges in the implementation of clinical bacteriology. In this Personal View, we explore what constitutes successful implementation of clinical bacteriology in low-resource settings and describe a framework for implementation that is suitable for general referral hospitals in low-income and middle-income countries with a moderate infrastructure. Most microbiological techniques and equipment are not developed for the specific needs of such settings. Pending the arrival of a new generation diagnostics for these settings, we suggest focus on improving, adapting, and implementing conventional, culture-based techniques. Priorities in low-resource settings include harmonised, quality assured, and tropicalised equipment, consumables, and techniques, and rationalised bacterial identification and testing for antimicrobial resistance. Diagnostics should be integrated into clinical care and patient management; clinically relevant specimens must be appropriately selected and prioritised. Open-access training materials and information management tools should be developed. Also important is the need for onsite validation and field adoption of diagnostics in low-resource settings, with considerable shortening of the time between development and implementation of diagnostics. We argue that the implementation of clinical bacteriology in low-resource settings improves patient management, provides valuable surveillance for local antibiotic treatment guidelines and national policies, and supports containment of antimicrobial resistance and the prevention and control of hospital-acquired infections. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of Clinical Decision Topic on Patients' Involvement in and Satisfaction With Decisions and Their Subsequent Implementation.

PubMed

Freidl, Marion; Pesola, Francesca; Konrad, Jana; Puschner, Bernd; Kovacs, Attila Istvan; De Rosa, Corrado; Fiorillo, Andrea; Krogsgaard Bording, Malene; Kawohl, Wolfram; Rössler, Wulf; Nagy, Marietta; Munk-Jørgensen, Povl; Slade, Mike

2016-06-01

Clinical decision making is an important aspect of mental health care. Predictors of how patients experience decision making and whether decisions are implemented are underresearched. This study investigated the relationship between decision topic and involvement in the decision, satisfaction with it, and its subsequent implementation from both staff and patient perspectives. As part of the Clinical Decision Making and Outcome in Routine Care for People With Severe Mental Illness study, patients (N=588) and their providers (N=213) were recruited from community-based mental health services in six European countries. Both completed bimonthly assessments for one year using the Clinical Decision Making in Routine Care Scale to assess the decision topic and implementation; both also completed the Clinical Decision Making Involvement and Satisfaction Scale. Three categories of decision topics were determined: treatment (most frequently cited), social, and financial. The topic identified as most important remained stable over the follow-up. Patients were more likely to rate their involvement as active rather than passive for social decisions (odds ratio [OR]=5.7, p<.001) and financial decisions (OR=9.5, p<.001). They were more likely to report higher levels of satisfaction rather than lower levels for social decisions (OR=1.5, p=.01) and financial decisions (OR=1.7, p=.01). Social decisions were more likely to be partly implemented (OR=3.0, p<.001) or fully implemented (OR=1.7, p=.03) than not implemented. Patients reported poorer involvement, satisfaction, and implementation in regard to treatment-related decisions, compared with social and financial decisions. Clinicians may need to employ different interactional styles for different types of decisions to maximize satisfaction and decision implementation.

Excerpts from the 1st international NTNU symposium on current and future clinical biomarkers of cancer: innovation and implementation, June 16th and 17th 2016, Trondheim, Norway.

PubMed

Robles, Ana I; Olsen, Karina Standahl; Tsui, Dana W T; Georgoulias, Vassilis; Creaney, Jenette; Dobra, Katalin; Vyberg, Mogens; Minato, Nagahiro; Anders, Robert A; Børresen-Dale, Anne-Lise; Zhou, Jianwei; Sætrom, Pål; Nielsen, Boye Schnack; Kirschner, Michaela B; Krokan, Hans E; Papadimitrakopoulou, Vassiliki; Tsamardinos, Ioannis; Røe, Oluf D

2016-10-19

The goal of biomarker research is to identify clinically valid markers. Despite decades of research there has been disappointingly few molecules or techniques that are in use today. The "1st International NTNU Symposium on Current and Future Clinical Biomarkers of Cancer: Innovation and Implementation", was held June 16th and 17th 2016, at the Knowledge Center of the St. Olavs Hospital in Trondheim, Norway, under the auspices of the Norwegian University of Science and Technology (NTNU) and the HUNT biobank and research center. The Symposium attracted approximately 100 attendees and invited speakers from 12 countries and 4 continents. In this Symposium original research and overviews on diagnostic, predictive and prognostic cancer biomarkers in serum, plasma, urine, pleural fluid and tumor, circulating tumor cells and bioinformatics as well as how to implement biomarkers in clinical trials were presented. Senior researchers and young investigators presented, reviewed and vividly discussed important new developments in the field of clinical biomarkers of cancer, with the goal of accelerating biomarker research and implementation. The excerpts of this symposium aim to give a cutting-edge overview and insight on some highly important aspects of clinical cancer biomarkers to-date to connect molecular innovation with clinical implementation to eventually improve patient care.

Implementing Peer Learning in Clinical Education: A Framework to Address Challenges In the "Real World".

PubMed

Tai, Joanna Hong Meng; Canny, Benedict J; Haines, Terry P; Molloy, Elizabeth K

2017-01-01

Phenomenon: Peer learning has many benefits and can assist students in gaining the educational skills required in future years when they become teachers themselves. Peer learning may be particularly useful in clinical learning environments, where students report feeling marginalized, overwhelmed, and unsupported. Educational interventions often fail in the workplace environment, as they are often conceived in the "ideal" rather than the complex, messy real world. This work sought to explore barriers and facilitators to implementing peer learning activities in a clinical curriculum. Previous peer learning research results and a matrix of empirically derived peer learning activities were presented to local clinical education experts to generate discussion around the realities of implementing such activities. Potential barriers and limitations of and strategies for implementing peer learning in clinical education were the focus of the individual interviews. Thematic analysis of the data identified three key considerations for real-world implementation of peer learning: culture, epistemic authority, and the primacy of patient-centered care. Strategies for peer learning implementation were also developed from themes within the data, focusing on developing a culture of safety in which peer learning could be undertaken, engaging both educators and students, and establishing expectations for the use of peer learning. Insights: This study identified considerations and strategies for the implementation of peer learning activities, which took into account both educator and student roles. Reported challenges were reflective of those identified within the literature. The resultant framework may aid others in anticipating implementation challenges. Further work is required to test the framework's application in other contexts and its effect on learner outcomes.

Description of a Standardized Treatment Center that Utilizes Evidence-Based Clinic Operations to Facilitate Implementation of an Evidence-Based Treatment

ERIC Educational Resources Information Center

Donohue, Brad; Allen, Daniel N.; Romero, Valerie; Hill, Heather H.; Vasaeli, Kathryn; Lapota, Holly; Tracy, Kendra; Gorney, Suzanne; Abdel-al, Ruweida; Caldas, Diana; Herdzik, Karen; Bradshaw, Kelsey; Valdez, Robby; Van Hasselt, Vincent B.

2009-01-01

Developers of evidence-based therapies are enhancing methods of teaching therapists to implement "best practices" with integrity. However, there is a relative dearth of information available as to clinic operations and related contextual factors necessary to sustain successful implementation of these treatments. This article describes various…

Improved continuity of care in a resident clinic.

PubMed

Butler, Melissa; Kim, Hyungkoo; Sansone, Randy

2017-02-01

For residents in the out-patient clinic, continuity in patient care is an integral and vital aspect of internal medicine training, but is frequently compromised by resident in-patient schedules, the structure of the out-patient clinic and the need to comply with the increasing regulation of duty hours. In this study, we examined whether the creation and implementation of a new team approach, the Firms Model, would improve the continuity of patient care in the internal medicine resident out-patient clinic. Before the implementation of the Firms Model, an examination of a consecutive clinic sample indicated that patients were seen by their assigned resident providers 41.9 per cent of the time (n = 1319 clinic visits). After implementation of the Firms Model, an examination of a consecutive clinic sample indicated that patients were seen by their assigned Firm resident providers 88.9 per cent of the time (n = 1341 clinic visits). Implementation of the Firms Model resulted in a statistically significant increase in the percentage of patients seen by assigned resident providers in an internal medicine out-patient clinic, culminating in a substantial improvement in continuity of care within our resident out-patient clinic. We discuss the implications of these findings. Continuity in patient care is an integral and vital aspect of internal medicine training, but is frequently compromised. © 2016 John Wiley & Sons Ltd.

Patient-Provider Communication: Does Electronic Messaging Reduce Incoming Telephone Calls?

PubMed

Dexter, Eve N; Fields, Scott; Rdesinski, Rebecca E; Sachdeva, Bhavaya; Yamashita, Daisuke; Marino, Miguel

2016-01-01

Internet-based patient portals are increasingly being implemented throughout health care organizations to enhance health and optimize communication between patients and health professionals. The decision to adopt a patient portal requires careful examination of the advantages and disadvantages of implementation. This study aims to investigate 1 proposed advantage of implementation: alleviating some of the clinical workload faced by employees. A retrospective time-series analysis of the correlation between the rate of electronic patient-to-provider messages-a common attribute of Internet-based patient portals-and incoming telephone calls. The rate of electronic messages and incoming telephone calls were monitored from February 2009 to June 2014 at 4 economically diverse clinics (a federally qualified health center, a rural health clinic, a community-based clinic, and a university-based clinic) related to 1 university hospital. All 4 clinics showed an increase in the rate of portal use as measured by electronic patient-to-provider messaging during the study period. Electronic patient-to-provider messaging was significantly positively correlated with incoming telephone calls at 2 of the clinics (r = 0.546, P < .001 and r = 0.543, P < .001). The remaining clinics were not significantly correlated but demonstrated a weak positive correlation (r = 0.098, P = .560 and r = 0.069, P = .671). Implementation and increased use of electronic patient-to-provider messaging was associated with increased use of telephone calls in 2 of the study clinics. While practices are increasingly making the decision of whether to implement a patient portal as part of their system of care, it is important that the motivation behind such a change not be based on the idea that it will alleviate clinical workload. © Copyright 2016 by the American Board of Family Medicine.

Implementation of a Telephone Postoperative Clinic in an Integrated Health System.

PubMed

Kummerow Broman, Kristy; Roumie, Christianne L; Stewart, Melissa K; Castellanos, Jason A; Tarpley, John L; Dittus, Robert S; Pierce, Richard A

2016-10-01

Earlier work suggested that telephone follow-up could be used in lieu of in-person follow-up after surgery, saving patients time and travel and maximizing use of scarce surgeon and facility resources. We report our experience implementing and evaluating telephone postoperative follow-up within an integrated health system. We conducted a pre-post evaluation of a general surgery telephone postoperative clinic at a tertiary care Veterans Affairs facility from April 2015 to February 2016. Patients were offered a telephone postoperative visit from a surgical provider in lieu of an in-person clinic visit. Telephone clinic operating procedures were refined through iterative cycles of change using the Plan-Do-Study-Act method. The study period included 2 months pre-intervention and 9 months post-intervention. The primary end point was mean number of clinic visits per eligible patient before and after telephone clinic implementation. Secondary outcomes were rates of emergency department visits and readmissions before vs after telephone clinic implementation and complication rates in patients scheduled for telephone vs in-person postoperative care. During the study period, 200 patients underwent eligible operations, 29 pre-intervention and 171 post-intervention. In-person clinic use decreased from 0.83 visits per eligible patient pre-intervention to 0.40 after implementation of the telephone clinic (p < 0.01). There was no difference in rates of emergency department presentation or readmission in eligible patients (0.17 visits/patient pre-intervention vs 0.12 post-intervention; p = 0.36). Complication rates were comparable for eligible patients who were and were not scheduled for telephone care (6% vs 8%; p = 0.31). Telephone postoperative care can be used in select populations as a triage tool to identify patients who require in-person care and decrease overall in-person clinic use. Published by Elsevier Inc.

Implementing community-based provider participation in research: an empirical study.

PubMed

Teal, Randall; Bergmire, Dawn M; Johnston, Matthew; Weiner, Bryan J

2012-05-08

Since 2003, the United States National Institutes of Health (NIH) has sought to restructure the clinical research enterprise in the United States by promoting collaborative research partnerships between academically-based investigators and community-based physicians. By increasing community-based provider participation in research (CBPPR), the NIH seeks to advance the science of discovery by conducting research in clinical settings where most people get their care, and accelerate the translation of research results into everyday clinical practice. Although CBPPR is seen as a promising strategy for promoting the use of evidence-based clinical services in community practice settings, few empirical studies have examined the organizational factors that facilitate or hinder the implementation of CBPPR. The purpose of this study is to explore the organizational start-up and early implementation of CBPPR in community-based practice. We used longitudinal, case study research methods and an organizational model of innovation implementation to theoretically guide our study. Our sample consisted of three community practice settings that recently joined the National Cancer Institute's (NCI) Community Clinical Oncology Program (CCOP) in the United States. Data were gathered through site visits, telephone interviews, and archival documents from January 2008 to May 2011. The organizational model for innovation implementation was useful in identifying and investigating the organizational factors influencing start-up and early implementation of CBPPR in CCOP organizations. In general, the three CCOP organizations varied in the extent to which they achieved consistency in CBPPR over time and across physicians. All three CCOP organizations demonstrated mixed levels of organizational readiness for change. Hospital management support and resource availability were limited across CCOP organizations early on, although they improved in one CCOP organization. As a result of weak IPPs, all three CCOPs created a weak implementation climate. Patient accrual became concentrated over time among those groups of physicians for whom CBPPR exhibited a strong innovation-values fit. Several external factors influenced innovation use, complicating and enriching our intra-organizational model of innovation implementation. Our results contribute to the limited body of research on the implementation of CBPPR. They inform policy discussions about increasing and sustaining community clinician involvement in clinical research and expand on theory about organizational determinants of implementation effectiveness.

Implementing change in primary care practices using electronic medical records: a conceptual framework.

PubMed

Nemeth, Lynne S; Feifer, Chris; Stuart, Gail W; Ornstein, Steven M

2008-01-16

Implementing change in primary care is difficult, and little practical guidance is available to assist small primary care practices. Methods to structure care and develop new roles are often needed to implement an evidence-based practice that improves care. This study explored the process of change used to implement clinical guidelines for primary and secondary prevention of cardiovascular disease in primary care practices that used a common electronic medical record (EMR). Multiple conceptual frameworks informed the design of this study designed to explain the complex phenomena of implementing change in primary care practice. Qualitative methods were used to examine the processes of change that practice members used to implement the guidelines. Purposive sampling in eight primary care practices within the Practice Partner Research Network-Translating Researching into Practice (PPRNet-TRIP II) clinical trial yielded 28 staff members and clinicians who were interviewed regarding how change in practice occurred while implementing clinical guidelines for primary and secondary prevention of cardiovascular disease and strokes. A conceptual framework for implementing clinical guidelines into primary care practice was developed through this research. Seven concepts and their relationships were modelled within this framework: leaders setting a vision with clear goals for staff to embrace; involving the team to enable the goals and vision for the practice to be achieved; enhancing communication systems to reinforce goals for patient care; developing the team to enable the staff to contribute toward practice improvement; taking small steps, encouraging practices' tests of small changes in practice; assimilating the electronic medical record to maximize clinical effectiveness, enhancing practices' use of the electronic tool they have invested in for patient care improvement; and providing feedback within a culture of improvement, leading to an iterative cycle of goal setting by leaders. This conceptual framework provides a mental model which can serve as a guide for practice leaders implementing clinical guidelines in primary care practice using electronic medical records. Using the concepts as implementation and evaluation criteria, program developers and teams can stimulate improvements in their practice settings. Investing in collaborative team development of clinicians and staff may enable the practice environment to be more adaptive to change and improvement.

Standardizing terms for clinical pharmacogenetic test results: consensus terms from the Clinical Pharmacogenetics Implementation Consortium (CPIC)

PubMed Central

Caudle, Kelly E.; Dunnenberger, Henry M.; Freimuth, Robert R.; Peterson, Josh F.; Burlison, Jonathan D.; Whirl-Carrillo, Michelle; Scott, Stuart A.; Rehm, Heidi L.; Williams, Marc S.; Klein, Teri E.; Relling, Mary V.; Hoffman, James M.

2017-01-01

Introduction: Reporting and sharing pharmacogenetic test results across clinical laboratories and electronic health records is a crucial step toward the implementation of clinical pharmacogenetics, but allele function and phenotype terms are not standardized. Our goal was to develop terms that can be broadly applied to characterize pharmacogenetic allele function and inferred phenotypes. Materials and methods: Terms currently used by genetic testing laboratories and in the literature were identified. The Clinical Pharmacogenetics Implementation Consortium (CPIC) used the Delphi method to obtain a consensus and agree on uniform terms among pharmacogenetic experts. Results: Experts with diverse involvement in at least one area of pharmacogenetics (clinicians, researchers, genetic testing laboratorians, pharmacogenetics implementers, and clinical informaticians; n = 58) participated. After completion of five surveys, a consensus (>70%) was reached with 90% of experts agreeing to the final sets of pharmacogenetic terms. Discussion: The proposed standardized pharmacogenetic terms will improve the understanding and interpretation of pharmacogenetic tests and reduce confusion by maintaining consistent nomenclature. These standard terms can also facilitate pharmacogenetic data sharing across diverse electronic health care record systems with clinical decision support. Genet Med 19 2, 215–223. PMID:27441996

Knowledge Translation Tools are Emerging to Move Neck Pain Research into Practice.

PubMed

Macdermid, Joy C; Miller, Jordan; Gross, Anita R

2013-01-01

Development or synthesis of the best clinical research is in itself insufficient to change practice. Knowledge translation (KT) is an emerging field focused on moving knowledge into practice, which is a non-linear, dynamic process that involves knowledge synthesis, transfer, adoption, implementation, and sustained use. Successful implementation requires using KT strategies based on theory, evidence, and best practice, including tools and processes that engage knowledge developers and knowledge users. Tools can provide instrumental help in implementing evidence. A variety of theoretical frameworks underlie KT and provide guidance on how tools should be developed or implemented. A taxonomy that outlines different purposes for engaging in KT and target audiences can also be useful in developing or implementing tools. Theoretical frameworks that underlie KT typically take different perspectives on KT with differential focus on the characteristics of the knowledge, knowledge users, context/environment, or the cognitive and social processes that are involved in change. Knowledge users include consumers, clinicians, and policymakers. A variety of KT tools have supporting evidence, including: clinical practice guidelines, patient decision aids, and evidence summaries or toolkits. Exemplars are provided of two KT tools to implement best practice in management of neck pain-a clinician implementation guide (toolkit) and a patient decision aid. KT frameworks, taxonomies, clinical expertise, and evidence must be integrated to develop clinical tools that implement best evidence in the management of neck pain.

You can lead a horse to water … what Self-Determination Theory can contribute to our understanding of clinical policy implementation.

PubMed

Smith, Geoffrey P; Williams, Theresa M

2017-01-01

There has been increasing reliance on policy directives as instruments for shaping clinical practice in health care, despite it being widely recognized that there is a significant translation gap between clinical policy and its implementation. Self-Determination Theory, a widely researched and empirically validated theory of human needs' fulfilment and motivation, offers a potentially valuable theoretical framework for understanding not only why the current policy environment has not led to the anticipated improvement in the quality and safety of clinical care but, importantly, also provides guidance about how organizations can create an environment that can nurture behavioural change in the workforce. We describe an alternative approach to clinical policy-making underpinned by Self-Determination Theory, which we believe has broad application for the science of clinical implementation theory.

Multisite Investigation of Strategies for the Implementation of CYP2C19 Genotype-Guided Antiplatelet Therapy.

PubMed

Empey, Philip E; Stevenson, James M; Tuteja, Sony; Weitzel, Kristin W; Angiolillo, Dominick J; Beitelshees, Amber L; Coons, James C; Duarte, Julio D; Franchi, Francesco; Jeng, Linda J B; Johnson, Julie A; Kreutz, Rolf P; Limdi, Nita A; Maloney, Kristin A; Owusu Obeng, Aniwaa; Peterson, Josh F; Petry, Natasha; Pratt, Victoria M; Rollini, Fabiana; Scott, Stuart A; Skaar, Todd C; Vesely, Mark R; Stouffer, George A; Wilke, Russell A; Cavallari, Larisa H; Lee, Craig R

2017-12-26

CYP2C19 genotype-guided antiplatelet therapy following percutaneous coronary intervention is increasingly implemented in clinical practice. However, challenges such as selecting a testing platform, communicating test results, building clinical decision support processes, providing patient and provider education, and integrating methods to support the translation of emerging evidence to clinical practice are barriers to broad adoption. In this report, we compare and contrast implementation strategies of 12 early adopters, describing solutions to common problems and initial performance metrics for each program. Key differences between programs included the test result turnaround time and timing of therapy changes, which are both related to the CYP2C19 testing model and platform used. Sites reported the need for new informatics infrastructure, expert clinicians such as pharmacists to interpret results, physician champions, and ongoing education. Consensus lessons learned are presented to provide a path forward for those seeking to implement similar clinical pharmacogenomics programs within their institutions. © 2018, The American Society for Clinical Pharmacology and Therapeutics.

Perspectives of HIV Clinic Staff on the Implementation of a Client Financial Incentives Program Targeting Viral Suppression.

PubMed

Anderson, Susannah; Jenner, Eric; Lass, Katherine; Burgess, Samuel

We present perspectives of health care providers and clinic staff on the implementation of a financial incentive program for clients living with HIV in three Louisiana clinics. Interviews were conducted in May-June 2015 with 27 clinic staff to assess their perspectives on implementation of the Health Models financial incentive program, which was initiated in September 2013. Many providers and staff welcomed the program, but some were concerned about sustainability and the ethics of a program that paid patients to receive care. Most said they eventually found the program to be helpful for patients and clinic operations in general, by facilitating partnerships between providers and patients, improving appointment keeping, providing opportunities for patient education, engaging patients in care, and helping patients form new prevention habits. The findings can improve understanding of staff and leadership perceptions of incentive programs and can inform planning and implementation of these programs in the future. Copyright © 2017 Association of Nurses in AIDS Care. All rights reserved.

The problem of parental nonadherence in clinical behavior analysis: effective treatment is not enough.

PubMed Central

Allen, K D; Warzak, W J

2000-01-01

Applied behavior analysts have developed many effective interventions for common childhood problems and have repeatedly demonstrated that childhood behavior responds to properly managed contingencies. The success of these interventions is dependent upon their basic effectiveness, as demonstrated in the literature, their precise delivery by the clinician to the parent, and adherence to or consistent implementation of the intervention. Unfortunately, arranging the consistent implementation of effective parenting strategies is a significant challenge for behavior analysts who work in homes, schools, and outpatient or primary care clinics. Much has been done to address issues of adherence or implementation in the clinic, but relatively little has been done to increase our understanding of the contingencies that affect parental adherence beyond the supervised clinic environment. An analysis of the contingencies that strengthen or weaken adherence might suggest strategies to improve implementation outside the clinic setting. What follows is an analysis of the variables associated with adherence by parents to recommendations designed to solve common childhood problems. PMID:11051583

Improving diabetic foot care in a nurse-managed safety-net clinic.

PubMed

Peterson, Joann M; Virden, Mary D

2013-05-01

This article is a description of the development and implementation of a Comprehensive Diabetic Foot Care Program and assessment tool in an academically affiliated nurse-managed, multidisciplinary, safety-net clinic. The assessment tool parallels parameters identified in the Task Force Foot Care Interest Group of the American Diabetes Association's report published in 2008, "Comprehensive Foot Examination and Risk Assessment." Review of literature, Silver City Health Center's (SCHC) 2009 Annual Report, retrospective chart review. Since the full implementation of SCHC's Comprehensive Diabetic Foot Care Program, there have been no hospitalizations of clinic patients for foot-related complications. The development of the Comprehensive Diabetic Foot Assessment tool and the implementation of the Comprehensive Diabetic Foot Care Program have resulted in positive outcomes for the patients in a nurse-managed safety-net clinic. This article demonstrates that quality healthcare services can successfully be developed and implemented in a safety-net clinic setting. ©2012 The Author(s) Journal compilation ©2012 American Association of Nurse Practitioners.

Implementing EHRs: An Exploratory Study to Examine Current Practices in Migrating Physician Practice

PubMed Central

Dolezel, Diane; Moczygemba, Jackie

2015-01-01

Implementation of electronic health record (EHR) systems in physician practices is challenging and complex. In the past, physicians had little incentive to move from paper-based records. With the passage of the Health Information Technology for Economic and Clinical Health (HITECH) Act in 2009, Medicare and Medicaid incentive payments are now available for physicians who implement EHRs for meaningful use. The Office of the National Coordinator for Health Information Technology (ONC) has ample detail on clinical data needed for meaningful use in order to assess the quality of patient care. Details are lacking, however, on how much clinical data, if any, should be transferred from the old paper records during an EHR implementation project. The purpose of this exploratory study was to investigate and document the elements of longitudinal clinical data that are essential for inclusion in the EHR of physicians in a clinical practice setting, as reported by the office managers of the physicians in the study group. PMID:26807077

A stepped-wedge evaluation of an initiative to spread the collaborative care model for depression in primary care.

PubMed

Solberg, Leif I; Crain, A Lauren; Maciosek, Michael V; Unützer, Jürgen; Ohnsorg, Kris A; Beck, Arne; Rubenstein, Lisa; Whitebird, Robin R; Rossom, Rebecca C; Pietruszewski, Pamela B; Crabtree, Benjamin F; Joslyn, Kenneth; Van de Ven, Andrew; Glasgow, Russell E

2015-09-01

Scale-up and spread of evidence-based practices is one of the most important challenges facing health care. We tested whether a statewide initiative, Depression Improvement Across Minnesota-Offering a New Direction (DIAMOND), to implement the collaborative care model for depression in 75 primary care clinics resulted in patient outcome improvements corresponding to those reported in randomized controlled trials. Health plans provided a new monthly payment to participating clinics after a 6-month intensive training program with ongoing data submission, networking, and consultation. Implementation was staggered, with 5 sequences of 10 to 40 clinics every 6 months. Payers provided weekly contact information for members from participating clinics who were filling antidepressant prescriptions, and we conducted baseline and 6-month surveys of 1,578 patients about their care and outcomes. There were 466 patients in DIAMOND clinics who received usual care before implementation (UCB), 559 who received usual care in DIAMOND clinics after implementation (UCA), 245 who received DIAMOND care after implementation (DCA), and 308 who received usual care in comparison clinics (UC). Patients who received DIAMOND care after implementation reported more collaborative care depression services than the 3 comparison groups (10.9 vs 6.4-6.7, on a scale of 0 of 14, where higher numbers indicate more services; P <.001) and more satisfaction with their care (4.0 vs 3.4 on a scale 1 to 5, in which higher scores indicate higher satisfaction; P ≤.001). Depression remission rates, however, were not significantly different among the 4 groups (36.4% DCA vs 35.8% UCB, 35.0% UCA, 33.9% UC; P = .94). Despite the incentive of a supporting payment change and intensive training and support for clinics volunteering to participate, no difference in depression outcomes was documented. Specific unmeasured actions present in trials but not present in these clinics may be critical for successful outcome improvement. © 2015 Annals of Family Medicine, Inc.

The impact of clinical nurse specialists on clinical pathways in the application of evidence-based practice.

PubMed

Gurzick, Martha; Kesten, Karen S

2010-01-01

The purpose of this article was to address the call for evidence-based practice through the development of clinical pathways and to assert the role of the clinical nurse specialist (CNS) as a champion in clinical pathway implementation. In the current health care system, providing quality of care while maintaining cost-effectiveness is an ever-growing battle that institutions face. The CNS's role is central to meeting these demands. An extensive literature review has been conducted to validate the use of clinical pathways as a means of improving patient outcomes. This literature also suggests that clinical pathways must be developed, implemented, and evaluated utilizing validated methods including the use of best practice standards. Execution of clinical pathways should include a clinical expert, who has the ability to look at the system as a whole and can facilitate learning and change by employing a multitude of competencies while maintaining a sphere of influence over patient and families, nurses, and the system. The CNS plays a pivotal role in influencing effective clinical pathway development, implementation, utilization, and ongoing evaluation to ensure improved patient outcomes and reduced costs. This article expands upon the call for evidence-based practice through the utilization of clinical pathways to improve patient outcomes and reduce costs and stresses the importance of the CNS as a primary figure for ensuring proper pathway development, implementation, and ongoing evaluation. Copyright 2010 Elsevier Inc. All rights reserved.

A harmonized and efficient clinical research environment would benefit patients and enhance European competitiveness. Commentary.

PubMed

Amato, Antonino; Aringhieri, Eugenio; Boccia, Stefania; Buccella, Filippo; Gorini, Barbara; Gramaglia, Donatella; Masetti, Riccardo; Rossi, Paolo; Pelicci, Pier Giuseppe

2017-01-01

The forthcoming implementation of the European Clinical Trial Regulation (Regulation (EU) No. 536/2014), which is expected to facilitate the conduct of clinical trials across the European Union, will require National Authorities to create the best conditions for the implementation of the new Regulation through national guidelines, so that sponsors may reconsider Europe as a prime location for planning clinical trials. During a meeting titled "Innovation in Clinical Research", an expert panel discussed potential local advances fostering competitiveness of European clinical research with representatives of the pharmaceutical industry, patient organisations and Italian regulatory agency in view of the forthcoming implementation of (EU) No. 536/2014 on clinical trials of medicinal products. In this article we summarise the findings of the meeting, describe features characterising clinical research patterns and offer some suggestions on the possible involvement of all stakeholders in order to foster research innovation and allow the timely access to novel medicines for patients.

Review of the Reported Measures of Clinical Validity and Clinical Utility as Arguments for the Implementation of Pharmacogenetic Testing: A Case Study of Statin-Induced Muscle Toxicity.

PubMed

Jansen, Marleen E; Rigter, T; Rodenburg, W; Fleur, T M C; Houwink, E J F; Weda, M; Cornel, Martina C

2017-01-01

Advances from pharmacogenetics (PGx) have not been implemented into health care to the expected extent. One gap that will be addressed in this study is a lack of reporting on clinical validity and clinical utility of PGx-tests. A systematic review of current reporting in scientific literature was conducted on publications addressing PGx in the context of statins and muscle toxicity. Eighty-nine publications were included and information was selected on reported measures of effect, arguments, and accompanying conclusions. Most authors report associations to quantify the relationship between a genetic variation an outcome, such as adverse drug responses. Conclusions on the implementation of a PGx-test are generally based on these associations, without explicit mention of other measures relevant to evaluate the test's clinical validity and clinical utility. To gain insight in the clinical impact and select useful tests, additional outcomes are needed to estimate the clinical validity and utility, such as cost-effectiveness.

Implementation of clinical governance in hospitals: challenges and the keys for success.

PubMed

Mousavi, Seyed Mohammad Hadi; Agharahimi, Zahra; Daryabeigi, Maede; Rezaei, Nima

2014-01-01

There is a number of models and strategies for improving the quality of care such as total quality management, continuous quality improvement and clinical governance. The policy of clinical governance is part of the governments overall strategy for monitoring, assuring and improving in the national health services organization. Clinical governance has been introduced as a bridge between managerial and clinical approaches to quality. For successful implementing of clinical governance, it is necessary to pay attention to firm foundations of the structure, including equipment, staffing arrangement, supporting specialties, and staff training. Therefore, as clinical governance improves safety and quality in health care services, the current situation in hospitals should be evaluated before any intervention while barriers and blocks on structure and process should be determined to select a method for changing them. Considering these points could guarantee success in implementation of clinical governance; otherwise there would be a little chance to achieve the desired results despite consumption of plenty of time and huge paper works.

Implementation of the CALM intervention for anxiety disorders: a qualitative study

PubMed Central

2012-01-01

Background Investigators recently tested the effectiveness of a collaborative-care intervention for anxiety disorders: Coordinated Anxiety Learning and Management(CALM) []) in 17 primary care clinics around the United States. Investigators also conducted a qualitative process evaluation. Key research questions were as follows: (1) What were the facilitators/barriers to implementing CALM? (2) What were the facilitators/barriers to sustaining CALM after the study was completed? Methods Key informant interviews were conducted with 47 clinic staff members (18 primary care providers, 13 nurses, 8 clinic administrators, and 8 clinic staff) and 14 study-trained anxiety clinical specialists (ACSs) who coordinated the collaborative care and provided cognitive behavioral therapy. The interviews were semistructured and conducted by phone. Data were content analyzed with line-by-line analyses leading to the development and refinement of themes. Results Similar themes emerged across stakeholders. Important facilitators to implementation included the perception of "low burden" to implement, provider satisfaction with the intervention, and frequent provider interaction with ACSs. Barriers to implementation included variable provider interest in mental health, high rates of part-time providers in clinics, and high social stressors of lower socioeconomic-status patients interfering with adherence. Key sustainability facilitators were if a clinic had already incorporated collaborative care for another disorder and presence of onsite mental health staff. The main barrier to sustainability was funding for the ACS. Conclusions The CALM intervention was relatively easy to incorporate during the effectiveness trial, and satisfaction was generally high. Numerous implementation and sustainability barriers could limit the reach and impact of widespread adoption. Findings should be interpreted with the knowledge that the ACSs in this study were provided and trained by the study. Future research should explore uptake of CALM and similar interventions without the aid of an effectiveness trial. PMID:22404963

Stakeholder Engagement in a Patient-Reported Outcomes (PRO) Measure Implementation: A Report from the SAFTINet Practice-based Research Network (PBRN).

PubMed

Kwan, Bethany M; Sills, Marion R; Graham, Deborah; Hamer, Mika K; Fairclough, Diane L; Hammermeister, K E; Kaiser, Alicyn; de Jesus Diaz-Perez, Maria; Schilling, Lisa M

2016-01-01

Patient-reported outcome (PRO) measures offer value for clinicians and researchers, although priorities and value propositions can conflict. PRO implementation in clinical practice may benefit from stakeholder engagement methods to align research and clinical practice stakeholder perspectives. The objective is to demonstrate the use of stakeholder engagement in PRO implementation. Engaged stakeholders represented researchers and clinical practice representatives from the SAFTINet practice-based research network (PBRN). A stakeholder engagement process involving iterative analysis, deliberation, and decision making guided implementation of a medication adherence PRO measure (the Medication Adherence Survey [MAS]) for patients with hypertension and/or hyperlipidemia. Over 9 months, 40 of 45 practices (89%) implemented the MAS, collecting 3,247 surveys (mean = 72, median = 30, range: 0 - 416). Facilitators included: an electronic health record (EHR) with readily modifiable templates; existing staff, tools and workflows in which the MAS could be integrated (e.g., health risk appraisals, hypertension-specific visits, care coordinators); and engaged leadership and quality improvement teams. Stakeholder engagement appeared useful for promoting PRO measure implementation in clinical practice, in a way that met the needs of both researchers and clinical practice stakeholders. Limitations of this approach and opportunities for improving the PRO data collection infrastructure in PBRNs are discussed. © Copyright 2016 by the American Board of Family Medicine.

A Little Effort Can Withstand the Hardship: Fielding an Internet-Based Intervention to Prevent Depression among Urban Racial/Ethnic Minority Adolescents in a Primary Care Setting.

PubMed

Bansa, Melishia; Brown, Darryl; DeFrino, Daniela; Mahoney, Nicholas; Saulsberry, Alexandria; Marko-Holguin, Monika; Fogel, Joshua; Gladstone, Tracy R G; Van Voorhees, Benjamin W

2018-04-01

This study explored the implementation of Chicago Urban Resiliency Building (CURB), a randomized clinical trial designed as an Internet-based primary care depression prevention intervention for urban African American and Latino adolescents. We utilized a mixed methods analysis to explore four aims. First, we estimated the percent of at-risk adolescents that were successfully screened. Second, we examined clinic site factors and performance. Third, primary care providers (n = 10) and clinic staff (n = 18) were surveyed to assess their knowledge and attitudes about the intervention. Fourth, clinic staff (nursing and medical assistant) interviews were analyzed using thematic analysis to gather perspectives of the implementation process. We found that the estimated percent of at-risk adolescents who were successfully screened in each clinic varied widely between clinics with a mean of 14.48%. Daily clinic communication was suggestive of greater successful screening. Feasibility of screening was high for both primary care providers and clinic staff. Clinic staff exit interviews indicated the presence of community barriers that inhibited successful implementation of the intervention. This study shares the challenges and successes for depression screening and implementing Internet-based mental health interventions for urban racial/ethnic minority adolescents in primary care settings. Published by Elsevier Inc.

Clinical Problem Solving Exercises for Pre-Clinical Medical Education: A Design, Implementation and Preliminary Evaluation.

ERIC Educational Resources Information Center

Bordage, Georges

Clinical problem solving exercises for preclinical medical education that were developed at Michigan State University School of Osteopathic Medicine are described. Two types of outcomes were set as priorities in the design and implementation of the problem solving sessions: small group peer interactions as instructional and evaluative resources;…

An innovative clinical practicum to teach evidence-based practice.

PubMed

Brancato, Vera C

2006-01-01

A clinical practicum was successfully implemented for RN to BSN students to apply evidence-based practice to actual clinical problems affecting nursing practice. The author describes how this practicum was implemented and the requisite resources and support systems. This senior-level capstone course enabled students to understand and value a lifelong learning approach to evidence-based practice.

Dissemination Strategies to Improve Implementation of the PHS Smoking Cessation Guideline in MCH Public Health Clinics: Experimental Evaluation Results and Contextual Factors

ERIC Educational Resources Information Center

Manfredi, Clara; Cho, Young Ik; Warnecke, Richard; Saunders, Stephen; Sullivan, Myrtis

2011-01-01

We report results from an experimental study that tested the effectiveness of dissemination interventions to improve implementation of smoking cessation guidelines in maternal and child public health clinics. We additionally examine individual clinic results for contextual explanations not apparent from the experimental findings alone. Twelve…

Automating Guidelines for Clinical Decision Support: Knowledge Engineering and Implementation.

PubMed

Tso, Geoffrey J; Tu, Samson W; Oshiro, Connie; Martins, Susana; Ashcraft, Michael; Yuen, Kaeli W; Wang, Dan; Robinson, Amy; Heidenreich, Paul A; Goldstein, Mary K

2016-01-01

As utilization of clinical decision support (CDS) increases, it is important to continue the development and refinement of methods to accurately translate the intention of clinical practice guidelines (CPG) into a computable form. In this study, we validate and extend the 13 steps that Shiffman et al. 5 identified for translating CPG knowledge for use in CDS. During an implementation project of ATHENA-CDS, we encoded complex CPG recommendations for five common chronic conditions for integration into an existing clinical dashboard. Major decisions made during the implementation process were recorded and categorized according to the 13 steps. During the implementation period, we categorized 119 decisions and identified 8 new categories required to complete the project. We provide details on an updated model that outlines all of the steps used to translate CPG knowledge into a CDS integrated with existing health information technology.

Implementing clinical governance in English primary care groups/trusts: reconciling quality improvement and quality assurance.

PubMed

Campbell, S M; Sheaff, R; Sibbald, B; Marshall, M N; Pickard, S; Gask, L; Halliwell, S; Rogers, A; Roland, M O

2002-03-01

To investigate the concept of clinical governance being advocated by primary care groups/trusts (PCG/Ts), approaches being used to implement clinical governance, and potential barriers to its successful implementation in primary care. Qualitative case studies using semi-structured interviews and documentation review. Twelve purposively sampled PCG/Ts in England. Fifty senior staff including chief executives, clinical governance leads, mental health leads, and lay board members. Participants' perceptions of the role of clinical governance in PCG/Ts. PCG/Ts recognise that the successful implementation of clinical governance in general practice will require cultural as well as organisational changes, and the support of practices. They are focusing their energies on supporting practices and getting them involved in quality improvement activities. These activities include, but move beyond, conventional approaches to quality assessment (audit, incentives) to incorporate approaches which emphasise corporate and shared learning. PCG/Ts are also engaged in setting up systems for monitoring quality and for dealing with poor performance. Barriers include structural barriers (weak contractual levers to influence general practices), resource barriers (perceived lack of staff or money), and cultural barriers (suspicion by practice staff or problems overcoming the perceived blame culture associated with quality assessment). PCG/Ts are focusing on setting up systems for implementing clinical governance which seek to emphasise developmental and supportive approaches which will engage health professionals. Progress is intentionally incremental but formidable challenges lie ahead, not least reconciling the dual role of supporting practices while monitoring (and dealing with poor) performance.

Validating and determining the weight of items used for evaluating clinical governance implementation based on analytic hierarchy process model.

PubMed

Hooshmand, Elaheh; Tourani, Sogand; Ravaghi, Hamid; Vafaee Najar, Ali; Meraji, Marziye; Ebrahimipour, Hossein

2015-04-08

The purpose of implementing a system such as Clinical Governance (CG) is to integrate, establish and globalize distinct policies in order to improve quality through increasing professional knowledge and the accountability of healthcare professional toward providing clinical excellence. Since CG is related to change, and change requires money and time, CG implementation has to be focused on priority areas that are in more dire need of change. The purpose of the present study was to validate and determine the significance of items used for evaluating CG implementation. The present study was descriptive-quantitative in method and design. Items used for evaluating CG implementation were first validated by the Delphi method and then compared with one another and ranked based on the Analytical Hierarchy Process (AHP) model. The items that were validated for evaluating CG implementation in Iran include performance evaluation, training and development, personnel motivation, clinical audit, clinical effectiveness, risk management, resource allocation, policies and strategies, external audit, information system management, research and development, CG structure, implementation prerequisites, the management of patients' non-medical needs, complaints and patients' participation in the treatment process. The most important items based on their degree of significance were training and development, performance evaluation, and risk management. The least important items included the management of patients' non-medical needs, patients' participation in the treatment process and research and development. The fundamental requirements of CG implementation included having an effective policy at national level, avoiding perfectionism, using the expertise and potentials of the entire country and the coordination of this model with other models of quality improvement such as accreditation and patient safety. © 2015 by Kerman University of Medical Sciences.

Improved outcomes after successful implementation of a pediatric early warning system (PEWS) in a resource-limited pediatric oncology hospital.

PubMed

Agulnik, Asya; Mora Robles, Lupe Nataly; Forbes, Peter W; Soberanis Vasquez, Doris Judith; Mack, Ricardo; Antillon-Klussmann, Federico; Kleinman, Monica; Rodriguez-Galindo, Carlos

2017-08-01

Hospitalized pediatric oncology patients are at high risk of clinical decline and mortality, particularly in resource-limited settings. Pediatric early warning systems (PEWS) aid in the early identification of clinical deterioration; however, there are limited data regarding their feasibility or impact in low-resource settings. This study describes the successful implementation of PEWS at the Unidad Nacional de Oncología Pediátrica (UNOP), a pediatric oncology hospital in Guatemala, resulting in improved inpatient outcomes. A modified PEWS was implemented at UNOP with systems to track errors, transfers to a higher level of care, and high scores. A retrospective cohort study was used to evaluate clinical deterioration events in the year before and after PEWS implementation. After PEWS implementation at UNOP, there was 100% compliance with PEWS documentation and an error rate of <10%. Implementation resulted in 5 high PEWS per week, with 30% of patients transferring to a higher level of care. Among patients requiring transfer to the pediatric intensive care unit (PICU), 93% had an abnormal PEWS before transfer. The rate of clinical deterioration events decreased after PEWS implementation (9.3 vs 6.5 per 1000-hospitalpatient-days, p = .003). Despite an 18% increase in total hospital patient-days, PICU utilization for inpatient transfers decreased from 1376 to 1088 PICU patient-days per year (21% decrease; P<.001). This study describes the successful implementation of PEWS in a pediatric oncology hospital in Guatemala, resulting in decreased inpatient clinical deterioration events and PICU utilization. This work demonstrates that PEWS is a feasible and effective quality improvement measure to improve hospital care for children with cancer in hospitals with limited resources. Cancer 2017;123:2965-74. © 2017 American Cancer Society. © 2017 American Cancer Society.

Implementing pharmacogenomics decision support across seven European countries: The Ubiquitous Pharmacogenomics (U-PGx) project.

PubMed

Blagec, Kathrin; Koopmann, Rudolf; Crommentuijn-van Rhenen, Mandy; Holsappel, Inge; van der Wouden, Cathelijne H; Konta, Lidija; Xu, Hong; Steinberger, Daniela; Just, Enrico; Swen, Jesse J; Guchelaar, Henk-Jan; Samwald, Matthias

2018-02-09

Clinical pharmacogenomics (PGx) has the potential to make pharmacotherapy safer and more effective by utilizing genetic patient data for drug dosing and selection. However, widespread adoption of PGx depends on its successful integration into routine clinical care through clinical decision support tools, which is often hampered by insufficient or fragmented infrastructures. This paper describes the setup and implementation of a unique multimodal, multilingual clinical decision support intervention consisting of digital, paper-, and mobile-based tools that are deployed across implementation sites in seven European countries participating in the Ubiquitous PGx (U-PGx) project. © The Author(s) 2018. Published by Oxford University Press on behalf of the American Medical Informatics Association.

Pragmatic trial of a multidisciplinary lung cancer care model in a community healthcare setting: study design, implementation evaluation, and baseline clinical results

PubMed Central

Smeltzer, Matthew P.; Rugless, Fedoria E.; Jackson, Bianca M.; Berryman, Courtney L.; Faris, Nicholas R.; Ray, Meredith A.; Meadows, Meghan; Patel, Anita A.; Roark, Kristina S.; Kedia, Satish K.; DeBon, Margaret M.; Crossley, Fayre J.; Oliver, Georgia; McHugh, Laura M.; Hastings, Willeen; Osborne, Orion; Osborne, Jackie; Ill, Toni; Ill, Mark; Jones, Wynett; Lee, Hyo K.; Signore, Raymond S.; Fox, Roy C.; Li, Jingshan; Robbins, Edward T.; Ward, Kenneth D.; Klesges, Lisa M.

2018-01-01

Background Responsible for 25% of all US cancer deaths, lung cancer presents complex care-delivery challenges. Adoption of the highly recommended multidisciplinary care model suffers from a dearth of good quality evidence. Leading up to a prospective comparative-effectiveness study of multidisciplinary vs. serial care, we studied the implementation of a rigorously benchmarked multidisciplinary lung cancer clinic. Methods We used a mixed-methods approach to conduct a patient-centered, combined implementation and effectiveness study of a multidisciplinary model of lung cancer care. We established a co-located multidisciplinary clinic to study the implementation of this care-delivery model. We identified and engaged key stakeholders from the onset, used their input to develop the program structure, processes, performance benchmarks, and study endpoints (outcome-related process measures, patient- and caregiver-reported outcomes, survival). In this report, we describe the study design, process of implementation, comparative populations, and how they contrast with patients within the local and regional healthcare system. Trial Registration: ClinicalTrials.gov Identifier: NCT02123797. Results Implementation: the multidisciplinary clinic obtained an overall treatment concordance rate of 90% (target >85%). Satisfaction scores were high, with >95% of patients and caregivers rating themselves as being “very satisfied” with all aspects of care from the multidisciplinary team (patient/caregiver response rate >90%). The Reach of the multidisciplinary clinic included a higher proportion of minority patients, more women, and younger patients than the regional population. Comparative effectiveness: The comparative effectiveness trial conducted in the last phase of the study met the planned enrollment per statistical design, with 178 patients in the multidisciplinary arm and 348 in the serial care arm. The multidisciplinary cohort had older age and a higher percentage of racial minorities, with a higher proportion of stage IV patients in the serial care arm. Conclusions This study demonstrates a comprehensive implementation of a multidisciplinary model of lung cancer care, which will advance the science behind implementing this much-advocated clinical care model. PMID:29535915

Drug safety assurance through clinical genotyping: near-term considerations for a system-wide implementation of personalized medicine.

PubMed

Kane, Michael D; Springer, John A; Sprague, Jon E

2008-07-01

The rationale and overall system-wide behavior of a clinical genotyping information system (both DNA analysis and data management) requires a near-term, scalable approach, which is emerging in the focused implementation of pharmacogenomics and drug safety assurance. The challenges to implementing a successful clinical genotyping system are described, as are how the benefits of a focused, near-term system for drug safety assessment and assurance overcome the logistical and operational challenges that perpetually hinder the development of a societal-scale clinical genotyping system. This rationale is based on the premise that a focused application domain for clinical genotyping, specifically drug safety assurance, provides a transition paradigm for both professionals and consumers of healthcare, thereby facilitating the movement of genotyping from bench to bedside and paving the way for the adoption of prognostic and diagnostic applications in clinical genomics.

What would it take? Stakeholders' views and preferences for implementing a health care manager program in community mental health clinics under health care reform.

PubMed

Cabassa, Leopoldo J; Gomes, Arminda P; Lewis-Fernández, Roberto

2015-02-01

Health care manager interventions can improve the physical health of people with serious mental illness (SMI). In this study, we used concepts from the theory of diffusion of innovations, the consolidated framework for implementation research and a taxonomy of implementation strategies to examine stakeholders' recommendations for implementing a health care manager intervention in public mental health clinics serving Hispanics with SMI. A purposive sample of 20 stakeholders was recruited from mental health agencies, primary care clinics, and consumer advocacy organizations. We presented participants a vignette describing a health care manager intervention and used semistructured qualitative interviews to examine their views and recommendations for implementing this program. Interviews were recorded, professionally transcribed, and content analyzed. We found that a blend of implementation strategies that demonstrates local relative advantage, addresses cost concerns, and enhances compatibility to organizations and the client population is critical for moving health care manager interventions into practice. © The Author(s) 2014.

What Would It Take? Stakeholders’ Views and Preferences for Implementing a Health Care Manager Program in Community Mental Health Clinics Under Health Care Reform

PubMed Central

Cabassa, Leopoldo J.; Gomes, Arminda P.; Lewis-Fernández, Roberto

2015-01-01

Health care manager interventions can improve the physical health of people with serious mental illness (SMI). In this study, we used concepts from the theory of diffusion of innovations, the consolidated framework for implementation research and a taxonomy of implementation strategies to examine stakeholders’ recommendations for implementing a health care manager intervention in public mental health clinics serving Hispanics with SMI. A purposive sample of 20 stakeholders was recruited from mental health agencies, primary care clinics, and consumer advocacy organizations. We presented participants a vignette describing a health care manager intervention and used semistructured qualitative interviews to examine their views and recommendations for implementing this program. Interviews were recorded, professionally transcribed, and content analyzed. We found that a blend of implementation strategies that demonstrates local relative advantage, addresses cost concerns, and enhances compatibility to organizations and the client population is critical for moving health care manager interventions into practice. PMID:25542194

Implementation of pharmacogenetics: the University of Maryland Personalized Anti-platelet Pharmacogenetics Program.

PubMed

Shuldiner, Alan R; Palmer, Kathleen; Pakyz, Ruth E; Alestock, Tameka D; Maloney, Kristin A; O'Neill, Courtney; Bhatty, Shaun; Schub, Jamie; Overby, Casey Lynnette; Horenstein, Richard B; Pollin, Toni I; Kelemen, Mark D; Beitelshees, Amber L; Robinson, Shawn W; Blitzer, Miriam G; McArdle, Patrick F; Brown, Lawrence; Jeng, Linda Jo Bone; Zhao, Richard Y; Ambulos, Nicholas; Vesely, Mark R

2014-03-01

Despite a substantial evidence base, implementation of pharmacogenetics into routine patient care has been slow due to a number of non-trivial practical barriers. We implemented a Personalized Anti-platelet Pharmacogenetics Program (PAP3) for cardiac catheterization patients at the University of Maryland Medical Center and the Baltimore Veterans Administration Medical Center Patients' are offered CYP2C19 genetic testing, which is performed in our Clinical Laboratory Improvement Amendment (CLIA)-certified Translational Genomics Laboratory. Results are returned within 5 hr along with clinical decision support that includes interpretation of results and prescribing recommendations for anti-platelet therapy based on the Clinical Pharmacogenetics Implementation Consortium guidelines. Now with a working template for PAP3, implementation of other drug-gene pairs is in process. Lessons learned as described in this article may prove useful to other medical centers as they implement pharmacogenetics into patient care, a critical step in the pathway to personalized and genomic medicine. © 2014 Wiley Periodicals, Inc.

IMPLEMENTATION OF PHARMACOGENETICS: THE UNIVERSITY OF MARYLAND PERSONALIZED ANTI-PLATELET PHARMACOGENETICS PROGRAM

PubMed Central

Shuldiner, Alan R.; Palmer, Kathleen; Pakyz, Ruth E.; Alestock, Tameka D.; Maloney, Kristin A.; O’Neill, Courtney; Bhatty, Shaun; Schub, Jamie; Overby, Casey Lynnette; Horenstein, Richard B.; Pollin, Toni I.; Kelemen, Mark D.; Beitelshees, Amber L.; Robinson, Shawn W.; Blitzer, Miriam G.; McArdle, Patrick F.; Brown, Lawrence; Jeng, Linda Jo Bone; Zhao, Richard Y.; Ambulos, Nicholas; Vesely, Mark R.

2014-01-01

Despite a substantial evidence base, implementation of pharmacogenetics into routine patient care has been slow due to a number of non-trivial practical barriers. We implemented a Personalized Anti-platelet Pharmacogenetics Program (PAP3) for cardiac catheterization patients at the University of Maryland Medical Center and the Baltimore Veterans Administration Medical Center Patients are offered CYP2C19 genetic testing, which is performed in our Clinical Laboratory Improvement Amendment (CLIA)-certified Translational Genomics Laboratory. Results are returned within five hours along with clinical decision support that includes interpretation of results and prescribing recommendations for anti-platelet therapy based on the Clinical Pharmacogenetics Implementation Consortium guidelines. Now with a working template for PAP3, implementation of other drug-gene pairs is in process. Lessons learned as described in this article may prove useful to other medical centers as they implement pharmacogenetics into patient care, a critical step in the pathway to personalized and genomic medicine. PMID:24616408

Recommended Implementation of Arterial Spin Labeled Perfusion MRI for Clinical Applications: A consensus of the ISMRM Perfusion Study Group and the European Consortium for ASL in Dementia

PubMed Central

Alsop, David C.; Detre, John A.; Golay, Xavier; Günther, Matthias; Hendrikse, Jeroen; Hernandez-Garcia, Luis; Lu, Hanzhang; MacIntosh, Bradley J.; Parkes, Laura M.; Smits, Marion; van Osch, Matthias J. P.; Wang, Danny JJ; Wong, Eric C.; Zaharchuk, Greg

2014-01-01

This article provides a summary statement of recommended implementations of arterial spin labeling (ASL) for clinical applications. It is a consensus of the ISMRM Perfusion Study Group and the European ‘ASL in Dementia’ consortium, both of whom met to reach this consensus in October 2012 in Amsterdam. Although ASL continues to undergo rapid technical development, we believe that current ASL methods are robust and ready to provide useful clinical information, and that a consensus statement on recommended implementations will help the clinical community to adopt a standardized approach. In this article we describe the major considerations and tradeoffs in implementing an ASL protocol, and provide specific recommendations for a standard approach. Our conclusions are that, as an optimal default implementation we recommend: pseudo-continuous labeling, background suppression, a segmented 3D readout without vascular crushing gradients, and calculation and presentation of both label/control difference images and cerebral blood flow in absolute units using a simplified model. PMID:24715426

Clinical ladder program implementation: a project guide.

PubMed

Ko, Yu Kyung; Yu, Soyoung

2014-11-01

This article describes the development of a clinical ladder program (CLP) implementation linked to a promotion system for nurses. The CLP task force developed criteria for each level of performance and a performance evaluation tool reflecting the self-motivation of the applicant for professional development. One year after implementation, the number of nurses taking graduate courses increased, and 7 nurses were promoted to nurse manager positions.

Speech pathologists' experiences with stroke clinical practice guidelines and the barriers and facilitators influencing their use: a national descriptive study.

PubMed

Hadely, Kathleen A; Power, Emma; O'Halloran, Robyn

2014-03-06

Communication and swallowing disorders are a common consequence of stroke. Clinical practice guidelines (CPGs) have been created to assist health professionals to put research evidence into clinical practice and can improve stroke care outcomes. However, CPGs are often not successfully implemented in clinical practice and research is needed to explore the factors that influence speech pathologists' implementation of stroke CPGs. This study aimed to describe speech pathologists' experiences and current use of guidelines, and to identify what factors influence speech pathologists' implementation of stroke CPGs. Speech pathologists working in stroke rehabilitation who had used a stroke CPG were invited to complete a 39-item online survey. Content analysis and descriptive and inferential statistics were used to analyse the data. 320 participants from all states and territories of Australia were surveyed. Almost all speech pathologists had used a stroke CPG and had found the guideline "somewhat useful" or "very useful". Factors that speech pathologists perceived influenced CPG implementation included the: (a) guideline itself, (b) work environment, (c) aspects related to the speech pathologist themselves, (d) patient characteristics, and (e) types of implementation strategies provided. There are many different factors that can influence speech pathologists' implementation of CPGs. The factors that influenced the implementation of CPGs can be understood in terms of knowledge creation and implementation frameworks. Speech pathologists should continue to adapt the stroke CPG to their local work environment and evaluate their use. To enhance guideline implementation, they may benefit from a combination of educational meetings and resources, outreach visits, support from senior colleagues, and audit and feedback strategies.

Pharmacogenetics in Cardiovascular Medicine

PubMed Central

Tuteja, Sony; Limdi, Nita

2017-01-01

Purpose of review Pharmacogenetics is an important component of precision medicine. Even within the genomic era, several challenges lie ahead in the road towards clinical implementation of pharmacogenetics in the clinic. This review will summarize the current state of knowledge regarding pharmacogenetics of cardiovascular drugs, focusing on those with the most evidence supporting clinical implementation- clopidogrel, warfarin and simvastatin. Recent findings There is limited translation of pharmacogenetics into clinical practice primarily due to the absence of outcomes data from prospective, randomized, genotype-directed clinical trials. There are several ongoing randomized controlled trials that will provide some answers as to the clinical utility of genotype-directed strategies. Several academic medical centers have pushed towards clinical implementation where the clinical validity data are strong. Their experiences will inform operational requirements of a clinical pharmacogenetics testing including the timing of testing, incorporation of test results into the electronic health record, reimbursement and ethical issues. Summary Pharmacogenetics of clopidogrel, warfarin and simvastatin are three examples where pharmacogenetics testing may provide added clinical value. Continued accumulation of evidence surrounding clinical utility of pharmacogenetics markers is imperative as this will inform reimbursement policy and drive adoption of pharamcogenetics into routine care. PMID:29057167

Moving research tools into practice: the successes and challenges in promoting uptake of classification tools.

PubMed

Cunningham, Barbara Jane; Hidecker, Mary Jo Cooley; Thomas-Stonell, Nancy; Rosenbaum, Peter

2018-05-01

In this paper, we present our experiences - both successes and challenges - in implementing evidence-based classification tools into clinical practice. We also make recommendations for others wanting to promote the uptake and application of new research-based assessment tools. We first describe classification systems and the benefits of using them in both research and practice. We then present a theoretical framework from Implementation Science to report strategies we have used to implement two research-based classification tools into practice. We also illustrate some of the challenges we have encountered by reporting results from an online survey investigating 58 Speech-language Pathologists' knowledge and use of the Communication Function Classification System (CFCS), a new tool to classify children's functional communication skills. We offer recommendations for researchers wanting to promote the uptake of new tools in clinical practice. Specifically, we identify structural, organizational, innovation, practitioner, and patient-related factors that we recommend researchers address in the design of implementation interventions. Roles and responsibilities of both researchers and clinicians in making implementations science a success are presented. Implications for rehabilitation Promoting uptake of new and evidence-based tools into clinical practice is challenging. Implementation science can help researchers to close the knowledge-to-practice gap. Using concrete examples, we discuss our experiences in implementing evidence-based classification tools into practice within a theoretical framework. Recommendations are provided for researchers wanting to implement new tools in clinical practice. Implications for researchers and clinicians are presented.

Can the theoretical domains framework account for the implementation of clinical quality interventions?

PubMed

Lipworth, Wendy; Taylor, Natalie; Braithwaite, Jeffrey

2013-12-21

The health care quality improvement movement is a complex enterprise. Implementing clinical quality initiatives requires attitude and behaviour change on the part of clinicians, but this has proven to be difficult. In an attempt to solve this kind of behavioural challenge, the theoretical domains framework (TDF) has been developed. The TDF consists of 14 domains from psychological and organisational theory said to influence behaviour change. No systematic research has been conducted into the ways in which clinical quality initiatives map on to the domains of the framework. We therefore conducted a qualitative mapping experiment to determine to what extent, and in what ways, the TDF is relevant to the implementation of clinical quality interventions. We conducted a thematic synthesis of the qualitative literature exploring clinicians' perceptions of various clinical quality interventions. We analysed and synthesised 50 studies in total, in five domains of clinical quality interventions: clinical quality interventions in general, structural interventions, audit-type interventions, interventions aimed at making practice more evidence-based, and risk management interventions. Data were analysed thematically, followed by synthesis of these themes into categories and concepts, which were then mapped to the domains of the TDF. Our results suggest that the TDF is highly relevant to the implementation of clinical quality interventions. It can be used to map most, if not all, of the attitudinal and behavioural barriers and facilitators of uptake of clinical quality interventions. Each of these 14 domains appeared to be relevant to many different types of clinical quality interventions. One possible additional domain might relate to perceived trustworthiness of those instituting clinical quality interventions. The TDF can be usefully applied to a wide range of clinical quality interventions. Because all 14 of the domains emerged as relevant, and we did not identify any obvious differences between different kinds of clinical quality interventions, our findings support an initially broad approach to identifying barriers and facilitators, followed by a "drilling down" to what is most contextually salient. In future, it may be possible to establish a model of clinical quality policy implementation using the TDF.

Can the theoretical domains framework account for the implementation of clinical quality interventions?

PubMed Central

2013-01-01

Background The health care quality improvement movement is a complex enterprise. Implementing clinical quality initiatives requires attitude and behaviour change on the part of clinicians, but this has proven to be difficult. In an attempt to solve this kind of behavioural challenge, the theoretical domains framework (TDF) has been developed. The TDF consists of 14 domains from psychological and organisational theory said to influence behaviour change. No systematic research has been conducted into the ways in which clinical quality initiatives map on to the domains of the framework. We therefore conducted a qualitative mapping experiment to determine to what extent, and in what ways, the TDF is relevant to the implementation of clinical quality interventions. Methods We conducted a thematic synthesis of the qualitative literature exploring clinicians’ perceptions of various clinical quality interventions. We analysed and synthesised 50 studies in total, in five domains of clinical quality interventions: clinical quality interventions in general, structural interventions, audit-type interventions, interventions aimed at making practice more evidence-based, and risk management interventions. Data were analysed thematically, followed by synthesis of these themes into categories and concepts, which were then mapped to the domains of the TDF. Results Our results suggest that the TDF is highly relevant to the implementation of clinical quality interventions. It can be used to map most, if not all, of the attitudinal and behavioural barriers and facilitators of uptake of clinical quality interventions. Each of these 14 domains appeared to be relevant to many different types of clinical quality interventions. One possible additional domain might relate to perceived trustworthiness of those instituting clinical quality interventions. Conclusions The TDF can be usefully applied to a wide range of clinical quality interventions. Because all 14 of the domains emerged as relevant, and we did not identify any obvious differences between different kinds of clinical quality interventions, our findings support an initially broad approach to identifying barriers and facilitators, followed by a “drilling down” to what is most contextually salient. In future, it may be possible to establish a model of clinical quality policy implementation using the TDF. PMID:24359085

Evaluation of the implementation of a clinical pharmacy service on an acute internal medicine ward in Italy.

PubMed

Lombardi, Nicola; Wei, Li; Ghaleb, Maisoon; Pasut, Enrico; Leschiutta, Silvia; Rossi, Paolo; Troncon, Maria Grazia

2018-04-10

Successful implementation of clinical pharmacy services is associated with improvement of appropriateness of prescribing. Both high clinical significance of pharmacist interventions and their high acceptance rate mean that potential harm to patients could be avoided. Evidence shows that low acceptance rate of pharmacist interventions can be associated with lack of communication between pharmacists and the rest of the healthcare team. The objective of this study was to evaluate the effect of a structured communication strategy on acceptance rate of interventions made by a clinical pharmacist implementing a ward-based clinical pharmacy service targeting elderly patients at high risk of drug-related problems. Characteristics of interventions made to improve appropriateness of prescribing, their clinical significance and intervention acceptance rate by doctors were recorded. A clinical pharmacy intervention study was conducted between September 2013 and December 2013 in an internal medicine ward of a teaching hospital. A trained clinical pharmacist provided pharmaceutical care to 94 patients aged over 70 years. The clinical pharmacist used the following communication and marketing tools to implement the service described: Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis; Specific, Measurable, Achievable, Realistic and Timely (SMART) goals; Awareness, Interest, Desire, Action (AIDA) model. A total of 740 interventions were made by the clinical pharmacist. The most common drug classes involved in interventions were: antibacterials for systemic use (11.1%) and anti-parkinson drugs (10.8%). The main drug-related problem categories triggering interventions were: no specific problem (15.9%) and prescription writing error (12.0%). A total of 93.2% of interventions were fully accepted by physicians. After assessment by an external panel 63.2% of interventions (96 interventions/ per month) were considered of moderate clinical significance and 23.4% (36 interventions/ per month) of major clinical significance. The most frequent interventions were to educate a healthcare professional (20.4%) and change dose (16.1%). To our knowledge this is the first study evaluating the effect of a structured communication strategy on acceptance rate of pharmacist interventions. Pharmaceutical care delivered by the clinical pharmacist is likely to have had beneficial outcomes. Clinical pharmacy services like the one described should be implemented widely to increase patient safety.

Considering health equity when moving from evidence-based guideline recommendations to implementation: a case study from an upper-middle income country on the GRADE approach

PubMed Central

Mosquera, Paola; Alzate, Juan Pablo; Pottie, Kevin; Welch, Vivian; Akl, Elie A; Jull, Janet; Lang, Eddy; Katikireddi, Srinivasa Vittal; Morton, Rachel; Thabane, Lehana; Shea, Bev; Stein, Airton T; Singh, Jasvinder; Florez, Ivan D; Guyatt, Gordon; Schünemann, Holger; Tugwell, Peter

2017-01-01

Abstract The availability of evidence-based guidelines does not ensure their implementation and use in clinical practice or policy making. Inequities in health have been defined as those inequalities within or between populations that are avoidable, unnecessary and also unjust and unfair. Evidence-based clinical practice and public health guidelines (‘guidelines’) can be used to target health inequities experienced by disadvantaged populations, although guidelines may unintentionally increase health inequities. For this reason, there is a need for evidence-based clinical practice and public health guidelines to intentionally target health inequities experienced by disadvantaged populations. Current guideline development processes do not include steps for planned implementation of equity-focused guidelines. This article describes nine steps that provide guidance for consideration of equity during guideline implementation. A critical appraisal of the literature followed by a process to build expert consensus was undertaken to define how to include consideration of equity issues during the specific GRADE guideline development process. Using a case study from Colombia we describe nine steps that were used to implement equity-focused GRADE recommendations: (1) identification of disadvantaged groups, (2) quantification of current health inequities, (3) development of equity-sensitive recommendations, (4) identification of key actors for implementation of equity-focused recommendations, (5) identification of barriers and facilitators to the implementation of equity-focused recommendations, (6) development of an equity strategy to be included in the implementation plan, (7) assessment of resources and incentives, (8) development of a communication strategy to support an equity focus and (9) development of monitoring and evaluation strategies. This case study can be used as model for implementing clinical practice guidelines, taking into account equity issues during guideline development and implementation. PMID:29029068

Implementing and Sustaining Team-Based Telecare for Bipolar Disorder: Lessons Learned from a Model-Guided, Mixed Methods Analysis.

PubMed

Bauer, Mark S; Krawczyk, Lois; Tuozzo, Kathy; Frigand, Cara; Holmes, Sally; Miller, Christopher J; Abel, Erica; Osser, David N; Franz, Aleda; Brandt, Cynthia; Rooney, Meghan; Fleming, Jerry; Smith, Eric; Godleski, Linda

2018-01-01

Telemental health interventions have empirical support from clinical trials and structured demonstration projects. However, their implementation and sustainability under less structured clinical conditions are not well demonstrated. We conducted a follow-up analysis of the implementation and sustainability of a clinical video teleconference-based collaborative care model for individuals with bipolar disorder treated in the Department of Veterans Affairs to (a) characterize the extent of implementation and sustainability of the program after its establishment and (b) identify barriers and facilitators to implementation and sustainability. We conducted a mixed methods program evaluation, assessing quantitative aspects of implementation according to the Reach, Efficacy, Adoption, Implementation, and Maintenance implementation framework. We conducted qualitative analysis of semistructured interviews with 16 of the providers who submitted consults, utilizing the Integrated Promoting Action on Research Implementation in the Health Services implementation framework. The program demonstrated linear growth in sites (n = 35) and consults (n = 915) from late 2011 through mid-2016. Site-based analysis indicated statistically significant sustainability beyond the first year of operation. Qualitative analysis identified key facilitators, including consult content, ease of use via electronic health record, and national infrastructure. Barriers included availability of telehealth space, equipment, and staff at the sites, as well as the labor-intensive nature of scheduling. The program achieved continuous growth over almost 5 years due to (1) successfully filling a need perceived by providers, (2) developing in a supportive context, and (3) receiving effective facilitation by national and local infrastructure. Clinical video teleconference-based interventions, even multicomponent collaborative care interventions for individuals with complex mental health conditions, can grow vigorously under appropriate conditions.

Ubiquitous-Severance Hospital Project: Implementation and Results

PubMed Central

Chang, Bung-Chul; Kim, Young-A; Kim, Jee Hea; Jung, Hae Kyung; Kang, Eun Hae; Kang, Hee Suk; Lee, Hyung Il; Kim, Yong Ook; Yoo, Sun Kook; Sunwoo, Ilnam; An, Seo Yong; Jeong, Hye Jeong

2010-01-01

Objectives The purpose of this study was to review an implementation of u-Severance information system with focus on electronic hospital records (EHR) and to suggest future improvements. Methods Clinical Data Repository (CDR) of u-Severance involved implementing electronic medical records (EMR) as the basis of EHR and the management of individual health records. EHR were implemented with service enhancements extending to the clinical decision support system (CDSS) and expanding the knowledge base for research with a repository for clinical data and medical care information. Results The EMR system of Yonsei University Health Systems (YUHS) consists of HP integrity superdome servers using MS SQL as a database management system and MS Windows as its operating system. Conclusions YUHS is a high-performing medical institution with regards to efficient management and customer satisfaction; however, after 5 years of implementation of u-Severance system, several limitations with regards to expandability and security have been identified. PMID:21818425

Ubiquitous-severance hospital project: implementation and results.

PubMed

Chang, Bung-Chul; Kim, Nam-Hyun; Kim, Young-A; Kim, Jee Hea; Jung, Hae Kyung; Kang, Eun Hae; Kang, Hee Suk; Lee, Hyung Il; Kim, Yong Ook; Yoo, Sun Kook; Sunwoo, Ilnam; An, Seo Yong; Jeong, Hye Jeong

2010-03-01

The purpose of this study was to review an implementation of u-Severance information system with focus on electronic hospital records (EHR) and to suggest future improvements. Clinical Data Repository (CDR) of u-Severance involved implementing electronic medical records (EMR) as the basis of EHR and the management of individual health records. EHR were implemented with service enhancements extending to the clinical decision support system (CDSS) and expanding the knowledge base for research with a repository for clinical data and medical care information. The EMR system of Yonsei University Health Systems (YUHS) consists of HP integrity superdome servers using MS SQL as a database management system and MS Windows as its operating system. YUHS is a high-performing medical institution with regards to efficient management and customer satisfaction; however, after 5 years of implementation of u-Severance system, several limitations with regards to expandability and security have been identified.

Nursing journal clubs and the clinical nurse specialist.

PubMed

Westlake, Cheryl; Albert, Nancy M; Rice, Karen L; Bautista, Cynthia; Close, Jackie; Foster, Jan; Timmerman, Gayle M

2015-01-01

The purpose of this article was to describe the clinical nurse specialist's role in developing and implementing a journal club. Tools for critiquing clinical and research articles with an application of each are provided. The journal club provides a forum through which nurses maintain their knowledge base about clinically relevant topics and developments in their specific clinical discipline, analyze and synthesize the relevant scientific literature as evidence, and engage in informal discussions about evidence-based and best practices. The value of journal clubs includes nursing staff education, review of and support for evidence-based practice, promotion of nursing research, and fostering of organization-wide nursing practice changes. The process for establishing a journal club and suggested appraisal tools are discussed. In addition, strategies for overcoming barriers to the implementation of a journal club are outlined. Suggested article review questions and a reporting format for clinical and research articles are provided with examples from 2 articles. Finally, a glossary of terms commonly used by research scientists and manuscript writers are listed and additional resources provided. The clinical nurse specialist's role in developing and implementing a journal club will be facilitated through the use of this article. Enhanced nursing staff education, evidence-based practice, organization-wide nursing practice changes, and nursing research may be conducted following the implementation of a nursing journal club.

The cost of implementing rapid HIV testing in sexually transmitted disease clinics in the United States.

PubMed

Eggman, Ashley A; Feaster, Daniel J; Leff, Jared A; Golden, Matthew R; Castellon, Pedro C; Gooden, Lauren; Matheson, Tim; Colfax, Grant N; Metsch, Lisa R; Schackman, Bruce R

2014-09-01

Rapid HIV testing in high-risk populations can increase the number of persons who learn their HIV status and avoid spending clinic resources to locate persons identified as HIV infected. We determined the cost to sexually transmitted disease (STD) clinics of point-of-care rapid HIV testing using data from 7 public clinics that participated in a randomized trial of rapid testing with and without brief patient-centered risk reduction counseling in 2010. Costs included counselor and trainer time, supplies, and clinic overhead. We applied national labor rates and test costs. We calculated median clinic start-up costs and mean cost per patient tested, and projected incremental annual costs of implementing universal rapid HIV testing compared with current testing practices. Criteria for offering rapid HIV testing and methods for delivering nonrapid test results varied among clinics before the trial. Rapid HIV testing cost an average of US $22/patient without brief risk reduction counseling and US $46/patient with counseling in these 7 clinics. Median start-up costs per clinic were US $1100 and US $16,100 without and with counseling, respectively. Estimated incremental annual costs per clinic of implementing universal rapid HIV testing varied by whether or not brief counseling is conducted and by current clinic testing practices, ranging from a savings of US $19,500 to a cost of US $40,700 without counseling and a cost of US $98,000 to US $153,900 with counseling. Universal rapid HIV testing in STD clinics with same-day results can be implemented at relatively low cost to STD clinics, if brief risk reduction counseling is not offered.

The Instrument for Measuring the Implementation Situation of Traditional Chinese Medicine Guideline: Evaluation and Application

PubMed Central

Wang, Yangyang; Chen, Yaolong; Wang, Xiaoyun; Deng, Jingwen

2017-01-01

Clinical practice guidelines play an important role in reducing the variations in clinical practices and improving the quality of care. To assess the real effect, measuring its implementation situation is needed. The implementation situation can be reflected by testing the consistency between the actual clinical practice and the guideline. We constructed an instrument to measure the implementation situation of Traditional Chinese Medicine (TCM) guideline through consistency testing. The main objectives of our study were to validate the instrument and evaluate the implementation situation of menopause syndrome guideline of TCM, using the data from the consistency test of comparing the medical records with the guideline. A total of 621 cases were included for data analysis. Cronbach's Alpha coefficient is 0.73. The model fit of 7 items in four dimensions was good (SRMR = 0.04; GFI = 0.97; NFI = 0.97; TLI = 0.96; CFI = 0.98; AGFI = 0.90). This instrument is of good reliability and validity. It can help the guideline developers to measure the implementation situation, find the reasons affecting the implementation, and revise the guideline. The method of using consistency test to measure the implementation situation may provide a sample for evaluating the guideline implementation in other fields. PMID:29234379

Implementation of a pharmacist-managed heart failure medication titration clinic.

PubMed

Martinez, Amanda S; Saef, Jerold; Paszczuk, Anna; Bhatt-Chugani, Hetal

2013-06-15

The development, implementation, and initial results of a pharmacist-managed heart failure (HF) medication titration clinic are described. In a quality-improvement initiative at a Veterans Affairs health care system, clinical pharmacists were incorporated into the hospital system's interprofessional outpatient HF clinic. In addition, a separate pharmacist-managed HF medication titration clinic was established, in which pharmacists were granted an advanced scope of practice and prescribing privileges, enabling them to initiate and adjust medication dosages under specific protocols jointly established by cardiology and pharmacy staff. Pharmacists involved in the titration clinic tracked patients' daily body weight, vital signs, and volume status using telephone-monitoring technology and via patient interviews. A retrospective chart review comparing achievement of target doses of angiotensin-converting enzyme inhibitor (ACEI), angiotensin-receptor blocker (ARB), and β-blocker therapies in a group of patients (n = 28) whose dosage titrations were carried out by nurses or physicians prior to implementation of the pharmacist-managed HF medication titration clinic and a group of patients (n = 27) enrolled in the medication titration clinic during its first six months of operation indicated that target ACEI and ARB doses were achieved in a significantly higher percentage of pharmacist-managed titration clinic enrollees (52.9% versus 31%, p = 0.007). Patients enrolled in the pharmacist-managed HF medication titration clinic also had a significantly higher rate of attainment of optimal β-blocker doses (49% versus 24.7%, p = 0.012). Implementation of a pharmacist-managed HF medication titration clinic increased the percentage of patients achieving optimal ACEI, ARB, and β-blocker dosages.

Advancing Evidence-Based Practice in Physical Therapy Settings: Multinational Perspectives on Implementation Strategies and Interventions.

PubMed

Bernhardsson, Susanne; Lynch, Elizabeth; Dizon, Janine Margarita; Fernandes, Jasmin; Gonzalez-Suarez, Consuelo; Lizarondo, Lucylynn; Luker, Julie; Wiles, Louise; Grimmer, Karen

2017-01-01

It is of critical importance that findings from the wealth of clinical physical therapist research are transferred into clinical practice without unnecessary delays. There is a lack of knowledge about strategies that can be used to effectively implement physical therapist research findings and evidence-based practice (EBP) into everyday clinical practice in different national settings and contexts. The purpose of this article is to contribute to knowledge about effective strategies for implementing EBP that have been studied in different national physical therapy settings. The specific aims of this article are to share experiences and provide a current multinational perspective on different approaches and strategies for implementing EBP and to highlight important considerations and implications for both research and practice. Six research studies from various settings in 3 countries are described and synthesized. Key characteristics of the studies and intervention components are tabulated and mapped to the Cochrane Effective Practice and Organisation of Care taxonomy. Commonalities and differences are presented. The implementation strategies described were: a theory-based guideline implementation tailored to identified barriers and facilitators; a multifaceted EBP training package; journal clubs; a multifaceted strategy comprising contextualized procedures, protocols, and standardized resources; barrier identification, education, audit, feedback, and reminders; and contextualized guidelines. Commonalities were the use of a multifaceted approach, educational measures, and clinical guidelines. Key outcomes across the studies were improved attitudes and increased awareness, knowledge, skills, and confidence in EBP; better access to clinical practice guidelines and other EBP resources; identification of barriers that could be targeted in future implementation activities; earlier referrals; and use of recommended outcome measures. The article can serve as a template for other physical therapist researchers in designing implementation studies, as well as to inform policies and practice for health care managers and decision makers who are looking for ways to implement research findings in their organizations. © 2017 American Physical Therapy Association.

Fiery Spirits in the context of institutional entrepreneurship in Swedish healthcare.

PubMed

Eriksson, Nomie; Ujvari, Sandor

2015-01-01

Clinical governance and leadership concepts can lead to more or less successful implementations of new clinical practice. The purpose of this paper is to examine how Fiery Spirits, as institutional entrepreneurs can, working in a team, implement sustained change in hospital clinical practice. This paper describes two case studies, conducted at two Swedish hospitals over a period of two years, in which changes in clinical practice were implemented. In both cases, key-actors, termed Fiery Spirits, played critical roles in these changes. The authors use a qualitative approach and take an intra-organizational perspective with semi-structured in-depth interviews and document analysis. The new clinical practices were successfully implemented with a considerable influence of the Fiery Spirits who played a pivotal role in the change efforts. The Fiery Spirits persuasively, based on their structural and normative legitimacy and the adoption of learning processes, advocated, and supported change. Fiery Spirits, given flexibility and opportunity, can be powerful forces for change outside the trajectory of management-inspired and management-directed change. Team members, when inspired and encouraged by Fiery Spirits, are less resistant to change and more willing to test new clinical practices. The paper complements literature on how the Fiery Spirit concept aligns with concepts of clinical governance and leadership and how change can be achieved. Additionally, the findings show the effects of legitimacy and learning processes on change in clinical practice.

Towards a successful clinical implementation of fluorescence-guided surgery.

PubMed

Snoeks, T J A; van Driel, P B A A; Keereweer, S; Aime, S; Brindle, K M; van Dam, G M; Löwik, C W G M; Ntziachristos, V; Vahrmeijer, A L

2014-04-01

During the European Molecular Imaging Meeting (EMIM) 2013, the fluorescence-guided surgery study group held its inaugural session to discuss the clinical implementation of fluorescence-guided surgery. The general aim of this study group is to discuss and identify the steps required to successfully and safely bring intraoperative fluorescence imaging to the clinics. The focus group intends to use synergies between interested groups as a tool to address regulatory and implementation hurdles in Europe and operates within the intraoperative focus group of the World Molecular Imaging Society (WMIS) that promotes the same interests at the WMIS level. The major topics on the critical path of implementation identified within the study group were quality controls and standards for ensuring accurate imaging and the ability to compare results from different studies, regulatory affairs, and strategies to increase awareness among physicians, regulators, insurance companies, and a broader audience. These hurdles, and the possible actions discussed to overcome them, are summarized in this report. Furthermore, a number of recommendations for the future shape of the fluorescence-guided study group are discussed. A main driving conclusion remains that intraoperative imaging has great clinical potential and that many of the solutions required are best addressed with the community working together to optimally promote and accelerate the clinical implementation of fluorescence imaging towards improving surgical procedures.

Aligning clinical compensation with clinical productivity: design and implementation of the financial value unit (FVU) system in an academic department of internal medicine.

PubMed

Stites, Steven; Steffen, Patrick; Turner, Scott; Pingleton, Susan

2013-07-01

A new metric was developed and implemented at the University of Kansas School of Medicine Department of Internal Medicine, the financial value unit (FVU). This metric analyzes faculty clinical compensation compared with clinical work productivity as a transparent means to decrease the physician compensation variability and compensate faculty equitably for clinical work.The FVU is the ratio of individual faculty clinical compensation compared with their total work relative value units (wRVUs) generated divided by Medical Group Management Association (MGMA) salary to wRVUs of a similar MGMA physician.The closer the FVU ratio is to 1.0, the closer clinical compensation is to that of an MGMA physician with similar clinical productivity. Using FVU metrics to calculate a faculty salary gap compared with MGMA median salary and wRVU productivity, a divisional production payment was established annually.From FY 2006 to FY 2011, both total faculty numbers and overall clinical activity increased. With the implementation of the FVU, both clinical productivity and compensation increased while, at the same time, physician retention rates remained high. Variability in physician compensation decreased. Dramatic clinical growth was associated with the alignment of clinical work and clinical compensation in a transparent and equable process.

Developing knowledge resources to support precision medicine: principles from the Clinical Pharmacogenetics Implementation Consortium (CPIC).

PubMed

Hoffman, James M; Dunnenberger, Henry M; Kevin Hicks, J; Caudle, Kelly E; Whirl Carrillo, Michelle; Freimuth, Robert R; Williams, Marc S; Klein, Teri E; Peterson, Josh F

2016-07-01

To move beyond a select few genes/drugs, the successful adoption of pharmacogenomics into routine clinical care requires a curated and machine-readable database of pharmacogenomic knowledge suitable for use in an electronic health record (EHR) with clinical decision support (CDS). Recognizing that EHR vendors do not yet provide a standard set of CDS functions for pharmacogenetics, the Clinical Pharmacogenetics Implementation Consortium (CPIC) Informatics Working Group is developing and systematically incorporating a set of EHR-agnostic implementation resources into all CPIC guidelines. These resources illustrate how to integrate pharmacogenomic test results in clinical information systems with CDS to facilitate the use of patient genomic data at the point of care. Based on our collective experience creating existing CPIC resources and implementing pharmacogenomics at our practice sites, we outline principles to define the key features of future knowledge bases and discuss the importance of these knowledge resources for pharmacogenomics and ultimately precision medicine. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Implementing community-based provider participation in research: an empirical study

PubMed Central

2012-01-01

Background Since 2003, the United States National Institutes of Health (NIH) has sought to restructure the clinical research enterprise in the United States by promoting collaborative research partnerships between academically-based investigators and community-based physicians. By increasing community-based provider participation in research (CBPPR), the NIH seeks to advance the science of discovery by conducting research in clinical settings where most people get their care, and accelerate the translation of research results into everyday clinical practice. Although CBPPR is seen as a promising strategy for promoting the use of evidence-based clinical services in community practice settings, few empirical studies have examined the organizational factors that facilitate or hinder the implementation of CBPPR. The purpose of this study is to explore the organizational start-up and early implementation of CBPPR in community-based practice. Methods We used longitudinal, case study research methods and an organizational model of innovation implementation to theoretically guide our study. Our sample consisted of three community practice settings that recently joined the National Cancer Institute’s (NCI) Community Clinical Oncology Program (CCOP) in the United States. Data were gathered through site visits, telephone interviews, and archival documents from January 2008 to May 2011. Results The organizational model for innovation implementation was useful in identifying and investigating the organizational factors influencing start-up and early implementation of CBPPR in CCOP organizations. In general, the three CCOP organizations varied in the extent to which they achieved consistency in CBPPR over time and across physicians. All three CCOP organizations demonstrated mixed levels of organizational readiness for change. Hospital management support and resource availability were limited across CCOP organizations early on, although they improved in one CCOP organization. As a result of weak IPPs, all three CCOPs created a weak implementation climate. Patient accrual became concentrated over time among those groups of physicians for whom CBPPR exhibited a strong innovation-values fit. Several external factors influenced innovation use, complicating and enriching our intra-organizational model of innovation implementation. Conclusion Our results contribute to the limited body of research on the implementation of CBPPR. They inform policy discussions about increasing and sustaining community clinician involvement in clinical research and expand on theory about organizational determinants of implementation effectiveness. PMID:22568935

Institutional Profile: University of Chicago Center for Personalized Therapeutics: research, education and implementation science.

PubMed

Dolan, M Eileen; Maitland, Michael L; O'Donnell, Peter H; Nakamura, Yusuke; Cox, Nancy J; Ratain, Mark J

2013-09-01

Pharmacogenomics is aimed at advancing our knowledge of the genetic basis of variable drug response. The Center for Personalized Therapeutics within the University of Chicago comprises basic, translational and clinical research as well as education including undergraduate, graduate, medical students, clinical/postdoctoral fellows and faculty. The Committee on Clinical Pharmacology and Pharmacogenomics is the educational arm of the Center aimed at training clinical and postdoctoral fellows in translational pharmacology and pharmacogenomics. Research runs the gamut from basic discovery and functional studies to pharmacogenomic implementation studies to evaluate physician adoption of genetic medicine. The mission of the Center is to facilitate research, education and implementation of pharmacogenomics to realize the true potential of personalized medicine and improve the lives of patients.

Mandatory implementation of NICE Guidelines for the care of bipolar disorder and other conditions in England and Wales.

PubMed

Morriss, Richard

2015-09-30

Bipolar disorder is a common long-term mental health condition characterised by episodes of mania or hypomania and depression resulting in disability, early death, and high health and society costs. Public money funds the National Institute of Healthcare and Clinical Excellence (NICE) to produce clinical guidelines by systematically identifying the most up to date research evidence and costing its main recommendations for healthcare organisations and professionals to follow in England and Wales. Most governments, including those of England and Wales, need to improve healthcare but at reduced cost. There is evidence, particularly in bipolar disorder, that systematically following clinical guidelines achieves these outcomes. NICE clinical guidelines, including those regarding bipolar disorder, remain variably implemented. They give clinicians and patients a non-prescriptive basis for deciding their care. Despite the passing of the Health and Social Care Act in 2012 in England requiring all healthcare organisations to consider NICE clinical guidelines in commissioning, delivering, and inspecting healthcare services, healthcare organisations in the National Health Service may ignore them with little accountability and few consequences. There is no mechanism to ensure that healthcare professionals know or consider them. Barriers to their implementation include the lack of political and professional leadership, the complexity of the organisation of care and policy, mistrust of some processes and recommendations of clinical guidelines, and a lack of a clear implementation model, strategy, responsibility, or accountability. Mitigation to these barriers is presented herein. The variability, safety, and quality of healthcare might be improved and its cost reduced if the implementation of NICE clinical guidelines, such as those for bipolar disorder, were made the minimum starting point for clinical decision-making and mandatory responsibilities of all healthcare organisations and professionals.

The clinical database and implementation of treatment guidelines by the Danish Breast Cancer Cooperative Group in 2007-2016.

PubMed

Jensen, Maj-Britt; Laenkholm, Anne-Vibeke; Offersen, Birgitte V; Christiansen, Peer; Kroman, Niels; Mouridsen, Henning T; Ejlertsen, Bent

2018-01-01

Since 40 years, Danish Breast Cancer Cooperative Group (DBCG) has provided comprehensive guidelines for diagnosis and treatment of breast cancer. This population-based analysis aimed to describe the plurality of modifications introduced over the past 10 years in the national Danish guidelines for the management of early breast cancer. By use of the clinical DBCG database we analyze the effectiveness of the implementation of guideline revisions in Denmark. From the DBCG guidelines we extracted modifications introduced in 2007-2016 and selected examples regarding surgery, radiotherapy (RT) and systemic treatment. We assessed introduction of modifications from release on the DBCG webpage to change in clinical practice using the DBCG clinical database. Over a 10-year period data from 48,772 patients newly diagnosed with malignant breast tumors were entered into DBCG's clinical database and 42,197 of these patients were diagnosed with an invasive carcinoma following breast conserving surgery (BCS) or mastectomy. More than twenty modifications were introduced in the guidelines. Implementations, based on prospectively collected data, varied widely; exemplified with around one quarter of the patients not treated according to a specific guideline within one year from the introduction, to an almost immediate full implantation. Modifications of the DBCG guidelines were generally well implemented, but the time to full implementation varied from less than one year up to around five years. Our data is registry based and does not allow a closer analysis of the causes for delay in implementation of guideline modifications.

Conceptualizing clinical nurse leader practice: an interpretive synthesis.

PubMed

Bender, Miriam

2016-01-01

The Institute of Medicine's Future of Nursing report identifies the clinical nurse leader as an innovative new role for meeting higher health-care quality standards. However, specific clinical nurse leader practices influencing documented quality outcomes remain unclear. Lack of practice clarity limits the ability to articulate, implement and measure clinical nurse leader-specific practice and quality outcomes. Interpretive synthesis design and grounded theory analysis were used to develop a theoretical understanding of clinical nurse leader practice that can facilitate systematic and replicable implementation across health-care settings. The core phenomenon of clinical nurse leader practice is continuous clinical leadership, which involves four fundamental activities: facilitating effective ongoing communication; strengthening intra and interprofessional relationships; building and sustaining teams; and supporting staff engagement. Clinical nurse leaders continuously communicate and develop relationships within and across professions to promote and sustain information exchange, engagement, teamwork and effective care processes at the microsystem level. Clinical nurse leader-integrated care delivery systems highlight the benefits of nurse-led models of care for transforming health-care quality. Managers can use this study's findings to frame an implementation strategy that addresses theoretical domains of clinical nurse leader practice to help ensure practice success. © 2015 John Wiley & Sons Ltd.

Implementation of Venous Thromboembolism Prophylaxis Guidelines in Clinical Practice: A Retrospective Study in Two Croatian Hospitals.

PubMed

Marušić, Srećko; Knežević, Aleksandar; Bačić Vrca, Vesna; Marinović, Ivana; Bačić, Julija; Obreli Neto, Paulo Roque; Amidžić Klarić, Daniela; Diklić, Dijaneta

2017-12-01

The aim of this study was to evaluate the implementation of the 9th edition of the American College of Chest Physicians (ACCP9) guidelines for prevention of venous thromboembolism in nonsurgical patients in clinical practice in one university and one general Croatian hospital. A retrospective study was conducted at Zadar General Hospital from Zadar and Dubrava University Hospital from Zagreb. Medical charts of all patients admitted to Medical Departments in two periods, before and after implementation of the ACCP9 guidelines, were analyzed. The ACCP9 guidelines were made available to all physicians through the hospital electronic information system immediately after the publication. The Hospital Drug Committees promoted implementation of the guidelines during their periodical clinical visits. Overall, 850 patients were included in the study in two periods. There was no statistically significant difference in the number of high-risk patients receiving thromboprophylaxis after the guidelines implementation in either hospital. In both periods, a signifi-cantly higher number of high-risk patients received thromboprophylaxis in Dubrava University Hos-pital in comparison with Zadar General Hospital (31.7% vs. 3.8% and 40.3% vs. 7.3%, respectively; p<0.001). This study revealed insufficient implementation of evidence-based thromboprophylaxis guidelines in clinical practice in two Croatian hospitals.

Pilot Study of Implementation of an Internet-Based Depression Prevention Intervention (CATCH-IT) for Adolescents in 12 US Primary Care Practices: Clinical and Management/Organizational Behavioral Perspectives

PubMed Central

Eisen, Jeffrey C.; Marko-Holguin, Monika; Fogel, Joshua; Cardenas, Alonso; Bahn, My; Bradford, Nathan; Fagan, Blake; Wiedmann, Peggy

2013-01-01

Objective: To explore the implementation of CATCH-IT (Competent Adulthood Transition with Cognitive-behavioral Humanistic and Interpersonal Training), an Internet-based depression intervention program in 12 primary care sites, occurring as part of a randomized clinical trial comparing 2 versions of the intervention (motivational interview + Internet program versus brief advice + Internet program) in 83 adolescents aged 14 to 21 years recruited from February 1, 2007, to November 31, 2007. Method: The CATCH-IT intervention model consists of primary care screening to assess risk, a primary care physician interview to encourage participation, and 14 online modules of Internet training to teach adolescents how to reduce behaviors that increase vulnerability to depressive disorders. Specifically, we evaluated this program from both a management/organizational behavioral perspective (provider attitudes and demonstrated competence) and a clinical outcomes perspective (depressed mood scores) using the RE-AIM model (Reach, Efficacy, Adoption, Implementation, and Maintenance of the intervention). Results: While results varied by clinic, overall, clinics demonstrated satisfactory reach, efficacy, adoption, implementation, and maintenance of the CATCH-IT depression prevention program. Measures of program implementation and management predicted clinical outcomes at practices in exploratory analyses. Conclusion: Multidisciplinary approaches may be essential to evaluating the impact of complex interventions to prevent depression in community settings. Primary care physicians and nurses can use Internet-based programs to create a feasible and cost-effective model for the prevention of mental disorders in adolescents in primary care settings. Trial Registration: ClinicalTrials.gov identifiers: NCT00152529 and NCT00145912 PMID:24800110

Are they ready? Organizational readiness for change among clinical teaching teams

PubMed Central

Bank, Lindsay; Jippes, Mariëlle; Leppink, Jimmie; Scherpbier, Albert JJA; den Rooyen, Corry; van Luijk, Scheltus J; Scheele, Fedde

2017-01-01

Introduction Curriculum change and innovation are inevitable parts of progress in postgraduate medical education (PGME). Although implementing change is known to be challenging, change management principles are rarely looked at for support. Change experts contend that organizational readiness for change (ORC) is a critical precursor for the successful implementation of change initiatives. Therefore, this study explores whether assessing ORC in clinical teaching teams could help to understand how curriculum change takes place in PGME. Methods Clinical teaching teams in hospitals in the Netherlands were requested to complete the Specialty Training’s Organizational Readiness for curriculum Change, a questionnaire to measure ORC in clinical teaching teams. In addition, change-related behavior was measured by using the “behavioral support-for-change” measure. A two-way analysis of variance was performed for all response variables of interest. Results In total, 836 clinical teaching team members were included in this study: 288 (34.4%) trainees, 307 (36.7%) clinical staff members, and 241 (28.8%) program directors. Overall, items regarding whether the program director has the authority to lead scored higher compared with the other items. At the other end, the subscales “management support and leadership,” “project resources,” and “implementation plan” had the lowest scores in all groups. Discussion The study brought to light that program directors are clearly in the lead when it comes to the implementation of educational innovation. Clinical teaching teams tend to work together as a team, sharing responsibilities in the implementation process. However, the results also reinforce the need for change management support in change processes in PGME. PMID:29276424

Pilot Study of Implementation of an Internet-Based Depression Prevention Intervention (CATCH-IT) for Adolescents in 12 US Primary Care Practices: Clinical and Management/Organizational Behavioral Perspectives.

PubMed

Eisen, Jeffrey C; Marko-Holguin, Monika; Fogel, Joshua; Cardenas, Alonso; Bahn, My; Bradford, Nathan; Fagan, Blake; Wiedmann, Peggy; Van Voorhees, Benjamin W

2013-01-01

To explore the implementation of CATCH-IT (Competent Adulthood Transition with Cognitive-behavioral Humanistic and Interpersonal Training), an Internet-based depression intervention program in 12 primary care sites, occurring as part of a randomized clinical trial comparing 2 versions of the intervention (motivational interview + Internet program versus brief advice + Internet program) in 83 adolescents aged 14 to 21 years recruited from February 1, 2007, to November 31, 2007. The CATCH-IT intervention model consists of primary care screening to assess risk, a primary care physician interview to encourage participation, and 14 online modules of Internet training to teach adolescents how to reduce behaviors that increase vulnerability to depressive disorders. Specifically, we evaluated this program from both a management/organizational behavioral perspective (provider attitudes and demonstrated competence) and a clinical outcomes perspective (depressed mood scores) using the RE-AIM model (Reach, Efficacy, Adoption, Implementation, and Maintenance of the intervention). While results varied by clinic, overall, clinics demonstrated satisfactory reach, efficacy, adoption, implementation, and maintenance of the CATCH-IT depression prevention program. Measures of program implementation and management predicted clinical outcomes at practices in exploratory analyses. Multidisciplinary approaches may be essential to evaluating the impact of complex interventions to prevent depression in community settings. Primary care physicians and nurses can use Internet-based programs to create a feasible and cost-effective model for the prevention of mental disorders in adolescents in primary care settings. ClinicalTrials.gov identifiers: NCT00152529 and NCT00145912.

Implementing clinical governance in English primary care groups/trusts: reconciling quality improvement and quality assurance

PubMed Central

Campbell, S; Sheaff, R; Sibbald, B; Marshall, M; Pickard, S; Gask, L; Halliwell, S; Rogers, A; Roland, M

2002-01-01

Objectives: To investigate the concept of clinical governance being advocated by primary care groups/trusts (PCG/Ts), approaches being used to implement clinical governance, and potential barriers to its successful implementation in primary care. Design: Qualitative case studies using semi-structured interviews and documentation review. Setting: Twelve purposively sampled PCG/Ts in England. Participants: Fifty senior staff including chief executives, clinical governance leads, mental health leads, and lay board members. Main outcome measures: Participants' perceptions of the role of clinical governance in PCG/Ts. Results: PCG/Ts recognise that the successful implementation of clinical governance in general practice will require cultural as well as organisational changes, and the support of practices. They are focusing their energies on supporting practices and getting them involved in quality improvement activities. These activities include, but move beyond, conventional approaches to quality assessment (audit, incentives) to incorporate approaches which emphasise corporate and shared learning. PCG/Ts are also engaged in setting up systems for monitoring quality and for dealing with poor performance. Barriers include structural barriers (weak contractual levers to influence general practices), resource barriers (perceived lack of staff or money), and cultural barriers (suspicion by practice staff or problems overcoming the perceived blame culture associated with quality assessment). Conclusion: PCG/Ts are focusing on setting up systems for implementing clinical governance which seek to emphasise developmental and supportive approaches which will engage health professionals. Progress is intentionally incremental but formidable challenges lie ahead, not least reconciling the dual role of supporting practices while monitoring (and dealing with poor) performance. PMID:12078380

Are they ready? Organizational readiness for change among clinical teaching teams.

PubMed

Bank, Lindsay; Jippes, Mariëlle; Leppink, Jimmie; Scherpbier, Albert Jja; den Rooyen, Corry; van Luijk, Scheltus J; Scheele, Fedde

2017-01-01

Curriculum change and innovation are inevitable parts of progress in postgraduate medical education (PGME). Although implementing change is known to be challenging, change management principles are rarely looked at for support. Change experts contend that organizational readiness for change (ORC) is a critical precursor for the successful implementation of change initiatives. Therefore, this study explores whether assessing ORC in clinical teaching teams could help to understand how curriculum change takes place in PGME. Clinical teaching teams in hospitals in the Netherlands were requested to complete the Specialty Training's Organizational Readiness for curriculum Change, a questionnaire to measure ORC in clinical teaching teams. In addition, change-related behavior was measured by using the "behavioral support-for-change" measure. A two-way analysis of variance was performed for all response variables of interest. In total, 836 clinical teaching team members were included in this study: 288 (34.4%) trainees, 307 (36.7%) clinical staff members, and 241 (28.8%) program directors. Overall, items regarding whether the program director has the authority to lead scored higher compared with the other items. At the other end, the subscales "management support and leadership," "project resources," and "implementation plan" had the lowest scores in all groups. The study brought to light that program directors are clearly in the lead when it comes to the implementation of educational innovation. Clinical teaching teams tend to work together as a team, sharing responsibilities in the implementation process. However, the results also reinforce the need for change management support in change processes in PGME.

Clinical Decision Support to Implement CYP2D6 Drug-Gene Interaction.

PubMed

Caraballo, Pedro J; Parkulo, Mark; Blair, David; Elliott, Michelle; Schultz, Cloann; Sutton, Joseph; Rao, Padma; Bruflat, Jamie; Bleimeyer, Robert; Crooks, John; Gabrielson, Donald; Nicholson, Wayne; Rohrer Vitek, Carolyn; Wix, Kelly; Bielinski, Suzette J; Pathak, Jyotishman; Kullo, Iftikhar

2015-01-01

The level of CYP2D6 metabolic activity can be predicted by pharmacogenomic testing, and concomitant use of clinical decision support has the potential to prevent adverse effects from those drugs metabolized by this enzyme. Our initial findings after implementation of clinical decision support alerts integrated in the electronic health records suggest high feasibility, but also identify important challenges.

Enhancing system-wide implementation of opioid prescribing guidelines in primary care: protocol for a stepped-wedge quality improvement project.

PubMed

Zgierska, Aleksandra E; Vidaver, Regina M; Smith, Paul; Ales, Mary W; Nisbet, Kate; Boss, Deanne; Tuan, Wen-Jan; Hahn, David L

2018-06-05

Systematic implementation of guidelines for opioid therapy management in chronic non-cancer pain can reduce opioid-related harms. However, implementation of guideline-recommended practices in routine care is subpar. The goal of this quality improvement (QI) project is to assess whether a clinic-tailored QI intervention improves the implementation of a health system-wide, guideline-driven policy on opioid prescribing in primary care. This manuscript describes the protocol for this QI project. A health system with 28 primary care clinics caring for approximately 294,000 primary care patients developed and implemented a guideline-driven policy on long-term opioid therapy in adults with opioid-treated chronic non-cancer pain (estimated N = 3980). The policy provided multiple recommendations, including the universal use of treatment agreements, urine drug testing, depression and opioid misuse risk screening, and standardized documentation of the chronic pain diagnosis and treatment plan. The project team drew upon existing guidelines, feedback from end-users, experts and health system leadership to develop a robust QI intervention, targeting clinic-level implementation of policy-directed practices. The resulting multi-pronged QI intervention included clinic-wide and individual clinician-level educational interventions. The QI intervention will augment the health system's "routine rollout" method, consisting of a single educational presentation to clinicians in group settings and a separate presentation for staff. A stepped-wedge design will enable 9 primary care clinics to receive the intervention and assessment of within-clinic and between-clinic changes in adherence to the policy items measured by clinic-level electronic health record-based measures and process measures of the experience with the intervention. Developing methods for a health system-tailored QI intervention required a multi-step process to incorporate end-user feedback and account for the needs of targeted clinic team members. Delivery of such tailored QI interventions has the potential to enhance uptake of opioid therapy management policies in primary care. Results from this study are anticipated to elucidate the relative value of such QI activities.

Improved clinical documentation leads to superior reportable outcomes: An accurate representation of patient's clinical status.

PubMed

Elkbuli, Adel; Godelman, Steven; Miller, Ashley; Boneva, Dessy; Bernal, Eileen; Hai, Shaikh; McKenney, Mark

2018-05-01

Clinical documentation can be an underappreciated. Trauma Centers (TCs) are now routinely evaluated for quality performance. TCs with poor documentation may not accurately reflect actual injury burden or comorbidities and can impact accuracy of mortality measures. Markers exist to adjust crude death rates for injury severity: observed over expected deaths (O/E) adjust for injury; Case Mix Index (CMI) reflects disease burden, and Severity of Illness (SOI) measures organ dysfunction. We aim to evaluate the impact of implementing a Clinical Documentation Improvement Program (CDIP) on reported outcomes. Review of 2-years of prospectively collected data for trauma patients, during the implementation of CDIP. A two-group prospective observational study design was used to evaluate the pre-implementation and the post-implementation phase of improved clinical documentation. T-test and Chi-Squared were used with significance defined as p < 0.05. In the pre-implementation period, there were 49 deaths out of 1419 (3.45%), while post-implementation period, had 38 deaths out of 1454 (2.61%), (non-significant). There was however, a significant difference between O/E ratios. In the pre-phase, the O/E was 1.36 and 0.70 in the post-phase (p < 0.001). The two groups also differed on CMI with a pre-group mean of 2.48 and a post-group of 2.87 (p < 0.001), indicating higher injury burden in the post-group. SOI started at 2.12 and significantly increased to 2.91, signifying more organ system dysfunction (p < 0.018). Improved clinical documentation results in improved accuracy of measures of mortality, injury severity, and comorbidities and a more accurate reflection in O/E mortality ratios, CMI, and SOI. Copyright © 2018 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Athletic Training Student Core Competency Implementation During Patient Encounters.

PubMed

Cavallario, Julie M; Van Lunen, Bonnie L; Hoch, Johanna M; Hoch, Matthew; Manspeaker, Sarah A; Pribesh, Shana L

2018-03-01

  Health care research evidence suggests that early patient encounters (PEs), as well as the purposeful implementation of professional core competencies (CCs), for athletic training students (ATSs) may be beneficial to their ability to provide care. However, no investigators have related facets of the clinical education experience with CC implementation as a form of summative assessment of the clinical experience.   To determine the relationship between the frequency and length of PEs, as well as the student's role and clinical site during PEs, and the students' perceived CC implementation during these encounters.   Cross-sectional study.   Professional athletic training program, National Collegiate Athletic Association Division I institution.   We purposefully recruited 1 athletic training program that used E*Value software; 40 participants (31 females, 9 males) enrolled in the professional phase (12 first year, 14 second year, 14 third year) participated.   Participants viewed a 20-minute recorded CC educational module followed by educational handouts, which were also posted online for reference throughout the semester. The E*Value software was used to track PEs, including the type of encounter (ie, actual patient, practice encounter, didactic practice scenario), the type of site where the encounter occurred (university, high school), and the participant's role (observed, assisted, performed), as well as responses to an added block of questions indicating which, if any, of the CCs were implemented during the PE.   Variables per patient were PE length (minutes), participant role, site at which the encounter occurred, and whether any of the 6 CCs were implemented ( yes/ no). Variables per participant were average encounter length (minutes), encounter frequency, modal role, clinical site assignment, and the number of times each CC was implemented. Separate 1-way analyses of variance were used to examine the relationships between role or clinical site and implementation of total number of CCs. Multiple linear regressions were used to determine how the average length and frequency of PEs were related to the average and total number of implemented CCs. Binary logistic regression models indicated how the length of each encounter, role of the participant, and type of clinical site related to the implementation of each CC.   The roles of participants during PEs were related to their ability to implement the total number of CCs ( F = 103.48, P < .001). Those who observed were likely to implement fewer total CCs than those who assisted (M diff = -0.29, P < .001); those who assisted were likely to implement more total CCs than those who performed (M diff = 0.32, P < .001). Frequency of encounters was the only significant variable in the model examining all independent variables with CC implementation ( b 4,32 = 3.34, t = 9.46, P < .001).   The role of the student, namely assisting during PEs, and the volume of PEs should be considered priorities for students to promote greater CC implementation.

Mayo Clinic Jacksonville electronic radiology practice

NASA Astrophysics Data System (ADS)

Morin, Richard L.; Berquist, Thomas H.; Rueger, Wolfgang

1996-05-01

We have begun a project to implement an Electronic (Filmless) Radiology Practice (ERP) at Mayo Clinic Jacksonville. This project is integrated with the implementation of a project (Automated Clinical Practice--ACP) to eliminate circulation and archival of the current paper Medical Record. The ERP will result in elimination of screen/film radiography and the transmittal of film throughout the institution by the end of 1996. In conjunction with the ACP, paper and film will not circulate within the clinic by the end of this year.

Implementation of a PACS for radiography training and clinical service in a university setting through a multinational effort

NASA Astrophysics Data System (ADS)

Tang, Fuk-hay; Law, Yuen Y.; Zhang, Jianguo; Liu, Hai L.; Chang, Tony; Matsuda, Koyo; Cao, Fei

2001-08-01

The Hong Kong Polytechnic University has a Radiography Division under the Development of Optometry and Radiography. The Division trains both diagnostic and therapeutic radiographers with 60 students/year and offers a B.Sc. degree. In addition the Division together with the University Health Service operates a radiography clinic with radiology consultation from radiologists from other hospitals and clinics. This paper describers the implementation of a PACS in the Division for radiography training, and for clinical service.

Development and implementation of a psychotherapy tracking database in primary care.

PubMed

Craner, Julia R; Sawchuk, Craig N; Mack, John D; LeRoy, Michelle A

2017-06-01

Although there is a rapid increase in the integration of behavioral health services in primary care, few studies have evaluated the effectiveness of these services in real-world clinical settings, in part due to the difficulty of translating traditional mental health research designs to this setting. Accordingly, innovative approaches are needed to fit the unique challenges of conducting research in primary care. The development and implementation of one such approach is described in this article. A continuously populating database for psychotherapy services was implemented across 5 primary care clinics in a large health system to assess several levels of patient care, including service utilization, symptomatic outcomes, and session-by-session use of psychotherapy principles by providers. Each phase of implementation revealed challenges, including clinician time, dissemination to clinics with different resources, and fidelity of data collection strategy across providers, as well as benefits, including the generation of useful data to inform clinical care, program development, and empirical research. The feasible and sustainable implementation of data collection for routine clinical practice in primary care has the potential to fuel the evidence base around integrated care. The current project describes the development of an innovative approach that, with further empirical study and refinement, could enable health care professionals and systems to understand their population and clinical process in a way that addresses essential gaps in the integrated care literature. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The Effectiveness of Ultra-Low Magnitude Reinforcers: Findings From a "Real-World" Application of Contingency Management.

PubMed

Kropp, Frankie; Lewis, Daniel; Winhusen, Theresa

2017-01-01

Research has consistently found contingency management (CM) to be an effective tool in increasing desired patient behaviors in substance use disorder (SUD) treatment. Despite the strong evidence for the effectiveness of this intervention, practical issues and the cost of implementing CM in treatment programs have been significant barriers to adoption. To evaluate the impact of a CM program designed and implemented by university-affiliated methadone clinic staff to increase patient group attendance. The CM program consisted of a weekly raffle for patients attending clinician-led group counseling and/or in-clinic Methadone Anonymous (MA) groups in which slips with patient ID#s were entered and one ID slip was drawn per week with a fee credit for a dose of methadone ($15) as the prize. The CM program continued for 12 months. Group attendance was tracked before, during, and after CM implementation as part of ongoing clinic service utilization monitoring. Following the implementation of CM, attendance at any clinician-led or MA groups increased significantly from baseline to month 1 (X 2 =5.78, p<0.05) but this increase was not sustained beyond month 6. Analysis of attendance by type of group revealed that clinician-led group attendance did not increase significantly but there was a significant increase in in-clinic MA group attendance from baseline to month 1 (X 2 =20.27, p<0.001), which was sustained through the 12-month implementation period (X 2 =11.21, p<0.001) and through 3 months post-implementation (X 2 =14.73; p<0.001). A low-cost, simple CM intervention implemented by clinic staff was associated with significant increases in the target behavior of increasing group attendance. Copyright © 2016 Elsevier Inc. All rights reserved.

Successful Implementation of Clinical Information Technology: Seven Key Lessons from CPOE.

PubMed

Gellert, G A; Hill, V; Bruner, K; Maciaz, G; Saucedo, L; Catzoela, L; Ramirez, R; Jacobs, W J; Nguyen, P; Patel, L; Webster, S L

2015-01-01

To identify and describe the most critical strategic and operational contributors to the successful implementation of clinical information technologies, as deployed within a moderate sized system of U.S. community hospitals. CHRISTUS Health is a multi-state system comprised of more than 350 services and 60 hospitals with over 9 000 physicians. The Santa Rosa region of CHRISTUS Health, located in greater San Antonio, Texas is comprised of three adult community hospital facilities and one Children's hospital each with bed capacities of 142-180. Computerized Patient Order Entry (CPOE) was first implemented in 2012 within a complex market environment. The Santa Rosa region has 2 417 credentialed physicians and 263 mid-level allied health professionals. This report focuses on the seven most valuable strategies deployed by the Health Informatics team in a large four hospital CHRISTUS region to achieve strong CPOE adoption and critical success lessons learned. The findings are placed within the context of the literature describing best practices in health information technology implementation. While the elements described involved discrete de novo process generation to support implementation and operations, collectively they represent the creation of a new customer-centric service culture in our Health Informatics team, which has served as a foundation for ensuring strong clinical information technology adoption beyond CPOE. The seven success factors described are not limited in their value to and impact on CPOE adoption, but generalize to - and can advance success in - varied other clinical information technology implementations across diverse hospitals. A number of these factors are supported by reports in the literature of other institutions' successful implementations of CPOE and other clinical information technologies, and while not prescriptive to other settings, may be adapted to yield value elsewhere.

Looking good or doing better? Patterns of decoupling in the implementation of clinical directorates.

PubMed

Mascia, Daniele; Morandi, Federica; Cicchetti, Americo

2014-01-01

The interest toward hospital restructuring has risen significantly in recent years. In spite of its potential benefits, often organizational restructuring in health care produces unexpected consequences. Extant research suggests that institutional theory provides a powerful theoretical lens through which hospital restructuring can be described and explained. According to this perspective, the effectiveness of change is strongly related to the extent to which innovative arrangements, tools, or practices are adopted and implemented within hospitals. Whenever these new arrangements require a substantial modification of internal processes and practices, resistance to implementation emerges and organizational change is likely to become neutralized. This study analyzes how hospital organizations engage in decoupling by adopting but not implementing a new organizational model named clinical directorate. We collected primary data on the diffusion of the clinical directorate model, which was mandated by law in the Italian National Health Service to improve hospital services. We surveyed the adoption and implementation of the clinical directorate model by monitoring the presence of clinical governance tools (measures for the quality improvement of hospital services) within single directorates. In particular, we compared hospitals that adopted the model before (early adopters) or after (later adopters) the mandate was introduced. Hospitals were engaged in decoupling by adopting the new arrangement but not implementing internal practices and tools for quality improvement. The introduction of the law significantly affected the decoupling, with late-adopter hospitals being less likely to implement the adopted model. The present research shows that changes in quality improvement processes may vary in relation to policy makers' interventions aimed at boosting the adoption of new hospital arrangements. Hospital administrators need to be aware and identify the institutional changes that might be driven by law to be able to react consistently with expectations of policymakers.

Acceptance testing for PACS: from methodology to design to implementation

NASA Astrophysics Data System (ADS)

Liu, Brent J.; Huang, H. K.

2004-04-01

Acceptance Testing (AT) is a crucial step in the implementation process of a PACS within a clinical environment. AT determines whether the PACS is ready for clinical use and marks the official sign off of the PACS product. Most PACS vendors have Acceptance Testing (AT) plans, however, these plans do not provide a complete and robust evaluation of the full system. In addition, different sites will have different special requirements that vendor AT plans do not cover. The purpose of this paper is to introduce a protocol for AT design and present case studies of AT performed on clinical PACS. A methodology is presented that includes identifying testing components within PACS, quality assurance for both functionality and performance, and technical testing focusing on key single points-of-failure within the PACS product. Tools and resources that provide assistance in performing AT are discussed. In addition, implementation of the AT within the clinical environment and the overall implementation timeline of the PACS process are presented. Finally, case studies of actual AT of clinical PACS performed in the healthcare environment will be reviewed. The methodology for designing and implementing a robust AT plan for PACS was documented and has been used in PACS acceptance tests in several sites. This methodology can be applied to any PACS and can be used as a validation for the PACS product being acquired by radiology departments and hospitals. A methodology for AT design and implementation was presented that can be applied to future PACS installations. A robust AT plan for a PACS installation can increase both the utilization and satisfaction of a successful implementation of a PACS product that benefits both vendor and customer.

Practice, science and governance in interaction: European effort for the system-wide implementation of the International Classification of Functioning, Disability and Health (ICF) in Physical and Rehabilitation Medicine.

PubMed

Stucki, Gerold; Zampolini, Mauro; Juocevicius, Alvydas; Negrini, Stefano; Christodoulou, Nicolas

2017-04-01

Since its launch in 2001, relevant international, regional and national PRM bodies have aimed to implement the International Classification of Functioning, Disability and Health (ICF) in Physical and Rehabilitation Medicine (PRM), whereby contributing to the development of suitable practical tools. These tools are available for implementing the ICF in day-to-day clinical practice, standardized reporting of functioning outcomes in quality management and research, and guiding evidence-informed policy. Educational efforts have reinforced PRM physicians' and other rehabilitation professionals' ICF knowledge, and numerous implementation projects have explored how the ICF is applied in clinical practice, research and policy. Largely lacking though is the system-wide implementation of ICF in day-to-day practice across all rehabilitation services of national health systems. In Europe, system-wide implementation of ICF requires the interaction between practice, science and governance. Considering its mandate, the UEMS PRM Section and Board have decided to lead a European effort towards system-wide ICF implementation in PRM, rehabilitation and health care at large, in interaction with governments, non-governmental actors and the private sector, and aligned with ISPRM's collaboration plan with WHO. In this paper we present the current PRM internal and external policy agenda towards system-wide ICF implementation and the corresponding implementation action plan, while highlighting priority action steps - promotion of ICF-based standardized reporting in national quality management and assurance programs, development of unambiguous rehabilitation service descriptions using the International Classification System for Service Organization in Health-related Rehabilitation, development of Clinical Assessment Schedules, qualitative linkage and quantitative mapping of data to the ICF, and the cultural adaptation of the ICF Clinical Data Collection Tool in European languages.

Study protocol of an economic evaluation of an extended implementation strategy for the treatment of low back pain in general practice: a cluster randomised controlled trial.

PubMed

Jensen, Cathrine Elgaard; Riis, Allan; Pedersen, Kjeld Møller; Jensen, Martin Bach; Petersen, Karin Dam

2014-10-08

In Denmark, guidelines on low back pain management are currently being implemented; in association with this, a clinical trial is conducted. A health economic evaluation is carried out alongside the clinical trial to assess the cost-effectiveness of an extended implementation strategy to increase the general practitioners' adherence to the guidelines. In addition to usual dissemination, the extended implementation strategy is composed of visits from a guideline facilitator, stratification tools, and feedback on guideline adherence. The aim of this paper is to provide the considerations on the design of the health economic evaluation. The economic evaluation is carried out alongside a cluster randomised controlled trial consisting of 60 general practices in the North Denmark Region. An expected 1,200 patients between the age of 18 and 65 years with a low back pain diagnosis will be enrolled. The economic evaluation comprises both a cost-effectiveness analyses and a cost-utility analysis. Effectiveness measures include referral to secondary care, health-related quality of life measured by EQ-5D-5L, and disability measured by the Roland Morris disability questionnaire. Cost measures include all relevant additional costs of the extended implementation strategy compared to usual implementation. The economic evaluation will be performed from both a societal perspective and a health sector perspective with a 12-month time horizon. It is expected that the extended implementation strategy will reduce the number of patients referred to secondary care. It is hypothesised that the additional upfront cost of extended implementation will be counterbalanced by improvements in clinical practice and patient-related outcomes, thereby rendering the extended implementation strategy cost-effective. ClinicalTrials.gov: NCT01699256.

Speech pathologists’ experiences with stroke clinical practice guidelines and the barriers and facilitators influencing their use: a national descriptive study

PubMed Central

2014-01-01

Background Communication and swallowing disorders are a common consequence of stroke. Clinical practice guidelines (CPGs) have been created to assist health professionals to put research evidence into clinical practice and can improve stroke care outcomes. However, CPGs are often not successfully implemented in clinical practice and research is needed to explore the factors that influence speech pathologists’ implementation of stroke CPGs. This study aimed to describe speech pathologists’ experiences and current use of guidelines, and to identify what factors influence speech pathologists’ implementation of stroke CPGs. Methods Speech pathologists working in stroke rehabilitation who had used a stroke CPG were invited to complete a 39-item online survey. Content analysis and descriptive and inferential statistics were used to analyse the data. Results 320 participants from all states and territories of Australia were surveyed. Almost all speech pathologists had used a stroke CPG and had found the guideline “somewhat useful” or “very useful”. Factors that speech pathologists perceived influenced CPG implementation included the: (a) guideline itself, (b) work environment, (c) aspects related to the speech pathologist themselves, (d) patient characteristics, and (e) types of implementation strategies provided. Conclusions There are many different factors that can influence speech pathologists’ implementation of CPGs. The factors that influenced the implementation of CPGs can be understood in terms of knowledge creation and implementation frameworks. Speech pathologists should continue to adapt the stroke CPG to their local work environment and evaluate their use. To enhance guideline implementation, they may benefit from a combination of educational meetings and resources, outreach visits, support from senior colleagues, and audit and feedback strategies. PMID:24602148

Adherence to, and outcomes of, a galactomannan screening protocol in high-risk hematology patients.

PubMed

Harricharan, S; Biederman, K; Bombassaro, A M; Lazo-Langner, A; Elsayed, S; Fulford, A; Delport, J A; Xenocostas, A

2018-04-01

A twice-weekly galactomannan (gm) screening protocol was implemented in high-risk hematology inpatients. Study objectives were to determine adherence to the protocol, use of selected resources, and patient outcomes. This retrospective cohort study compared outcomes of interest before and after implementation of gm screening. Adults undergoing matched related allogeneic hematopoietic stem-cell transplantation or induction chemotherapy for acute leukemia were eligible. Patients could be enrolled more than once and were evaluated as episodes. Adherence to the gm protocol was assessed in post-implementation episodes. Use of broad-spectrum antifungals (bsafs), consultations (infectious diseases, respirology), and diagnostic procedures (computed tomography imaging, bronchoalveolar lavage) were compared between phases, as were the patient outcomes of all-cause mortality and clinical success (alive and not taking a bsaf). Of 182 episodes consecutively screened, 70 per phase were enrolled. Clinical characteristics and duration of assessment were similar for the phases. Full or partial adherence to the protocol was observed in 61 post-implementation episodes (87%), with full adherence in 40 episodes (57%). More episodes in the pre-implementation phase than in the post-implementation phase involved receipt of bsafs, consultations, and diagnostics (27% vs. 7%, p = 0.02; 46% vs. 26%, p = 0.014; and 46% vs. 31%, p = 0.083 respectively). Although mortality was similar in the two phases, clinical success at the final assessment was observed in fewer pre-implementation than post-implementation episodes (79% vs. 98%, p < 0.001). Implementation of a gm screening protocol was feasible and associated with significantly fewer episodes involving receipt of bsafs and consultations, and with significantly more episodes showing clinical success.

The evidence-practice gap in specialist mental healthcare: systematic review and meta-analysis of guideline implementation studies.

PubMed

Girlanda, Francesca; Fiedler, Ines; Becker, Thomas; Barbui, Corrado; Koesters, Markus

2017-01-01

Clinical practice guidelines are not easily implemented, leading to a gap between research synthesis and their use in routine care. To summarise the evidence relating to the impact of guideline implementation on provider performance and patient outcomes in mental healthcare settings, and to explore the performance of different strategies for guideline implementation. A systematic review of randomised controlled trials, controlled clinical trials and before-and-after studies comparing guideline implementation strategies v. usual care, and different guideline implementation strategies, in patients with severe mental illness. In total, 19 studies met our inclusion criteria. The studies did not show a consistent positive effect of guideline implementation on provider performance, but a more consistent small to modest positive effect on patient outcomes. Guideline implementation does not seem to have an impact on provider performance, nonetheless it may influence patient outcomes positively. © The Royal College of Psychiatrists 2017.

Implementation of clinical decision rules in the emergency department.

PubMed

Stiell, Ian G; Bennett, Carol

2007-11-01

Clinical decision rules (CDRs) are tools designed to help clinicians make bedside diagnostic and therapeutic decisions. The development of a CDR involves three stages: derivation, validation, and implementation. Several criteria need to be considered when designing and evaluating the results of an implementation trial. In this article, the authors review the results of implementation studies evaluating the effect of four CDRs: the Ottawa Ankle Rules, the Ottawa Knee Rule, the Canadian C-Spine Rule, and the Canadian CT Head Rule. Four implementation studies demonstrated that the implementation of CDRs in the emergency department (ED) safely reduced the use of radiography for ankle, knee, and cervical spine injuries. However, a recent trial failed to demonstrate an impact on computed tomography imaging rates. Well-developed and validated CDRs can be successfully implemented into practice, efficiently standardizing ED care. However, further research is needed to identify barriers to implementation in order to achieve improved uptake in the ED.

Establishment, Implementation, and Consolidation of Clinical Pharmacy Services in Community Pharmacies: Perceptions of a Group of Pharmacists.

PubMed

Dosea, Aline S; Brito, Giselle C; Santos, Lincoln M C; Marques, Tatiane C; Balisa-Rocha, Blície; Pimentel, Deborah; Bueno, Denise; Lyra, Divaldo P

2017-02-01

When pharmacists incorporate clinical practice into their routine, barriers and facilitators influence the implementation of patient care services. Three focus groups were conducted with 11 pharmacists who were working for the Farmácia Popular do Brasil program on the establishment, implementation, and consolidation of clinical pharmacy services. The perception of the pharmacists in Brazil about the program was that it facilitated access to health care and medication. The distance between neighboring cities made it difficult for patients to return for services. Lack of staff training created a lack of communication skills and knowledge. The pharmacists wanted to have increased technical support, skill development opportunities, and monitoring of researchers who assessed progress of the service. Pharmacists overcame many of their insecurities and felt more proactive and committed to quality service. Positive experiences in service implementations have shown that it is possible to develop a model of clinical services in community pharmacies.

Everybody wants it done but nobody wants to do it: an exploration of the barrier and enablers of critical components towards creating a clinical pathway for anxiety and depression in cancer.

PubMed

Rankin, Nicole M; Butow, Phyllis N; Thein, Thida; Robinson, Tracy; Shaw, Joanne M; Price, Melanie A; Clover, Kerrie; Shaw, Tim; Grimison, Peter

2015-01-22

This study aimed to explore barriers to and enablers for future implementation of a draft clinical pathway for anxiety and depression in cancer patients in the Australian context. Health professionals reviewed a draft clinical pathway and participated in qualitative interviews about the delivery of psychosocial care in their setting, individual components of the draft pathway, and barriers and enablers for its future implementation. Five interrelated themes were identified: ownership; resources and responsibility; education and training; patient reluctance; and integration with health services beyond oncology. The five themes were perceived as both barriers and enablers and provide a basis for an implementation plan that includes strategies to overcome barriers. The next steps are to design and deliver the clinical pathway with specific implementation strategies that address team ownership, endorsement by leaders, education and training modules designed for health professionals and patients and identify ways to integrate the pathway into existing cancer services.

Barriers to ESC guideline implementation: results of a survey from the European Council on Cardiovascular Nursing and Allied Professions (CCNAP).

PubMed

McKee, Gabrielle; Kerins, Mary; Hamilton, Glenys; Hansen, Tina; Hendriks, Jeroen; Kletsiou, Eleni; Lambrinou, Ekaterini; Jennings, Catriona; Fitzsimons, Donna

2017-12-01

The European Society of Cardiology (ESC) has a comprehensive clinical guideline development programme, relevant for all clinicians. However, implementation of guidelines is not always optimal. The aim of this study was to determine nurses' and allied professionals' awareness and barriers regarding clinical guideline implementation. A cross-sectional survey was administrated online and in print at EuroHeartCare 2015. A questionnaire was developed which examined awareness and barriers to implementation of ESC guidelines on cardiovascular disease prevention in clinical practice (2012) and ESC guidelines in general. Of the 298 respondents, 12% reported that the prevention guidelines were used in their practice area. Respondents identified, in order of magnitude, that lack of leadership, workload, time, resources and a perception that they were unable to influence current practice were barriers to the use of the prevention guidelines. When asked to rank barriers to use of any ESC guidelines, time (22%) and leadership (23%) were ranked highest. Implementation of ESC guidelines by nurses, the majority responders in this survey, is a serious problem, requiring urgent improvement to ensure patients receive optimal evidence based care. Issues of leadership, workload, time and resources are significant barriers to guideline implementation. It is of concern that these professionals perceive both that they have little influence on implementation decisions and lack of leadership regarding guideline implementation. Educational and organisational strategies to improve leadership skills are imperative. These will build self-efficacy and empower nurses and allied professionals to advocate for evidence-based care in the clinical environment.

Evaluation of a TB infection control implementation initiative in out-patient HIV clinics in Zambia and Botswana.

PubMed

Emerson, C; Lipke, V; Kapata, N; Mwananyambe, N; Mwinga, A; Garekwe, M; Lanje, S; Moshe, Y; Pals, S L; Nakashima, A K; Miller, B

2016-07-01

Out-patient human immunodeficiency virus (HIV) care and treatment clinics in Zambia and Botswana, countries with a high burden of HIV and TB infection. To develop a tuberculosis infection control (TB IC) training and implementation package and evaluate the implementation of TB IC activities in facilities implementing the package. Prospective program evaluation of a TB IC training and implementation package using a standardized facility risk assessment tool, qualitative interviews with facility health care workers and measures of pre- and post-test performance. A composite measure of facility performance in TB IC improved from 32% at baseline to 50% at 1 year among eight facilities in Zambia, and from 27% to 80% at 6 months among 10 facilities in Botswana. Although there was marked improvement in indicators of managerial, administrative and environmental controls, key ongoing challenges remained in ensuring access to personal protective equipment and implementing TB screening in health care workers. TB IC activities at out-patient HIV clinics in Zambia and Botswana improved after training using the implementation package. Continued infrastructure support, as well as monitoring and evaluation, are needed to support the scale-up and sustainability of TB IC programs in facilities in low-resource countries.

Designing and implementing a skills program Using a clinically integrated, multi-professional approach: Using evaluation to drive curriculum change

PubMed Central

Carr, Sandra E.; Celenza, Antonio; Lake, Fiona

2009-01-01

The essential procedural skills that newly graduated doctors require are rarely defined, do not take into account pre-vocational employer expectations, and differ between Universities. This paper describes how one Faculty used local evaluation data to drive curriculum change and implement a clinically integrated, multi-professional skills program. A curriculum restructure included a review of all undergraduate procedural skills training by academic staff and clinical departments, resulting in a curriculum skills map. Undergraduate training was then linked with postgraduate expectations using the Delphi process to identify the skills requiring structured standardised training. The skills program was designed and implemented without a dedicated simulation center. This paper shows the benefits of an alternate model in which clinical integration of training and multi-professional collaboration encouraged broad ownership of a program and, in turn, impacted the clinical experience obtained. PMID:20165528

Strategies For Clinical Implementation: Precision Oncology At Three Distinct Institutions.

PubMed

Nadauld, Lincoln D; Ford, James M; Pritchard, Daryl; Brown, Thomas

2018-05-01

Despite rapid advances in molecular diagnostics and targeted therapeutics, the adoption of precision medicine into clinical oncology workflows has been slow. Questions about clinical utility, inconsistent reimbursement for molecular diagnostics, and limited access to targeted therapies are some of the major hurdles that have hampered clinical adoption. Despite these challenges, providers have invested in precision medicine programs in an ongoing search for innovative care models to deliver improved patient outcomes and achieve economic gains. We describe the precision oncology medicine programs implemented by an integrated delivery system, a community care center, and an academic medical center, to demonstrate the approaches and challenges associated with clinical implementation efforts designed to advance this treatment paradigm. Payer policies that include coverage for broad genomic testing panels would support the broader application of precision medicine, deepen research benefits, and bring targeted therapies to more patients with advanced cancer.

A tracking and verification system implemented in a clinical environment for partial HIPAA compliance

NASA Astrophysics Data System (ADS)

Guo, Bing; Documet, Jorge; Liu, Brent; King, Nelson; Shrestha, Rasu; Wang, Kevin; Huang, H. K.; Grant, Edward G.

2006-03-01

The paper describes the methodology for the clinical design and implementation of a Location Tracking and Verification System (LTVS) that has distinct benefits for the Imaging Department at the Healthcare Consultation Center II (HCCII), an outpatient imaging facility located on the USC Health Science Campus. A novel system for tracking and verification of patients and staff in a clinical environment using wireless and facial biometric technology to monitor and automatically identify patients and staff was developed in order to streamline patient workflow, protect against erroneous examinations and create a security zone to prevent and audit unauthorized access to patient healthcare data under the HIPAA mandate. This paper describes the system design and integration methodology based on initial clinical workflow studies within a clinical environment. An outpatient center was chosen as an initial first step for the development and implementation of this system.

[Real-time PCR detection of Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae DNA in clinical specimens].

PubMed

Vacková, Z; Lžičařová, D; Stock, N K; Kozáková, J

2015-10-01

The study aim was to implement a molecular real-time polymerase chain reaction (PCR) assay recommended by the CDC (Centers for Disease Control and Prevention) for the detection of Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae in clinical (culture negative) specimens from patients with suspected invasive bacterial disease. Clinical specimens are referred to the National Reference Laboratory (NRL) for Meningococcal Infections, Unit for Airborne Bacterial Infections, Centre for Epidemiology and Microbiology, National Institute of Public Health from various regions of the Czech Republic. Clinical specimens are, in particular, cerebrospinal fluid, anti-coagulated blood or serum and, exceptionally, post-mortem specimens. The NRL has implemented molecular diagnosis of these bacterial pathogens involved in meningitis and sepsis from clinical specimens since 1999. The first diagnostic method was semi-nested PCR followed by electrophoretic analysis. In 2014, a molecular qualitative real-time PCR assay was implemented.

Development and implementation of a navigator-facilitated care coordination algorithm to improve clinical outcomes of underserved Latino patients with uncontrolled diabetes.

PubMed

Congdon, Heather Brennan; Eldridge, Barbara Hoffman; Truong, Hoai-An

2013-11-01

Development and implementation of an interprofessional navigator-facilitated care coordination algorithm (NAVCOM) for low-income, uninsured patients with uncontrolled diabetes at a safety-net clinic resulted in improvement of disease control as evidenced by improvement in hemoglobin A1C. This report describes the process and lessons learned from the development and implementation of NAVCOM and patient success stories.

An implementation-focused process evaluation of an incentive intervention effectiveness trial in substance use disorders clinics at two Veterans Health Administration medical centers.

PubMed

Hagedorn, Hildi J; Stetler, Cheryl B; Bangerter, Ann; Noorbaloochi, Siamak; Stitzer, Maxine L; Kivlahan, Daniel

2014-07-09

One of the pressing concerns in health care today is the slow rate at which promising interventions, supported by research evidence, move into clinical practice. One potential way to speed this process is to conduct hybrid studies that simultaneously combine the collection of effectiveness and implementation relevant data. This paper presents implementation relevant data collected during a randomized effectiveness trial of an abstinence incentive intervention conducted in substance use disorders treatment clinics at two Veterans Health Administration (VHA) medical centers. Participants included patients entering substance use disorders treatment with diagnoses of alcohol dependence and/or stimulant dependence that enrolled in the randomized trial, were assigned to the intervention arm, and completed a post intervention survey (n = 147). All staff and leadership from the participating clinics were eligible to participate. A descriptive process evaluation was used, focused on participant perceptions and contextual/feasibility issues. Data collection was guided by the RE-AIM and PARIHS implementation frameworks. Data collection methods included chart review, intervention cost tracking, patient and staff surveys, and qualitative interviews with staff and administrators. Results indicated that patients, staff and administrators held generally positive attitudes toward the incentive intervention. However, staff and administrators identified substantial barriers to routine implementation. Despite the documented low cost and modest staff time required for implementation of the intervention, securing funding for the incentives and freeing up any staff time for intervention administration were identified as primary barriers. Recommendations to facilitate implementation are presented. Recommendations include: 1) solicit explicit support from the highest levels of the organization through, for example, performance measures or clinical practice guideline recommendations; 2) adopt the intervention incrementally starting within a specific treatment track or clinic to reduce staff and funding burden until local evidence of effectiveness and feasibility is available to support spread; and 3) educate staff about the process, goals, and value/effectiveness of the intervention and engage them in implementation planning from the start to enhance investment in the intervention.

Translational Radiomics: Defining the Strategy Pipeline and Considerations for Application-Part 2: From Clinical Implementation to Enterprise.

PubMed

Shaikh, Faiq; Franc, Benjamin; Allen, Erastus; Sala, Evis; Awan, Omer; Hendrata, Kenneth; Halabi, Safwan; Mohiuddin, Sohaib; Malik, Sana; Hadley, Dexter; Shrestha, Rasu

2018-03-01

Enterprise imaging has channeled various technological innovations to the field of clinical radiology, ranging from advanced imaging equipment and postacquisition iterative reconstruction tools to image analysis and computer-aided detection tools. More recently, the advancement in the field of quantitative image analysis coupled with machine learning-based data analytics, classification, and integration has ushered in the era of radiomics, a paradigm shift that holds tremendous potential in clinical decision support as well as drug discovery. However, there are important issues to consider to incorporate radiomics into a clinically applicable system and a commercially viable solution. In this two-part series, we offer insights into the development of the translational pipeline for radiomics from methodology to clinical implementation (Part 1) and from that point to enterprise development (Part 2). In Part 2 of this two-part series, we study the components of the strategy pipeline, from clinical implementation to building enterprise solutions. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

[Evidence based practice of nurses working in university hospitals in the French speaking part of Switzerland: a descriptive and correlational study

PubMed

Gentizon, Jenny; Borrero, Patricia; Vincent-Suter, Sonja; Ballabeni, Pierluigi; Morin, Diane; Eicher, Manuela

2016-12-01

Introduction : evidence-based practice (EBP) is too scarcely applied in nursing and is a key contemporary challenge for the discipline. Method and objective : This descriptive and correlational study invited 221 nurses working in three different clinical settings of university hospitals in Switzerland. The objective of this study was to describe their level of knowledge, beliefs and implementation of EBP. Results : of the 221 nurses in this study, only 67 were familiar EBP (30%). These demonstrate favorable beliefs and attitudes towards EBP, but indicate a lack of skills and knowledge to implement it. Compared to both internal medicine and geriatric nurses clinical nurse specialists (ISC) were significantly more familiar with EBP and its implementation. Results also indicate that positive nurses’ beliefs and attitudes toward EBP are predictive of better implementation in clinical practice. Discussion and Conclusion : as demonstrated in other studies, our results show that knowledge about EBP is not that widespread and its implementation remains a challenge even in university hospitals. Future work could include testing EBP implementation strategies to overcome the barriers identified.

How to implement a clinical pathway for intensive glucose regulation in acute coronary syndromes.

PubMed

de Mulder, Maarten; Zwaan, Esther; Wielinga, Yvonne; Stam, Frank; Umans, Victor A W M

2009-06-01

Hyperglycemia upon admission of myocardial infarction patients predicts inferior clinical outcomes. Current strategies investigating hyperglycemia correction mostly use glucose-driven protocols. Implementation of these often labor-intensive protocols might be facilitated with the approach of a clinical pathway. Therefore, we evaluated the implementation of our glucose-driven protocol.We adapted a protocol for use in our coronary care unit (CCU), which was implemented according to the steps of a clinical pathway. To compensate for carbohydrates in meals we additionally developed a regimen of subcutaneous insulin.Protocol adherence was facilitated with a Web-based insulin calculator. All hyperglycemic patients admitted to the CCU were eligible for treatment according to this protocol.In a 4-month period, 643 glucose measurements were obtained in hyperglycemic patients admitted to our CCU. Patients were treated intensively with IV insulin for 35 hours and had 23 glucose measurements in this time span on average. This regimen achieved a median glucose of 6.2 mmol/L. Severe hypoglycemia occurred in only 1.1% of measurements and was without severe clinical side effects.Introduction of new intensive insulin protocol according to the steps of a clinical pathway is safe and feasible. The presence of a clinical pathway coordinator and sound communication are important conditions for successful introduction, which can be further aided with a computerized calculator.

Change management and clinical engagement: critical elements for a successful clinical information system implementation.

PubMed

Detwiller, Maureen; Petillion, Wendy

2014-06-01

Moving a large healthcare organization from an old, nonstandardized clinical information system to a new user-friendly, standards-based system was much more than an upgrade to technology. This project to standardize terminology, optimize key processes, and implement a new clinical information system was a large change initiative over 4 years that affected clinicians across the organization. Effective change management and engagement of clinical stakeholders were critical to the success of the initiative. The focus of this article was to outline the strategies and methodologies used and the lessons learned.

Framework for a clinical information system.

PubMed

Van De Velde, R; Lansiers, R; Antonissen, G

2002-01-01

The design and implementation of Clinical Information System architecture is presented. This architecture has been developed and implemented based on components following a strong underlying conceptual and technological model. Common Object Request Broker and n-tier technology featuring centralised and departmental clinical information systems as the back-end store for all clinical data are used. Servers located in the "middle" tier apply the clinical (business) model and application rules. The main characteristics are the focus on modelling and reuse of both data and business logic. Scalability as well as adaptability to constantly changing requirements via component driven computing are the main reasons for that approach.

Implementation Considerations for Multisite Clinical Trials with Cognitive Neuroscience Tasks

PubMed Central

Keefe, Richard S. E.; Harvey, Philip D.

2008-01-01

Multisite clinical trials aimed at cognitive enhancement across various neuropsychiatric conditions have employed standard neuropsychological tests as outcome measures. While these tests have enjoyed wide clinical use and have proven reliable and predictive of functional disability, a number of implementation challenges have arisen when these tests are used in clinical trials. These issues are likely to be magnified in future studies when cognitive neuroscience (CN) procedures are explored in these trials, because in their current forms CN procedures are less standardized and more difficult to teach and monitor. For multisite trials, we anticipate that the most challenging issues will include assuring tester competence, monitoring tester performance, specific challenges with complex assessment methods, and having resources available for adequate monitoring of data quality. Suggestions for overcoming these implementation challenges are offered. PMID:18495645

Using the diffusion of innovations theory to assess socio-technical factors in planning the implementation of an electronic health record alert across multiple primary care clinics.

PubMed

Lin, Ching-Pin; Guirguis-Blake, Janelle; Keppel, Gina A; Dobie, Sharon; Osborn, Justin; Cole, Allison M; Baldwin, Laura-Mae

2016-04-15

Adverse drug events (ADEs) are a leading cause of death in the United States. Patients with stage 3 and 4 chronic kidney disease (CKD) are at particular risk because many medications are cleared by the kidneys. Alerts in the electronic health record (EHR) about drug appropriateness and dosing at the time of prescription have been shown to reduce ADEs for patients with stage 3 and 4 CKD in inpatient settings, but more research is needed about the implementation and effectiveness of such alerts in outpatient settings.  To explore factors that might inform the implementation of an electronic drug-disease alert for patients with CKD in primary care clinics, using Rogers' diffusion of innovations theory as an analytic framework. Interviews were conducted with key informants in four diverse clinics using various EHR systems. Interviews were audio recorded and transcribed. results Although all clinics had a current method for calculating glomerular filtration rate (GFR), clinics were heterogeneous with regard to current electronic decision support practices, quality improvement resources, and organizational culture and structure. Understanding variation in organizational culture and infrastructure across primary care clinics is important in planning implementation of an intervention to reduce ADEs among patients with CKD.

Operational Transition from the First-Generation Heidelberg Spectralis Optical Coherence Tomography [OCT("OCT1")] to the Second-Generation Heidelberg Spectralis OCT("OCT2")

NASA Technical Reports Server (NTRS)

Mason, S.; Brunstetter, T.; Young, M.; Van Baalen, M.; Tarver, W.; Derrick, R.; Wells, J.; Dey, B.; Todd, K.; Smith, B.;