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Sample records for accurate preoperative planning

  1. The value of preoperative planning.

    PubMed

    Graves, Matt L

    2013-10-01

    "Better to throw your disasters into the waste paper basket than to consign your patients to the scrap heap" has been a proverb of Jeff Mast, one of the greatest fracture and deformity surgeons in the history of our specialty. Stated slightly more scientifically, one of the major values of simulation is that it allows one to make mistakes in a consequence-free environment. Preoperative planning is the focus of this article. The primary goal is not to provide you with a recipe of how to steps. Rather, the primary goal of this article is to explain why preoperative planning should be standard, to clarify what should be included, and to provide examples of what can happen when planning is ignored. At the end of this, we should all feel the need to approach fracture care more intellectually with forethought, both in our own practices and in our educational system. PMID:23880563

  2. Computed Tomography Angiography for Preoperative Thoracoabdominal Flap Planning.

    PubMed

    O'Malley, Ryan B; Robinson, Tracy J; Kozlow, Jeffrey H; Liu, Peter S

    2016-01-01

    Mastectomy rates have increased, coinciding with more advanced reconstruction options. Deep inferior epigastric perforator (DIEP) flaps decrease abdominal donor site morbidity, but require considerable technical expertise. Preoperative computed tomography angiography (CTA) can accurately demonstrate DIEA anatomy and perforator courses, facilitating preoperative planning and flap design, allowing for more targeted intraoperative microdissection. Patients who undergo CTA before DIEP flap have better clinical outcomes with shorter operative times and hospital length of stay, which can decrease overall associated health care costs. Future directions include selected imaging of the thoracic anatomy and recipient vasculature, allowing for additional preoperative planning and customization. PMID:26654396

  3. Preoperative Planning of Orthopedic Procedures using Digitalized Software Systems.

    PubMed

    Steinberg, Ely L; Segev, Eitan; Drexler, Michael; Ben-Tov, Tomer; Nimrod, Snir

    2016-06-01

    The progression from standard celluloid films to digitalized technology led to the development of new software programs to fulfill the needs of preoperative planning. We describe here preoperative digitalized programs and the variety of conditions for which those programs can be used to facilitate preparation for surgery. A PubMed search using the keywords "digitalized software programs," "preoperative planning" and "total joint arthroplasty" was performed for all studies regarding preoperative planning of orthopedic procedures that were published from 1989 to 2014 in English. Digitalized software programs are enabled to import and export all picture archiving communication system (PACS) files (i.e., X-rays, computerized tomograms, magnetic resonance images) from either the local working station or from any remote PACS. Two-dimension (2D) and 3D CT scans were found to be reliable tools with a high preoperative predicting accuracy for implants. The short learning curve, user-friendly features, accurate prediction of implant size, decreased implant stocks and low-cost maintenance makes digitalized software programs an attractive tool in preoperative planning of total joint replacement, fracture fixation, limb deformity repair and pediatric skeletal disorders. PMID:27468530

  4. A computerized morphometric evaluation of x-ray films for preoperative planning of hip arthroplasty.

    PubMed

    Baruffaldi, F; Cianci, R; Fabbri, F; Mulazzani, M; Fanton, F; Toni, A; Affatato, S; Giunti, A

    1994-01-01

    Methods for measuring metric size on radiograms constitute an instrument of proven utility. For example, when preoperatively evaluating hip arthroplasty the diameter of the medullary canal and the cervicodiaphyseal angle, must be measured in order to determine the center of rotation of the femoral head, and to establish the flare index of the diaphyseal canal. These results may be obtained by using a computer-controlled graphic table to place the coordinates for the areas of greater anatomical and physiological importance on the radiologic image. Thus, a calculation of distances, anatomical axes and angles is obtained immediately, accurately defining the morphometry of the joint. In this study, the anteroposterior preoperative radiographic views of 87 femurs in 84 patients were evaluated by this method. The values provided by the morphometric analysis were then related to sex, age and weight. The diaphyseal canal was classified by typology for the preoperative planning of hip arthroplasty. PMID:7842840

  5. Liver surgery perspective: from pre-operative surgery planning to intra-operative image guided operation

    NASA Astrophysics Data System (ADS)

    Li, Senhu; Lennon, Brian T.; Waite, Jon M.; Clements, Logan W.; Scherer, Mike A.; Stefansic, Jim D.

    2009-10-01

    Liver cancer represents a major health care problem in the world, especially in China and several countries in Southeast Asia. The most effective treatment is through tumor resection. To improve the outcome of surgery, a combination of preoperative planning and intra operative image guided liver surgery (IGLS) system has been developed at Pathfinder Therapeutics, Inc. The preoperative planning subsystem (Linasys® PlaniSight®) is user-oriented and applies several novel algorithms on image segmentation and modeling, which allows the user to build various organ and tumor models with anticipated resection planes in less than 30 minutes. The surgeons can analyze the patient-specific case and set up surgical protocols. This information in image space can then be transferred into physical space through our intra operative image guided liver surgery system (Linasys® SurgSight®) based on modifications of existing surface registration algorithms, allowing surgeons to perform more accurate resections after preoperative planning. This tool gives surgeons a better understanding of vessel structure and tumor locations within the liver parenchyma during the surgery. Our ongoing clinical trial shows that it greatly facilitates liver resection operation and it is expected to improve the surgery outcome and create more candidates for surgery.

  6. New law requires 'medically accurate' lesson plans.

    PubMed

    1999-09-17

    The California Legislature has passed a bill requiring all textbooks and materials used to teach about AIDS be medically accurate and objective. Statements made within the curriculum must be supported by research conducted in compliance with scientific methods, and published in peer-reviewed journals. Some of the current lesson plans were found to contain scientifically unsupported and biased information. In addition, the bill requires material to be "free of racial, ethnic, or gender biases." The legislation is supported by a wide range of interests, but opposed by the California Right to Life Education Fund, because they believe it discredits abstinence-only material. PMID:11366835

  7. Preoperative assessment and planning of haemodialysis vascular access.

    PubMed

    Lomonte, Carlo; Basile, Carlo

    2015-06-01

    Effective haemodialysis (HD) requires a reliable vascular access (VA). Clinical practice guidelines strongly recommend the arteriovenous fistula (AVF) as the preferred VA in HD patients. The creation of an AVF should be promoted in all eligible patients who choose HD, as it improves outcomes and reduces costs when compared with central venous catheters. Fistula eligibility is a 'work in progress'. Three steps in order to increase the pool of eligible patients can be individualized: (i) process of care, which includes three fundamental items: the VA team, early VA education and timely VA surgery referral; (ii) preoperative evaluation; (iii) surgical strategy. Nephrologists should be able to play a leading and coordinating role of the VA team. They should design a plan that identifies a sequence of options that can be used to provide adequate renal replacement therapy throughout the life span of every end-stage renal disease patient. The main points of this strategy are (i) early vascular education, in which a 'save the vein program' should always be implemented; (ii) timely VA surgery referral and preoperative evaluation: careful examination of arterial and venous beds is mandatory before VA placement; physical examination in addition to colour Doppler ultrasound mapping improves AVF outcomes; (iii) surgical strategy: a successful VA strategy must take into account vascular anatomy, clinical factors and prognosis. PMID:26034588

  8. C-018H Pre-Operational Baseline Sampling Plan

    SciTech Connect

    Guzek, S.J.

    1993-08-20

    The objective of this task is to field characterize and sample the soil at selected locations along the proposed effluent line routes for Project C-018H. The overall purpose of this effort is to meet the proposed plan to discontinue the disposal of contaminated liquids into the Hanford soil column as described by DOE (1987). Detailed information describing proposed transport pipeline route and associated Kaiser Engineers Hanford Company (KEH) preliminary drawings (H288746...755) all inclusive, have been prepared by KEH (1992). The information developed from field monitoring and sampling will be utilized to characterize surface and subsurface soil along the proposed C-018H effluent pipeline and it`s associated facilities. Potentially existing contaminant levels may be encountered therefore, soil characterization will provide a construction preoperational baseline reference, develop personnel safety requirements, and determine the need for any changes in the proposed routes prior to construction of the pipeline.

  9. Target motion predictions for pre-operative planning during needle-based interventions.

    PubMed

    op den Buijs, Jorn; Abayazid, Momen; de Korte, Chris L; Misra, Sarthak

    2011-01-01

    During biopsies, breast tissue is subjected to displacement upon needle indentation, puncture, and penetration. Thus, accurate needle placement requires pre-operative predictions of the target motions. In this paper, we used ultrasound elastography measurements to non-invasively predict elastic properties of breast tissue phantoms. These properties were used in finite element (FE) models of indentation of breast soft tissue phantoms. To validate the model predictions of target motion, experimental measurements were carried out. Breast tissue phantoms with cubic and hemispherical geometries were manufactured and included materials with different elastic properties to represent skin, adipose tissue, and lesions. Ultrasound was used to track the displacement of the target (i.e., the simulated lesion) during indentation. The FE model predictions were compared with ultrasound measurements for cases with different boundary conditions and phantom geometry. Maximum errors between measured and predicted target motions were 12% and 3% for the fully supported and partially supported cubic phantoms at 6.0 mm indentation, respectively. Further, FE-based parameter sensitivity analysis indicated that increasing skin elastic modulus and reducing the target depth location increased the target motion. Our results indicate that with a priori knowledge about the geometry, boundary conditions, and linear elastic properties, indentation of breast tissue phantoms can be accurately predicted with FE models. FE models for pre-operative planning in combination with robotic needle insertions, could play a key role in improving lesion targeting for breast biopsies. PMID:22255554

  10. Physics-based simulation of surgical fields for preoperative strategic planning.

    PubMed

    Nakao, Megumi; Kuroda, Tomohiro; Oyama, Hiroshi; Sakaguchi, Genichi; Komeda, Masashi

    2006-10-01

    Although careful planning of surgical approach is a key for success of surgery, conventional planning and simulation tools cannot support detailed discussion. This issue is derived from the difficulty of estimating complex physical behavior of soft tissues provided by a series of surgical procedures like cutting and deformation. This paper proposes an adaptive physics-based framework that simulates both interactive cutting and accurate deformation on virtual bodies, and performs preoperative planning for supporting strategic discussion. We focus on limited use of the two models: A particle-based model and an FEM-based model considering required quality and performance in different situations. FEM-based deformation of incision accurately produces estimated surgical fields. Based on the framework, a strategic planning system was developed for supporting decision of surgical approach using 3D representation of the surgical fields. We applied clinical CT dataset of an aortic aneurysm case to the system. Some experiments and usability tests confirmed that the system contributes to grasping 3D shape and location of the target organs and performs detailed discussion on patient-specific surgical approaches. PMID:17069000

  11. The need for preoperative baseline arm measurement to accurately quantify breast cancer-related lymphedema.

    PubMed

    Sun, Fangdi; Skolny, Melissa N; Swaroop, Meyha N; Rawal, Bhupendra; Catalano, Paul J; Brunelle, Cheryl L; Miller, Cynthia L; Taghian, Alphonse G

    2016-06-01

    Breast cancer-related lymphedema (BCRL) is a feared outcome of breast cancer treatment, yet the push for early screening is hampered by a lack of standardized quantification. We sought to determine the necessity of preoperative baseline in accounting for temporal changes of upper extremity volume. 1028 women with unilateral breast cancer were prospectively screened for lymphedema by perometry. Thresholds were defined: relative volume change (RVC) ≥10 % for clinically significant lymphedema and ≥5 % including subclinical lymphedema. The first postoperative measurement (pseudo-baseline) simulated the case of no baseline. McNemar's test and binomial logistic regression models were used to analyze BCRL misdiagnoses. Preoperatively, 28.3 and 2.9 % of patients had arm asymmetry of ≥5 and 10 %, respectively. Without baseline, 41.6 % of patients were underdiagnosed and 40.1 % overdiagnosed at RVC ≥ 5 %, increasing to 50.0 and 54.8 % at RVC ≥ 10 %. Increased pseudo-baseline asymmetry, increased weight change between baselines, hormonal therapy, dominant use of contralateral arm, and not receiving axillary lymph node dissection (ALND) were associated with increased risk of underdiagnosis at RVC ≥ 5 %; not receiving regional lymph node radiation was significant at RVC ≥ 10 %. Increased pseudo-baseline asymmetry, not receiving ALND, and dominant use of ipsilateral arm were associated with overdiagnosis at RVC ≥ 5 %; increased pseudo-baseline asymmetry and not receiving ALND were significant at RVC ≥ 10 %. The use of a postoperative proxy even early after treatment results in poor sensitivity for identifying BCRL. Providers with access to patients before surgery should consider the consequent need for proper baseline, with specific strategy tailored by institution. PMID:27154787

  12. Preoperative treatment planning with intraoperative optimization can achieve consistent high-quality implants in prostate brachytherapy

    SciTech Connect

    Kudchadker, Rajat J.; Pugh, Thomas J.; Swanson, David A.; Bruno, Teresa L.; Bolukbasi, Yasemin; Frank, Steven J.

    2012-01-01

    Advances in brachytherapy treatment planning systems have allowed the opportunity for brachytherapy to be planned intraoperatively as well as preoperatively. The relative advantages and disadvantages of each approach have been the subject of extensive debate, and some contend that the intraoperative approach is vital to the delivery of optimal therapy. The purpose of this study was to determine whether high-quality permanent prostate implants can be achieved consistently using a preoperative planning approach that allows for, but does not necessitate, intraoperative optimization. To achieve this purpose, we reviewed the records of 100 men with intermediate-risk prostate cancer who had been prospectively treated with brachytherapy monotherapy between 2006 and 2009 at our institution. All patients were treated with iodine-125 stranded seeds; the planned target dose was 145 Gy. Only 8 patients required adjustments to the plan on the basis of intraoperative findings. Consistency and quality were assessed by calculating the correlation coefficient between the planned and implanted amounts of radioactivity and by examining the mean values of the dosimetric parameters obtained on preoperative and 30 days postoperative treatment planning. The amount of radioactivity implanted was essentially identical to that planned (mean planned radioactivity, 41.27 U vs. mean delivered radioactivity, 41.36 U; R{sup 2} = 0.99). The mean planned and day 30 prostate V100 values were 99.9% and 98.6%, respectively. The mean planned and day 30 prostate D90 values were 186.3 and 185.1 Gy, respectively. Consistent, high-quality prostate brachytherapy treatment plans can be achieved using a preoperative planning approach, mostly without the need for intraoperative optimization. Good quality assurance measures during simulation, treatment planning, implantation, and postimplant evaluation are paramount for achieving a high level of quality and consistency.

  13. Preoperative planning of primary total hip arthroplasty using conventional radiographs☆☆☆

    PubMed Central

    Miashiro, Edson Hidenori; Fujiki, Edson Noboru; Yamaguchi, Eduardo Nagashigue; Chikude, Takeshi; Rodrigues, Luiz Henrique Silveira; Fontes, Gustavo Martins; Rosa, Fausto Boccatto

    2014-01-01

    Objective the objective of this study was to present an analog method for preoperative planning of primary total hip arthroplasty procedures based on measuring the components by overlaying the transparencies of the prosthesis on the preoperative radiographs and checking the accuracy, both for predicting the size of the acetabular and femoral components used and for restoring the offset and correcting the dysmetria. Methods between March 2005 and July 2009, 56 primary total hip arthroplasty procedures performed on 56 patients at the Mario Covas State Hospital in Santo André were analyzed. The measurements on the femoral and acetabular components obtained through planning were compared with those that were used in the surgery. The offsets measured through the preoperative planning were compared with those measured on the postoperative radiographs. Dysmetria was evaluated before and after the operation. Results accuracy of 78.6% (p < 0.001) in predicting the size of the acetabular component and 82.2% (p < 0.001) in predicting the femoral nail was observed. The offsets measured through preoperative planning were statistically similar to the offsets measured on the postoperative radiographs. After the operation, we observed absolute equalization in 48.2% of the cases. In 87.5%, the dysmetria was less than or equal to 1 cm and in 69.6%, it was less than or equal to 0.5 cm. Conclusions the accuracy was 78.6% and 82.2%, respectively, for the acetabular and femoral components. The offsets that were planned preoperatively were statistically similar to those measured on postoperative radiographs. We found absolute equalization in 48.2% of the cases. PMID:26229790

  14. Computer assisted 3D pre-operative planning tool for femur fracture orthopedic surgery

    NASA Astrophysics Data System (ADS)

    Gamage, Pavan; Xie, Sheng Quan; Delmas, Patrice; Xu, Wei Liang

    2010-02-01

    Femur shaft fractures are caused by high impact injuries and can affect gait functionality if not treated correctly. Until recently, the pre-operative planning for femur fractures has relied on two-dimensional (2D) radiographs, light boxes, tracing paper, and transparent bone templates. The recent availability of digital radiographic equipment has to some extent improved the workflow for preoperative planning. Nevertheless, imaging is still in 2D X-rays and planning/simulation tools to support fragment manipulation and implant selection are still not available. Direct three-dimensional (3D) imaging modalities such as Computed Tomography (CT) are also still restricted to a minority of complex orthopedic procedures. This paper proposes a software tool which allows orthopedic surgeons to visualize, diagnose, plan and simulate femur shaft fracture reduction procedures in 3D. The tool utilizes frontal and lateral 2D radiographs to model the fracture surface, separate a generic bone into the two fractured fragments, identify the pose of each fragment, and automatically customize the shape of the bone. The use of 3D imaging allows full spatial inspection of the fracture providing different views through the manipulation of the interactively reconstructed 3D model, and ultimately better pre-operative planning.

  15. Fusion of intraoperative cortical images with preoperative models for neurosurgical planning and guidance

    NASA Astrophysics Data System (ADS)

    Wang, An; Mirsattari, Seyed M.; Parrent, Andrew G.; Peters, Terry M.

    2009-02-01

    During surgery for epilepsy it is important for the surgeon to correlate the preoperative cortical morphology (from preoperative images) with the intraoperative environment. We extend our visualization method presented earlier, to achieves this goal by fusing a direct (photographic) view of the surgical field with the 3D patient model. To correlate the preoperative plan with the intraoperative surgical scene, an intensity-based perspective 3D-2D registration was employed for camera pose estimation. The 2D photographic image was then texture-mapped onto the 3D preoperative model using the solved camera pose. In the proposed method, we employ direct volume rendering to obtain a perspective view of the brain image using GPU-accelerated ray-casting. This is advantageous compared to the point-based or other feature-based registration since no intermediate processing is required. To validate our registration algorithm, we used a point-based 3D-2D registration, that was validated using ground truth from simulated data, and then the intensity-based 3D-2D registration method was validated using the point-based registration result as the gold standard. The registration error of the intensity-based 3D- 2D method was around 3mm when the initial pose is close to the gold standard. Application of the proposed method for correlating fMRI maps with intraoperative cortical stimulation is shown for surgical planning in an epilepsy patient.

  16. Preoperative implant planning considering alveolar bone grafting needs and complication prediction using panoramic versus CBCT images

    PubMed Central

    Guerrero, Maria Eugenia; Noriega, Jorge

    2014-01-01

    Purpose This study was performed to determine the efficacy of observers' prediction for the need of bone grafting and presence of perioperative complications on the basis of cone-beam computed tomography (CBCT) and panoramic radiographic (PAN) planning as compared to the surgical outcome. Materials and Methods One hundred and eight partially edentulous patients with a need for implant rehabilitation were referred for preoperative imaging. Imaging consisted of PAN and CBCT images. Four observers carried out implant planning using PAN image datasets, and at least one month later, using CBCT image datasets. Based on their own planning, the observers assessed the need for bone graft augmentation as well as complication prediction. The implant length and diameter, the need for bone graft augmentation, and the occurrence of anatomical complications during planning and implant placement were statistically compared. Results In the 108 patients, 365 implants were installed. Receiver operating characteristic analyses of both PAN and CBCT preoperative planning showed that CBCT performed better than PAN-based planning with respect to the need for bone graft augmentation and perioperative complications. The sensitivity and the specificity of CBCT for implant complications were 96.5% and 90.5%, respectively, and for bone graft augmentation, they were 95.2% and 96.3%, respectively. Significant differences were found between PAN-based planning and the surgery of posterior implant lengths. Conclusion Our findings indicated that CBCT-based preoperative implant planning enabled treatment planning with a higher degree of prediction and agreement as compared to the surgical standard. In PAN-based surgery, the prediction of implant length was poor. PMID:25279342

  17. Preoperative planning and postoperative evaluation of total hip arthroplasty that takes combined anteversion.

    PubMed

    Imai, Hiroshi; Miyawaki, Joji; Kamada, Tomomi; Takeba, Jun; Mashima, Naohiko; Miura, Hiromasa

    2016-07-01

    The purpose of this study was to investigate whether postoperative combined anteversion (CA) can be kept within the safe zone while using cementless total hip arthroplasty (THA) using the operative technique which prepares the socket first for developmental dysplasia of the hip (DDH), by estimating the anteversion of the metaphyseal fit stem using preoperative three-dimensional (3D) computerized planning and by adjusting the anteversion of the socket using a navigation system that considers CA. Our subjects were 65 patients (65 hips) that had undergone cementless THA for DDH that could be observed for 1 year or more. Clinical assessments were made using the Japanese Orthopaedic Association's (JOA) hip score. For a radiological evaluation, we investigated 3D-planned stem versions, postoperative stem versions, preoperative and postoperative CA, and the relationship between CA and dislocation tendencies with temporary intraoperative reductions. JOA hip scores improved from 52.3 ± 11.4 points to 88.9 ± 8.6 points. CT evaluations revealed that 3D-planned stem versions were strongly correlated with postoperative stem versions (r = 0.80; p < 0.01). Preoperative CA was 50.5° ± 7.2°, and postoperative CA was 41.3° ± 8.6°. Postoperative CA was kept within the safe zone in 61 hips. No intraoperative dislocation tendencies were observed in any hips. By estimating the anteversion of the cementless metaphyseal fit stem using 3D planning preoperatively and adjusting the angle of anteversion of the socket using a navigation system that considers CA intraoperatively, postoperative CA can very frequently be kept within the safe zone, even with cementless THA using the operative technique which prepares the socket first for DDH. PMID:27154291

  18. Distribution of Glenoid Implant Options for Correcting Deformities Using a Preoperative Planning Tool.

    PubMed

    Greene, Alexander; Jones, Richard B; Wright, Thomas W; Parsons, Ira M; Saadi, Paul; Cheung, Emilie V; Polakovic, Sandrine; Hamilton, Matthew A

    2015-12-01

    Preoperative planning tools in shoulder arthroplasty are a recently developing technology with the advantage of being able to clearly assess patient anatomy and deformities before entering the OR. Addressing retroverted glenoids remains one of the most difficult aspects of primary shoulder arthroplasty. In this study, five surgeons were provided with a preoperative planning tool with posterior augmented glenoid implant options (0°, 8°, and 16°) to treat 10 cadaveric cases with a range of versions from 7.8° anteversion to 25.1° retroversion. Surgeons were able to remove less bone using 8° augmented implants over standard non-augmented implants (2.8° reamed vs. 6.4° reamed) and were able to correct each case on average within ± 1.8° of neutral version. Slight glenoid vault perforation was observed in 18% of the plans. Eight degrees posterior augmented implants were used in scans averaging 9.0° retroversion, and 16° posterior augmented implants were used in scans averaging 20.6° retroversion. Results were then compared to 14 preoperative CT scans provided by one of the surgeons in which both 8° and 16° posterior augmented glenoid implants were used in actual patients, showing 8° posterior augmented implants were used in cases averaging 12.3° retroversion, and 16° posterior augmented implants were used in cases averaging 20.7° retroversion. The study shows that surgeons can effectively and predictably use a preoperative planning tool to correct glenoid abnormalities using augmented implant solutions while minimizing both scapular bone removal and vault perforation and maximizing version correction. PMID:26631197

  19. Sampling and analysis plan for the preoperational environmental survey for the immobilized low activity waste (ILAW) project W-465

    SciTech Connect

    Mitchell, R.M.

    1998-09-28

    This document provides a detailed description of the Sampling and Analysis Plan for the Preoperational Survey to be conducted at the Immobilized Low Activity Waste (ILAW) Project Site in the 200 East Area.

  20. The utility and precision of analogue and digital preoperative planning for total hip arthroplasty

    PubMed Central

    Comba, Fernando; Taveras, Nicole; Salvati, Eduardo A.

    2007-01-01

    We prospectively compared the utility and precision of preoperative templating performed in printed films (analogue) with that performed on digital radiographs (digital) in 69 patients undergoing primary total hip replacement. Five patients were excluded when misplacement of the marker resulted in a magnification error greater that 10%; in the remaining patients (64 hips), the cup size was within ± one size in 62 (97%) of the analogue and 52 (81%) of the digital (p = 0.01) plans. The stem size was within ± one size in 63 (98%) of the analogue and 60 (94%) of the digital (p = 0.39) plans. The distance from the proximal corner of the lesser trochanter to the center of the prosthetic head (LTCD) in the analogue differed by 5 mm or more from the digital plan in nine cases (14%). Analogue preoperative planning yielded more predictable results than digital planning, particularly in terms of acetabular component size and LTCD that dictates limb lengthening-shortening. The sources of error were not clearly explained by variations in magnification. Inconsistent positioning of the magnification marker may jeopardise the safe implementation of digital templating. PMID:17404731

  1. Use of 3-Dimensional Printing for Preoperative Planning in the Treatment of Recurrent Anterior Shoulder Instability

    PubMed Central

    Sheth, Ujash; Theodoropoulos, John; Abouali, Jihad

    2015-01-01

    Recurrent anterior shoulder instability often results from large bony Bankart or Hill-Sachs lesions. Preoperative imaging is essential in guiding our surgical management of patients with these conditions. However, we are often limited to making an attempt to interpret a 3-dimensional (3D) structure using conventional 2-dimensional imaging. In cases in which complex anatomy or bony defects are encountered, this type of imaging is often inadequate. We used 3D printing to produce a solid 3D model of a glenohumeral joint from a young patient with recurrent anterior shoulder instability and complex Bankart and Hill-Sachs lesions. The 3D model from our patient was used in the preoperative planning stages of an arthroscopic Bankart repair and remplissage to determine the depth of the Hill-Sachs lesion and the degree of abduction and external rotation at which the Hill-Sachs lesion engaged. PMID:26759768

  2. Multimodal image registration for preoperative planning and image-guided neurosurgical procedures.

    PubMed

    Risholm, Petter; Golby, Alexandra J; Wells, William

    2011-04-01

    Image registration is the process of transforming images acquired at different time points, or with different imaging modalities, into the same coordinate system. It is an essential part of any neurosurgical planning and navigation system because it facilitates combining images with important complementary, structural, and functional information to improve the information based on which a surgeon makes critical decisions. Brigham and Women's Hospital (BWH) has been one of the pioneers in developing intraoperative registration methods for aligning preoperative and intraoperative images of the brain. This article presents an overview of intraoperative registration and highlights some recent developments at BWH. PMID:21435571

  3. Preoperative planning for DIEP breast reconstruction: early experience of the use of computerised tomography angiography with VoNavix 3D software for perforator navigation.

    PubMed

    Pacifico, M D; See, M S; Cavale, N; Collyer, J; Francis, I; Jones, M E; Hazari, A; Boorman, J G; Smith, R W

    2009-11-01

    The deep inferior epigastric perforator (DIEP) flap is normally the first choice in breast reconstruction; however, due to the considerable vascular anatomical variation and the learning curve for the procedure, muscle-sparing transverse rectus abdominis musculocutaneous (TRAM) flaps are still frequently performed to reduce the rate of complications. Accurate preoperative investigation of the perforators would allow better operative preparation and possibly shorten the learning curve. In an effort to increase accuracy of preoperative planning and to aid preoperative decision-making in free abdominal flap breast reconstruction, we have acquired the use of VoNavix, software that creates three dimensional images from computerised tomography angiography (CTA) data. The use of the VoNavix software for analysis of CTA provides superior imaging that can be viewed in theatre. It, together with CTA, enables decisions to be made preoperatively, including: which side to raise the flap; whether to aim for a medial or lateral row perforator; whether to take a segment of muscle and whether to expect an easy or difficult dissection. We have now performed over 60 free abdominal flap breast reconstructions aided with CTA, and 10 of these cases also used VoNavix technology. This paper presents our initial experience with the use of this software, illustrated with three patient examples. The advantages and disadvantages are discussed. PMID:18708309

  4. Computer methods for automating preoperative dental implant planning: implant positioning and size assignment.

    PubMed

    Galanis, Christos C; Sfantsikopoulos, Michael M; Koidis, Petros T; Kafantaris, Nikolaos M; Mpikos, Pavlos G

    2007-04-01

    The paper presents computer-aided methods that allocate a dental implant and suggest its size, during the pre-operative planning stage, in conformance with introduced optimization criteria and established clinical requirements. Based on computed tomography data of the jaw and prosthesis anatomy, single tooth cases are planned for the best-suited implant insertion at a user-defined region. An optimum implantation axis line is produced and cylindrical implants of various candidate sizes are then automatically positioned, while their occlusal end is leveled to bone ridge, and evaluated. Radial safety margins are used for the assessment of the implant safety distance from neighboring anatomical structures and bone quantity and quality are estimated and taken into consideration. A case study demonstrates the concept and allows for its discussion. PMID:17267066

  5. Planned preoperative radiation therapy for advanced laryngeal carcinoma. [/sup 60/Co

    SciTech Connect

    Kazem, I.; van den Broek, P.; Huygen, P.L.M.

    1982-09-01

    One hundred ten patients with predominantly advanced laryngeal carcinoma were treated in the period 1969-1978 with planned preoperative radiation therapy followed by surgery. Site distribution was: 63 supraglottic, 26 glottic, 15 transglottic and 6 subglottic. There were 4 Stage II patients, 66 Stage III and 40 Stage IV. Preoperative radiation therapy consisted of Telecobalt irradiation to a total dose of 25 Gy given to a target volume encompassing the larynx and regional neck nodes, given in 5 equal daily fractions of 5 Gy in 5 consecutive days. Surgery was performed 2 days later. Total laryngectomy was performed on 48 patients, total laryngectomy with neck dissection on 55 patients, supraglottic laryngectomy on 5 and supraglottic laryngectomy with neck dissection on 2 patients. Crude actuarial 5 and 10 year survival probability for the whole group is 71 and 61%, respectively. The corrected 5 and 10 year survival is 75%. For patients with T/sub 3/-T/sub 4/-N/sub 0/ tumors 5 and 10 year survival probability is: crude 65 and 58%, and corrected 70% respectively. For T/sub 3/-T/sub 4/-N/sub +/ crude: 75 and 60% and corrected: 78%. Of 110 patients, one died postoperative, three died of intercurrent disease, five died as a result of second malignancy, and 23 died of their larynx carcinoma: 12/23 because of locoregional failure, and 11/23 because of distant metastasis. We concluded that short intensive preoperative radiation therapy and surgery offer a high cure rate in the treatment of advanced resectable laryngeal carcinoma. The merits of this technique are outlined in the text.

  6. Correlation between nipple elevation and breast resection weight: How to preoperatively plan breast reduction.

    PubMed

    Moio, Mariagrazia; Schonauer, Fabrizio

    2015-08-01

    Breast hypertrophy is often associated with functional limitations. Beyond the aesthetic concerns, breast reduction can improve symptoms and self-esteem. In different countries, health-care system regulations have fixed the threshold for reimbursement in 500 g of predicted tissue resection for each breast. Different preoperative measurements have been proposed to predict breast-tissue weight to be removed, showing a variable correlation with post-operative evaluation. We describe a reliable, simple measurement to predict the quantity of breast reduction in grams, which can be applicable to any surgical technique. A total of 128 patients undergoing bilateral breast reduction were evaluated. The correlation between the preoperative nipple-areola complex (NAC) lift distance and the weight of removed breast tissue was tested with linear regression and Pearson's test. Other anthropometric measurements were tested as a control. The ratio between resected grams and lift distance was explored to find a multiplication coefficient to be used at preoperative planning. The mean resection weight was 686.65 g. The mean NAC-lift distance was 7.6 cm. Positive correlation between the NAC-lift distance and the weight of breast tissue removed was found (r: 0.87; p < 0.001). The mean weight of the removed breast tissue (g) per centimetre of NAC lift was 81 g/cm in the group between 6 and 12 cm and 70 g/cm in the group with >12 cm of lift distance. The NAC-lift distance is a single, objective, repeatable measure that can provide a reliable prediction of breast-tissue grams to be removed; it helps in classifying breast-reduction indications. PMID:25997557

  7. Titanium-bone-anchored penile epithesis: preoperative planning and immediate postoperative results.

    PubMed

    Selvaggi, Gennaro; Branemark, Rickard; Elander, Anna; Liden, Mattias; Stalfors, Joacim

    2015-02-01

    The principle of osseointegration is accepted and used in reconstructive surgery. This study presents the first series of five patients where titanium implants have been implanted into the pubic bones of female-to-male (FTM) transsexual patients, in order to attach a "bone-anchored" penile epithesis. Following patient selection based on patients' wishes, pubic bones of 10 FTM transsexuals were analysed by CT-scan and a virtual planning was made. A surgical plan was also developed. To date, five FTM transsexuals have undergone the two-stage surgery. During stage-1, two titanium implants ("fixtures") are implanted onto the pubic bone. Four weeks postop, a new CT scan is performed to analyze osseointegration and the final implant position. During stage-2, the soft tissue of the pubic area is reduced; abutments are inserted and passed through the skin. A few weeks after stage 2 surgery, a penile epithesis is connected to the skin-penetrating titanium implants. Two out of 10 patients who received preoperative CT scan presented with smaller pubic bones, not able to accommodate the fixtures as chosen originally. Preoperative virtual planning is crucial for the selection of the appropriate implants size. The stage-1 and stage-2 surgery occurred uneventfully in all five patients. One patient presented with a wound infection 1 week after stage-2 surgery. Postoperative CT scan demonstrates implant osseointegration in all cases. This experimental clinical study demonstrates that titanium osseointegration is feasible onto the pubic bone. This new approach for penile reconstruction constitutes another alternative for both transsexual patients and cases following genital development disorders, post-trauma and surgery. PMID:24931337

  8. Preoperative computed tomography angiography for planning DIEP flap breast reconstruction reduces operative time and overall complications

    PubMed Central

    Rozen, Warren Matthew; Chowdhry, Muhammad; Band, Bassam; Ramakrishnan, Venkat V.; Griffiths, Matthew

    2016-01-01

    requiring a return to theatre in the immediate postoperative period. Modern scanners and techniques can reduce the level of ionising radiation, facilitating patients being able to benefit from the advantages that this preoperative planning can convey. PMID:27047777

  9. Planned preoperative radiation therapy vs. definitive radiotherapy for advanced laryngeal carcinoma

    SciTech Connect

    Kazem, I.; van den Broek, P.

    1984-10-01

    In the period 1970-1980 inclusive, 191 patients with T3T4 laryngeal carcinoma (glottic: 63 and supraglottic: 128) received either definitive radiation therapy (RT) (60-65 Gy in 6-7 weeks) or planned preoperative radiation therapy (25 Gy in 5 equal daily fractions of 5 Gy) followed by laryngectomy with or without neck dissection (RT + S). Selection for RT vs. RT + S was based on medical operability and/or patient's refusal to undergo surgery. All patients are evaluable with minimum of 2 years observation. Crude 5 and 10-year survival probability for 32 patients with glottic localization who received RT is 55% and 38% vs. 65% and 65% respectively for 31 treated with RT + S. For 52 patients with supraglottic site who received RT, the 5 and 10-year survival is 44% and 44% vs. 82% and 60% for 76 patients treated with RT + S.

  10. Three-dimensional printing for preoperative planning of total hip arthroplasty revision: case report.

    PubMed

    Zerr, Joseph; Chatzinoff, Yonatan; Chopra, Rajiv; Estrera, Kenneth; Chhabra, Avneesh

    2016-10-01

    Three dimensional (3D) printing can be used to create material models to aid preoperative planning of complex orthopedic procedures as exemplified by this case of total hip arthroplasty failure due to infection with resulting severe acetabular bone stock deficiency. The 3D model allowed for trialing of the acetabular component to determine cup size, position, and screw placement. Most importantly, the model confirmed that there was not a pelvic discontinuity and the revision shell would be sufficient for the reconstruction. Previously, the cost and complexity of utilization of 3D printers were prohibitive. Recent improvements in commercially available 3D printers have made rapid prototype model creation a realistic option, which can facilitate difficult surgery. PMID:27480617

  11. A spatial model of the knee for the preoperative planning of knee surgery.

    PubMed

    Olanlokun, K F T; Wills, D P M

    2002-01-01

    A model on the spatial mechanical behaviour of the passive knee is presented. The femoral articular surfaces were represented by generalized, sagittally elliptical, toroidal surfaces. The medial and lateral tibial articular surfaces were represented by a dished spherical surface and the lower hemihyperbolic region of a torus respectively. Anatomical articular cartilage, knee ligaments and the posterior capsule were represented by spring-like deformable elements with non-linear load versus deflection characteristics. All the forces that act on the femur relative to the tibia were represented by three orthogonal forces and three associated moments. Spatial, articulation-dependent femorotibial kinematic constraint equations of the passive knee were formulated in an analytically explicit manner, based on the natural coordinates of the articular surfaces. The constraint equations were solved algebraically in closed form. Equations were derived that describe spatial femoro-tibial motion, ligament length, ligament strain, ligament-based elastic potential energy and the quasi-static equilibrium of the passive knee. Software was written, simulations on the motion characteristics and load versus deflection characteristics of the knee were carried out and graphical results were presented. The simulation of planar flexion/extension was almost spontaneous. The time taken to simulate spatial six-degree-of-freedom femoro-tibial motion was less than 2.5 min. The models were found to be capable of representing real-life passive knees to a high degree of satisfaction. It has been demonstrated that the models can provide knee surgeons with additional information on major aspects of the preoperative planning of knee surgery. The models can be used to enhance the preoperative planning of ligament reconstruction, articular surfaces related surgery, osteotomy and patellar tendon transfer surgery. PMID:11908484

  12. Computer-assisted preoperative planning of a novel design of total ankle replacement.

    PubMed

    Leardini, Alberto; Rapagnà, Luca; Ensini, Andrea; Catani, Fabio; Cappello, Angelo

    2002-03-01

    Computer-assisted preoperative planning are particularly sought for enhancing surgical implantation and improving clinical outcome of ankle joint replacement arthroplasty. A planning tool was designed to enhance the surgical implantation of a novel ligament-compatible three-component prosthesis. The tool includes a geometric and mechanical model of the ankle complex. The geometry of the articular surfaces and of main ligaments is defined from digitisation on a scanned lateral radiographs of the joint. From the expected movement arc and from component dimensions, a mechanical model of the ligaments is used to select the optimal size and the position the three prosthesis components. The planning is based on the minimisation of ligament change in length and of bone stock to be removed. The main output report is a detailed picture of the replaced ankle with indications of component locations and quantitative measure of bone cuts. An advanced report also superimposes the resulting prediction of prosthesis component kinematics at the replaced joint to the original radiographs. PMID:11853950

  13. Careful Planning Key to Accurate Fixed Reports Assets.

    ERIC Educational Resources Information Center

    MaRous, Arnold M.

    1986-01-01

    Only with careful planning can school business managers develop fixed asset information and good recordkeeping. Use of a simple inventory system and discussion with school districts already utilizing this system will assist planning. (CJH)

  14. Pre-operative simulation and post-operative validation of soft-tissue deformations for breast implantation planning

    NASA Astrophysics Data System (ADS)

    Roose, Liesbet; De Maerteleire, Wim; Mollemans, Wouter; Maes, Frederik; Suetens, Paul

    2006-03-01

    Virtual surgery simulation plays an increasingly important role as a planning aid for the surgeon. A reliable simulation method to predict the surgical outcome of breast reconstruction and breast augmentation procedures does not yet exist. However, a method to pre-operatively assess the result of the procedure would be useful to ensure a symmetrical and naturally looking result, and could be a practical means of communication with the patient. In this paper, we present a basic framework to simulate a subglandular breast implantation. First, we propose a method to build a model of the patient's anatomy, based on a 3D picture of the skin surface in combination with thickness estimates of the soft tissue surrounding the breast. This approach is cheap, fast and the picture can be taken while the patient is standing upright, which makes it advantageous compared to conventional CTor MR-based methods. Second, a set of boundary conditions is defined to mimic the effect of the implant. Finally, we compute the new equilibrium geometry using the iterative FEM-based Mass Tensor Method, which is computationally more effcient than the traditional FEM approach since sufficient precision can be achieved with a limited number of iterations. We illustrate our approach with a preliminary validation study on 4 patients. We obtain promising results with a mean error between the simulated and the true post-operative breast geometry below 4 mm and maximal error below 10 mm, which is found to be sufficiently accurate for visual assessment in clinical practice.

  15. A computational tool for preoperative breast augmentation planning in aesthetic plastic surgery.

    PubMed

    Georgii, Joachim; Eder, Maximilian; Bürger, Kai; Klotz, Sebastian; Ferstl, Florian; Kovacs, Laszlo; Westermann, Rüdiger

    2014-05-01

    Breast augmentation was the most commonly performed cosmetic surgery procedure in 2011 in the United States. Although aesthetically pleasing surgical results can only be achieved if the correct breast implant is selected from a large variety of different prosthesis sizes and shapes available on the market, surgeons still rely on visual assessment and other subjective approaches for operative planning because of lacking objective evaluation tools. In this paper, we present the development of a software prototype for augmentation mammaplasty simulation solely based on 3-D surface scans, from which patient-specific finite-element models are generated in a semiautomatic process. The finite-element model is used to preoperatively simulate the expected breast shapes using physical soft-tissue mechanics. Our approach uses a novel mechanism based on so-called displacement templates, which, for a specific implant shape and position, describe the respective internal body forces. Due to a highly efficient numerical solver we can provide immediate visual feedback of the simulation results, and thus, the software prototype can be integrated smoothly into the medical workflow. The clinical value of the developed 3-D computational tool for aesthetic breast augmentation surgery planning is demonstrated in patient-specific use cases. PMID:24132029

  16. Pre-operative segmentation of neck CT datasets for the planning of neck dissections

    NASA Astrophysics Data System (ADS)

    Cordes, Jeanette; Dornheim, Jana; Preim, Bernhard; Hertel, Ilka; Strauss, Gero

    2006-03-01

    For the pre-operative segmentation of CT neck datasets, we developed the software assistant NeckVision. The relevant anatomical structures for neck dissection planning can be segmented and the resulting patient-specific 3D-models are visualized afterwards in another software system for intervention planning. As a first step, we examined the appropriateness of elementary segmentation techniques based on gray values and contour information to extract the structures in the neck region from CT data. Region growing, interactive watershed transformation and live-wire are employed for segmentation of different target structures. It is also examined, which of the segmentation tasks can be automated. Based on this analysis, the software assistant NeckVision was developed to optimally support the workflow of image analysis for clinicians. The usability of NeckVision was tested within a first evaluation with four otorhinolaryngologists from the university hospital of Leipzig, four computer scientists from the university of Magdeburg and two laymen in both fields.

  17. Sampling and analysis plan for the preoperational environmental survey of the spent nuclear fuel project facilities

    SciTech Connect

    MITCHELL, R.M.

    1999-04-01

    This sampling and analysis plan will support the preoperational environmental monitoring for construction, development, and operation of the Spent Nuclear Fuel (SNF) Project facilities, which have been designed for the conditioning and storage of spent nuclear fuels; particularly the fuel elements associated with the operation of N-Reactor. The SNF consists principally of irradiated metallic uranium, and therefore includes plutonium and mixed fission products. The primary effort will consist of removing the SNF from the storage basins in K East and K West Areas, placing in multicanister overpacks, vacuum drying, conditioning, and subsequent dry vault storage in the 200 East Area. The primary purpose and need for this action is to reduce the risks to public health and safety and to the environment. Specifically these include prevention of the release of radioactive materials into the air or to the soil surrounding the K Basins, prevention of the potential migration of radionuclides through the soil column to the nearby Columbia River, reduction of occupational radiation exposure, and elimination of the risks to the public and to workers from the deterioration of SNF in the K Basins.

  18. Transzygomatic approach for the resection of large condylar osteochondromas using computer-assisted preoperative planning.

    PubMed

    Ye, Z-X; Yang, C; Chen, M-J

    2016-09-01

    The purpose of this study was to evaluate the outcomes of patients with large osteochondromas (OCs) treated via transzygomatic approach for exposure and local resection. All patients with large OCs treated by transzygomatic approach from 2006 through 2014 were investigated. The inclusion criteria were (1) condylar OC of exogenous type; (2) a mass that could be treated only via transzygomatic approach, as assessed using computer-assisted preoperative planning. The preliminary results evaluated included recurrence, joint form and function, occurrence of facial deformity, facial nerve function, and the condition of the zygomatic arch fixation. Other parameters assessed included tumour size and location and the length of follow-up. Ten patients with OCs were included in this study. All masses were located anteromedial to the condyle; the average maximal diameter was 33.15mm. During follow-up (average 28.5 months), the average maximum inter-incisal opening increased from 25.4mm to 32.0mm. Nine patients recovered without recurrence, a change in occlusion, secondary deformity, or nerve dysfunction. One patient had severe disc perforation and condylar resorption. The transzygomatic approach is applicable for the resection of large condylar OCs protruding anteromedially into the infratemporal space. Surgical simulations may help to identify the indications for this approach and to design the surgery. PMID:27131594

  19. Complete, accurate, mammalian phylogenies aid conservation planning, but not much

    PubMed Central

    Rodrigues, Ana S. L.; Grenyer, Richard; Baillie, Jonathan E. M.; Bininda-Emonds, Olaf R. P.; Gittlemann, John L.; Hoffmann, Michael; Safi, Kamran; Schipper, Jan; Stuart, Simon N.; Brooks, Thomas

    2011-01-01

    In the face of unprecedented global biodiversity loss, conservation planning must balance between refining and deepening knowledge versus acting on current information to preserve species and communities. Phylogenetic diversity (PD), a biodiversity measure that takes into account the evolutionary relationships between species, is arguably a more meaningful measure of biodiversity than species diversity, but cannot yet be applied to conservation planning for the majority of taxa for which phylogenetic trees have not yet been developed. Here, we investigate how the quality of data on the taxonomy and/or phylogeny of species affects the results of spatial conservation planning in terms of the representation of overall mammalian PD. The results show that the better the quality of the biodiversity data the better they can serve as a basis for conservation planning. However, decisions based on incomplete data are remarkably robust across different levels of degrading quality concerning the description of new species and the availability of phylogenetic information. Thus, given the level of urgency and the need for action, conservation planning can safely make use of the best available systematic data, limited as these data may be. PMID:21844044

  20. Digital correction of magnification in pelvic x rays for preoperative planning of hip joint replacements: Theoretical development and clinical results of a new protocol

    SciTech Connect

    The, B.; Diercks, R.L.; Stewart, R.E.; Ooijen, P.M.A. van; Horn, J.R. van

    2005-08-15

    The introduction of digital radiological facilities leads to the necessity of digital preoperative planning, which is an essential part of joint replacement surgery. To avoid errors in the preparation and execution of hip surgery, reliable correction of the magnification of the projected hip is a prerequisite. So far, no validated method exists to accomplish this. We present validated geometrical models of the x-ray projection of spheres, relevant for the calibration procedure to correct for the radiographic magnification. With help of these models a new calibration protocol was developed. The validity and precision of this procedure was determined in clinical practice. Magnification factors could be predicted with a maximal margin of error of 1.5%. The new calibration protocol is valid and reliable. The clinical tests revealed that correction of magnification has a 95% margin of error of -3% to +3%. Future research might clarify if a strict calibration protocol, as presented in this study, results in more accurate preoperative planning of hip joint replacements.

  1. A pre-operative planning for endoprosthetic human tracheal implantation: a decision support system based on robust design of experiments.

    PubMed

    Trabelsi, O; Villalobos, J L López; Ginel, A; Cortes, E Barrot; Doblaré, M

    2014-05-01

    Swallowing depends on physiological variables that have a decisive influence on the swallowing capacity and on the tracheal stress distribution. Prosthetic implantation modifies these values and the overall performance of the trachea. The objective of this work was to develop a decision support system based on experimental, numerical and statistical approaches, with clinical verification, to help the thoracic surgeon in deciding the position and appropriate dimensions of a Dumon prosthesis for a specific patient in an optimal time and with sufficient robustness. A code for mesh adaptation to any tracheal geometry was implemented and used to develop a robust experimental design, based on the Taguchi's method and the analysis of variance. This design was able to establish the main swallowing influencing factors. The equations to fit the stress and the vertical displacement distributions were obtained. The resulting fitted values were compared to those calculated directly by the finite element method (FEM). Finally, a checking and clinical validation of the statistical study were made, by studying two cases of real patients. The vertical displacements and principal stress distribution obtained for the specific tracheal model were in agreement with those calculated by FE simulations with a maximum absolute error of 1.2 mm and 0.17 MPa, respectively. It was concluded that the resulting decision support tool provides a fast, accurate and simple tool for the thoracic surgeon to predict the stress state of the trachea and the reduction in the ability to swallow after implantation. Thus, it will help them in taking decisions during pre-operative planning of tracheal interventions. PMID:23046526

  2. Efficacy of stereoscopic visualization and six degrees of freedom interaction in preoperative planning of total hip replacement.

    PubMed

    Testi, Debora; Lattanzi, Riccardo; Benvegnù, Marco; Petrone, Marco; Zannoni, Cinzia; Viceconti, Marco; Toni, Aldo

    2006-09-01

    The aim of this study was to assess the accuracy of a six-degrees-of-freedom application for pre-operative planning of total hip replacement in a virtual reality (VR) environment. A test was performed estimating the system inherent accuracy. The users can move objects in the VR environment with an intrinsic accuracy almost four orders of magnitude greater than the object dimension. A second unambiguous and relevant task was defined to assess the accuracy achievable with the interface in a specific planning task. The results were compared with those obtained with 2D interfaces for both the stem and the cup component. The RMSE was assumed as an indicator of the achievable accuracy. The accuracy of the immersive interface was comparable with that achievable with a standard mouse - monitor interface. The users were consistent using the VR interface, confirming the high usability of the new interface and the steep learning curve of users unfamiliar with the new environment. This study has demonstrated that the application of VR environment for pre-operative planning of total hip replacement may help to shorten the duration of the positioning and to yield consistent results even with first-time users. PMID:16954057

  3. PET/MRI for Preoperative Planning in Patients with Soft Tissue Sarcoma: A Technical Report of Two Patients

    PubMed Central

    Loft, Annika; Jensen, Karl Erik; Daugaard, Søren; Petersen, Michael M.

    2013-01-01

    Clinical positron emission tomography (PET)/magnetic resonance imaging (MRI) acquisition protocols may improve the evaluation of soft tissue sarcomas (STS) prior to surgical planning. We examined two patients with lower extremity STS using a Siemens Biograph mMR PET/MRI scanner and the glucose analogue 18F-fluoro-deoxyglucose (FDG). We investigated clinically relevant tumor volumes and evaluated the relations to skeletal periosteum and nerve bundles. The patient scans suggest that FDG PET/MRI improved the edge detection, and invasion of tumor tissue into important adjacent anatomical structures can be evaluated. FDG PET/MRI also provided additional information compared to conventional Gadolinium enhanced MR imaging. The findings were proven by subsequent pathological examination of the resected tumor tissue. In the future, clinical FDG PET/MRI may be an important modality for preoperative planning, including radiation therapy planning in patients with STS. PMID:24368921

  4. An Approach for Preoperative Planning and Performance of MR-guided Interventions Demonstrated With a Manual Manipulator in a 1.5T MRI Scanner

    SciTech Connect

    Seimenis, Ioannis; Tsekos, Nikolaos V.; Keroglou, Christoforos; Eracleous, Eleni; Pitris, Constantinos; Christoforou, Eftychios G.

    2012-04-15

    Purpose: The aim of this work was to develop and test a general methodology for the planning and performance of robot-assisted, MR-guided interventions. This methodology also includes the employment of software tools with appropriately tailored routines to effectively exploit the capabilities of MRI and address the relevant spatial limitations. Methods: The described methodology consists of: (1) patient-customized feasibility study that focuses on the geometric limitations imposed by the gantry, the robotic hardware, and interventional tools, as well as the patient; (2) stereotactic preoperative planning for initial positioning of the manipulator and alignment of its end-effector with a selected target; and (3) real-time, intraoperative tool tracking and monitoring of the actual intervention execution. Testing was performed inside a standard 1.5T MRI scanner in which the MR-compatible manipulator is deployed to provide the required access. Results: A volunteer imaging study demonstrates the application of the feasibility stage. A phantom study on needle targeting is also presented, demonstrating the applicability and effectiveness of the proposed preoperative and intraoperative stages of the methodology. For this purpose, a manually actuated, MR-compatible robotic manipulation system was used to accurately acquire a prescribed target through alternative approaching paths. Conclusions: The methodology presented and experimentally examined allows the effective performance of MR-guided interventions. It is suitable for, but not restricted to, needle-targeting applications assisted by a robotic manipulation system, which can be deployed inside a cylindrical scanner to provide the required access to the patient facilitating real-time guidance and monitoring.

  5. Acute small bowel toxicity and preoperative chemoradiotherapy for rectal cancer: Investigating dose-volume relationships and role for inverse planning

    SciTech Connect

    Tho, Lye Mun . E-mail: l.tho@beatson.gla.ac.uk; Glegg, Martin; Paterson, Jennifer; Yap, Christina; MacLeod, Alice; McCabe, Marie; McDonald, Alexander C.

    2006-10-01

    Purpose: The relationship between volume of irradiated small bowel (VSB) and acute toxicity in rectal cancer radiotherapy is poorly quantified, particularly in patients receiving concurrent preoperative chemoradiotherapy. Using treatment planning data, we studied a series of such patients. Methods and Materials: Details of 41 patients with locally advanced rectal cancer were reviewed. All received 45 Gy in 25 fractions over 5 weeks, 3-4 fields three-dimensional conformal radiotherapy with daily 5-fluorouracil and folinic acid during Weeks 1 and 5. Toxicity was assessed prospectively in a weekly clinic. Using computed tomography planning software, the VSB was determined at 5 Gy dose intervals (V{sub 5}, V{sub 1}, etc.). Eight patients with maximal VSB had dosimetry and radiobiological modeling outcomes compared between inverse and conformal three-dimensional planning. Results: VSB correlated strongly with diarrheal severity at every dose level (p < 0.03), with strongest correlation at lowest doses. Median VSB differed significantly between patients experiencing Grade 0-1 and Grade 2-4 diarrhea (p {<=} 0.05). No correlation was found with anorexia, nausea, vomiting, abdominal cramps, age, body mass index, sex, tumor position, or number of fields. Analysis of 8 patients showed that inverse planning reduced median dose to small bowel by 5.1 Gy (p = 0.008) and calculated late normal tissue complication probability (NTCP) by 67% (p = 0.016). We constructed a model using mathematical analysis to predict for acute diarrhea occurring at V{sub 5} and V{sub 15}. Conclusions: A strong dose-volume relationship exists between VSB and acute diarrhea at all dose levels during preoperative chemoradiotherapy. Our constructed model may be useful in predicting toxicity, and this has been derived without the confounding influence of surgical excision on bowel function. Inverse planning can reduce calculated dose to small bowel and late NTCP, and its clinical role warrants further

  6. Atlas and feature based 3D pathway visualization enhancement for skull base pre-operative fast planning from head CT

    NASA Astrophysics Data System (ADS)

    Aghdasi, Nava; Li, Yangming; Berens, Angelique; Moe, Kris S.; Bly, Randall A.; Hannaford, Blake

    2015-03-01

    Minimally invasive neuroendoscopic surgery provides an alternative to open craniotomy for many skull base lesions. These techniques provides a great benefit to the patient through shorter ICU stays, decreased post-operative pain and quicker return to baseline function. However, density of critical neurovascular structures at the skull base makes planning for these procedures highly complex. Furthermore, additional surgical portals are often used to improve visualization and instrument access, which adds to the complexity of pre-operative planning. Surgical approach planning is currently limited and typically involves review of 2D axial, coronal, and sagittal CT and MRI images. In addition, skull base surgeons manually change the visualization effect to review all possible approaches to the target lesion and achieve an optimal surgical plan. This cumbersome process relies heavily on surgeon experience and it does not allow for 3D visualization. In this paper, we describe a rapid pre-operative planning system for skull base surgery using the following two novel concepts: importance-based highlight and mobile portal. With this innovation, critical areas in the 3D CT model are highlighted based on segmentation results. Mobile portals allow surgeons to review multiple potential entry portals in real-time with improved visualization of critical structures located inside the pathway. To achieve this we used the following methods: (1) novel bone-only atlases were manually generated, (2) orbits and the center of the skull serve as features to quickly pre-align the patient's scan with the atlas, (3) deformable registration technique was used for fine alignment, (4) surgical importance was assigned to each voxel according to a surgical dictionary, and (5) pre-defined transfer function was applied to the processed data to highlight important structures. The proposed idea was fully implemented as independent planning software and additional

  7. Computed tomography for preoperative planning in minimal-invasive total hip arthroplasty: radiation exposure and cost analysis.

    PubMed

    Huppertz, Alexander; Radmer, Sebastian; Asbach, Patrick; Juran, Ralf; Schwenke, Carsten; Diederichs, Gerd; Hamm, Bernd; Sparmann, Martin

    2011-06-01

    Computed tomography (CT) was used for preoperative planning of minimal-invasive total hip arthroplasty (THA). 92 patients (50 males, 42 females, mean age 59.5 years) with a mean body-mass-index (BMI) of 26.5 kg/m(2) underwent 64-slice CT to depict the pelvis, the knee and the ankle in three independent acquisitions using combined x-, y-, and z-axis tube current modulation. Arthroplasty planning was performed using 3D-Hip Plan(®) (Symbios, Switzerland) and patient radiation dose exposure was determined. The effects of BMI, gender, and contralateral THA on the effective dose were evaluated by an analysis-of-variance. A process-cost-analysis from the hospital perspective was done. All CT examinations were of sufficient image quality for 3D-THA planning. A mean effective dose of 4.0 mSv (SD 0.9 mSv) modeled by the BMI (p<0.0001) was calculated. The presence of a contralateral THA (9/92 patients; p=0.15) and the difference between males and females were not significant (p=0.08). Personnel involved were the radiologist (4 min), the surgeon (16 min), the radiographer (12 min), and administrative personnel (4 min). A CT operation time of 11 min and direct per-patient costs of 52.80 € were recorded. Preoperative CT for THA was associated with a slight and justifiable increase of radiation exposure in comparison to conventional radiographs and low per-patient costs. PMID:20022723

  8. Does cone-beam CT alter treatment plans? Comparison of preoperative implant planning using panoramic versus cone-beam CT images

    PubMed Central

    Guerrero, Maria Eugenia; Noriega, Jorge; Castro, Carmen

    2014-01-01

    Purpose The present study was performed to compare the planning of implant placement based on panoramic radiography (PAN) and cone-beam computed tomography (CBCT) images, and to study the impact of the image dataset on the treatment planning. Materials and Methods One hundred five partially edentulous patients (77 males, 28 females, mean age: 46 years, range: 26-67 years) seeking oral implant rehabilitation were referred for presurgical imaging. Imaging consisted of PAN and CBCT imaging. Four observers planned implant treatment based on the two-dimensional (2D) image datasets and at least one month later on the three-dimensional (3D) image dataset. Apart from presurgical diagnostic and dimensional measurement tasks, the observers needed to indicate the surgical confidence levels and assess the image quality in relation to the presurgical needs. Results All observers confirmed that both imaging modalities (PAN and CBCT) gave similar values when planning implant diameter. Also, the results showed no differences between both imaging modalities for the length of implants with an anterior location. However, significant differences were found in the length of implants with a posterior location. For implant dimensions, longer lengths of the implants were planned with PAN, as confirmed by two observers. CBCT provided images with improved scores for subjective image quality and surgical confidence levels. Conclusion Within the limitations of this study, there was a trend toward PAN-based preoperative planning of implant placement leading towards the use of longer implants within the posterior jaw bone. PMID:24944961

  9. 3D-printed haptic "reverse" models for preoperative planning in soft tissue reconstruction: a case report.

    PubMed

    Chae, Michael P; Lin, Frank; Spychal, Robert T; Hunter-Smith, David J; Rozen, Warren Matthew

    2015-02-01

    In reconstructive surgery, preoperative planning is essential for optimal functional and aesthetic outcome. Creating a three-dimensional (3D) model from two-dimensional (2D) imaging data by rapid prototyping has been used in industrial design for decades but has only recently been introduced for medical application. 3D printing is one such technique that is fast, convenient, and relatively affordable. In this report, we present a case in which a reproducible method for producing a 3D-printed "reverse model" representing a skin wound defect was used for flap design and harvesting. This comprised a 82-year-old man with an exposed ankle prosthesis after serial soft tissue debridements for wound infection. Soft tissue coverage and dead-space filling were planned with a composite radial forearm free flap (RFFF). Computed tomographic angiography (CTA) of the donor site (left forearm), recipient site (right ankle), and the left ankle was performed. 2D data from the CTA was 3D-reconstructed using computer software, with a 3D image of the left ankle used as a "control." A 3D model was created by superimposing the left and right ankle images, to create a "reverse image" of the defect, and printed using a 3D printer. The RFFF was thus planned and executed effectively, without complication. To our knowledge, this is the first report of a mechanism of calculating a soft tissue wound defect and producing a 3D model that may be useful for surgical planning. 3D printing and particularly "reverse" modeling may be versatile options in reconstructive planning, and have the potential for broad application. PMID:25046728

  10. Resting-State Functional Magnetic Resonance Imaging for Language Preoperative Planning

    PubMed Central

    Branco, Paulo; Seixas, Daniela; Deprez, Sabine; Kovacs, Silvia; Peeters, Ronald; Castro, São L.; Sunaert, Stefan

    2016-01-01

    Functional magnetic resonance imaging (fMRI) is a well-known non-invasive technique for the study of brain function. One of its most common clinical applications is preoperative language mapping, essential for the preservation of function in neurosurgical patients. Typically, fMRI is used to track task-related activity, but poor task performance and movement artifacts can be critical limitations in clinical settings. Recent advances in resting-state protocols open new possibilities for pre-surgical mapping of language potentially overcoming these limitations. To test the feasibility of using resting-state fMRI instead of conventional active task-based protocols, we compared results from fifteen patients with brain lesions while performing a verb-to-noun generation task and while at rest. Task-activity was measured using a general linear model analysis and independent component analysis (ICA). Resting-state networks were extracted using ICA and further classified in two ways: manually by an expert and by using an automated template matching procedure. The results revealed that the automated classification procedure correctly identified language networks as compared to the expert manual classification. We found a good overlay between task-related activity and resting-state language maps, particularly within the language regions of interest. Furthermore, resting-state language maps were as sensitive as task-related maps, and had higher specificity. Our findings suggest that resting-state protocols may be suitable to map language networks in a quick and clinically efficient way. PMID:26869899

  11. Resting-State Functional Magnetic Resonance Imaging for Language Preoperative Planning.

    PubMed

    Branco, Paulo; Seixas, Daniela; Deprez, Sabine; Kovacs, Silvia; Peeters, Ronald; Castro, São L; Sunaert, Stefan

    2016-01-01

    Functional magnetic resonance imaging (fMRI) is a well-known non-invasive technique for the study of brain function. One of its most common clinical applications is preoperative language mapping, essential for the preservation of function in neurosurgical patients. Typically, fMRI is used to track task-related activity, but poor task performance and movement artifacts can be critical limitations in clinical settings. Recent advances in resting-state protocols open new possibilities for pre-surgical mapping of language potentially overcoming these limitations. To test the feasibility of using resting-state fMRI instead of conventional active task-based protocols, we compared results from fifteen patients with brain lesions while performing a verb-to-noun generation task and while at rest. Task-activity was measured using a general linear model analysis and independent component analysis (ICA). Resting-state networks were extracted using ICA and further classified in two ways: manually by an expert and by using an automated template matching procedure. The results revealed that the automated classification procedure correctly identified language networks as compared to the expert manual classification. We found a good overlay between task-related activity and resting-state language maps, particularly within the language regions of interest. Furthermore, resting-state language maps were as sensitive as task-related maps, and had higher specificity. Our findings suggest that resting-state protocols may be suitable to map language networks in a quick and clinically efficient way. PMID:26869899

  12. PRE-OPERATIVE PLANNING AND SURGICAL TECHNIQUE OF THE OPEN WEDGE SUPRACONDYLAR OSTEOTOMY FOR CORRECTION OF VALGUS KNEE AND FIXATION WITH A FIXED-ANGLE IMPLANT

    PubMed Central

    Paccola, Cleber Antonio Jansen

    2015-01-01

    The step-by-step preoperative planning for supracondylar opening wedge osteotomy of the femur for precise correction of the load axis of the lower limb using a fixed-angle implant (95° AO blade plate) is presented. The surgical technique and the use of a bone graft from the same site for filling in the defect are also presented. PMID:27026976

  13. Fast and accurate sensitivity analysis of IMPT treatment plans using Polynomial Chaos Expansion

    NASA Astrophysics Data System (ADS)

    Perkó, Zoltán; van der Voort, Sebastian R.; van de Water, Steven; Hartman, Charlotte M. H.; Hoogeman, Mischa; Lathouwers, Danny

    2016-06-01

    The highly conformal planned dose distribution achievable in intensity modulated proton therapy (IMPT) can severely be compromised by uncertainties in patient setup and proton range. While several robust optimization approaches have been presented to address this issue, appropriate methods to accurately estimate the robustness of treatment plans are still lacking. To fill this gap we present Polynomial Chaos Expansion (PCE) techniques which are easily applicable and create a meta-model of the dose engine by approximating the dose in every voxel with multidimensional polynomials. This Polynomial Chaos (PC) model can be built in an automated fashion relatively cheaply and subsequently it can be used to perform comprehensive robustness analysis. We adapted PC to provide among others the expected dose, the dose variance, accurate probability distribution of dose-volume histogram (DVH) metrics (e.g. minimum tumor or maximum organ dose), exact bandwidths of DVHs, and to separate the effects of random and systematic errors. We present the outcome of our verification experiments based on 6 head-and-neck (HN) patients, and exemplify the usefulness of PCE by comparing a robust and a non-robust treatment plan for a selected HN case. The results suggest that PCE is highly valuable for both research and clinical applications.

  14. Fast and accurate sensitivity analysis of IMPT treatment plans using Polynomial Chaos Expansion.

    PubMed

    Perkó, Zoltán; van der Voort, Sebastian R; van de Water, Steven; Hartman, Charlotte M H; Hoogeman, Mischa; Lathouwers, Danny

    2016-06-21

    The highly conformal planned dose distribution achievable in intensity modulated proton therapy (IMPT) can severely be compromised by uncertainties in patient setup and proton range. While several robust optimization approaches have been presented to address this issue, appropriate methods to accurately estimate the robustness of treatment plans are still lacking. To fill this gap we present Polynomial Chaos Expansion (PCE) techniques which are easily applicable and create a meta-model of the dose engine by approximating the dose in every voxel with multidimensional polynomials. This Polynomial Chaos (PC) model can be built in an automated fashion relatively cheaply and subsequently it can be used to perform comprehensive robustness analysis. We adapted PC to provide among others the expected dose, the dose variance, accurate probability distribution of dose-volume histogram (DVH) metrics (e.g. minimum tumor or maximum organ dose), exact bandwidths of DVHs, and to separate the effects of random and systematic errors. We present the outcome of our verification experiments based on 6 head-and-neck (HN) patients, and exemplify the usefulness of PCE by comparing a robust and a non-robust treatment plan for a selected HN case. The results suggest that PCE is highly valuable for both research and clinical applications. PMID:27227661

  15. Preoperative assessment tool for the planning of inframammary incision and implant profile in breast augmentation.

    PubMed

    Atiyeh, Bishara S; Dibo, Saad A; Nader, Marie; Papazian, Nazareth J

    2014-10-01

    When using the inframammary access incision for breast augmentation, careful planning is critical to allow the surgeon to set the inframammary fold (IMF) at the most optimal position, minimize scar visibility, and mitigate the main disadvantage of this approach. Current popular evaluation systems for breast augmentation include the High Five and Randquist systems and they base their calculations on inconsistent variables like skin stretch measurements. We propose a simple method that is not dependent on skin stretch measurements to properly determine implant size, profile, and position of the inframammary fold. Excluding digital scans and computer-based systems that are not universally available, the proposed simplified assessment tool was compared to the two most popular manual measuring tools (High Five and Randquist). Twenty-five female volunteers were included in the study. The projected IMF positions over the midsternal line for each measuring tool were recorded on each patient and the sternal notch (SN) to projected IMF distance SN-IMF1 (simplified evaluation system), SN-IMF2 (High Five System), and SN-IMF3 (Randquist system) were compared. The anticipated new IMF position is determined based on the vertical implant dimension and not on breast base width. For most subjects, the differences between the three evaluation systems were minimal. The proposed breast measurement tool constitutes a new, much simpler, and practical method that proved to be successful in our hands. PMID:25060928

  16. Surgical Fixation of Sternal Fractures: Preoperative Planning and a Safe Surgical Technique Using Locked Titanium Plates and Depth Limited Drilling

    PubMed Central

    Schulz-Drost, Stefan; Oppel, Pascal; Grupp, Sina; Schmitt, Sonja; Carbon, Roman Th.; Mauerer, Andreas; Hennig, Friedrich F.; Buder, Thomas

    2015-01-01

    Different ways to stabilize a sternal fracture are described in literature. Respecting different mechanisms of trauma such as the direct impact to the anterior chest wall or the flexion-compression injury of the trunk, there is a need to retain each sternal fragment in the correct position while neutralizing shearing forces to the sternum. Anterior sternal plating provides the best stability and is therefore increasingly used in most cases. However, many surgeons are reluctant to perform sternal osteosynthesis due to possible complications such as difficulties in preoperative planning, severe injuries to mediastinal organs, or failure of the performed method. This manuscript describes one possible safe way to stabilize different types of sternal fractures in a step by step guidance for anterior sternal plating using low profile locking titanium plates. Before surgical treatment, a detailed survey of the patient and a three dimensional reconstructed computed tomography is taken out to get detailed information of the fracture’s morphology. The surgical approach is usually a midline incision. Its position can be described by measuring the distance from upper sternal edge to the fracture and its length can be approximated by the summation of 60 mm for the basis incision, the thickness of presternal soft tissue and the greatest distance between the fragments in case of multiple fractures. Performing subperiosteal dissection along the sternum while reducing the fracture, using depth limited drilling, and fixing the plates prevents injuries to mediastinal organs and vessels. Transverse fractures and oblique fractures at the corpus sterni are plated longitudinally, whereas oblique fractures of manubrium, sternocostal separation and any longitudinally fracture needs to be stabilized by a transverse plate from rib to sternum to rib. Usually the high convenience of a patient is seen during follow up as well as a precise reconstruction of the sternal morphology. PMID

  17. Preoperative transcutaneous electrical nerve stimulation for localizing superficial nerve paths.

    PubMed

    Natori, Yuhei; Yoshizawa, Hidekazu; Mizuno, Hiroshi; Hayashi, Ayato

    2015-12-01

    During surgery, peripheral nerves are often seen to follow unpredictable paths because of previous surgeries and/or compression caused by a tumor. Iatrogenic nerve injury is a serious complication that must be avoided, and preoperative evaluation of nerve paths is important for preventing it. In this study, transcutaneous electrical nerve stimulation (TENS) was used for an in-depth analysis of peripheral nerve paths. This study included 27 patients who underwent the TENS procedure to evaluate the peripheral nerve path (17 males and 10 females; mean age: 59.9 years, range: 18-83 years) of each patient preoperatively. An electrode pen coupled to an electrical nerve stimulator was used for superficial nerve mapping. The TENS procedure was performed on patients' major peripheral nerves that passed close to the surgical field of tumor resection or trauma surgery, and intraoperative damage to those nerves was apprehensive. The paths of the target nerve were detected in most patients preoperatively. The nerve paths of 26 patients were precisely under the markings drawn preoperatively. The nerve path of one patient substantially differed from the preoperative markings with numbness at the surgical region. During surgery, the nerve paths could be accurately mapped preoperatively using the TENS procedure as confirmed by direct visualization of the nerve. This stimulation device is easy to use and offers highly accurate mapping of nerves for surgical planning without major complications. The authors conclude that TENS is a useful tool for noninvasive nerve localization and makes tumor resection a safe and smooth procedure. PMID:26420473

  18. Can radiation therapy treatment planning system accurately predict surface doses in postmastectomy radiation therapy patients?

    SciTech Connect

    Wong, Sharon; Back, Michael; Tan, Poh Wee; Lee, Khai Mun; Baggarley, Shaun; Lu, Jaide Jay

    2012-07-01

    Skin doses have been an important factor in the dose prescription for breast radiotherapy. Recent advances in radiotherapy treatment techniques, such as intensity-modulated radiation therapy (IMRT) and new treatment schemes such as hypofractionated breast therapy have made the precise determination of the surface dose necessary. Detailed information of the dose at various depths of the skin is also critical in designing new treatment strategies. The purpose of this work was to assess the accuracy of surface dose calculation by a clinically used treatment planning system and those measured by thermoluminescence dosimeters (TLDs) in a customized chest wall phantom. This study involved the construction of a chest wall phantom for skin dose assessment. Seven TLDs were distributed throughout each right chest wall phantom to give adequate representation of measured radiation doses. Point doses from the CMS Xio Registered-Sign treatment planning system (TPS) were calculated for each relevant TLD positions and results correlated. There were no significant difference between measured absorbed dose by TLD and calculated doses by the TPS (p > 0.05 (1-tailed). Dose accuracy of up to 2.21% was found. The deviations from the calculated absorbed doses were overall larger (3.4%) when wedges and bolus were used. 3D radiotherapy TPS is a useful and accurate tool to assess the accuracy of surface dose. Our studies have shown that radiation treatment accuracy expressed as a comparison between calculated doses (by TPS) and measured doses (by TLD dosimetry) can be accurately predicted for tangential treatment of the chest wall after mastectomy.

  19. Preoperative Laboratory Testing.

    PubMed

    Bock, Matthias; Fritsch, Gerhard; Hepner, David L

    2016-03-01

    Routine preoperative testing is not cost-effective, because it is unlikely to identify significant abnormalities. Abnormal findings from routine testing are more likely to be false positive, are costly to pursue, introduce a new risk, increase the patient's anxiety, and are inconvenient to the patient. Abnormal findings rarely alter the surgical or anesthetic plan, and there is usually no association between perioperative complications and abnormal laboratory results. Incidental findings and false positive results may lead to increased hospital visits and admissions. Preoperative testing needs to be done based on a targeted history and physical examination and the type of surgery. PMID:26927738

  20. The Preoperative Neurological Evaluation

    PubMed Central

    Probasco, John; Sahin, Bogachan; Tran, Tung; Chung, Tae Hwan; Rosenthal, Liana Shapiro; Mari, Zoltan; Levy, Michael

    2013-01-01

    Neurological diseases are prevalent in the general population, and the neurohospitalist has an important role to play in the preoperative planning for patients with and at risk for developing neurological disease. The neurohospitalist can provide patients and their families as well as anesthesiologists, surgeons, hospitalists, and other providers guidance in particular to the patient’s neurological disease and those he or she is at risk for. Here we present considerations and guidance for the neurohospitalist providing preoperative consultation for the neurological patient with or at risk of disturbances of consciousness, cerebrovascular and carotid disease, epilepsy, neuromuscular disease, and Parkinson disease. PMID:24198903

  1. Reconstruction of applicator positions from multiple-view images for accurate superficial hyperthermia treatment planning

    NASA Astrophysics Data System (ADS)

    Drizdal, T.; Paulides, M. M.; Linthorst, M.; van Rhoon, G. C.

    2012-05-01

    In the current clinical practice, prior to superficial hyperthermia treatments (HT), temperature probes are placed in tissue to document a thermal dose. To investigate whether the painful procedure of catheter placement can be replaced by superficial HT planning, we study if the specific absorption rate (SAR) coverage is predictive for treatment outcome. An absolute requirement for such a study is the accurate reconstruction of the applicator setup. The purpose of this study was to investigate the feasibility of the applicator setup reconstruction from multiple-view images. The accuracy of the multiple-view reconstruction method has been assessed for two experimental setups using six lucite cone applicators (LCAs) representing the largest array applied at our clinic and also the most difficult scenario for the reconstruction. For the two experimental setups and 112 distances, the mean difference between photogrametry reconstructed and manually measured distances was 0.25 ± 0.79 mm (mean±1 standard deviation). By a parameter study of translation T (mm) and rotation R (°) of LCAs, we showed that these inaccuracies are clinically acceptable, i.e. they are either from ±1.02 mm error in translation or ±0.48° in rotation, or combinations expressed by 4.35R2 + 0.97T2 = 1. We anticipate that such small errors will not have a relevant influence on the SAR distribution in the treated region. The clinical applicability of the procedure is shown on a patient with a breast cancer recurrence treated with reirradiation plus superficial hyperthermia using the six-LCA array. The total reconstruction procedure of six LCAs from a set of ten photos currently takes around 1.5 h. We conclude that the reconstruction of superficial HT setup from multiple-view images is feasible and only minor errors are found that will have a negligible influence on treatment planning quality.

  2. Development of a geometrically accurate imaging protocol at 3 Tesla MRI for stereotactic radiosurgery treatment planning

    NASA Astrophysics Data System (ADS)

    Zhang, B.; MacFadden, D.; Damyanovich, A. Z.; Rieker, M.; Stainsby, J.; Bernstein, M.; Jaffray, D. A.; Mikulis, D.; Ménard, C.

    2010-11-01

    The purpose of this study is to develop a geometrically accurate imaging protocol at 3 T magnetic resonance imaging (MRI) for stereotactic radiosurgery (SRS) treatment planning. In order to achieve this purpose, a methodology is developed to investigate the geometric accuracy and stability of 3 T MRI for SRS in phantom and patient evaluations. Forty patients were enrolled on a prospective clinical trial. After frame placement prior to SRS, each patient underwent 3 T MRI after 1.5 T MRI and CT. MR imaging protocols included a T1-weighted gradient echo sequence and a T2-weighted spin echo sequence. Phantom imaging was performed on 3 T prior to patient imaging using the same set-up and imaging protocols. Geometric accuracy in patients and phantoms yielded comparable results for external fiducial reference deviations and internal landmarks between 3 T and 1.5 T MRI (mean <=0.6 mm; standard deviation <=0.3 mm). Mean stereotactic reference deviations between phantoms and patients correlated well (T1: R = 0.79; T2: R = 0.84). Statistical process control analysis on phantom QA data demonstrated the stability of our SRS imaging protocols, where the geometric accuracy of the 3 T SRS imaging protocol is operating within the appropriate tolerance. Our data provide evidence supporting the spatial validity of 3 T MRI for targeting SRS under imaging conditions investigated. We have developed a systematic approach to achieve confidence on the geometric integrity of a given imaging system/technique for clinical integration in SRS application.

  3. Preoperative Planning of Virtual Osteotomies Followed by Fabrication of Patient Specific Reconstruction Plate for Secondary Correction and Fixation of Displaced Bilateral Mandibular Body Fracture.

    PubMed

    Thor, Andreas

    2016-06-01

    This paper describes the course of treatment of a severely diplaced bilateral mandibular body fracture, where the first osteosynthesis failed. The subject developed an open bite due to a posterior rotation of the distal part of the mandible and anterior rotation of the proximal parts of the mandible. This situation was evaluated with CBCT and the facial skeleton was segmented using computer software. Correct occlusion was virtually established by bilateral virtual osteotomies in the fracture areas of the mandible. After segmentation, the mandible was virtually rotated back into position and the open bite was closed. A patient specific mandibular reconstruction plate was outlined and fabricated from the new virtual situation and the plate was thereafter installed utilizing the preoperative plan. Osteotomy- and drill-guides was used and thus simplified the surgery resulting in uneventful healing. Virtual planning and patient specific implants and guides were valuable in this case of secondary reconstructive trauma surgery. PMID:27162581

  4. Indirect assessment of stifle angle for improved accuracy of preoperative planning of tibial osteotomy procedures in dogs.

    PubMed

    Barnes, D C; Owen, M R

    2015-07-25

    To assess reliability of the mechanical axes stifle angle in dogs positioned for radiography with a neutral stifle (neutral stifle angle (nSA)). To investigate radiographic landmarks for assessment of nSA from a collimated radiographic view. One hundred radiographs were taken of normal stifles belonging to 55 skeletally mature medium and large breed dogs, positioned using a repeatable protocol. Radiographs were widely collimated to include the femoral head and the talus. The angle of Blumensaat's line through the intercondylar fossa relative to the Mechanical Axis of the femur (intercondylar fossa angle, IFA), the angle of inclination of a tibial crest tangent line relative to the Mechanical Axis of the tibia (tibial crest angle, TCA) and the tibial plateau angle (TPA) were recorded. Mean nSA was 133.5°. Mean IFA was 155.5°. TCA had a mean of 6.7°. Estimates for nSA were calculated using mean IFA combined with mean TCA (enSA1), mean TPA (enSA2) and the mechanical axis of the tibia (enSA3). Mean percentage error relative was 2.99 per cent for enSA1, 2.82 per cent for enSA2, 1.67 per cent for enSA3. Blumensaat's line provides a consistent radiological feature for assessment of nSA. Assessment of nSA and correction for values varying from 135° may allow more consistent and accurate measurement of patellar tendon angle for presurgical planning. PMID:26187631

  5. The Use of a 3D Printer in Pre-operative Planning for a Patient Requiring Acetabular Reconstructive Surgery

    PubMed Central

    Duncan, James M; Nahas, Samuel; Akhtar, Kashif; Daurka, Jasvinder

    2015-01-01

    Introduction: Surgical management of acetabular fractures is often highly complex, and a successful outcome depends upon an appreciation of the fracture pattern and the most appropriate approach to reduce and hold it. Currently, computed tomography (CT) images are used in conjunction with plain x-rays to identify the main fracture components and their spatial relationship to one another, and as such surgeons still have to make decisions based upon their ability to visualise the fracture from the images available. 3D printers have now become widely available and inexpensive, and can be used to rapidly produce life-size models based on CT scans of an individual patient. The availability of patient specific, accurate and detailed models of complex acetabular fractures can aid planning of surgical management on a patient specific basis. Case Report: This report describes the use of a 3D printer to create a life-size model reconstruction of the pelvis of a 48 year old male patient who sustained a left sided associated both column acetabular fracture following a motorbike accident in the Sahara Desert. The model allowed visualisation of the multiple fracture fragments and their relative displacements. The tactile feedback allowed assessment of the different fracture fragments. The relative displacement of the quadrilateral plate and posterior column fragments could be assessed and the surgeon felt that these would be amenable to reduction from an ilioinguinal approach. An anatomic reduction was achieved and was held with the application of a pelvic brim plate with 2 screws lagging the posterior column/quadrilateral plate fragment. Conclusion: There are previous examples of 3D models being used in orthopaedic surgery through the use of rapid prototyping, however this method is usually expensive and time consuming. Advances in 3D printer technology offer surgeons a number of advantages when treating these complex fractures. With the ever-increasing economy, ease of use and

  6. [Understanding and implementing the Party's policies on family planning accurately in an all-around way].

    PubMed

    Liang, J; Peng, Z

    1984-05-29

    Recently, the Party's Central Committee held numerous meetings to study the problem of family planning. The main goal of these meetings was to find a correct family planning policy, which should be based on common sense, support from the people, and reasonable work from the cadres. Family planning policies and regulations should be realistic and creative. In the implementation of policies, different methods should be adopted for varied situations, and there should also be appropriate guiding principles for different categories. To cope with a new situation, creative methods and approaches should be chosen in order to implement the family planning policy. The correct method will ensure complete implementation of the policy. In family planning work, the first step is the improvement of ideological education, so that the people may have a correct understanding of the need for family planning. In the technical management work of family planning, a constant improvement in the quality of service should be the goal. Through practical working experience in family planning, some rules and regulations will be found, and they should be used to promote the management level and the level of family planning work in general. PMID:12159337

  7. [The preoperative anaesthetic visit].

    PubMed

    Harms, Christoph; Kindler, Christoph H

    2009-07-01

    Anaesthetists often visit their patients in exceptional situations characterised by preoperative anxiety or distress. Therefore, even brief contact with the patient can be considered intense and meaningful. The initial preoperative anaesthetic visit is the beginning of the relationship between patient and anaesthetist, and should help to explain the planned anaesthetic technique. Preoperative anaesthetic visits are intense and last for 20 minutes on average. They should assert a professional approach to the patient's emotions, particularly to preoperative anxiety, and a structured and clear collection of information including the past history of the patient. These visits should also provide information about the anaesthesia itself and instructions for the patient with respect to the perioperative period. Communication about the side effects and risks of anaesthetic techniques, and the discussion of potential alternatives are mandatory. Worldwide, courts of law increasingly require a documented discussion between the anaesthetist and patient based on risk-benefit evidence. Today, there is in general a shift away from decisions made solely by physicians, reflecting an increased respect for the autonomy of the patient towards a model of shared decision-making and informed choice. Ideally, the preoperative visit follows the four key habits of highly effective clinicians, i.e., to rapidly establish a rapport with the patient and provide an agenda for the visit, to explore the patient's perspectives and expectations, to demonstrate empathy, and to focus on the end of the visit with providing information and including the patient in the decision-making process. Visits are then concluded upon obtaining informed consent from the patient. PMID:19565444

  8. Three-dimensional reconstructed computed tomography-magnetic resonance fusion image-based preoperative planning for surgical procedures for spinal lipoma or tethered spinal cord after myelomeningocele repair.

    PubMed

    Bamba, Yohei; Nonaka, Masahiro; Nakajima, Shin; Yamasaki, Mami

    2011-01-01

    Surgical procedures for spinal lipoma or tethered spinal cord after myelomeningocele (MMC) repair are often difficult and complicated, because the anatomical structures can be deformed in complex and unpredictable ways. Imaging helps the surgeon understand the patient's spinal anatomy. Whereas two-dimensional images provide only limited information for surgical planning, three-dimensional (3D) reconstructed computed tomography (CT)-magnetic resonance (MR) fusion images produce clearer representations of the spinal regions. Here we describe simple and quick methods for obtaining 3D reconstructed CT-MR fusion images for preoperative planning of surgical procedures using the iPlan(®) cranial (BrainLAB AG, Feldkirchen, Germany) neuronavigation software. 3D CT images of the vertebral bone were combined with heavily T(2)-weighted MR images of the spinal cord, lipoma, cerebrospinal fluid (CSF) space, and nerve root through a process of fusion, segmentation, and reconstruction of the 3D images. We also used our procedure called "Image Overlay" to directly project the 3D reconstructed image onto the body surface using an LED projector. The final reconstructed 3D images took 10-30 minutes to obtain, and provided the surgeon with a representation of the individual pathological structures, so enabled the design of effective surgical plans, even in patients with bony deformity such as scoliosis. None of the 19 patients treated based on our 3D reconstruction method has had neurological complications, except for CSF leakage. This 3D reconstructed imaging method, combined with Image Overlay, improves the visual understanding of complicated surgical situations, and should improve surgical efficiency and outcome. PMID:21613771

  9. The development and verification of a highly accurate collision prediction model for automated noncoplanar plan delivery

    SciTech Connect

    Yu, Victoria Y.; Tran, Angelia; Nguyen, Dan; Cao, Minsong; Ruan, Dan; Low, Daniel A.; Sheng, Ke

    2015-11-15

    Purpose: Significant dosimetric benefits had been previously demonstrated in highly noncoplanar treatment plans. In this study, the authors developed and verified an individualized collision model for the purpose of delivering highly noncoplanar radiotherapy and tested the feasibility of total delivery automation with Varian TrueBeam developer mode. Methods: A hand-held 3D scanner was used to capture the surfaces of an anthropomorphic phantom and a human subject, which were positioned with a computer-aided design model of a TrueBeam machine to create a detailed virtual geometrical collision model. The collision model included gantry, collimator, and couch motion degrees of freedom. The accuracy of the 3D scanner was validated by scanning a rigid cubical phantom with known dimensions. The collision model was then validated by generating 300 linear accelerator orientations corresponding to 300 gantry-to-couch and gantry-to-phantom distances, and comparing the corresponding distance measurements to their corresponding models. The linear accelerator orientations reflected uniformly sampled noncoplanar beam angles to the head, lung, and prostate. The distance discrepancies between measurements on the physical and virtual systems were used to estimate treatment-site-specific safety buffer distances with 0.1%, 0.01%, and 0.001% probability of collision between the gantry and couch or phantom. Plans containing 20 noncoplanar beams to the brain, lung, and prostate optimized via an in-house noncoplanar radiotherapy platform were converted into XML script for automated delivery and the entire delivery was recorded and timed to demonstrate the feasibility of automated delivery. Results: The 3D scanner measured the dimension of the 14 cm cubic phantom within 0.5 mm. The maximal absolute discrepancy between machine and model measurements for gantry-to-couch and gantry-to-phantom was 0.95 and 2.97 cm, respectively. The reduced accuracy of gantry-to-phantom measurements was

  10. Toward optimizing patient-specific IMRT QA techniques in the accurate detection of dosimetrically acceptable and unacceptable patient plans

    SciTech Connect

    McKenzie, Elizabeth M.; Balter, Peter A.; Stingo, Francesco C.; Jones, Jimmy; Followill, David S.; Kry, Stephen F.

    2014-12-15

    was no significant difference in the performance of any device between gamma criteria of 2%/2 mm, 3%/3 mm, and 5%/3 mm. Finally, optimal cutoffs (e.g., percent of pixels passing gamma) were determined for each device and while clinical practice commonly uses a threshold of 90% of pixels passing for most cases, these results showed variability in the optimal cutoff among devices. Conclusions: IMRT QA devices have differences in their ability to accurately detect dosimetrically acceptable and unacceptable plans. Field-by-field analysis with a MapCheck device and use of the MapCheck with a MapPhan phantom while delivering at planned rotational gantry angles resulted in a significantly poorer ability to accurately sort acceptable and unacceptable plans compared with the other techniques examined. Patient-specific IMRT QA techniques in general should be thoroughly evaluated for their ability to correctly differentiate acceptable and unacceptable plans. Additionally, optimal agreement thresholds should be identified and used as common clinical thresholds typically worked very poorly to identify unacceptable plans.

  11. A plan for accurate estimation of daily area-mean rainfall during the CaPE experiment

    NASA Technical Reports Server (NTRS)

    Duchon, Claude E.

    1992-01-01

    The Convection and Precipitation/Electrification (CaPE) experiment took place in east central Florida from 8 July to 18 August, 1991. There were five research themes associated with CaPE. In broad terms they are: investigation of the evolution of the electric field in convective clouds, determination of meteorological and electrical conditions associated with lightning, development of mesoscale numerical forecasts (2-12 hr) and nowcasts (less than 2 hr) of convective initiation and remote estimation of rainfall. It is the last theme coupled with numerous raingage and streamgage measurements, satellite and aircraft remote sensing, radiosondes and other meteorological measurements in the atmospheric boundary layer that provide the basis for determining the hydrologic cycle for the CaPE experiment area. The largest component of the hydrologic cycle in this region is rainfall. An accurate determination of daily area-mean rainfall is important in correctly modeling its apportionment into runoff, infiltration and evapotranspiration. In order to achieve this goal a research plan was devised and initial analysis begun. The overall research plan is discussed with special emphasis placed on the adjustment of radar rainfall estimates to raingage rainfall.

  12. Considerations and Protocols in Virtual Surgical Planning of Reconstructive Surgery for More Accurate and Esthetic Neomandible with Deep Circumflex Iliac Artery Free Flap

    PubMed Central

    Kim, Nam-Kyoo; Kim, Hyun Young; Kim, Hyung Jun; Cha, In-Ho; Nam, Woong

    2014-01-01

    Purpose: The reconstruction of mandibular defects poses many difficulties due to the unique, complex shape of the mandible and the temporomandibular joints. With development of microvascular anastomosis, free tissue transplantation techniques, such as deep circumflex iliac artery (DCIA) flap and fibular free flap (FFF), were developed. The DCIA offers good quality and quantity of bone tissue for mandibular segmental defect and implant for dental rehabilitation. Virtual surgical planning (VSP) and stereolithography-guided osteotomy are currently successfully applied in three-dimensional mandibular reconstruction, but most use FFF. There are only a few articles on reconstruction with the DCIA that assess the postoperative results. Methods: Three patients admitted during a five month period (April of 2013 to August of 2013) underwent resection of mandible and DCIA musculo-osseous reconstruction using a VSP and stereolithographic modeling and assessment of outcomes included technical accuracy, esthetic contour, and functional outcomes. Results: This technique yielded iliac bone segment with excellent apposition and duplication of the preoperative plan. Flap survival was 100 percent and all patients maintained preoperative occlusion and contour. Conclusion: Based on our experience, we offer considerations and logically consistent protocols by classification of mandibular defects, and demonstrate the benefits in VSP and stereolithographic modeling of mandibular reconstructive surgery with DCIA flap. PMID:27489828

  13. A homotopy-based sparse representation for fast and accurate shape prior modeling in liver surgical planning.

    PubMed

    Wang, Guotai; Zhang, Shaoting; Xie, Hongzhi; Metaxas, Dimitris N; Gu, Lixu

    2015-01-01

    Shape prior plays an important role in accurate and robust liver segmentation. However, liver shapes have complex variations and accurate modeling of liver shapes is challenging. Using large-scale training data can improve the accuracy but it limits the computational efficiency. In order to obtain accurate liver shape priors without sacrificing the efficiency when dealing with large-scale training data, we investigate effective and scalable shape prior modeling method that is more applicable in clinical liver surgical planning system. We employed the Sparse Shape Composition (SSC) to represent liver shapes by an optimized sparse combination of shapes in the repository, without any assumptions on parametric distributions of liver shapes. To leverage large-scale training data and improve the computational efficiency of SSC, we also introduced a homotopy-based method to quickly solve the L1-norm optimization problem in SSC. This method takes advantage of the sparsity of shape modeling, and solves the original optimization problem in SSC by continuously transforming it into a series of simplified problems whose solution is fast to compute. When new training shapes arrive gradually, the homotopy strategy updates the optimal solution on the fly and avoids re-computing it from scratch. Experiments showed that SSC had a high accuracy and efficiency in dealing with complex liver shape variations, excluding gross errors and preserving local details on the input liver shape. The homotopy-based SSC had a high computational efficiency, and its runtime increased very slowly when repository's capacity and vertex number rose to a large degree. When repository's capacity was 10,000, with 2000 vertices on each shape, homotopy method cost merely about 11.29 s to solve the optimization problem in SSC, nearly 2000 times faster than interior point method. The dice similarity coefficient (DSC), average symmetric surface distance (ASD), and maximum symmetric surface distance measurement

  14. Preoperative Imaging for Clinical Staging Prior to Radical Cystectomy.

    PubMed

    Hugen, Cory M; Duddalwar, Vinay; Daneshmand, Siamak

    2016-09-01

    The importance of patient selection for quality outcomes following radical cystectomy is critical. Clinical staging is one of the key elements necessary for patient selection, and staging relies on accurate preoperative imaging. Many imaging modalities are available and have been utilized for preoperative staging with published operating characteristics. In this update, we review recently published literature for advances in preoperative imaging prior to radical cystectomy. PMID:27432379

  15. Three-Dimensional Surface Imaging and the Continuous Evolution of Preoperative and Postoperative Assessment in Rhinoplasty.

    PubMed

    Lekakis, Garyfalia; Claes, Peter; Hamilton, Grant S; Hellings, P W

    2016-02-01

    During the preoperative assessment in rhinoplasty, the surgeon takes a thorough history, performs a complete examination by assessing functional and aesthetic aspects of the nose, obtains a clear understanding of the patient's wishes, conducts facial analysis based on standardized photography, and communicates to the patient the goals and pitfalls of surgery. Computer imaging or morphing of the preoperative pictures of the nose has drawn a lot of interest in the last decade, and it is a sign of evolution of the preoperative consultation. Technological advances, also in the context of rhinoplasty, have led to the development of three-dimensional (3D) imaging techniques, and have completely revolutionized the way that surgeons manage their patients preoperatively and evaluate postoperative results today. The accurate 3D surface imaging aids the surgeon to communicate with the patient adequately before surgery, to set an appropriate surgical plan, and to measure the shape and volume changes of the patient's nose that result from the intervention. The present review provides an analysis on the current knowledge of 3D surface imaging in rhinoplasty derived from the literature, and highlights future directions of preoperative and postoperative assessment in the field. PMID:26862969

  16. [Present status of preoperative staging and contemplation on preoperative precision staging for gastric cancer].

    PubMed

    Zhu, Zhenggang

    2016-02-25

    The aim of the preoperative staging of gastric cancer was to evaluate the depth of tumor infiltration (T-stage), the extent or number of metastasized lymph nodes (N-stage), and distant metastasis (M-stage) before surgery, to develop an optimal therapeutic scheme for the patients with gastric cancer. Traditional methods of preoperative staging for gastric cancer are usually imaging diagnostic techniques, such as endoscopic ultrasonography (EUS), CT scan, magnetic resonance imaging (MRI) and laparoscopic exploration. At present, the accuracy of preoperative TNM staging of gastric cancer can generally reach 70% to 85% with significant clinical benefit. The accurate preoperative staging for cancer patients can have a major role in determining the final clinical outcome and in predicting the prognosis. According to the concept of "precision medicine", to achieve "preoperative precision staging of gastric cancer", the application of imaging diagnostic techniques must be combined with the analysis of individual genetic information or tumor molecular pathological classification, which should be based on research of the disease genomics, proteomics and metabolomics. In this article, we provide a review of results on preoperative staging of gastric cancer in recent years, and we also discuss how to think about the "preoperative precision staging of gastric cancer", with special emphasis on the potential of molecular imaging techniques, circulating tumor cells (CTCs) or circulating tumor DNA (ctDNA), molecular targets for tumor targeting therapy and molecular pathological classification, etc. in judging bio-molecular behavior of gastric cancer before surgery. PMID:26831874

  17. Office-based rapid prototyping in orthopedic surgery: a novel planning technique and review of the literature.

    PubMed

    Schwartz, Adam; Money, Kyle; Spangehl, Mark; Hattrup, Steven; Claridge, Richard J; Beauchamp, Christopher

    2015-01-01

    Three-dimensional (3-D) prototyping, based on high-quality axial images, may allow for more accurate and extensive preoperative planning and may even allow surgeons to perform procedures as part of preoperative preparation. In this article, we describe 7 cases of complex orthopedic disorders that were surgically treated after preoperative planning that was based on both industry-provided models and use of our in-house 3-D printer. Commercially available 3-D printers allow for rapid in-office production of a high-quality realistic prototype at relatively low per-case cost. Using this technique, surgeons can assess the accuracy of their original surgical plans and, if necessary, correct them preoperatively. The ability to "perform surgery preoperatively" adds another element to surgeons' perceptions of the potential issues that may arise. PMID:25566552

  18. Avoiding Unnecessary Preoperative Testing.

    PubMed

    Rusk, Matthew H

    2016-09-01

    Given the low-risk nature of cataract surgery, no preoperative testing is indicated unless the patient needs it for another reason. Although electrocardiograms may have a role in preoperative testing in patients at high risk of cardiovascular disease, or if the procedure carries with it significant operative risks, they are often unnecessary. Urinalysis and coagulation studies not should be routine because they have not shown any value in predicting complications. Although these tests are not individually expensive, the aggregate cost is substantial. As good stewards of the medical system, physicians need to use these tests more judiciously. PMID:27542420

  19. How accurately can current, planned and proposed InSAR missions measure slow, long-wavelength tectonic strain? (Invited)

    NASA Astrophysics Data System (ADS)

    Wright, T. J.; Garthwaite, M.; Jung, H.; Shepherd, A.

    2010-12-01

    Since the launch of ERS-1 in 1991, InSAR has been widely used to measure large deformation events such as earthquakes or volcanic eruptions. In the last decade, small strains accumulating around locked crustal faults and dormant volcanic edifices have also been measured, in certain favourable conditions. In this presentation, we discuss the accuracy of current, planned and proposed InSAR missions. We quantify the main contributions to the error budget of a single interferogram at different spatial scales: atmospheric and orbital errors dominate at long wavelengths (tens of kilometres), and errors from system noise and surface incoherence at short spatial scales (tens of metres). We show that the optimum method for combining multiple interferograms to measure the average line-of-sight (LOS) deformation rate is via a weighted linear inversion of a connected network of short-interval interferograms. The LOS accuracy is strongly dependent on the mission length and satellite revisit time, as well as the spatial length scale. For example, to obtain an LOS accuracy of 1 mm/yr over 100 km requires 5 years of observation with a 13-day repeat, or 7 years for a 35-day repeat. We assess the ability of current (ERS/Envisat), planned (Sentinel-1), and proposed (SuperSAR, DesDYNI) satellite missions to measure long wavelength tectonic strain by estimating the proportion of global straining areas (as defined by the Global Strain Rate Map) where the strain rates are higher than the measurement error. The results highlight the importance of obtaining measurements in three dimensions in order to monitor all actively deforming regions. Of the planned/proposed missions, only SuperSAR (submitted to ESA’s Earth Explorer 8 call) has the ability to achieve 1 mm/yr accuracy over 100 km in all three dimensions after 5 years of observation. This is sufficient to map strain accumulating around faults that are responsible for 95% of damaging onshore earthquakes.

  20. Reliability of Task-Based fMRI for Preoperative Planning: A Test-Retest Study in Brain Tumor Patients and Healthy Controls

    PubMed Central

    Morrison, Melanie A.; Churchill, Nathan W.; Cusimano, Michael D.; Schweizer, Tom A.; Das, Sunit; Graham, Simon J.

    2016-01-01

    Background Functional magnetic resonance imaging (fMRI) continues to develop as a clinical tool for patients with brain cancer, offering data that may directly influence surgical decisions. Unfortunately, routine integration of preoperative fMRI has been limited by concerns about reliability. Many pertinent studies have been undertaken involving healthy controls, but work involving brain tumor patients has been limited. To develop fMRI fully as a clinical tool, it will be critical to examine these reliability issues among patients with brain tumors. The present work is the first to extensively characterize differences in activation map quality between brain tumor patients and healthy controls, including the effects of tumor grade and the chosen behavioral testing paradigm on reliability outcomes. Method Test-retest data were collected for a group of low-grade (n = 6) and high-grade glioma (n = 6) patients, and for matched healthy controls (n = 12), who performed motor and language tasks during a single fMRI session. Reliability was characterized by the spatial overlap and displacement of brain activity clusters, BOLD signal stability, and the laterality index. Significance testing was performed to assess differences in reliability between the patients and controls, and low-grade and high-grade patients; as well as between different fMRI testing paradigms. Results There were few significant differences in fMRI reliability measures between patients and controls. Reliability was significantly lower when comparing high-grade tumor patients to controls, or to low-grade tumor patients. The motor task produced more reliable activation patterns than the language tasks, as did the rhyming task in comparison to the phonemic fluency task. Conclusion In low-grade glioma patients, fMRI data are as reliable as healthy control subjects. For high-grade glioma patients, further investigation is required to determine the underlying causes of reduced reliability. To maximize

  1. Does preoperative rehabilitation for patients planning to undergo joint replacement surgery improve outcomes? A systematic review and meta-analysis of randomised controlled trials

    PubMed Central

    Wang, Li; Lee, Myeongjong; Zhang, Zhe; Moodie, Jessica; Cheng, Davy; Martin, Janet

    2016-01-01

    Objectives The clinical impact of preoperative physiotherapy on recovery after joint replacement remains controversial. This systematic review aimed to assess the clinical impact of prehabilitation before joint replacement. Design We searched PubMed, Embase and Cochrane CENTRAL up to November 2015 for randomised controlled trials comparing prehabilitation versus no prehabilitation before joint replacement surgery. Postoperative pain and function scores were converted to Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function subscales (0–100, high scores indicate worse outcome). Random effects meta-analysis was performed to calculate weighted mean differences (WMD, 95% CI), subgrouped by hip and knee surgery. Primary and secondary outcomes Postoperative pain and function scores, time to resume activities of daily living, quality of life, length of hospital stay, total cost, patient satisfaction, postoperative complications, any adverse events and discontinuations. Results Of 22 studies (1492 patients), 18 had high risk of bias. Prehabilitation slightly reduced pain scores within 4 weeks postoperatively (WMD −6.1 points, 95% CI −10.6 to −1.6 points, on a scale of 0–100), but differences did not remain beyond 4 weeks. Prehabilitation slightly improved WOMAC function score at 6–8 and 12 weeks (WMD −4.0, 95% CI −7.5 to −0.5), and time to climbing stairs (WMD −1.4 days, 95% CI −1.9 to −0.8 days), toilet use (−0.9 days, 95% CI −1.3 to −0.5 days) and chair use (WMD −1.2 days, 95% CI −1.7 to −0.8 days). Effects were similar for knee and hip surgery. Differences were not found for SF-36 scores, length of stay and total cost. Other outcomes of interest were inadequately reported. Conclusions Existing evidence suggests that prehabilitation may slightly improve early postoperative pain and function among patients undergoing joint replacement; however, effects remain too small and short

  2. Preoperative biliary drainage.

    PubMed

    Saxena, Payal; Kumbhari, Vivek; Zein, Mohamad E L; Khashab, Mouen A

    2015-01-01

    The role of preoperative biliary drainage (PBD) in patients with distal or proximal biliary obstruction secondary to resectable tumors has been a matter for debate. A review of the literature using Medline, Embase and Cochrane databases was undertaken for studies evaluating routes of drainage (endoscopic or percutaneous) and stent types (plastic or metal) in patients with resectable disease. Preoperative biliary drainage is indicated for relief of symptomatic jaundice, cholangitis, patients undergoing neoadjuvant therapy or those patients where surgery may be delayed. Endoscopic methods are preferred over percutaneous methods because of lower complication rates. In patients with proximal biliary obstruction, PBD should be guided by imaging studies to aid in selective biliary cannulation for unilateral drainage in order to reduce the risk of cholangitis in undrained liver segments. PMID:25293587

  3. Preoperative imaging of liver metastases. Comparison of angiography, CT scan, and ultrasonography.

    PubMed Central

    Gunvén, P; Makuuchi, M; Takayasu, K; Moriyama, N; Yamasaki, S; Hasegawa, H

    1985-01-01

    Thirty-one patients with mostly colorectal cancer metastases to the liver had preoperative selective/superselective angiograms (24 cases), computed tomography (CT) [26 cases, mostly enhanced by contrast administered by a peripheral vein (9), the common hepatic artery (9), or the portal vein (5)], and ultrasonography (26 cases). Intraoperative ultrasonography and palpation and examination of the resected specimens revealed 113 tumors. CT detected almost half of the masses smaller than 1 cm, and ultrasonography and angiography about one-third of lesions 1-2 cm in size. Ultrasonography was less powerful for examination of the posterior segment of the liver. CT and ultrasonography placed the tumors into subsegments more accurately than did angiography. Almost 40% of the preoperative plans had to be changed: in two-thirds by extended resections and in one-third by a change from curative to palliative intent. Most changes were due to extrahepatic tumor growth, often within areas screened before surgery. The use of all three imaging modalities for liver metastases is recommended for preoperative planning. PMID:3901943

  4. Reducing the Need for Accurate Stream Flow Forecasting for Water Supply Planning by Augmenting Reservoir Operations with Seawater Desalination and Wastewater Recycling

    NASA Astrophysics Data System (ADS)

    Bhushan, R.; Ng, T. L.

    2014-12-01

    Accurate stream flow forecasts are critical for reservoir operations for water supply planning. As the world urban population increases, the demand for water in cities is also increasing, making accurate forecasts even more important. However, accurate forecasting of stream flows is difficult owing to short- and long-term weather variations. We propose to reduce this need for accurate stream flow forecasts by augmenting reservoir operations with seawater desalination and wastewater recycling. We develop a robust operating policy for the joint operation of the three sources. With the joint model, we tap into the unlimited reserve of seawater through desalination, and make use of local supplies of wastewater through recycling. However, both seawater desalination and recycling are energy intensive and relatively expensive. Reservoir water on the other hand, is generally cheaper but is limited and variable in its availability, increasing the risk of water shortage during extreme climate events. We operate the joint system by optimizing it using a genetic algorithm to maximize water supply reliability and resilience while minimizing vulnerability subject to a budget constraint and for a given stream flow forecast. To compute the total cost of the system, we take into account the pumping cost of transporting reservoir water to its final destination, and the capital and operating costs of desalinating seawater and recycling wastewater. We produce results for different hydro climatic regions based on artificial stream flows we generate using a simple hydrological model and an autoregressive time series model. The artificial flows are generated from precipitation and temperature data from the Canadian Regional Climate model for present and future scenarios. We observe that the joint operation is able to effectively minimize the negative effects of stream flow forecast uncertainty on system performance at an overall cost that is not significantly greater than the cost of a

  5. Which preoperative respiratory evaluation?

    PubMed

    Zraier, S; Haouache, H; Dhonneur, G

    2014-01-01

    The preoperative respiratory evaluation aims at predicting the occurrence of postoperative respiratory complications (PORC), such as: atelectasis, pulmonary infection (bronchitis and pneumonia), acute ventilatory distress, pleural effusion, prolonged mechanical ventilation, exacerbation of chronic respiratory disease and bronchospasm. The incidence of (PORC) all surgeries combined is 6.8%. Individual surgical and anesthetic factors are impacting on the occurrence of PORC. Simple scores, including anamnestic data, clinical examination and some biological parameters were validated to assess the risk of PORC depending on the type of surgery. Data from standard pulmonary function tests (PFT) is of little use to estimate the individual risk of PORC. Most of the time, PFT abnormal parameters only confirm the clinical assessment of the severity of the illness. PFT may however be useful to confirm an improvement in the clinical condition of the patient related to the preoperative preparation. Specialized EFR, including standardized testing efforts are sometimes required in the case of lung reduction surgery. These specialized explorations can predict lung function and post-interventional pulmonary oxygenation and ensure that these are viable. PMID:25168302

  6. Comparison of Preoperative Temporal Bone CT with Intraoperative Findings in Patients with Cholesteatoma

    PubMed Central

    Rogha, Mehrdad; Hashemi, Sayyed Mostafa; Mokhtarinejad, Farhad; Eshaghian, Afrooz; Dadgostar, Alireza

    2014-01-01

    Introduction: Cholesteatoma is traditionally diagnosed by otoscopic examination and treated by surgery. The necessity for imaging in an uncomplicated case is controversial. This study was planned to investigate the usefulness of a preoperative high-resolution computed tomography (HRCT) scan in depicting the status of middle ear structures in the presence of cholesteatoma and also to compare the correspondence between pre- and intraoperative CT findings in patients with cholesteatoma. Materials and Methods: This prospective descriptive study was performed from January 2009 to May 2011 in 36 patients with cholesteatoma who were referred to the Kashani and Al-Zahra Clinics of Otolaryngology. Preoperative high-resolution temporal bone CT scans (axial and coronal views) were carried out and compared with intraoperative findings. Results: Evaluation of 36 patients and their CT scans revealed excellent correlation for sigmoid plate erosion, widening of aditus, and erosion of scutum; good correlation for erosion of malleus and tegmen; moderate correlation for lateral canal fistula (LCF) and erosion of mastoid air cells; and poor correlation for facial nerve dehiscence (FND), incus, and stapes erosion. Conclusion: A preoperative CT scan may be helpful in relation to diagnosis and decision making for surgery in cases of cholesteatoma and ossicular erosion. The CT scan can accurately predict the extent of disease and is helpful for detection of lateral canal fistula, erosions of dural plate, and ossicular erosions. However it is not able to distinguish between cholesteatoma and mucosal disease, facial nerve dehiscency, incus, and stapes erosion. PMID:24505568

  7. Fast and accurate Monte Carlo modeling of a kilovoltage X-ray therapy unit using a photon-source approximation for treatment planning in complex media

    PubMed Central

    Zeinali-Rafsanjani, B.; Mosleh-Shirazi, M. A.; Faghihi, R.; Karbasi, S.; Mosalaei, A.

    2015-01-01

    To accurately recompute dose distributions in chest-wall radiotherapy with 120 kVp kilovoltage X-rays, an MCNP4C Monte Carlo model is presented using a fast method that obviates the need to fully model the tube components. To validate the model, half-value layer (HVL), percentage depth doses (PDDs) and beam profiles were measured. Dose measurements were performed for a more complex situation using thermoluminescence dosimeters (TLDs) placed within a Rando phantom. The measured and computed first and second HVLs were 3.8, 10.3 mm Al and 3.8, 10.6 mm Al, respectively. The differences between measured and calculated PDDs and beam profiles in water were within 2 mm/2% for all data points. In the Rando phantom, differences for majority of data points were within 2%. The proposed model offered an approximately 9500-fold reduced run time compared to the conventional full simulation. The acceptable agreement, based on international criteria, between the simulations and the measurements validates the accuracy of the model for its use in treatment planning and radiobiological modeling studies of superficial therapies including chest-wall irradiation using kilovoltage beam. PMID:26170553

  8. Fast and accurate Monte Carlo modeling of a kilovoltage X-ray therapy unit using a photon-source approximation for treatment planning in complex media.

    PubMed

    Zeinali-Rafsanjani, B; Mosleh-Shirazi, M A; Faghihi, R; Karbasi, S; Mosalaei, A

    2015-01-01

    To accurately recompute dose distributions in chest-wall radiotherapy with 120 kVp kilovoltage X-rays, an MCNP4C Monte Carlo model is presented using a fast method that obviates the need to fully model the tube components. To validate the model, half-value layer (HVL), percentage depth doses (PDDs) and beam profiles were measured. Dose measurements were performed for a more complex situation using thermoluminescence dosimeters (TLDs) placed within a Rando phantom. The measured and computed first and second HVLs were 3.8, 10.3 mm Al and 3.8, 10.6 mm Al, respectively. The differences between measured and calculated PDDs and beam profiles in water were within 2 mm/2% for all data points. In the Rando phantom, differences for majority of data points were within 2%. The proposed model offered an approximately 9500-fold reduced run time compared to the conventional full simulation. The acceptable agreement, based on international criteria, between the simulations and the measurements validates the accuracy of the model for its use in treatment planning and radiobiological modeling studies of superficial therapies including chest-wall irradiation using kilovoltage beam. PMID:26170553

  9. Effectiveness of endoscopic clipping and computed tomography gastroscopy for the preoperative localization of gastric cancer

    PubMed Central

    Jeong, Sang-Ho; Bae, Kyungsoo; Ha, Chang-Youn; Lee, Ok-Jae; Jung, Woon-Tae; Choi, Sang-Kyung; Hong, Soon-Chan; Jung, Eun-Jung; Ju, Young-Tae; Jeong, Chi-Young; Ha, Woo-Song

    2013-01-01

    Purpose Before laparoscopic gastrectomy for gastric cancer can be planned, it is very important to know the precise location of the tumor. The aim of this study was to evaluate 3 methods of predicting the exact location of the tumor: preoperative gastrofibroscopy (GFS), preoperative computed tomography gastroscopy (CT), and intraoperative gastroscopy-guided laparoscopy (Lap). Methods In this study, 15 patients were prospectively identified, and endoscopic clips were preoperatively placed on the proximal 1 cm of the tumor, at the angle on the greater curvature and opposite the angle on the greater curvature. The distances between the pylorus and the proximal tumor clip (PT), the angle clip (PA), the greater curvature clip (PG), and the gastroesophageal junction were measured by preoperative GFS, preoperative CT, intraoperative Lap, and visual inspection (Vis). Results PT, PA, and PG values measured by preoperative GFS differed significantly from the Vis values (P < 0.01). However, preoperative CT measurements of PT, PA, and PG did not differ from the Vis values (P = 0.78, P = 0.48, and P = 0.53, respectively). Intraoperative Lap and Vis PT values differed by only 1.1 cm on an average (P = 0.10), but PA and PG values varied by 1.9 and 3.4 cm, respectively (P = 0.01 for both). Conclusion Endoscopic clipping combined with preoperative CT gastroscopy is more useful than preoperative GFS for preoperatively predicting the location of early gastric cancers and will be helpful for planning laparoscopic gastrectomy. PMID:23396626

  10. [Preoperative fasting guidelines: an update].

    PubMed

    López Muñoz, A C; Busto Aguirreurreta, N; Tomás Braulio, J

    2015-03-01

    Anesthesiology societies have issued various guidelines on preoperative fasting since 1990, not only to decrease the incidence of lung aspiration and anesthetic morbidity, but also to increase patient comfort prior to anesthesia. Some of these societies have been updating their guidelines, as such that, since 2010, we now have 2 evidence-based preoperative fasting guidelines available. In this article, an attempt is made to review these updated guidelines, as well as the current instructions for more controversial patients such as infants, the obese, and a particular type of ophthalmic surgery. PMID:25443866

  11. [Artificial nutrition and preoperative fasting].

    PubMed

    Francq, B; Sohawon, S; Perlot, I; Sekkat, H; Noordally, S O

    2012-01-01

    Preoperative fasting is a currently adopted measure since Mendelson's report pertaining to aspiration pneumonia as a cause of death following general anesthesia. From a metabolic point of view fasting is detrimental because surgery in itself causes a state of hypercatabolism and hyperglycemia as a result of insulinresistance. Preoperative fasting has become almost obsolete in certain elective surgical procedures. In these cases the use of clear liquids is now well established and this paper focuses on the safe use of clear fluids, postoperative insulinresistance, patient comfort and postoperative outcome as well as its effect on the length of stay. PMID:22812052

  12. Preoperative Psychological Preparation of Children

    PubMed Central

    Güleç, Ersel; Özcengiz, Dilek

    2015-01-01

    Surgery and anaesthesia are significant sources of anxiety for children. In the preoperative period, reducing anxiety helps in preventing the negative consequences that may occur after surgery. The predetermined high-risk children in terms of the development of anxiety play an important role in reducing the negative consequences. Recently featured approaches are modelling and coping techniques, although many techniques are used in the preoperative psychological preparation. The use of computer programs in this area may facilitate important achievements, and it needs to support new studies to be performed. PMID:27366525

  13. Preoperative digital mammography imaging in conservative mastectomy and immediate reconstruction

    PubMed Central

    Angrigiani, Claudio; Hammond, Dennis; Nava, Maurizio; Gonzalez, Eduardo; Rostagno, Roman; Gercovich, Gustavo

    2016-01-01

    Background Digital mammography clearly distinguishes gland tissue density from the overlying non-glandular breast tissue coverage, which corresponds to the existing tissue between the skin and the Cooper’s ligaments surrounding the gland (i.e., dermis and subcutaneous fat). Preoperative digital imaging can determine the thickness of this breast tissue coverage, thus facilitating planning of the most adequate surgical techniques and reconstructive procedures for each case. Methods This study aimed to describe the results of a retrospective study of 352 digital mammograms in 176 patients with different breast volumes who underwent preoperative conservative mastectomies. The breast tissue coverage thickness and its relationship with the breast volume were evaluated. Results The breast tissue coverage thickness ranged from 0.233 to 4.423 cm, with a mean value of 1.952 cm. A comparison of tissue coverage and breast volume revealed a non-direct relationship between these factors. Conclusions Preoperative planning should not depend only on breast volume. Flap evaluations based on preoperative imaging measurements might be helpful when planning a conservative mastectomy. Accordingly, we propose a breast tissue coverage classification (BTCC). PMID:26855903

  14. Reducing radiation dose without compromising image quality in preoperative perforator flap imaging with CTA using ASIR technology.

    PubMed

    Niumsawatt, Vachara; Debrotwir, Andrew N; Rozen, Warren Matthew

    2014-01-01

    Computed tomographic angiography (CTA) has become a mainstay in preoperative perforator flap planning in the modern era of reconstructive surgery. However, the increased use of CTA does raise the concern of radiation exposure to patients. Several techniques have been developed to decrease radiation dosage without compromising image quality, with varying results. The most recent advance is in the improvement of image reconstruction using an adaptive statistical iterative reconstruction (ASIR) algorithm. We sought to evaluate the image quality of ASIR in preoperative deep inferior epigastric perforator (DIEP) flap surgery, through a direct comparison with conventional filtered back projection (FBP) images. A prospective review of 60 consecutive ASIR and 60 consecutive FBP CTA images using similar protocol (except for radiation dosage) was undertaken, analyzed by 2 independent reviewers. In both groups, we were able to accurately identify axial arteries and their perforators. Subjective analysis of image quality demonstrated no statistically significant difference between techniques. ASIR can thus be used for preoperative imaging with similar image quality to FBP, but with a 60% reduction in radiation delivery to patients. PMID:25058789

  15. Reducing Radiation Dose Without Compromising Image Quality in Preoperative Perforator Flap Imaging With CTA Using ASIR Technology

    PubMed Central

    Niumsawatt, Vachara; Debrotwir, Andrew N.; Rozen, Warren Matthew

    2014-01-01

    Computed tomographic angiography (CTA) has become a mainstay in preoperative perforator flap planning in the modern era of reconstructive surgery. However, the increased use of CTA does raise the concern of radiation exposure to patients. Several techniques have been developed to decrease radiation dosage without compromising image quality, with varying results. The most recent advance is in the improvement of image reconstruction using an adaptive statistical iterative reconstruction (ASIR) algorithm. We sought to evaluate the image quality of ASIR in preoperative deep inferior epigastric perforator (DIEP) flap surgery, through a direct comparison with conventional filtered back projection (FBP) images. A prospective review of 60 consecutive ASIR and 60 consecutive FBP CTA images using similar protocol (except for radiation dosage) was undertaken, analyzed by 2 independent reviewers. In both groups, we were able to accurately identify axial arteries and their perforators. Subjective analysis of image quality demonstrated no statistically significant difference between techniques. ASIR can thus be used for preoperative imaging with similar image quality to FBP, but with a 60% reduction in radiation delivery to patients. PMID:25058789

  16. Preoperative Oral Carbohydrate Loading in Pancreaticoduodenectomy

    PubMed Central

    Son, Kum-Hee; Kim, So-Young; Cho, Yeong-Ah; Han, Sung-Sik; Park, Sang-Jae

    2016-01-01

    Overnight fasting before elective surgery has been the routine to reduce the risk of pulmonary aspiration. Recently, several international guidelines for preoperative fasting recommend to intake carbohydrate-containing fluids up to 2 to 3 hours before the induction of anesthesia to improve postoperative recovery. Based on the recommendations, we developed a "preoperative carbohydrate diet" provided for the preoperative patients. The purpose of this case report is to share our experience of applying preoperative carbohydrate loading prior to surgery. PMID:27482525

  17. Background parenchymal enhancement in preoperative breast MRI

    PubMed Central

    Kohara, Satoko; Ishigaki, Satoko; Satake, Hiroko; Kawamura, Akiko; Kawai, Hisashi; Kikumori, Toyone; Naganawa, Shinji

    2015-01-01

    ABSTRACT We aimed to assess the influence of background parenchymal enhancement (BPE) on surgical planning performed using preoperative MRI for breast cancer evaluation. Between January 2009 and December 2010, 91 newly diagnosed breast cancer patients (mean age, 55.5 years; range, 30−88 years) who underwent preoperative bilateral breast MRI followed by planned breast conservation therapy were retrospectively enrolled. MRI was performed to assess the tumor extent in addition to mammography and breast ultrasonography. BPE in the contralateral normal breast MRI at the early dynamic phase was visually classified as follows: minimal (n=49), mild (n=27), moderate (n=7), and marked (n=8). The correlations between the BPE grade and age, menopausal status, index tumor size, changes in surgical management based on MRI results, positive predictive value (PPV) of MRI, and surgical margins were assessed. Patients in the strong BPE groups were significantly younger (p=0.002) and generally premenopausal (p<0.001). Surgical treatment was not changed in 67 cases (73.6%), while extended excision and mastectomy were performed in 12 cases (13.2%), each based on additional lesions on MRI. Six of 79 (7.6%) patients who underwent breast conservation therapy had tumor-positive resection margins. In cases where surgical management was changed, the PPV for MRI-detected foci was high in the minimal (91.7%) and mild groups (66.7%), and 0% in the moderate and marked groups (p=0.002). Strong BPE causes false-positive MRI findings and may lead to overly extensive surgery, whereas MRI may be beneficial in select patients with weak BPE. PMID:26412883

  18. FFTF preoperational survey. Program report

    SciTech Connect

    Twitty, B.L.; Bicehouse, H.J.

    1980-12-01

    The FFTF will become operational with criticality early in 1980. This facility is composed of the test reactor, fuel examination cells, expended fuel storage systems and fuel handling systems. The reactor and storage systems are sodium-cooled with the heat load dumped to the ambient air through heat exchangers. In order to assure that the operation of the FFTF has minimal impact on the environment, a monitoring program has been established. Prior to operation of a new facility, a preoperational environmental survey is required. It is the purpose of this report to briefly describe the environmental survey program and to provide the background data obtained during the preoperational phase of the survey program. Nine stations in the program of particular importance to FFTF are discussed in detail with results of monitoring given. No unexplained trends were noted.

  19. [Algorithm for treating preoperative anemia].

    PubMed

    Bisbe Vives, E; Basora Macaya, M

    2015-06-01

    Hemoglobin optimization and treatment of preoperative anemia in surgery with a moderate to high risk of surgical bleeding reduces the rate of transfusions and improves hemoglobin levels at discharge and can also improve postoperative outcomes. To this end, we need to schedule preoperative visits sufficiently in advance to treat the anemia. The treatment algorithm we propose comes with a simple checklist to determine whether we should refer the patient to a specialist or if we can treat the patient during the same visit. With the blood count test and additional tests for iron metabolism, inflammation parameter and glomerular filtration rate, we can decide whether to start the treatment with intravenous iron alone or erythropoietin with or without iron. With significant anemia, a visit after 15 days might be necessary to observe the response and supplement the treatment if required. The hemoglobin objective will depend on the type of surgery and the patient's characteristics. PMID:26320341

  20. MO-A-BRD-10: A Fast and Accurate GPU-Based Proton Transport Monte Carlo Simulation for Validating Proton Therapy Treatment Plans

    SciTech Connect

    Wan Chan Tseung, H; Ma, J; Beltran, C

    2014-06-15

    Purpose: To build a GPU-based Monte Carlo (MC) simulation of proton transport with detailed modeling of elastic and non-elastic (NE) protonnucleus interactions, for use in a very fast and cost-effective proton therapy treatment plan verification system. Methods: Using the CUDA framework, we implemented kernels for the following tasks: (1) Simulation of beam spots from our possible scanning nozzle configurations, (2) Proton propagation through CT geometry, taking into account nuclear elastic and multiple scattering, as well as energy straggling, (3) Bertini-style modeling of the intranuclear cascade stage of NE interactions, and (4) Simulation of nuclear evaporation. To validate our MC, we performed: (1) Secondary particle yield calculations in NE collisions with therapeutically-relevant nuclei, (2) Pencil-beam dose calculations in homogeneous phantoms, (3) A large number of treatment plan dose recalculations, and compared with Geant4.9.6p2/TOPAS. A workflow was devised for calculating plans from a commercially available treatment planning system, with scripts for reading DICOM files and generating inputs for our MC. Results: Yields, energy and angular distributions of secondaries from NE collisions on various nuclei are in good agreement with the Geant4.9.6p2 Bertini and Binary cascade models. The 3D-gamma pass rate at 2%–2mm for 70–230 MeV pencil-beam dose distributions in water, soft tissue, bone and Ti phantoms is 100%. The pass rate at 2%–2mm for treatment plan calculations is typically above 98%. The net computational time on a NVIDIA GTX680 card, including all CPU-GPU data transfers, is around 20s for 1×10{sup 7} proton histories. Conclusion: Our GPU-based proton transport MC is the first of its kind to include a detailed nuclear model to handle NE interactions on any nucleus. Dosimetric calculations demonstrate very good agreement with Geant4.9.6p2/TOPAS. Our MC is being integrated into a framework to perform fast routine clinical QA of pencil

  1. Combination of preoperative platelet/lymphocyte and neutrophil/lymphocyte rates and tumor-related factors to predict lymph node metastasis in patients with gastric cancer

    PubMed Central

    Pang, Wenyang; Lou, Neng; Jin, Cancan; Hu, Changyuan; Arvine, Chandoo; Shen, Xian

    2016-01-01

    Objective Lymph node (LN) metastasis is widely accepted as a poor prognosis indicator in patients with gastric cancer. An accurate preoperative prediction of LN status is of crucial importance for the planning treatment. The aim of the present study was to assess the predictive value of the preoperative platelet/lymphocyte (PLR) and neutrophil/lymphocyte rates (NLR) on the LN metastasis in gastric cancer patients and to develop a new preoperative score system to predict LN metastasis. Patients and methods A total of 492 operable patients with gastric cancer were enrolled in our study. The clinical utility of the PLR and NLR was evaluated by receiver operating characteristic (ROC) curves. The logistic analysis was used to identify the independent parameters associated with LN metastasis. Then, a score system including those independent parameters that can be detected preoperatively was established, which was also tested by an ROC curve. Results The ideal cutoff values for predicting LN metastasis were 1.59 for NLR and 155.67 for PLR according to the ROC curve. Multivariate analyses showed that both PLR and NLR are significantly associated with LN metastasis independent of depth of invasion, lymphatic invasion, macroscopic type, and tumor size. The area under the ROC curve of the score system was 0.830 (95% confidence interval 0.782–0.878), showing a reliable ability to evaluate the status of nodal involvement. Conclusion Preoperative PLR and NLR are useful biomarkers to predict LN metastasis and the score system in our study may serve as a reliable instrument to predict LN metastasis in gastric cancer patients. PMID:26854795

  2. Patterns of Response After Preoperative Treatment in Gastric Cancer

    SciTech Connect

    Diaz-Gonzalez, Juan A.; Rodriguez, Javier; Hernandez-Lizoain, Jose L.; Ciervide, Raquel; Gaztanaga, Miren; San Miguel, Inigo; Arbea, Leire; Aristu, J. Javier; Chopitea, Ana; Martinez-Regueira, Fernando; Valenti, Victor; Garcia-Foncillas, Jesus; Martinez-Monge, Rafael; Sola, Jesus J.

    2011-07-01

    Purpose: To analyze the rate of pathologic response in patients with locally advanced gastric cancer treated with preoperative chemotherapy with and without chemoradiation at our institution. Methods and Materials: From 2000 to 2007 patients were retrospectively identified who received preoperative treatment for gastric cancer (cT3-4/ N+) with induction chemotherapy (Ch) or with Ch followed by concurrent chemoradiotherapy (45 Gy in 5 weeks) (ChRT). Surgery was planned 4-6 weeks after the completion of neoadjuvant treatment. Pathologic assessment was used to investigate the patterns of pathologic response after neoadjuvant treatment. Results: Sixty-one patients were analyzed. Of 61 patients, 58 (95%) underwent surgery. The R0 resection rate was 87%. Pathologic complete response was achieved in 12% of the patients. A major pathologic response (<10% of residual tumor) was observed in 53% of patients, and T downstaging was observed in 75%. Median follow-up was 38.7 months. Median disease-free survival (DFS) was 36.5 months. The only patient-, tumor-, and treatment-related factor associated with pathologic response was the use of preoperative ChRT. Patients achieving major pathologic response had a 3-year actuarial DFS rate of 63%. Conclusions: The patterns of pathologic response after preoperative ChRT suggest encouraging intervals of DFS. Such a strategy may be of interest to be explored in gastric cancer.

  3. The relevance of preoperative ultrasound cervical mapping in patients with thyroid cancer

    PubMed Central

    Kocharyan, Davit; Schwenter, Frank; Bélair, Manon; Nassif, Edgard

    2016-01-01

    Background Cervical lymph node involvement in thyroid cancer is associated with locoregional recurrence and decreased disease-free survival. Preoperative lymph node mapping helps in planning surgery for neck dissection and improves patient outcomes. We sought to perform a qualitative and quantitative analysis of ultrasound mapping for thyroid cancer and evaluate the clinical importance of this exam in terms of identifying the group of patients who would benefit most from subsequent surgical dissection. Methods We retrospectively reviewed the cases of 263 patients who underwent thyroid surgery between 2009 and 2013. We calculated the positive predictive values (PPVs) of ultrasound mapping of both the lateral and central compartments together and the lateral or central compartment individually. A quantitative analysis was performed by comparing the number of positive lymph nodes at ultrasound imaging with histopathologic evaluation. Results A total of 136 cases of thyroid cancer in 120 patients met the inclusion criteria for ultrasound mapping analysis. The PPVs (and 95% confidence intervals) were 83.82 (0.76–0.89) for the lateral and central compartments, 85.39% (0.76–0.91) for the lateral compartment, and 80.48% (0.7–0.87) for the central compartment. When comparing the positive lymph nodes at ultrasound imaging with histopathologic evaluation, the result was χ2 = 10.33 (p = 0.006). Conclusion This single-institution study indicated that preoperative ultrasound mapping is an accurate imaging procedure for predicting lymphatic spread in differentiated and medullary thyroid cancer. Ultrasound mapping can be used as an efficient tool for surgical planning and prognosis determination, as well as for identifying the group of patients who would benefit most from subsequent surgical intervention. PMID:27007092

  4. Preoperative anemia and postoperative outcomes after hepatectomy

    PubMed Central

    Tohme, Samer; Varley, Patrick R.; Landsittel, Douglas P.; Chidi, Alexis P.; Tsung, Allan

    2015-01-01

    Background Preoperative anaemia is associated with adverse outcomes after surgery but outcomes after liver surgery specifically are not well established. We aimed to analyze the incidence of and effects of preoperative anemia on morbidity and mortality in patients undergoing liver resection. Methods All elective hepatectomies performed for the period 2005–2012 recorded in the American College of Surgeons' National Surgical Quality Improvement Program (ACS-NSQIP) database were evaluated. We obtained anonymized data for 30-day mortality and major morbidity (one or more major complication), demographics, and preoperative and perioperative risk factors. We used multivariable logistic regression models to assess the adjusted effect of anemia, which was defined as (hematocrit <39% in men, <36% in women), on postoperative outcomes. Results We obtained data for 12,987 patients, of whom 4260 (32.8%) had preoperative anemia. Patients with preoperative anemia experienced higher postoperative major morbidity and mortality rates compared to those without anemia. After adjustment for predefined variables, preoperative anemia was an independent risk factor for postoperative major morbidity (adjusted OR 1.21, 1.09–1.33). After adjustment, there was no significant difference in postoperative mortality for patients with or without preoperative anemia (adjusted OR 0.88, 0.66–1.16). Conclusion Preoperative anemia is independently associated with an increased risk of major morbidity in patients undergoing hepatectomy. Therefore, it is crucial to readdress preoperative blood management in anemic patients prior to hepatectomy. PMID:27017165

  5. The preoperative evaluation prevent the postoperative complications of thyroidectomy

    PubMed Central

    Huang, Chien-Feng; Jeng, Yachung; Chen, Kuo-Dong; Yu, Ji-Kuen; Shih, Chao-Ming; Huang, Shih-Ming; Lee, Chen-Hsen; Chou, Fong-Fu; Shih, Ming-Lang; Jeng, Kee-Ching; Chang, Tzu-Ming

    2014-01-01

    Objective Thyroid surgery is generally a safe surgery but its complications are still common. We wish to identify preoperative factors that predict postoperative complications. Methods A nationwide survey was conducted by senior surgeons from 16 medical centers and 5 regional hospitals in Taiwan to thyroid operations performed over 3 years. 3846 cases were retrospectively examined to identify factors influencing complications: indication for surgery, preoperative evaluation, such as ultrasonography, chest X-ray, computed tomography and magnetic resonance imaging, isotope scanning, fine-needle aspiration cytology (FNAC) and thyroid function test, and patient characteristics. Results Eighty-four percent of patients were female. Seven percent of the patients had immediate postoperative hypocalcemia (mild and severe) and 2.3%, hoarseness (recurrent laryngeal nerve (RLN) injury, temporary/permanent). Logistic regression analysis identified an association between hypocalcemia and RLN injury with age, hospital category, surgical procedure types (total thyroidectomy, unilateral, bilateral subtotal or total resection). A lower incidence of hypocalcemia was related to preoperative neck ultrasound and FNAC analysis (the odds ratio (OR) = 0.5 and 0.65, [95% confidence interval (CI) 0.331–0.768 and 0.459–0.911], P = 0.0014 and 0.0127, respectively), while RLN injury was not associated with any preoperative evaluation. The ORs of hypocalcemia and RLN injury for patients older than 50 years were 0.55 and 2.15, [0.393–0.763 and 1.356–3.4], P < 0.001 and 0.0012, respectively. Conclusions The success of thyroid surgery depends on careful preoperative planning, including a preoperative neck ultrasound to determine the proximity of the nodule to the recurrent laryngeal nerve course, and the consideration of the type of anesthesia, adjuvant devices for intra-op monitoring of the RLN, and surgical modalities. Our results suggest that preoperative evaluation implementations

  6. Treatment planning for resected abdominal tumors: Differences in organ position between diagnostic and radiation-planning computed tomography scans

    SciTech Connect

    Chen, Aileen B.; Mamon, Harvey . E-mail: hmamon@lroc.harvard.edu

    2005-12-01

    Purpose: To evaluate whether organ location, determined from preoperative diagnostic computed tomography scans (CTs), accurately reflects organ location when patients are positioned for radiation therapy. Methods and Materials: We identified patients with upper abdominal malignancies treated with surgery and/or radiation therapy. Comparisons of organ position relative to fixed bony landmarks were made among preoperative diagnostic CTs, postoperative diagnostic CTs, and radiation-planning CTs. We studied 18 patients who had CTs differing only in scanning technique, 11 patients who had CTs differing only in operative state, and 7 patients with CTs differing in both scanning technique and operative state. Results: For patients with diagnostic CTs and radiation-planning CTs that were either both preoperative or both postoperative, mean organ position, measured relative to a fixed bony landmark, ranged from 1.9 to 3.2 cm superior on radiation-planning CTs compared with diagnostic CTs (p < 0.0001). Mean organ position ranged from 0.9 to 1.7 cm posterior on radiation-planning CTs compared with diagnostic CTs (p {<=} 0.008). Shifts in the right-left direction were small and variable. For patients with pre- and postoperative diagnostic CTs, organ shifts were variable and not significant. Organ shifts for patients with preoperative diagnostic CTs and postoperative radiation-planning CTs were similar to shifts observed for the first group. Conclusions: Relative to bony landmarks, there are superior and posterior shifts in organ position for radiation-planning CTs compared with diagnostic CTs. These shifts should be considered during treatment planning for resected abdominal tumors.

  7. Magnification rate of digital panoramic radiographs and its effectiveness for pre-operative assessment of dental implants

    PubMed Central

    Kim, Y-K; Park, J-Y; Kim, S-G; Kim, J-S; Kim, J-D

    2011-01-01

    Objectives The purpose of this study was to determine the accuracy and effectiveness of digital panoramic radiographs for pre-operative assessment of dental implants. Methods We selected 86 patients (221 implants) and calculated the length of the planned implant based on the distance between a selection of critical anatomical structures and the alveolar crest using the scaling tools provided in the digital panoramic system. We analysed the magnification rate and the difference between the actual inserted implant length and planned implant length according to the location of the implant placement and the clarity of anatomical structures seen in the panoramic radiographs. Results There was no significant difference between the planned implant length and actual inserted implant length (P > 0.05). The magnification rate of the width and length of the inserted implants, seen in the digital panoramic radiographs, was 127.28 ± 13.47% and 128.22 ± 4.17%, respectively. The magnification rate of the implant width was largest in the mandibular anterior part and there was a significant difference in the magnification rate of the length of implants between the maxilla and the mandible (P < 0.05). When the clarity of anatomical structures seen in the panoramic radiographs is low, the magnification rate of the width of the inserted implants is significantly higher (P < 0.05), but there is no significant difference between the planned implant length and actual inserted implant length according to the clarity of anatomical structures (P < 0.05). Conclusions Digital panoramic radiography can be considered a simple, readily available and considerably accurate pre-operative assessment tool in the vertical dimension for dental implant therapy. PMID:21239569

  8. The Preoperative Patient With a Systolic Murmur

    PubMed Central

    Cowie, Brian

    2015-01-01

    Context: Patients with undifferentiated systolic murmurs present commonly during the perioperative period. Traditional bedside assessment and auscultation has not changed significantly in almost 200 years and relies on interpreting indirect acoustic events as a means of evaluating underlying cardiac pathology. This is notoriously inaccurate, even in expert cardiology hands, since many different valvular and cardiac diseases present with a similar auditory signal. Evidence Acquisition: The data on systolic murmurs, physical examination, perioperative valvular disease in the setting of non-cardiac surgery is reviewed. Results: Significant valvular heart disease increases perioperative risk in major non-cardiac surgery and increases long term patient morbidity and mortality. We propose a more modern approach to physical examination that incorporates the use of focused echocardiography to allow direct visualization of cardiac structure and function. This improves the diagnostic accuracy of clinical assessment, allows rational planning of surgery and anaesthesia technique, risk stratification, postoperative monitoring and appropriate referral to physicians and cardiologists. Conclusions: With a thorough preoperative assessment incorporating focused echocardiography, anaesthetists are in the unique position to enhance their role as perioperative physicians and influence short and long term outcomes of their patients. PMID:26705529

  9. Morphological analysis and preoperative simulation of a double-chambered right ventricle using 3-dimensional printing technology.

    PubMed

    Shirakawa, Takashi; Koyama, Yasushi; Mizoguchi, Hiroki; Yoshitatsu, Masao

    2016-05-01

    We present a case of a double-chambered right ventricle in adulthood, in which we tried a detailed morphological assessment and preoperative simulation using 3-dimensional (3D) heart models for improved surgical planning. Polygonal object data for the heart were constructed from computed tomography images of this patient, and transferred to a desktop 3D printer to print out models in actual size. Medical staff completed all of the work processes. Because the 3D heart models were examined by hand, observed from various viewpoints and measured by callipers with ease, we were able to create an image of the complete form of the heart. The anatomical structure of an anomalous bundle was clearly observed, and surgical approaches to the lesion were simulated accurately. During surgery, we used an incision on the pulmonary infundibulum and resected three muscular components of the stenosis. The similarity between the models and the actual heart was excellent. As a result, the operation for this rare defect was performed safely and successfully. We concluded that the custom-made model was useful for morphological analysis and preoperative simulation. PMID:26860990

  10. Utility of Discography as a Preoperative Diagnostic Tool for Intradural Lumbar Disc Herniation

    PubMed Central

    Toyoda, Hiromitsu; Terai, Hidetomi; Dohzono, Sho; Hori, Yusuke; Nakamura, Hiroaki

    2016-01-01

    Preoperative definitive diagnosis of intradural lumbar disc herniation (ILDH) is difficult despite the availability of various neuroradiological investigative tools. We present a case of ILDH diagnosed preoperatively by discography and computed tomography-discography (disco-CT).The patient was a 63-year-old man with acute excruciating right leg pain. Discography and disco-CT demonstrated leakage of the contrast medium into the intradural space. Based on these findings, a right L5 nerve root disturbance caused by ILDH was diagnosed. A right L5 hemi-laminectomy and a dorsal durotomy were performed. The herniated disc was carefully dissected and then completely removed. Three months after surgery, the patient had fully recovered. This report highlights the importance of making a definitive diagnosis of ILDH preoperatively for better surgical planning and improved clinical outcomes. Furthermore, discography and disco-CT are both useful preoperative diagnostic tools for the diagnosis of ILDH. PMID:27559461

  11. Utility of Discography as a Preoperative Diagnostic Tool for Intradural Lumbar Disc Herniation.

    PubMed

    Matsumoto, Tomiya; Toyoda, Hiromitsu; Terai, Hidetomi; Dohzono, Sho; Hori, Yusuke; Nakamura, Hiroaki

    2016-08-01

    Preoperative definitive diagnosis of intradural lumbar disc herniation (ILDH) is difficult despite the availability of various neuroradiological investigative tools. We present a case of ILDH diagnosed preoperatively by discography and computed tomography-discography (disco-CT).The patient was a 63-year-old man with acute excruciating right leg pain. Discography and disco-CT demonstrated leakage of the contrast medium into the intradural space. Based on these findings, a right L5 nerve root disturbance caused by ILDH was diagnosed. A right L5 hemi-laminectomy and a dorsal durotomy were performed. The herniated disc was carefully dissected and then completely removed. Three months after surgery, the patient had fully recovered. This report highlights the importance of making a definitive diagnosis of ILDH preoperatively for better surgical planning and improved clinical outcomes. Furthermore, discography and disco-CT are both useful preoperative diagnostic tools for the diagnosis of ILDH. PMID:27559461

  12. Preoperative radiotherapy for colorectal cancer.

    PubMed Central

    Higgins, G A; Conn, J H; Jordan, P H; Humphrey, E W; Roswit, B; Keehn, R J

    1975-01-01

    In a prospective randomized trial, 700 patients with a confirmed histological diagnosis of adenocarcinoma of the rectum or rectosigmoid were randomized to receive radiotherapy prior to operation (2000 to 2500 rads in two weeks) or surgery alone. Five year observed survival in the 453 patients on whom "curative" resection was possible was 48.5% in the X-ray treated group compared with 38.8% in controls, while in the 305 having low lying lesions requiring abdominoperineal resection, survival in the treated group was 46.9% compared with 34.3% in controls. Although suggestive of a treatment benefit, neither is considered statistically significant. Histologically positive lymph nodes were found in 41.2% of the control group and in only 27.8% of the patients receiving radiotherapy. Reveiw of all patients who died during the study shows a consistently lower death rate from cancer in the radiotherapy group. Although this study suggests a treatment benefit from preoperative radiotherapy, further studies now in progress by this group and others are necessary to determine the optimal dose regimen. PMID:805571

  13. Preoperative skin disinfection methodologies for reducing prosthetic joint infections.

    PubMed

    Banerjee, Samik; Kapadia, Bhaveen H; Mont, Michael A

    2014-08-01

    Surgical site infections following lower extremity total joint arthroplasty procedures remain a substantial economic burden to the patient, the treating institution, and the health care system. The complexity of these surgical procedures creates the potential for various patient- or surgery-related risk factors for infection. Although there is much literature regarding the use of many preventative methods, a consensus regarding the true efficacy and application of such practices is generally not available. In this review, we reviewed the preoperative skin disinfection methodologies that have been used for reducing periprosthetic infections following lower extremity total joint arthroplasty. Currently, cumulative evidence suggests that preoperative chlorhexidine baths or chlorhexidine-impregnated wipes may reduce the colonization of pathogenic organisms on the skin. In addition, multiple showers or topical applications of chlorhexidine may lead to more substantial reduction in colony counts. Advanced preoperative whole-body cleaning with chlorhexidine-containing cloths rather than site-specific application may confer additional advantages. Further randomized controlled trials with carefully planned protocols and endpoints are needed to determine if this conclusively leads to reduction in the rate of surgical site infections. PMID:24622912

  14. Evolution of Preoperative Rhinoplasty Consult by Computer Imaging.

    PubMed

    Lekakis, Garyfalia; Claes, Peter; Hamilton, Grant S; Hellings, P W

    2016-02-01

    The preoperative consultation in rhinoplasty involves a multitude of actions that are mandatory for the decision-making process: history taking with attention to the symptoms and specific requests of the patient, clinical evaluation of the aesthetics, the functional status of the nose and the patients' motivation for surgery, and acquisition of standardized preoperative photographs. During the last decade, computer imaging or morphing of the preoperative pictures of the nose has become much more common. This part of the consultation allows the surgeon and patient to reach a mutually agreeable set of expectations by demonstrating the planned outcome of rhinoplasty and describing the objectives of surgery. The evolving literature on computer imaging supports that the benefits for both the patients and surgeons seem to outweigh the risks. Indeed, morphing enables the surgeon to precisely explain to the patients the goal of surgery, and to postpone or even cancel surgery in the group of patients that do not appear satisfied with the proposed changes. In addition, patients may feel more prepared for surgery and have a more realistic view of the outcome of the intervention. Presently, computer imaging is progressing from 2D to 3D models, optimizing the surgeons' capacity to perform morphing in the most advantageous manner for both parties. The current review provides a state-of-the art analysis on morphing in rhinoplasty, putting morphing into a historic and relevant perspective in clinical practice. PMID:26862968

  15. Effects of comfort warming on preoperative patients.

    PubMed

    Wagner, Doreen; Byrne, Michelle; Kolcaba, Katharine

    2006-09-01

    THERMAL COMFORT IS ONE DIMENSION of overall patient comfort, and it usually is addressed by covering the patient with warmed cotton blankets. WARMING HELPS A PATIENT maintain normothermia and appears to decrease patient anxiety. AN STUDY WAS CONDUCTED in a preoperative setting to compare the effects of preoperative warming with warmed cotton blankets versus patient-controlled warming gowns on patients' perceptions of thermal comfort and anxiety. BOTH WARMING INTERVENTIONS had a positive effect on patients' thermal comfort and sense of well-being. Patients who used the patient-controlled warming gown also experienced a significant reduction in preoperative anxiety. PMID:17004666

  16. [Preoperative assessment for extended hepatic resection].

    PubMed

    Martin, David; Roulin, Didier; Takamune, Yamaguchi; Demartines, Nicolas; Halkic, Nermin

    2016-06-15

    The number of major hepatectomy performed for the treatment of primary or secondary liver cancer has increased over the past two decades. By definition, a major hepatectomy includes the resection of at least three liversegments. Advances in anesthesiology, surgical and radiological techniques and perioperative management allowed a broad patient selection with increased security. Every case must be discussed in multidisciplinary tumor board, and preoperative assessment should include biological, volumetric and functional hepatic parameters. In case of preoperative insufficient liver volume, portal vein embolization allows increasing the size of liver remnant. This paper aims describing preoperative work-up. PMID:27487623

  17. Preoperative Evaluation of the Surgical Patient.

    PubMed

    O'Donnell, Frederick T

    2016-01-01

    Primary care physicians and specialists are frequently involved in the care of surgical patients. Changes in reimbursement have prompted re-examination of preoperative testing and health care expenditures. Physicians have additional incentives to improve health care delivery and reduce costs. The perioperative surgical home concept involves coordinating all aspects of patient care, including behavioral modifications, during the perioperative period. Evidence-based guidelines on preoperative evaluation are available to assist practitioners in managing cardiovascular disease, and communicating surgical risks. Shared decision making in the preoperative period can improve surgical outcomes and patient satisfaction. PMID:27443045

  18. The value of preoperative functional cortical mapping using navigated TMS.

    PubMed

    Lefaucheur, Jean-Pascal; Picht, Thomas

    2016-04-01

    The surgical removal of brain tumours in so-called eloquent regions is frequently associated with a high risk of causing disabling postoperative deficits. Among the preoperative techniques proposed to help neurosurgical planning and procedure, navigated transcranial magnetic stimulation (nTMS) is increasingly performed. A high level of evidence is now available in the literature regarding the anatomical and functional accuracy of this mapping technique. This article presents the principles and facts demonstrating the value of using nTMS in clinical practice to preserve motor or language functions from deleterious lesions secondary to brain tumour resection or epilepsy surgery. PMID:27229765

  19. Preoperative evaluation of the cardiac patient for noncardiac surgery.

    PubMed Central

    Fleisher, L. A.; Barash, P. G.

    1993-01-01

    Perioperative cardiac events continue to represent a significant cause of morbidity in patients undergoing noncardiac surgery. The evaluation of the high risk patient should begin with an assessment of the probability of coronary artery disease and exercise tolerance. Decisions to undergo further evaluation, including noninvasive testing, should be based upon the perioperative morbidity and mortality rate for the planned surgical procedure. In patients with significant coronary artery stenoses and a high probability of perioperative cardiac morbidity, coronary artery bypass grafting, percutaneous transluminal coronary angioplasty, and preoperative optimization of hemodynamics in an intensive care unit have all been advocated as means of reducing risk. PMID:7825340

  20. Preoperative telemedicine evaluation of surgical mission patients: should we use it routinely?

    PubMed

    Latifi, Rifat; Mora, Francisco; Bekteshi, Flamur; Rivera, Renato

    2014-01-01

    Low-cost telemedicine is a viable and secure tool for preoperative evaluation of surgical mission patients. It increases efficiency and optimizes the use of existing resources. More specifically, it helps ensure an accurate assessment of patients before the surgical team arrives, reduces on-site prescreening time, and decreases the number of surgical candidates on the waiting list. Routine use of telemedicine in surgical missions most likely would reduce preoperative times and the number of operations canceled at the last minute. Moreover, it may be effectively used for long-term follow-up care, including the management of any postoperative complications. PMID:24552027

  1. A novel computational method for real-time preoperative assessment of primary dental implant stability.

    PubMed

    Olsen, Sigbjørn; Ferguson, Stephen J; Sigrist, Christian; Fritz, Wolf-Rüdiger; Nolte, Lutz P; Hallermann, Wock; Caversaccio, Marco

    2005-02-01

    A novel methodology which allows for fast and fully automatic structural analysis during preoperative planning for dental implant surgery is presented. This method integrates a fully automatic fast finite element solver within the framework of new concepts in computer-assisted preoperative planning for implant surgery. The planning system including optimized structural planning was validated by experimental results. Nine implants were placed in pig mandibles and mechanically loaded using a testing rig. The resulting displacements were measured and compared with those predicted by numerical analysis during planning. The results show that there were no statistically significant differences (P = 0.65) between the results of the models and the experiments. The results show that fast structural analysis can be integrated with surgical planning software allowing the initial axial implant stability to be predicted in real time during planning. It is believed that such a system could be used to select patients for immediate implant loading and, when further developed, be useful in other areas of preoperative surgical planning. PMID:15642031

  2. Preoperative Antibiotics and Mortality in the Elderly

    PubMed Central

    Silber, Jeffrey H.; Rosenbaum, Paul R.; Trudeau, Martha E.; Chen, Wei; Zhang, Xuemei; Lorch, Scott A.; Kelz, Rachel Rapaport; Mosher, Rachel E.; Even-Shoshan, Orit

    2005-01-01

    Objective and Background: It is generally thought that the use of preoperative antibiotics reduces the risk of postoperative infection, yet few studies have described the association between preoperative antibiotics and the risk of dying. The objective of this study was to determine whether preoperative antibiotics are associated with a reduced risk of death. Methods: We performed a multivariate matched, population-based, case-control study of death following surgery on 1362 Pennsylvania Medicare patients between 65 and 85 years of age undergoing general and orthopedic surgery. Cases (681 deaths within 60 days from hospital admission) were randomly selected throughout Pennsylvania using claims from 1995 and 1996. Models were developed to scan Medicare claims, looking for controls who did not die and who were the closest matches to the previously selected cases based on preoperative characteristics. Cases and their controls were identified, and charts were abstracted to define antibiotic use and obtain baseline severity adjustment data. Results: For general surgery, the odds of dying within 60 days were less than half in those treated with preoperative antibiotics within 2 hours of incision as compared with those without such treatment: (odds ratio = 0.44; 95% confidence interval, 0.32–0.60), P < 0.0001). For orthopedic surgery, no significant mortality reduction was observed (OR = 0.85; 95% confidence interval, 0.54–1.32; P < 0.464). Interpretation: Preoperative antibiotics are associated with a substantially lower 60-day mortality rate in elderly patients undergoing general surgery. In patients who appear to be comparable, the risk of death was half as large among those who received preoperative antibiotics. PMID:15973108

  3. Estimation of operative line of resection using preoperative image and nonrigid registration.

    PubMed

    Lee, Jong-Ha; Won, Chang-Hee; Kong, Seong-Gon

    2008-01-01

    Even though accurate diagnosis of organs is done using preoperative images such as CT or MRI, these information are not directly used in the operating room, because organs are nonrigid and their shapes change with time. In this paper, we propose to obtain an intraoperative image of an open organ and fuse the image with a preoperative image. The intraoperative image is obtained from a three-dimensional laser scanner. The registration of preoperative image to the intraoperative image can relate the information from the preoperative image to the open organ in the operating room. We do this by registering preoperative images to intraoperative images. An algorithm based on Robust Point Matching method is developed for this nonrigid image registration problem. We also propose a new metric called Non Overlapping Ratio to determine the registration error. The experiments demonstrate that the proposed method is capable of achieving region of interest estimation within 1.51 mm mean distance error and 0.66% Non Overlapping Ratio. PMID:19163585

  4. Preoperative defining system for pancreatic head cancer considering surgical resection

    PubMed Central

    Yang, Seok Jeong; Hwang, Ho Kyoung; Kang, Chang Moo; Lee, Woo Jung

    2016-01-01

    AIM: To provide appropriate treatment, it is crucial to share the clinical status of pancreas head cancer among multidisciplinary treatment members. METHODS: A retrospective analysis of the medical records of 113 patients who underwent surgery for pancreas head cancer from January 2008 to December 2012 was performed. We developed preoperative defining system of pancreatic head cancer by describing “resectability - tumor location - vascular relationship - adjacent organ involvement - preoperative CA19-9 (initial bilirubin level) - vascular anomaly”. The oncologic correlations with this reporting system were evaluated. RESULTS: Among 113 patients, there were 75 patients (66.4%) with resectable, 34 patients (30.1%) with borderline resectable, and 4 patients (3.5%) with locally advanced pancreatic cancer. Mean disease-free survival was 24.8 mo (95%CI: 19.6-30.1) with a 5-year disease-free survival rate of 13.5%. Pretreatment tumor size ≥ 2.4 cm [Exp(B) = 3.608, 95%CI: 1.512-8.609, P = 0.044] and radiologic vascular invasion [Exp(B) = 5.553, 95%CI: 2.269-14.589, P = 0.002] were independent predictive factors for neoadjuvant treatment. Borderline resectability [Exp(B) = 0.222, P = 0.008], pancreatic head cancer involving the pancreatic neck [Exp(B) = 9.461, P = 0.001] and arterial invasion [Exp(B) = 6.208, P = 0.010], and adjusted CA19-9 ≥ 50 [Exp(B) = 1.972 P = 0.019] were identified as prognostic clinical factors to predict tumor recurrence. CONCLUSION: The suggested preoperative defining system can help with designing treatment plans and also predict oncologic outcomes. PMID:27468199

  5. Importance of dynamic aortic evaluation in planning TEVAR

    PubMed Central

    van Herwaarden, Joost A.; Conti, Michele; Auricchio, Ferdinando; Rampoldi, Vincenzo; Trimarchi, Santi; Moll, Frans L.

    2014-01-01

    Dynamic aortic evaluation in planning thoracic endovascular aortic repair (TEVAR) is important to provide optimal stent graft sizing. Static imaging protocols do not consider normal aortic dynamics and may lead to stent graft to aorta mismatch, causing stent graft related complications, such as type I endoleak and stent graft migration. Dynamic imaging can assist in accurate stent graft selection and sizing preoperatively, and evaluate stent graft performance during follow-up. To create new imaging technologies, integration of knowledge between diverse scientific fields is essential (i.e., engineering, informatics and medicine). Different dynamic imaging modalities, such as electrocardiographic-gated computed tomography angiography (ECG-gated CTA) and four-dimensional phase-contrast MRI (4D PC-MRI), are progressively investigated and implemented into clinical practice as important instruments in preoperative planning for TEVAR. In time, further application of dynamic imaging tools for preoperative screening and follow-up after TEVAR might lead to better outcomes for patients. The advances in dynamic imaging for evaluation of the thoracic aorta using new imaging modalities and their future perspectives are addressed in this manuscript. PMID:24967170

  6. Preoperational test report, vent building ventilation system

    SciTech Connect

    Clifton, F.T.

    1997-11-04

    This represents a preoperational test report for Vent Building Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides Heating, Ventilation, and Air Conditioning (HVAC) for the W-030 Ventilation Building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  7. Preoperational test report, primary ventilation system

    SciTech Connect

    Clifton, F.T.

    1997-11-04

    This represents a preoperational test report for Primary Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space filtered venting of tanks AY101, AY102, AZ101, AZ102. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  8. Preoperative mechanical preparation of the colon: the patient's experience

    PubMed Central

    Jung, Barbel; Lannerstad, Olof; Påhlman, Lars; Arodell, Malin; Unosson, Mitra; Nilsson, Erik

    2007-01-01

    Background Preoperative mechanical bowel preparation can be questioned as standard procedure in colon surgery, based on the result from several randomised trials. Methods As part of a large multicenter trial, 105 patients planned for elective colon surgery for cancer, adenoma, or diverticulitis in three hospitals were asked to complete a questionnaire regarding perceived health including experience with bowel preparation. There were 39 questions, each having 3 – 10 answer alternatives, dealing with food intake, pain, discomfort, nausea/vomiting, gas distension, anxiety, tiredness, need of assistance with bowel preparation, and willingness to undergo the procedure again if necessary. Results 60 patients received mechanical bowel preparation (MBP) and 45 patients did not (No-MBP). In the MBP group 52% needed assistance with bowel preparation and 30% would consider undergoing the same preoperative procedure again. In the No-MBP group 65 % of the patients were positive to no bowel preparation. There was no significant difference between the two groups with respect to postoperative pain and nausea. On Day 4 (but not on Days 1 and 7 postoperatively) patients in the No-MBP group perceived more discomfort than patients in the MBP group, p = 0.02. Time to intake of fluid and solid food did not differ between the two groups. Bowel emptying occurred significantly earlier in the No-MBP group than in the MBP group, p = 0.03. Conclusion Mechanical bowel preparation is distressing for the patient and associated with a prolonged time to first bowel emptying. PMID:17480223

  9. Grading More Accurately

    ERIC Educational Resources Information Center

    Rom, Mark Carl

    2011-01-01

    Grades matter. College grading systems, however, are often ad hoc and prone to mistakes. This essay focuses on one factor that contributes to high-quality grading systems: grading accuracy (or "efficiency"). I proceed in several steps. First, I discuss the elements of "efficient" (i.e., accurate) grading. Next, I present analytical results…

  10. Preoperative and surveillance MR imaging of patients undergoing cytoreductive surgery and heated intraperitoneal chemotherapy

    PubMed Central

    2016-01-01

    MR imaging provides considerable advantages for imaging patients with peritoneal tumor. Its inherently superior contrast resolution compared to CT allows MRI to more accurately depict small peritoneal tumors that are often missed on other imaging tests. Combining different contrast mechanisms including diffusion-weighted (DW) MRI and gadolinium-enhanced MRI provides a powerful tool for preoperative and surveillance imaging in patients being considered for cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC). PMID:26941984

  11. Accurate monotone cubic interpolation

    NASA Technical Reports Server (NTRS)

    Huynh, Hung T.

    1991-01-01

    Monotone piecewise cubic interpolants are simple and effective. They are generally third-order accurate, except near strict local extrema where accuracy degenerates to second-order due to the monotonicity constraint. Algorithms for piecewise cubic interpolants, which preserve monotonicity as well as uniform third and fourth-order accuracy are presented. The gain of accuracy is obtained by relaxing the monotonicity constraint in a geometric framework in which the median function plays a crucial role.

  12. Accurate Finite Difference Algorithms

    NASA Technical Reports Server (NTRS)

    Goodrich, John W.

    1996-01-01

    Two families of finite difference algorithms for computational aeroacoustics are presented and compared. All of the algorithms are single step explicit methods, they have the same order of accuracy in both space and time, with examples up to eleventh order, and they have multidimensional extensions. One of the algorithm families has spectral like high resolution. Propagation with high order and high resolution algorithms can produce accurate results after O(10(exp 6)) periods of propagation with eight grid points per wavelength.

  13. Strategy for accurate liver intervention by an optical tracking system

    PubMed Central

    Lin, Qinyong; Yang, Rongqian; Cai, Ken; Guan, Peifeng; Xiao, Weihu; Wu, Xiaoming

    2015-01-01

    Image-guided navigation for radiofrequency ablation of liver tumors requires the accurate guidance of needle insertion into a tumor target. The main challenge of image-guided navigation for radiofrequency ablation of liver tumors is the occurrence of liver deformations caused by respiratory motion. This study reports a strategy of real-time automatic registration to track custom fiducial markers glued onto the surface of a patient’s abdomen to find the respiratory phase, in which the static preoperative CT is performed. Custom fiducial markers are designed. Real-time automatic registration method consists of the automatic localization of custom fiducial markers in the patient and image spaces. The fiducial registration error is calculated in real time and indicates if the current respiratory phase corresponds to the phase of the static preoperative CT. To demonstrate the feasibility of the proposed strategy, a liver simulator is constructed and two volunteers are involved in the preliminary experiments. An ex-vivo porcine liver model is employed to further verify the strategy for liver intervention. Experimental results demonstrate that real-time automatic registration method is rapid, accurate, and feasible for capturing the respiratory phase from which the static preoperative CT anatomical model is generated by tracking the movement of the skin-adhered custom fiducial markers. PMID:26417501

  14. Preoperative Evaluation: Estimation of Pulmonary Risk.

    PubMed

    Lakshminarasimhachar, Anand; Smetana, Gerald W

    2016-03-01

    Postoperative pulmonary complications (PPCs) are common after major non-thoracic surgery and associated with significant morbidity and high cost of care. A number of risk factors are strong predictors of PPCs. The overall goal of the preoperative pulmonary evaluation is to identify these potential, patient and procedure-related risks and optimize the health of the patients before surgery. A thorough clinical examination supported by appropriate laboratory tests will help guide the clinician to provide optimal perioperative care. PMID:26927740

  15. Implications of preoperative hypoalbuminemia in colorectal surgery.

    PubMed

    Truong, Adam; Hanna, Mark H; Moghadamyeghaneh, Zhobin; Stamos, Michael J

    2016-05-27

    Serum albumin has traditionally been used as a quantitative measure of a patient's nutritional status because of its availability and low cost. While malnutrition has a clear definition within both the American and European Societies for Parenteral and Enteral Nutrition clinical guidelines, individual surgeons often determine nutritional status anecdotally. Preoperative albumin level has been shown to be the best predictor of mortality after colorectal cancer surgery. Specifically in colorectal surgical patients, hypoalbuminemia significantly increases the length of hospital stay, rates of surgical site infections, enterocutaneous fistula risk, and deep vein thrombosis formation. The delay of surgical procedures to allow for preoperative correction of albumin levels in hypoalbuminemic patients has been shown to improve the morbidity and mortality in patients with severe nutritional risk. The importance of preoperative albumin levels and the patient's chronic inflammatory state on the postoperative morbidity and mortality has led to the development of a variety of surgical scoring systems to predict outcomes efficiently. This review attempts to provide a systematic overview of albumin and its role and implications in colorectal surgery. PMID:27231513

  16. Implications of preoperative hypoalbuminemia in colorectal surgery

    PubMed Central

    Truong, Adam; Hanna, Mark H; Moghadamyeghaneh, Zhobin; Stamos, Michael J

    2016-01-01

    Serum albumin has traditionally been used as a quantitative measure of a patient’s nutritional status because of its availability and low cost. While malnutrition has a clear definition within both the American and European Societies for Parenteral and Enteral Nutrition clinical guidelines, individual surgeons often determine nutritional status anecdotally. Preoperative albumin level has been shown to be the best predictor of mortality after colorectal cancer surgery. Specifically in colorectal surgical patients, hypoalbuminemia significantly increases the length of hospital stay, rates of surgical site infections, enterocutaneous fistula risk, and deep vein thrombosis formation. The delay of surgical procedures to allow for preoperative correction of albumin levels in hypoalbuminemic patients has been shown to improve the morbidity and mortality in patients with severe nutritional risk. The importance of preoperative albumin levels and the patient’s chronic inflammatory state on the postoperative morbidity and mortality has led to the development of a variety of surgical scoring systems to predict outcomes efficiently. This review attempts to provide a systematic overview of albumin and its role and implications in colorectal surgery. PMID:27231513

  17. Pre-operative drilling simulation method for dental implant treatment.

    PubMed

    Arataki, Tomohiko; Furuya, Yoshitaka; Ito, Taichi; Miyashita, Yuko; Shimamura, Ichiro; Yajima, Yasutomo

    2007-02-01

    The position, depth and direction of implant placement are often planned based on evaluation of radiographs and study casts. Insertion planned in such a manner may not be adequate for precise and safe surgery in some cases due to inadequate working clearance in the oral cavity. In order to obtain high initial stability and ensure osseointegration at the implant-bone interface, careful and precise drilling must be performed at the implant placement site. Therefore, we propose the necessity of evaluating the operability of implant treatment-devices prior to surgery. The amount of handling space needed during implant placement surgery was determined. The results showed that for implants with a length of 7-18 mm, a vertical distance of as much as 50-60 mm was required, depending on the implant platform. These results suggest the necessity of pre-operative drilling simulation in each individual. Handling space was measured with angled heads and probes fabricated on a trial basis for pre-surgical drilling simulation in the oral cavity. We believe that these instruments may be clinically useful in estimating the amount of handling space required prior to surgery and ensuring precise implant placement. Evaluation of the intra-oral environment for handling of treatment devices should be included in the pre-surgical intra-oral evaluation of dental implant cases to avoid changes in treatment planning due to intra-oral interference during the course of surgery. PMID:17721064

  18. The role of endoscopic ultrasound on the preoperative T staging of gastric cancer: A retrospective study.

    PubMed

    Han, Chaoqun; Lin, Rong; Shi, Huiying; Liu, Jun; Qian, Wei; Ding, Zhen; Hou, Xiaohua

    2016-09-01

    Endoscopic ultrasonography (EUS) is used for preoperative assessment of gastric cancer. However, recent studies suggested that EUS staging accuracy is lower than previously thought. We aimed to assess EUS efficacy and image characteristics in preoperative gastric cancer T staging.A retrospective review of clinical and imaging features of 232 gastric carcinoma patients who underwent preoperative EUS assessment of T stage was performed. Only cases with tumor-free resection margin status and no metastases were enrolled. Comparisons of preoperative EUS and postoperative histopathological stagings were also performed to identify vital EUS image features for evaluating gastric carcinoma.EUS accuracy for T staging was 64.2% (149/232) with the highest accuracy for T3 (75.0%). Enlarged lymph nodes, well differentiated histological type and Borrmann IV type were associated with diagnostic accuracy in predicting tumor invasion. Although no factors were associated with overstaging, circumferential lesions ≥1/2, signet ring cell adenocarcinoma, and Borrmann IV type had significantly higher risks of understaging. Gastric wall outer edge irregularity was also an indicator of serosal involvement with a sensitivity of 82.0%. The pancreas and colon were more frequent disease extension sites than previously predicted.Although EUS is likely the best and most accurate option that we have used to stage gastric cancer, the finding that factors including circumferential lesions, signet ring cell adenocarcinoma, and Borrmann IV type carcinoma were more frequently related to incorrect staging warrants attention. PMID:27603347

  19. Preliminary Development of a Workstation for Craniomaxillofacial Surgical Procedures: Introducing a Computer-Assisted Planning and Execution System

    PubMed Central

    Gordon, Chad R.; Murphy, Ryan J.; Coon, Devin; Basafa, Ehsan; Otake, Yoshito; Al Rakan, Mohammed; Rada, Erin; Susarla, Sriniras; Swanson, Edward; Fishman, Elliot; Santiago, Gabriel; Brandacher, Gerald; Liacouras, Peter; Grant, Gerald; Armand, Mehran

    2014-01-01

    Introduction Facial transplantation represents one of the most complicated scenarios in craniofacial surgery because of skeletal, aesthetic, and dental discrepancies between donor and recipient. However, standard off-the-shelf vendor computer-assisted surgery systems may not provide custom features to mitigate the increased complexity of this particular procedure. We propose to develop a computer-assisted surgery solution customized for preoperative planning, intraoperative navigation including cutting guides, and dynamic, instantaneous feedback of cephalometric measurements/angles as needed for facial transplantation. Methods We developed the Computer-Assisted Planning and Execution (CAPE) workstation to assist with planning and execution of facial transplantation. Preoperative maxillofacial computed tomography (CT) scans were obtained on 4 size-mismatched miniature swine encompassing 2 live face-jaw-teeth transplants. The system was tested in a laboratory setting using plastic models of mismatched swine, after which the system was used in 2 live swine transplants. Postoperative CT imaging was obtained and compared with the preoperative plan and intraoperative measures from the CAPE workstation for both transplants. Results Plastic model tests familiarized the team with the CAPE workstation and identified several defects in the workflow. Live swine surgeries demonstrated utility of the CAPE system in the operating room, showing submillimeter registration error of 0.6 ± 0.24 mm and promising qualitative comparisons between intraoperative data and postoperative CT imaging. Conclusions The initial development of the CAPE workstation demonstrated integration of computer planning and intraoperative navigation for facial transplantation are possible with submillimeter accuracy. This approach can potentially improve preoperative planning, allowing ideal donor-recipient matching despite significant size mismatch, and accurate surgical execution. PMID:24406592

  20. Accurate measurement of time

    NASA Astrophysics Data System (ADS)

    Itano, Wayne M.; Ramsey, Norman F.

    1993-07-01

    The paper discusses current methods for accurate measurements of time by conventional atomic clocks, with particular attention given to the principles of operation of atomic-beam frequency standards, atomic hydrogen masers, and atomic fountain and to the potential use of strings of trapped mercury ions as a time device more stable than conventional atomic clocks. The areas of application of the ultraprecise and ultrastable time-measuring devices that tax the capacity of modern atomic clocks include radio astronomy and tests of relativity. The paper also discusses practical applications of ultraprecise clocks, such as navigation of space vehicles and pinpointing the exact position of ships and other objects on earth using the GPS.

  1. Accurate quantum chemical calculations

    NASA Technical Reports Server (NTRS)

    Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Taylor, Peter R.

    1989-01-01

    An important goal of quantum chemical calculations is to provide an understanding of chemical bonding and molecular electronic structure. A second goal, the prediction of energy differences to chemical accuracy, has been much harder to attain. First, the computational resources required to achieve such accuracy are very large, and second, it is not straightforward to demonstrate that an apparently accurate result, in terms of agreement with experiment, does not result from a cancellation of errors. Recent advances in electronic structure methodology, coupled with the power of vector supercomputers, have made it possible to solve a number of electronic structure problems exactly using the full configuration interaction (FCI) method within a subspace of the complete Hilbert space. These exact results can be used to benchmark approximate techniques that are applicable to a wider range of chemical and physical problems. The methodology of many-electron quantum chemistry is reviewed. Methods are considered in detail for performing FCI calculations. The application of FCI methods to several three-electron problems in molecular physics are discussed. A number of benchmark applications of FCI wave functions are described. Atomic basis sets and the development of improved methods for handling very large basis sets are discussed: these are then applied to a number of chemical and spectroscopic problems; to transition metals; and to problems involving potential energy surfaces. Although the experiences described give considerable grounds for optimism about the general ability to perform accurate calculations, there are several problems that have proved less tractable, at least with current computer resources, and these and possible solutions are discussed.

  2. Association of Preoperative Biliary Drainage With Postoperative Outcome Following Pancreaticoduodenectomy

    PubMed Central

    Povoski, Stephen P.; Karpeh, Martin S.; Conlon, Kevin C.; Blumgart, Leslie H.; Brennan, Murray F.

    1999-01-01

    Objective To determine whether preoperative biliary instrumentation and preoperative biliary drainage are associated with increased morbidity and mortality rates after pancreaticoduodenectomy. Summary Background Data Pancreaticoduodenectomy is accompanied by a considerable rate of postoperative complications and potential death. Controversy exists regarding the impact of preoperative biliary instrumentation and preoperative biliary drainage on morbidity and mortality rates after pancreaticoduodenectomy. Methods Two hundred forty consecutive cases of pancreaticoduodenectomy performed between January 1994 and January 1997 were analyzed. Multiple preoperative, intraoperative, and postoperative variables were examined. Pearson chi square analysis or Fisher’s exact test, when appropriate, was used for univariate comparison of all variables. Logistic regression was used for multivariate analysis. Results One hundred seventy-five patients (73%) underwent preoperative biliary instrumentation (endoscopic, percutaneous, or surgical instrumentation). One hundred twenty-six patients (53%) underwent preoperative biliary drainage (endoscopic stents, percutaneous drains/stents, or surgical drainage). The overall postoperative morbidity rate after pancreaticoduodenectomy was 48% (114/240). Infectious complications occurred in 34% (81/240) of patients. Intraabdominal abscess occurred in 14% (33/240) of patients. The postoperative mortality rate was 5% (12/240). Preoperative biliary drainage was determined to be the only statistically significant variable associated with complications (p = 0.025), infectious complications (p = 0.014), intraabdominal abscess (p = 0.022), and postoperative death (p = 0.037). Preoperative biliary instrumentation alone was not associated with complications, infectious complications, intraabdominal abscess, or postoperative death. Conclusions Preoperative biliary drainage, but not preoperative biliary instrumentation alone, is associated with increased

  3. Expertise modeling for automated planning of acetabular cup in total hip arthroplasty using combined bone and implant statistical atlases.

    PubMed

    Otomaru, Itaru; Kobayashi, Kazuto; Okada, Toshiyuki; Nakamoto, Masahiko; Kagiyama, Yoshiyuki; Takao, Masaki; Sugano, Nobuhiko; Tada, Yukio; Sato, Yoshinobu

    2009-01-01

    Intraoperative robotic and computer-guided assistances are now commonly used in total hip arthroplasty (THA) for accurate execution of the preoperative plan. Although the preoperative plan to be accurately executed is critical, it is still interactively prepared in a time-consuming and subjective manner. In this paper, atlas-based approach to automated surgical planning of the acetabular cup in THA is described to stabilize its quality as well as reduce its time-consuming nature. Surgeon's expertise is embedded in two types of statistical atlases, which are constructed from training datasets of CT-based 3D plans prepared by experienced surgeons. One is a statistical shape model which encodes global spatial relationships between the patient anatomy and implant. The other is the statistical map of residual bone thickness on the implant surface, which encodes local spatial constraints of the anatomy and implant. Given the 3D pelvis shape of the patient, we formulate a procedure to determine the best size and position of the acetabular cup which satisfy the constraints derived from the two statistical atlases. We validated the proposed planning method by retrospective study using the datasets which were actually used in the THA surgery. PMID:20426029

  4. Three-Dimensional Path Planning and Guidance of Leg Vascular Based on Improved Ant Colony Algorithm in Augmented Reality.

    PubMed

    Gao, Ming-ke; Chen, Yi-min; Liu, Quan; Huang, Chen; Li, Ze-yu; Zhang, Dian-hua

    2015-11-01

    Preoperative path planning plays a critical role in vascular access surgery. Vascular access surgery has superior difficulties and requires long training periods as well as precise operation. Yet doctors are on different leves, thus bulky size of blood vessels is usually chosen to undergo surgery and other possible optimal path is not considered. Moreover, patients and surgeons will suffer from X-ray radiation during the surgical procedure. The study proposed an improved ant colony algorithm to plan a vascular optimal three-dimensional path with overall consideration of factors such as catheter diameter, vascular length, diameter as well as the curvature and torsion. To protect the doctor and patient from exposing to X-ray long-term, the paper adopted augmented reality technology to register the reconstructed vascular model and physical model meanwhile, locate catheter by the electromagnetic tracking system and used Head Mounted Display to show the planning path in real time and monitor catheter push procedure. The experiment manifests reasonableness of preoperative path planning and proves the reliability of the algorithm. The augmented reality experiment real time and accurately displays the vascular phantom model, planning path and the catheter trajectory and proves the feasibility of this method. The paper presented a useful and feasible surgical scheme which was based on the improved ant colony algorithm to plan vascular three-dimensional path in augmented reality. The study possessed practical guiding significance in preoperative path planning, intraoperative catheter guiding and surgical training, which provided a theoretical method of path planning for vascular access surgery. It was a safe and reliable path planning approach and possessed practical reference value. PMID:26319273

  5. Preoperative breast marking in reduction mammaplasty.

    PubMed

    Gasperoni, C; Salgarello, M

    1987-10-01

    A simple method of preoperative marking for reduction mammaplasty is described. This method may be used in macromastias when the technique chosen implies a postoperative scar with the shape of an inverted T. The marking sequence follows standard steps, but the drawing is always different because it is a consequence of the shape of the breast. This marking method reduces the chance of making mistakes due to excessive personal evaluations or to the use of standard drawing patterns that may be not suitable for all breast shapes. PMID:3688776

  6. Preoperational test report, recirculation ventilation systems

    SciTech Connect

    Clifton, F.T.

    1997-11-11

    This represents a preoperational test report for Recirculation Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102 and supports the ability to exhaust air from each tank. Each system consists of a valved piping loop, a fan, condenser, and moisture separator; equipment is located inside each respective tank farm in its own hardened building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  7. [Intestinal stoma: preoperative and postoperative management].

    PubMed

    Soravia, C; Beyeler, S; Lataillade, L

    2005-03-01

    The aim of this review is to present the management and indications of intestinal stomas. A stoma induces a body image alteration with important familial and social consequences. A preoperative visit to the stoma nurse prevents technical and/or psychological complications. Stoma nurses, surgeons and general practionners work together to help the patient in his/her new life. New stoma devices have also contributed to improve quality of life. Social and sexual activity can be maintain despite intestinal stoma with appropriate education. PMID:15828375

  8. Diagnostic Laparoscopy in the Pre-operative Assessment of Patients Undergoing Cytoreductive Surgery and HIPEC for Peritoneal Surface Malignancies.

    PubMed

    Seshadri, Ramakrishnan Ayloor; Hemanth Raj E

    2016-06-01

    The introduction of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has led to an improvement in the survival of select patients with peritoneal surface malignancies (PSM). However, it is important to carefully identify patients who will benefit from this procedure and to avoid an unnecessary laparotomy in those who will not. The currently available imaging modalities are unable to accurately predict the peritoneal cancer index (PCI) score or the completeness of cytoreduction. In this article, we review the current status of staging laparoscopy in the assessment of patients with PSM who are planned for CRS & HIPEC. We discuss the patient selection, techniques, complications and efficacy of staging laparoscopy. To summarise, staging laparoscopy is a safe and feasible method of pre-operative assessment of patients with PSM. It has a high sensitivity and positive predictive value in identifying patients who can undergo a complete cytoreduction, thereby preventing many patients from undergoing an unnecessary laparotomy. With the exception of pseudomyxoma peritonei, it should be considered as a part of the routine assessment of patients with PSM who are being considered for CRS & HIPEC. PMID:27065714

  9. Preoperative carbohydrate nutrition reduces postoperative nausea and vomiting compared to preoperative fasting

    PubMed Central

    Yilmaz, Neslihan; Çekmen, Nedim; Bilgin, Ferruh; Erten, Ela; Özhan, Mehmet Özhan; Coşar, Ahmet

    2013-01-01

    Background: The aim of this prospective, randomized, single-blinded study was to compare the effects of a carbohydrate drink 400 mL given 2 h before the surgery with preoperative overnight fasting on the gastric pH and residual volume, postoperative nausea and vomiting (PONV) and antiemetic consumption in patients undergoing laparoscopic cholecystectomy. Materials And Methods: Forty American Society of Anesthesiologists physical status I-II patients who underwent elective laparoscopic cholecystectomy. Randomized, prospective, controlled study, Gulhane Medical Faculty and Guven Hospital Department of Anesthesiology and Reanimation. Patients were randomly assigned into two groups: Pre-operative carbohydrate drink group (group C, n = 20) and preoperative fasting group (group F, n = 20). Group C was given a 400 mL carbohydrate drink 2 h before to the surgery. The patients of group F were fasted 8 h before the surgery. Both groups were operated under general anesthesia with volatile anesthetics. Results: Hemodynamic parameters, demographic data, gastric acidity and residual volumes were similar for both groups. No complications were observed. PONV and antiemetic consumption was lower in group C compared to group F (P = 0.001). Patient's satisfaction was higher in group C (P < 0.001). Conclusion: This study showed that pre-operative carbohydrate drink may be used safely and also improves patient's satisfaction and comfort in patients undergoing laparoscopic cholecystectomy. PMID:24497851

  10. Discordance Between Preoperative and Postoperative Bladder Cancer Location: Implications for Partial-Bladder Radiation

    SciTech Connect

    Goldsmith, Benjamin; Tucker, Kai; Conway, Robert Greg; He, Jiwei; Guzzo, Thomas; Bekelman, Justin; Deville, Curtiland; Vapiwala, Neha; Malkowicz, S. Bruce; Christodouleas, John

    2013-03-01

    Purpose: There is strong interest in partial-bladder radiation whether as a boost or definitive therapy to limit long-term toxicity. It is unclear that a standard preoperative examination can accurately identify all sites of disease within the bladder. The purpose of this study was to determine the correlation between preoperative localization of bladder tumors with postoperative findings to facilitate partial-bladder radiation techniques when appropriate. Methods and Materials: We examined patients with clinically staged T1-T4 invasive transitional cell carcinoma (TCC) or TCC with variant histology with no history of radiation or partial cystectomy undergoing radical cystectomy. Patients were scored as “under-detected” if a bladder site was involved with invasive disease (≥T1) at the time of cystectomy, but not identified preoperatively. Patients were additionally scored as “widely under-detected” if they had postoperative lesions that were not identified preoperatively in a given site, nor in any adjacent site. Rates of under-detected and widely under-detected lesions, as well as univariate and multivariate association between clinical variables and under-detection, were evaluated using logistic regression. Results: Among 222 patients, 96% (213/222) had at least 1 area of discordance. Fifty-eight percent of patients were under-detected in at least 1 location, whereas 12% were widely under-detected. Among 24 patients with a single site of disease on preoperative evaluation, 21/24 (88%) had at least 1 under-detected lesion and 14/24 (58%) were widely under-detected. On multivariate analysis, only solitary site of preoperative disease was associated with increased levels of under-detection of invasive disease (OR = 4.161, 95% CI, 1.368-12.657). Conclusion: Our study shows a stark discordance between preoperative and postoperative localization of bladder tumors. From a clinical perspective, incomplete localization of all sites of disease within the bladder

  11. Preoperative Preparation and Anesthesia for Trabeculectomy

    PubMed Central

    2016-01-01

    ABSTRACT Preoperative preparation should improve the likelihood of successful trabeculectomy surgery. The team can reconsider the appropriateness of the proposed surgery, and steps can be taken to maximize the chance of a good outcome. For example, adjustments to anti-hypertensive or anti-coagulant medications may be made, and topical ocular medications adjusted. Choice of anesthesia technique is of particular relevance to the trabeculectomy patient. Some anesthesia techniques are more likely to have serious complications, and glaucoma patients may be at higher risk of some sight-threatening complications, because the optic nerve is already damaged and vulnerable. Posterior placement of local anesthesia (retrobulbar, peribulbar, posterior sub-Tenon’s techniques) could potentially damage the optic nerve, and thereby cause “wipe-out” of vision. Anesthesia technique may influence the likelihood of vitreous bulge and surgical difficulty. Regarding long-term control of intraocular pressure, there is no good evidence to indicate that any particular anesthesia technique is better than another. There is little high-quality evidence on this topic. The author’s preferred technique for trabeculectomy is subconjunctival-intracameral anesthesia without sedation. How to cite this article: Eke T. Preoperative Preparation and Anesthesia for Trabeculectomy. J Curr Glaucoma Pract 2016; 10(1):21-35. PMID:27231416

  12. Preoperative transarterial Embolisation in bone tumors

    PubMed Central

    Gupta, Pankaj; Gamanagatti, Shivanand

    2012-01-01

    Bone tumors include a variety of lesions, both primary and metastatic. The treatment modalities for bone tumors vary with the individual lesion, but in general surgical excision is the treatment of choice with other adjunctive therapies. However, surgery for many bone tumors is complex due to several factors including tumor bulk, vascularity, vicinity to vital structures and potentially inaccessible location of the lesion. Transarterial Embolisation (TAE) is one of the important adjuvant treatment modalities and in some cases it may be the primary and curative treatment. Preoperative TAE has proved to be effective in both primary and metastatic bone tumors. It reduces tumor vascularity and intraoperative blood loss, the need for blood transfusion and associated complications, allows better definition of tissue planes at surgery affording more complete excision, and hence reduced recurrence. Preoperative chemoEmbolisation has also been shown to increase the sensitivity of some tumors to subsequent chemotherapy and radiotherapy. There are several techniques and embolic agents available for this purpose, but the ultimate aim is to achieve tumor devascularization. In this review, we discuss the techniques including the choice of embolic agent, application to individual lesions and potential complications. PMID:22761978

  13. [Preoperative oral hydration for pregnant women].

    PubMed

    Okutomi, Toshiyuki; Kato, Rie

    2011-07-01

    Preoperative oral hydration is an important component of "enhanced recovery after surgery" strategies. This was originally developed for patients undergoing colon surgery. The Obstetric Anesthesia Practice Guideline issued by American Society of Anesthesiologists states that intake of minimum amount of clear fluid 2 hours prior to surgery may be safe. However, anesthesiologists have to consider physiological changes that parturients undergo during pregnancy, such as increased risk of aspiration and impaired glucose tolerance. We also have to consider the potential effect of glucose loading on neonates. Mothers are more likely to develop ketosis by glucose loading. It also stimulates insulin release in the fetus, which can result in neonatal hypoglycemia. In addition, sodium overloading may deteriorate intra-vascular dehydration and cause lung edema to mothers. On the other hand, oral hydration can alleviate a sense of thirst and increase maternal satisfaction. Our data showed that maternal urinal ketone body at delivery tended to decrease with oral hydration during labor. Moreover, some articles suggest that oral hydration may improve utero-placental perfusion. Therefore, we have to balance risks and benefits of oral hydration in parturients. Further investigations are needed among this specific subgroup of patients in order to establish the safe application of preoperative oral hydration. PMID:21800658

  14. [Preoperative chemoradiotherapy for resectable lower rectal cancer].

    PubMed

    Takase, Shiro; Kamigaki, Takashi; Yamashita, Kimihiro; Nakamura, Tetsu; Nishimura, Hideki; Sasaki, Ryohei

    2009-11-01

    To suppress local recurrence and preserve sphincter function, we performed preoperative chemoradiotherapy( CRT) of rectal cancer. Sixteen patients with lower advanced rectal cancer received tegafur/uracil/calcium folinate+RT followed by curative resection with lateral lymph node dissection 2-8 weeks later. The male/female ratio was found to be 11:5 (41-75 years old) and the CRT was feasible for all patients. There were 11-PR and 5-SD according to RECIST criteria, and lower isotope accumulation was observed for all primary tumors in FDG-PET study. After CRT, all patients received R0 curative resection (11 APR, 2 LAR, 1 Hartmann and 1 ISR). On pathological study, 3 patients showed complete response. Surgical complications including pelvic infection, delayed a wound healing and deep venous thrombosis, etc. In conclusion, preoperative CRT of advanced rectal cancer could potentially be useful for local control and sphincter saving, however, it is necessary to manage specific surgical complications due to radiation. PMID:20037306

  15. Bevacizumab with preoperative chemotherapy versus preoperative chemotherapy alone for colorectal cancer liver metastases

    PubMed Central

    Lu, Zhen-Hai; Peng, Jian-Hong; Wang, Fu-Long; Yuan, Yun-Fei; Jiang, Wu; Li, Yu-Hong; Wu, Xiao-Jun; Chen, Gong; Ding, Pei-Rong; Li, Li-Ren; Kong, Ling-Heng; Lin, Jun-Zhong; Zhang, Rong-Xin; Wan, De-Sen; Pan, Zhi-Zhong

    2016-01-01

    Abstract This study aimed to assess the efficacy and safety of bevacizumab plus preoperative chemotherapy as first-line treatment for liver-only metastatic colorectal cancer in Chinese patients compared with those of preoperative chemotherapy alone. Patients with histologically confirmed liver-only metastatic colorectal cancer were sequentially reviewed, and received either preoperative chemotherapy plus bevacizumab (bevacizumab group, n = 32) or preoperative chemotherapy alone (chemotherapy group, n = 57). Progression-free survival, response rate, liver resection rate, conversion rate, and safety were analyzed. With median follow-up of 28.7 months, progression-free survival was 10.9 months (95% confidence interval: 8.7–13.1 months) in bevacizumab group and 9.9 months (95% confidence interval: 6.8–13.1 months) in chemotherapy group (P = 0.472). Response rates were 59.4% in bevacizumab group and 38.6% in chemotherapy group (P = 0.059). Overall liver resection (R0, R1, and R2) rate was 68.8% in bevacizumab group and 54.4% in chemotherapy group (P = 0.185). Conversion rate was 51.9% in bevacizumab group and 40.4% in chemotherapy group (P = 0.341). No postoperative complication was observed in all patients. Bevacizumab plus preoperative chemotherapy as first-line treatment for liver-only metastatic colorectal cancer tends to achieve better clinical benefit with controllable safety in Chinese patients. PMID:27583930

  16. Jejunioleal Bypass Procedures in Morbid Obesity: Preoperative Psychological Findings

    ERIC Educational Resources Information Center

    Webb, Warren W.; And Others

    1976-01-01

    Seventy patients who averaged 155 percent overweight and requested jejunioleal bypass surgery as a treatment intervention for morbid obesity were studied preoperatively for prominent psychological characteristics. (Author)

  17. An evaluation of factors influencing the assessment time in a nurse practitioner-led anaesthetic pre-operative assessment clinic.

    PubMed

    Hawes, R H; Andrzejowski, J C; Goodhart, I M; Berthoud, M C; Wiles, M D

    2016-03-01

    Elective patients undergoing anaesthetic pre-operative assessment are usually allocated the same period of time with a nurse practitioner, leading to potential inefficiencies in patient flow through the clinic. We prospectively collected data on 8519 patients attending a pre-operative assessment clinic. The data set were split into derivation and validation cohorts. Standard multiple regressions were used to construct a model in the derivation cohort, which was then tested in the validation cohort. Due to missing data, 2457 patients were not studied, leaving 5892 for analysis (3870 in the derivation cohort and 2022 in the validation cohort). The mean (SD) pre-operative assessment time was 46 (12) min. Age, ASA physical status, nurse practitioner and surgical specialty all influenced the time spent in pre-operative assessment. The predictive equations calculated using the derivation cohort, based on age and ASA physical status, correctly estimated duration of consultation to within 20% of the maximum predicted time in 74.2% of the validation cohort. We conclude that if age and ASA physical status are known before the pre-operative assessment consultation, it could allow appointment times to be allocated more accurately. PMID:26684961

  18. Usefulness of Preoperative Assessment of Perigastric Vascular Anatomy by Dynamic Computed Tomography for Laparoscopic Gastrectomy

    PubMed Central

    Osaki, Tomohiro; Saito, Hiroaki; Murakami, Yuki; Miyatani, Kozo; Kuroda, Hirohiko; Matsunaga, Tomoyuki; Fukumoto, Youji; Ikeguchi, Masahide

    2015-01-01

    Background Laparoscopic surgery requires a more detailed understanding of local anatomy than does conventional open surgery. The aim of this study was to examine the usefulness of dynamic computed tomography (D-CT) for identification of the location of the left gastric vein (LGV) and existence of the aberrant left hepatic artery (ALHA) compared with conventional enhanced computed tomography (E-CT). Methods Sixty-eight patients underwent laparoscopic-assisted gastrectomy (LAG). E-CT and D-CT were performed in 32 and 36 patients, respectively, and three-dimensional computed tomographic angiography (3D-CTA) was performed in addition to D-CT. The location of the LGV and existence of the ALHA were confirmed during LAG, and these results were compared with those determined preoperatively by CT imaging. Results The location of the LGV as detected by preoperative E-CT and D-CT was consistent with that identified during LAG in 28 (87.5%) and 31 (88.9%) patients, respectively, with no statistical differences. The existence of the ALHA as detected by preoperative E-CT and D-CT was consistent with that identified during gastrectomy in 24 (75%) and 36 (100%) patients, respectively, with a statistical difference (P = 0.005). Furthermore, the type of ALHA could be identified in 10 of 12 patients (83.3%) by D-CT. Conclusion D-CT can produce excellent images of the vascular supply, and thus undoubtedly contributes to the preoperative planning of LAG. Preoperative D-CT might be an informative tool with which to help overcome the disadvantages of LAG. PMID:26740734

  19. Comparison of pre/post-operative CT image volumes to preoperative digitization of partial hepatectomies: a feasibility study in surgical validation

    NASA Astrophysics Data System (ADS)

    Dumpuri, Prashanth; Clements, Logan W.; Li, Rui; Waite, Jonathan M.; Stefansic, James D.; Geller, David A.; Miga, Michael I.; Dawant, Benoit M.

    2009-02-01

    Preoperative planning combined with image-guidance has shown promise towards increasing the accuracy of liver resection procedures. The purpose of this study was to validate one such preoperative planning tool for four patients undergoing hepatic resection. Preoperative computed tomography (CT) images acquired before surgery were used to identify tumor margins and to plan the surgical approach for resection of these tumors. Surgery was then performed with intraoperative digitization data acquire by an FDA approved image-guided liver surgery system (Pathfinder Therapeutics, Inc., Nashville, TN). Within 5-7 days after surgery, post-operative CT image volumes were acquired. Registration of data within a common coordinate reference was achieved and preoperative plans were compared to the postoperative volumes. Semi-quantitative comparisons are presented in this work and preliminary results indicate that significant liver regeneration/hypertrophy in the postoperative CT images may be present post-operatively. This could challenge pre/post operative CT volume change comparisons as a means to evaluate the accuracy of preoperative surgical plans.

  20. Preoperational test report, recirculation condenser cooling systems

    SciTech Connect

    Clifton, F.T.

    1997-11-04

    This represents a preoperational test report for Recirculation Condenser Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The four system provide condenser cooling water for vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102. Each system consists of a valved piping loop, a pair of redundant recirculation pumps, a closed-loop evaporative cooling tower, and supporting instrumentation; equipment is located outside the farm on concrete slabs. Piping is routed to the each ventilation condenser inside the farm via below-grade concrete trenches. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  1. Pre-operative optimisation of lung function

    PubMed Central

    Azhar, Naheed

    2015-01-01

    The anaesthetic management of patients with pre-existing pulmonary disease is a challenging task. It is associated with increased morbidity in the form of post-operative pulmonary complications. Pre-operative optimisation of lung function helps in reducing these complications. Patients are advised to stop smoking for a period of 4–6 weeks. This reduces airway reactivity, improves mucociliary function and decreases carboxy-haemoglobin. The widely used incentive spirometry may be useful only when combined with other respiratory muscle exercises. Volume-based inspiratory devices have the best results. Pharmacotherapy of asthma and chronic obstructive pulmonary disease must be optimised before considering the patient for elective surgery. Beta 2 agonists, inhaled corticosteroids and systemic corticosteroids, are the main drugs used for this and several drugs play an adjunctive role in medical therapy. A graded approach has been suggested to manage these patients for elective surgery with an aim to achieve optimal pulmonary function. PMID:26556913

  2. Pancoast tumors: characteristics and preoperative assessment

    PubMed Central

    Panagopoulos, Nikolaos; Leivaditis, Vasilios; Koletsis, Efstratios; Prokakis, Christos; Alexopoulos, Panagiotis; Baltayiannis, Nikolaos; Hatzimichalis, Antonios; Tsakiridis, Kosmas; Zarogoulidis, Konstantinos; Katsikogiannis, Nikolaos; Kougioumtzi, Ioanna; Machairiotis, Nikolaos; Tsiouda, Theodora; Kesisis, Georgios; Siminelakis, Stavros; Madesis, Athanasios; Dougenis, Dimitrios

    2014-01-01

    Superior sulcus tumors (SSTs), or as otherwise known Pancoast tumors, make up a clinically unique and challenging subset of non-small cell carcinoma of the lung (NSCLC). Although the outcome of patients with this disease has traditionally been poor, recent developments have contributed to a significant improvement in prognosis of SST patients. The combination of severe and unrelenting shoulder and arm pain along the distribution of the eighth cervical and first and second thoracic nerve trunks, Horner’s syndrome (ptosis, miosis, and anhidrosis) and atrophy of the intrinsic hand muscles comprises a clinical entity named as “Pancoast-Tobias syndrome”. Apart NSCLC, other lesions may, although less frequently, result in Pancoast syndrome. In the current review we will present the main characteristics of the disease and focus on the preoperative assessment. PMID:24672686

  3. Effect of Smoking on Joint Replacement Outcomes: Opportunities for Improvement Through Preoperative Smoking Cessation.

    PubMed

    Wright, Erik; Tzeng, Tony H; Ginnetti, Michael; El-Othmani, Mouhanad M; Saleh, Jamal K; Saleh, Jasmine; Lane, J M; Mihalko, William M; Saleh, Khaled J

    2016-01-01

    Because orthopaedic surgeons focus on identifying serious potential complications, such as heart attack, stroke, and deep vein thrombosis, during the preoperative assessment, correctable factors, such as smoking, may be overlooked. Chronic exposure to nicotine has been correlated with perioperative complications that lead to worse outcomes, including decreased patient satisfaction, longer hospitalization periods, and an increased rate of hospital readmission. It has been proven that smoking is a negative risk factor for decreased bone mineral density, which leads to increased fracture risk, heightened pain, postoperative wound and bone healing complications, decreased fusion rates, and postoperative tendon and ligament healing complications. Physician-led preoperative smoking cessation programs that include, but are not limited to, pharmacotherapy plans have been shown to improve primary surgical outcomes and smoking cessation rates. Smoking has detrimental effects on specialty-specific physiology; however, there are many effective options for intervention that can improve primary outcomes. PMID:27049216

  4. Pre-operative nutrition and carbohydrate loading.

    PubMed

    Kratzing, Caroline

    2011-08-01

    An optimal nutritional state is an important consideration in providing successful operative outcomes. Unfortunately, many aspects of surgery are not constructive to providing this. In addition, the metabolic and immune response to injury induces a catabolic state and insulin resistance, a known risk factor of post-operative complications. Aggressive insulin therapy post-operatively has been shown to reduce morbidity and mortality but similar results can be achieved when insulin resistance is lessened by the use of pre-operative carbohydrate loading. Consuming carbohydrate-containing drinks up to 2 h before surgery has been found to be an effective way to attenuate insulin resistance, minimise protein losses, reduce hospital stays and improve patient comfort without adversely affecting gastric emptying. Enhanced recovery programmes have employed carbohydrate loading as one of several strategies aimed at reducing post-operative stress and improving the recovery process. Studies examining the benefits of these programmes have demonstrated significantly shorter post-operative hospital stays, faster return to normal functions and lower occurrences of surgical complications. As a consequence of the favourable evidence they are now being implemented in many surgical units. Further benefit to post-operative recovery may be found with the use of immune-enhancing diets, i.e. supplementation with n-3 fatty acids, arginine, glutamine and/or nucleotides. These have the potential to boost the immune system, improve wound healing and reduce inflammatory markers. Research exploring the benefits of immunonutrition and solidifying the use of carbohydrate loading is ongoing; however, there is strong evidence to link good pre-operative nutrition and improved surgical outcomes. PMID:21781358

  5. Prevention and Intervention Strategies to Alleviate Preoperative Anxiety in Children

    ERIC Educational Resources Information Center

    Wright, Kristi D.; Stewart, Sherry H.; Finley, G. Allen; Buffett-Jerrott, Susan E.

    2007-01-01

    Preoperative anxiety (anxiety regarding impending surgical experience) in children is a common phenomenon that has been associated with a number of negative behaviors during the surgery experience (e.g., agitation, crying, spontaneous urination, and the need for physical restraint during anesthetic induction). Preoperative anxiety has also been…

  6. Preoperative diagnosis of double gallbladder: a case report.

    PubMed

    Buluş, Hakan; Koyuncu, Ahmet; Coşkun, Ali

    2012-04-01

    Gallbladder duplication is a rare congenital anomaly of the biliary system. There are no specific symptoms for diagnosis. We present the case of a double gallbladder, which was diagnosed preoperatively. A laparoscopic cholecystectomy was performed successfully. We discuss that the preoperative diagnosis of this anomaly is especially important to prevent possible surgical complications and repeated laparotomies. PMID:22706748

  7. Utility of preoperative imaging in evaluating colorectal liver metastases declines over time

    PubMed Central

    Yang, Simon; Hongjinda, Sermsak; Hanna, Sherif S; Gallinger, Steven; Wei, Alice C; Kiss, Alex; Law, Calvin

    2010-01-01

    Objectives Reports on the sensitivity and accuracy of contrast-enhanced helical computed tomography (HCT) in the preoperative evaluation of colorectal liver metastases (CLM) have been conflicting. Few studies have controlled for and reported on the time interval between HCT and eventual surgery. Methods A multi-institution, retrospective review of consecutive patients who underwent hepatic resection for CLM from January 1999 to September 2004 was conducted. Data regarding lesion characteristics and resectability were extracted from radiology reports, operative findings and histopathological records. Findings in HCT were evaluated according to their sensitivity for detecting CLM and ability to predict resectability. Results A total of 217 consecutive patients who underwent hepatic resection for CLM were identified. The overall sensitivity of HCT for detection of CLM was 83.2%. Prolonged time between imaging and surgery was a negative predictor for HCT sensitivity in univariate and multivariate analysis (P < 0.001). In predicting resectability, preoperative HCT was accurate 77.0% of the time. The time interval to surgery was negatively correlated with HCT prediction accuracy in univariate and multivariate analyses (P < 0.001). Conclusions The utility of HCT as a preoperative tool to evaluate CLM is inversely proportional to the time interval between imaging and surgery. This may explain conflicting reports of the accuracy of HCT in the current literature. PMID:20961368

  8. Hemostatic status in liver transplantation: association between preoperative procoagulants/anticoagulants and postoperative hemorrhaging/thrombosis.

    PubMed

    Akamatsu, Nobuhisa; Sugawara, Yasuhiko; Nakazawa, Akiko; Nishioka, Yujiro; Kaneko, Junichi; Aoki, Taku; Sakamoto, Yoshihiro; Hasegawa, Kiyoshi; Kokudo, Norihiro

    2015-02-01

    The delicate rebalanced hemostatic status of liver transplant recipients may lead to both hemorrhagic and thrombotic tendencies in this population. The aim of this study was to investigate the association between pretransplant procoagulants/anticoagulants and posttransplant bleeding and thrombosis among living donor liver transplant recipients. The study subjects were 403 consecutive recipients with chronic liver disease. Perioperative variables, including preoperative values for procoagulants and anticoagulants, were assessed to determine their association with posttransplant hemorrhaging and thrombosis. There were 35 hemorrhagic complications (9%) and 21 thrombotic complications (5%). In logistic regression analyses, a higher Model for End-Stage Liver Disease score (P = 0.01) and a lower fibrinogen value (P < 0.001) were independently associated with hemorrhaging, whereas only a lower protein C value (P < 0.001) was independently associated with thrombosis. In a receiver operating characteristic analysis, a low preoperative protein C value (with the most accurate cutoff value being 25%) was a reliable predictor of thrombotic complications after liver transplantation (area under the curve = 0.921, P < 0.001, sensitivity = 0.9, specificity = 0.8). In conclusion, the decreases in both procoagulants and anticoagulants in liver transplant recipients may additively result in a delicate hemostatic balance and predispose patients to both hemorrhagic and thrombotic complications. A lower preoperative protein C value (<25%) was demonstrated to be a significant and reliable predictor of postoperative thrombotic complications in liver transplant recipients. PMID:25370801

  9. Predictive value of fine needle aspiration biopsy of axillary lymph nodes in preoperative breast cancer staging

    PubMed Central

    Akıncı, Muzaffer; Bulut, Serap Pamak; Erözgen, Fazilet; Gürbüzel, Mihriban; Gülşen, Gökçe; Kocakuşak, Ahmet; Gülen, Mehmet; Kaplan, Rafet

    2016-01-01

    Objective Diagnosis of axillary nodal involvement is significant in the management of breast cancer as well as in predicting prognosis. In this prospective study, we evaluated the efficiency of US-guided fine needle aspiration biopsy (FNAB) in preoperative axillary staging of early breast cancer. Material and Methods Between January 2011 and July 2013, 46 women were prospectively enrolled in the study. Ultrasound guided-FNABs for axillary assessment were performed preoperatively. Cytology results were compared with histopathology reports to determine its sensitivity, specificity, negative and positive predictive value and accuracy. Results Nineteen cases that had malignant cytology on FNAB also had axillary involvement in axillary lymph node dissection (ALND) without any false-positive results. The sensitivity and specificity of US-guided FNAB were 63.3% and 100%, respectively. US-guided FNAB was accurate in predicting the status of the axilla in 76.1% of patients. Conclusion Although this technique is favorable due to its minimally invasive nature, it is not as effective as sentinel lymph node biopsy (SLNB) in terms of detecting axillary metastasis preoperatively. The low sensitivity and low accuracy rates decrease the usefulness of the technique. Therefore, it seems that US-guided FNAB alone could not replace SLNB. Nevertheless, combining some other molecular studies may be useful in increasing the technique’s sensitivity. These issues should be determined by comprehensive clinical trials. PMID:27528822

  10. Evaluation of surgical outcome, complications, and mortality in dogs undergoing preoperative computed tomography angiography for diagnosis of an extrahepatic portosystemic shunt: 124 cases (2005–2014)

    PubMed Central

    Brunson, Benjamin W.; Case, J. Brad; Ellison, Gary W.; Fox-Alvarez, W. Alexander; Kim, Stanley E.; Winter, Matthew; Garcia-Pereira, Fernando L.; Farina, Lisa L.

    2016-01-01

    This study evaluated the safety of preoperative computed tomography angiography (CTA) and its effect on surgical time and clinical outcomes in dogs that underwent surgical correction of a single congenital extrahepatic portosystemic shunt (CEPSS). Patient data were retrospectively collected from medical records and owner communications for 124 dogs with single CEPSS, undergoing preoperative CTA (n = 43) or not (n = 81) which were surgically treated from 2005 to 2014. The frequency of major postoperative complications was 4.7% and 9.9% for the CTA and no CTA groups, respectively (P = 0.49). Mean ± standard deviation (SD) surgical time for the preoperative CTA group was 84 ± 40 min and 81 ± 31 min for the no CTA group (P = 0.28). We conclude that anesthetized preoperative CTA appears to be a safe method for diagnosis and surgical planning in dogs with single CEPSS, and does not appear to affect surgical procedure time, complication rate, or clinical outcome. PMID:26740699

  11. Diagnosing, planning and evaluating osteochondral ankle defects with imaging modalities.

    PubMed

    van Bergen, Christiaan Ja; Gerards, Rogier M; Opdam, Kim Tm; Terra, Maaike P; Kerkhoffs, Gino Mmj

    2015-12-18

    This current concepts review outlines the role of different imaging modalities in the diagnosis, preoperative planning, and follow-up of osteochondral ankle defects. An osteochondral ankle defect involves the articular cartilage and subchondral bone (usually of the talus) and is mostly caused by an ankle supination trauma. Conventional radiographs are useful as an initial imaging tool in the diagnostic process, but have only moderate sensitivity for the detection of osteochondral defects. Computed tomography (CT) and magnetic resonance imaging (MRI) are more accurate imaging modalities. Recently, ultrasonography and single photon emission CT have been described for the evaluation of osteochondral talar defects. CT is the most valuable modality for assessing the exact location and size of bony lesions. Cartilage and subchondral bone damage can be visualized using MRI, but the defect size tends to be overestimated due to bone edema. CT with the ankle in full plantar flexion has been shown a reliable tool for preoperative planning of the surgical approach. Postoperative imaging is useful for objective assessment of repair tissue or degenerative changes of the ankle joint. Plain radiography, CT and MRI have been used in outcome studies, and different scoring systems are available. PMID:26716090

  12. Diagnosing, planning and evaluating osteochondral ankle defects with imaging modalities

    PubMed Central

    van Bergen, Christiaan JA; Gerards, Rogier M; Opdam, Kim TM; Terra, Maaike P; Kerkhoffs, Gino MMJ

    2015-01-01

    This current concepts review outlines the role of different imaging modalities in the diagnosis, preoperative planning, and follow-up of osteochondral ankle defects. An osteochondral ankle defect involves the articular cartilage and subchondral bone (usually of the talus) and is mostly caused by an ankle supination trauma. Conventional radiographs are useful as an initial imaging tool in the diagnostic process, but have only moderate sensitivity for the detection of osteochondral defects. Computed tomography (CT) and magnetic resonance imaging (MRI) are more accurate imaging modalities. Recently, ultrasonography and single photon emission CT have been described for the evaluation of osteochondral talar defects. CT is the most valuable modality for assessing the exact location and size of bony lesions. Cartilage and subchondral bone damage can be visualized using MRI, but the defect size tends to be overestimated due to bone edema. CT with the ankle in full plantar flexion has been shown a reliable tool for preoperative planning of the surgical approach. Postoperative imaging is useful for objective assessment of repair tissue or degenerative changes of the ankle joint. Plain radiography, CT and MRI have been used in outcome studies, and different scoring systems are available. PMID:26716090

  13. Plan to procedure: combining 3D templating with rapid prototyping to enhance pedicle screw placement

    NASA Astrophysics Data System (ADS)

    Augustine, Kurt E.; Stans, Anthony A.; Morris, Jonathan M.; Huddleston, Paul M.; Matsumoto, Jane M.; Holmes, David R., III; Robb, Richard A.

    2010-02-01

    Spinal fusion procedures involving the implantation of pedicle screws have steadily increased over the past decade because of demonstrated improvement in biomechanical stability of the spine. However, current methods of spinal fusion carries a risk of serious vascular, visceral, and neurological injury caused by inaccurate placement or inappropriately sized instrumentation, which may lead to patient paralysis or even fatality. 3D spine templating software developed by the Biomedical Imaging Resource (BIR) at Mayo Clinic allows the surgeon to virtually place pedicle screws using pre-operative 3D CT image data. With the template plan incorporated, a patient-specific 3D anatomic model is produced using a commercial rapid prototyping system. The pre-surgical plan and the patient-specific model then are used in the procedure room to provide real-time visualization and quantitative guidance for accurate placement of each pedicle screw, significantly reducing risk of injury. A pilot study was conducted at Mayo Clinic by the Department of Radiology, the Department of Orthopedics, and the BIR, involving seven complicated pediatric spine cases. In each case, pre-operative 3D templating was carried out and patient specific models were generated. The plans and the models were used intra-operatively, providing precise pedicle screw starting points and trajectories. Postoperative assessment by the surgeon confirmed all seven operations were successful. Results from the study suggest that patient-specific, 3D anatomic models successfully acquired from 3D templating tools are valuable for planning and conducting pedicle screw insertion procedures.

  14. Preoperative optimization of the vascular surgery patient.

    PubMed

    Zhan, Henry T; Purcell, Seth T; Bush, Ruth L

    2015-01-01

    It is well known that patients who suffer from peripheral (noncardiac) vascular disease often have coexisting atherosclerotic diseases of the heart. This may leave the patients susceptible to major adverse cardiac events, including death, myocardial infarction, unstable angina, and pulmonary edema, during the perioperative time period, in addition to the many other complications they may sustain as they undergo vascular surgery procedures, regardless of whether the procedure is performed as an open or endovascular modality. As these patients are at particularly high risk, up to 16% in published studies, for postoperative cardiac complications, many proposals and algorithms for perioperative optimization have been suggested and studied in the literature. Moreover, in patients with recent coronary stents, the risk of non-cardiac surgery on adverse cardiac events is incremental in the first 6 months following stent implantation. Just as postoperative management of patients is vital to the outcome of a patient, preoperative assessment and optimization may reduce, and possibly completely alleviate, the risks of major postoperative complications, as well as assist in the decision-making process regarding the appropriate surgical and anesthetic management. This review article addresses several tools and therapies that treating physicians may employ to medically optimize a patient before they undergo noncardiac vascular surgery. PMID:26170688

  15. Preoperative Computed Tomography Findings for Patients with Nasolacrimal Duct Obstruction or Stenosis

    PubMed Central

    Choi, Seong Chan; Lee, Saem; Choi, Hye Sun; Jang, Jae Woo; Kim, Sung Joo

    2016-01-01

    Purpose To identify and analyze the role of preoperative computed tomography (CT) in patients with tearing symptoms with nasolacrimal duct obstruction (NLDO). Methods We retrospectively reviewed the medical records and CT results on 218 patients who complained of tearing symptoms with NLDO between January 2014 and December 2014. All patients were recruited from Kim's Eye Hospital's outpatient clinic and assessed by clinical history, examination, and CT to evaluate periocular pathology and nasolacrimal drainage system. Patients with abnormal findings assessed by preoperative CT were further reviewed. Results CT was performed on 218 patients (average age, 58.2 ± 11.9 years). Of these, 196 (89.9%) had endonasal dacryocystorhinostomy, 14 (6.4%) declined surgery, and 8 (3.7%) were inoperable due to abnormal CT findings. Soft tissue opacity was the most common finding which 243 cases (85.9%) of 283 obstructed nasolacrimal duct and 89 cases (81.7%) of 109 non-obstructed nasolacrimal duct showed it. Thirty-nine (17.8%) of 218 patients showed either maxillary sinusitis or ethmoidal sinusitis and 32 (14.7%) of 218 patients presented with periocular inflammation. Other abnormal CT findings included septal deviations, previous fractures, masses, and structural abnormalities of nasal cavity. Conclusions Preoperative CT imaging is useful in the assessment of both nasolacrimal drainage and nearby anatomical structures. This information will be helpful in planning surgical interventions and management of NLDO. PMID:27478350

  16. Preoperative radiotherapy for rectal adenocarcinoma: Which are strong prognostic factors?

    SciTech Connect

    Chapet, Olivier . E-mail: ochapet@med.umich.edu; Romestaing, Pascale; Mornex, Francoise; Souquet, Jean-Christophe; Favrel, Veronique; Ardiet, Jean-Michel; D'Hombres, Anne; Gerard, Jean-Pierre

    2005-04-01

    Purpose: This retrospective 12-year study evaluated the prognostic value of initial and postoperative staging of rectal tumors. Methods and Materials: Between 1985 and 1996, 297 patients were treated with preoperative radiotherapy (39 Gy in 13 fractions) and surgery for Stage T2-T4N0-N1M0 rectal adenocarcinoma. Pretreatment staging included a clinical examination and endorectal ultrasonography (EUS) since 1988. Clinical staging was performed by digital rectal examination and rigid proctoscopy. EUS was performed in 236 patients. Postoperative staging was performed by examination of the pathologic specimen. Results: The median follow-up was 49 months. The overall 5-year survival rate was 67%, with a local failure rate of 9%. The rate of sphincter preservation was 65%. The clinical examination findings were strong prognostic factor for both cT stage (p < 0.001) and cN stage (p < 0.006) but had poor specificity for cN stage (only 25 lymph nodes detected). In both univariate and multivariate analyses, EUS had a statistically significant prognostic value for uT (p < 0.014) but not for uN (p < 0.47) stage. In contrast, pT and pN stages were strong prognostic factors (p < 0.001 and p < 0.001, respectively). Conclusion: Pretreatment staging, including clinical examination and EUS, seemed accurate enough to present a high prognostic value for the T stage. EUS was insufficient to stage lymph node involvement. Owing to its lack of specificity, uN stage was not a reliable prognostic factor. An improvement in N staging is necessary and essential. Despite downstaging, postoperative staging remained a very strong prognostic factor for both T and N stages.

  17. Intensity-Modulated Radiation Therapy With Concurrent Chemotherapy as Preoperative Treatment for Localized Gastric Adenocarcinoma

    SciTech Connect

    Chakravarty, Twisha; Crane, Christopher H.; Ajani, Jaffer A.; Mansfield, Paul F.; Briere, Tina M.; Beddar, A. Sam; Mok, Henry; Reed, Valerie K.; Krishnan, Sunil; Delclos, Marc E.; Das, Prajnan

    2012-06-01

    Purpose: The goal of this study was to evaluate dosimetric parameters, acute toxicity, pathologic response, and local control in patients treated with preoperative intensity-modulated radiation therapy (IMRT) and concurrent chemotherapy for localized gastric adenocarcinoma. Methods: Between November 2007 and April 2010, 25 patients with localized gastric adenocarcinoma were treated with induction chemotherapy, followed by preoperative IMRT and concurrent chemotherapy and, finally, surgical resection. The median radiation therapy dose was 45 Gy. Concurrent chemotherapy was 5-fluorouracil and oxaliplatin in 18 patients, capecitabine in 3, and other regimens in 4. Subsequently, resection was performed with total gastrectomy in 13 patients, subtotal gastrectomy in 7, and other surgeries in 5. Results: Target coverage, expressed as the ratio of the minimum dose received by 99% of the planning target volume to the prescribed dose, was a median of 0.97 (range, 0.92-1.01). The median V{sub 30} (percentage of volume receiving at least 30 Gy) for the liver was 26%; the median V{sub 20} (percentage of volume receiving at least 20 Gy) for the right and left kidneys was 14% and 24%, respectively; and the median V{sub 40} (percentage of volume receiving at least 40 Gy) for the heart was 18%. Grade 3 acute toxicity developed in 14 patients (56%), including dehydration in 10, nausea in 8, and anorexia in 5. Grade 4 acute toxicity did not develop in any patient. There were no significant differences in the rates of acute toxicity, hospitalization, or feeding tube use in comparison to those in a group of 50 patients treated with preoperative three-dimensional conformal radiation therapy with concurrent chemotherapy. R0 resection was obtained in 20 patients (80%), and pathologic complete response occurred in 5 (20%). Conclusions: Preoperative IMRT for gastric adenocarcinoma was well tolerated, accomplished excellent target coverage and normal structure sparing, and led to appropriate

  18. Multimodality assessment of esophageal cancer: preoperative staging and monitoring of response to therapy.

    PubMed

    Kim, Tae Jung; Kim, Hyae Young; Lee, Kyung Won; Kim, Moon Soo

    2009-01-01

    Esophageal cancer is a leading cause of cancer mortality worldwide. Complete resection of esophageal cancer and adjacent malignant lymph nodes is the only potentially curative treatment. Accurate preoperative staging and assessment of therapeutic response after neoadjuvant therapy are crucial in determining the most suitable therapy and avoiding inappropriate attempts at curative surgery. Computed tomography (CT) is recommended for initial imaging following confirmation of malignancy at pathologic analysis, primarily to rule out unresectable or distant metastatic disease. With the advent of multidetector CT, use of thin sections and multiplanar reformation allows more accurate staging of esophageal cancer. Endoscopic ultrasonography (US) is the best modality for determining the depth of tumor invasion and presence of regional lymph node involvement. Combined use of fine-needle aspiration and endoscopic US can improve assessment of lymph node involvement. Positron emission tomography (PET) is useful for assessment of distant metastases but is not appropriate for detecting and staging primary tumors. PET may also be helpful in restaging after neoadjuvant therapy, since it allows identification of early response to treatment and detection of interval distant metastases. Each imaging modality has its advantages and disadvantages; therefore, CT, endoscopic US, and PET should be considered complementary modalities for preoperative staging and therapeutic monitoring of patients with esophageal cancer. PMID:19325056

  19. Preoperative Evaluation with fMRI of Patients with Intracranial Gliomas

    PubMed Central

    Kapsalakis, Ioannis Z.; Kapsalaki, Eftychia Z.; Gotsis, Efstathios D.; Verganelakis, Dimitrios; Toulas, Panagiotis; Hadjigeorgiou, Georgios; Chung, Indug; Fezoulidis, Ioannis; Papadimitriou, Alexandros; Robinson, Joe Sam; Lee, Gregory P.; Fountas, Kostas N.

    2012-01-01

    Introduction. Aggressive surgical resection constitutes the optimal treatment for intracranial gliomas. However, the proximity of a tumor to eloquent areas requires exact knowledge of its anatomic relationships to functional cortex. The purpose of our study was to evaluate fMRI's accuracy by comparing it to intraoperative cortical stimulation (DCS) mapping. Material and Methods. Eighty-seven patients, with presumed glioma diagnosis, underwent preoperative fMRI and intraoperative DCS for cortical mapping during tumor resection. Findings of fMRI and DCS were considered concordant if the identified cortical centers were less than 5 mm apart. Pre and postoperative Karnofsky Performance Scale and Spitzer scores were recorded. A postoperative MRI was obtained for assessing the extent of resection. Results. The areas of interest were identified by fMRI and DCS in all participants. The concordance between fMRI and DCS was 91.9% regarding sensory-motor cortex, 100% for visual cortex, and 85.4% for language. Data analysis showed that patients with better functional condition demonstrated higher concordance rates, while there also was a weak association between tumor grade and concordance rate. The mean extent of tumor resection was 96.7%. Conclusions. Functional MRI is a highly accurate preoperative methodology for sensory-motor mapping. However, in language mapping, DCS remains necessary for accurate localization. PMID:22848821

  20. NNLOPS accurate associated HW production

    NASA Astrophysics Data System (ADS)

    Astill, William; Bizon, Wojciech; Re, Emanuele; Zanderighi, Giulia

    2016-06-01

    We present a next-to-next-to-leading order accurate description of associated HW production consistently matched to a parton shower. The method is based on reweighting events obtained with the HW plus one jet NLO accurate calculation implemented in POWHEG, extended with the MiNLO procedure, to reproduce NNLO accurate Born distributions. Since the Born kinematics is more complex than the cases treated before, we use a parametrization of the Collins-Soper angles to reduce the number of variables required for the reweighting. We present phenomenological results at 13 TeV, with cuts suggested by the Higgs Cross section Working Group.

  1. Reducing preoperative fasting time: A trend based on evidence

    PubMed Central

    de Aguilar-Nascimento, José Eduardo; Dock-Nascimento, Diana Borges

    2010-01-01

    Preoperative fasting is mandatory before anesthesia to reduce the risk of aspiration. However, the prescribed 6-8 h of fasting is usually prolonged to 12-16 h for various reasons. Prolonged fasting triggers a metabolic response that precipitates gluconeogenesis and increases the organic response to trauma. Various randomized trials and meta-analyses have consistently shown that is safe to reduce the preoperative fasting time with a carbohydrate-rich drink up to 2 h before surgery. Benefits related to this shorter preoperative fasting include the reduction of postoperative gastrointestinal discomfort and insulin resistance. New formulas containing amino acids such as glutamine and other peptides are being studied and are promising candidates to be used to reduce preoperative fasting time. PMID:21160851

  2. Diversity in preoperative-assessment data collection, a literature review.

    PubMed

    Ahmadian, Leila; Cornet, Ronald; van Klei, Wilton A; de Keizer, Nicolette F

    2008-01-01

    The appropriate anesthetic techniques and care during and after operation rely on data gathered during the preoperative assessment. Because various people are involved, standardization of this process is important. This paper provides a systematic literature review about which data items are collected in the preoperative assessment. Thirty-two relevant articles were found by PubMed search. To categorize data SNOMED CT concepts are used, resulting in 13 categories totaling 540 data items. The two largest categories of data were "past history of clinical finding", and "physical examination procedure" with 251 and 75 data items respectively. Our study showed a high diversity of data items in the preoperative assessment. Because of the diversity of patients and treatment options available one undisputed preoperative assessment data set is hard to define. However, to solve the problem of exchangeability of the information at least anesthesiologists should use a same core set of data. PMID:18487719

  3. Preoperative patient assessment: a review of the literature and recommendations.

    PubMed Central

    Barnard, N. A.; Williams, R. W.; Spencer, E. M.

    1994-01-01

    The aims of preoperative assessment of patients are outlined, and the role of clinical and laboratory testing is defined. Following a review of the literature, guidelines for requesting such investigations are suggested. PMID:7979066

  4. Preoperative assessment and optimization in periampullary and pancreatic cancer.

    PubMed

    Myatra, S; Divatia, J V; Jibhkate, B; Barreto, G S; Shrikhande, S V

    2011-01-01

    Perioperative management of pancreatic and periampullary cancer poses a considerable challenge to the pancreatic surgeon, anesthesiologist, and the intensive care team. The preoperative surgical evaluation of a pancreatic lesion aims to define the nature of the lesion (malignant or benign), stage the tumor, and to determine resectability or other non-surgical treatment options. Patients are often elderly and may have significant comorbidities and malnutrition. Obstructive jaundice may lead to coagulopathy, infection, renal dysfunction, and adverse outcomes. Routine preoperative biliary drainage can result in higher complication rates, and metal stents may be preferred over plastic stents in selected patients with resectable disease. Judicious use of antibiotics and maintaining fluid volume preoperatively can reduce the incidence of infection and renal dysfunction, respectively. Perioperative fluid therapy with hemodynamic optimization using minimally invasive monitoring may help improve outcomes. Careful patient selection, appropriate preoperative evaluation and optimization can greatly contribute to a favorable outcome after major pancreatic resections. PMID:21248439

  5. Appraisal of guidelines for pre-operative body wash.

    PubMed

    Edström, Elisabet; Westerberg, Lisa; Henricson, Maria

    The pre-operative body wash is a strategy for reducing post-operative infection. However, there is a lack of knowledge about its importance. The purpose of the present study was to evaluate the quality of guidelines for the pre-operative body wash using the AGREE instrument--35 guidelines containing instructions for the pre-operative body wash or preparation were included. The AGREE instrument was employed to establish a quality assessment framework that facilitated a comparison of the guidelines. The results were based on the six domains of the AGREE instrument, all of which were found to have low adherence. Descriptive statistics were used to present the assessment score. The AGREE instrument is useful for evaluating the quality of clinical guidelines. The development of evidence-based guidelines must include clinical activities. Further research is required to clarify the pre-operative body wash process and how it should be performed to reduce post-operative infection. PMID:25426523

  6. Improving pre-operative medicines reconciliation

    PubMed Central

    Brunswicker, Annemarie; Yogarajah, Amieth

    2014-01-01

    An audit of 143 surgical admissions showed that only 30% of general surgery and urology patients have complete medication charts on the day of surgery prior to going to theatre, compared to 94% of orthopaedic patients. This was despite having been seen previously in the pre-operative assessment clinic (POAC). These patients went to the wards post-operatively, where many then missed doses of their life-sustaining medications. Orthopaedic patients see a prescribing pharmacist in POAC who undertakes medicines reconciliation; this is performed by junior doctors for surgical patients. We designed three interventions to improve drug chart completion by junior doctors, and gathered prospective data for 22 weeks in the POAC. We also recorded attendance of junior doctors in the POAC and reasons for absence. Daily and weekly percentages of drug chart completion were plotted on a run chart. The baseline completion rate was 43%. This rose to 45% after the first and second interventions, and 51% after the third intervention. However, the completion rate remained markedly below our target of 94%. Junior doctors attended only 44% of POACs. They reported being “too busy to attend” 41% of the time, and could not be contacted on 11% of occasions. Junior doctors reported that they were unable to attend to both unwell inpatients and the POAC, the latter seeming less of a priority. This was despite a rota allocating doctors to attend POAC sessions free from clinical or teaching commitments. We were unable to increase the rate of drug chart completion with the resources available. We therefore recommend the employment of prescribing pharmacists in the POAC for general surgery and urology patients.

  7. How to accurately bypass damage

    PubMed Central

    Broyde, Suse; Patel, Dinshaw J.

    2016-01-01

    Ultraviolet radiation can cause cancer through DNA damage — specifically, by linking adjacent thymine bases. Crystal structures show how the enzyme DNA polymerase η accurately bypasses such lesions, offering protection. PMID:20577203

  8. Mastectomy following preoperative chemotherapy. Strict operative criteria control operative morbidity.

    PubMed

    Broadwater, J R; Edwards, M J; Kuglen, C; Hortobagyi, G N; Ames, F C; Balch, C M

    1991-02-01

    The surgical morbidity associated with aggressive preoperative chemotherapy in 106 patients with advanced primary breast cancer who had chemotherapy followed by mastectomy was examined. These patients were compared with a group of 91 consecutive patients who had mastectomy without preoperative chemotherapy. Strict operative criteria were used to determine the timing of mastectomy following chemotherapy. Wound infection rates were no different in the preoperative chemotherapy group compared to the mastectomy-alone groups (7% versus 4%; p = 0.62). The incidence of wound necrosis was similar (11% versus 6%; p = 0.29). Seroma formation was decreased significantly in the preoperative chemotherapy group compared to the mastectomy-alone group (15% versus 28%; p = 0.04). Intensive preoperative chemotherapy did not delay the reinstitution of postoperative treatment (30% versus 20%; p = 0.27). However, when delay in instituting postoperative chemotherapy was more than 30 days, there was a significant decrease in overall survival rate (p = 0.04). This study provides evidence that intensive preoperative chemotherapy and mastectomy can be performed without increased morbidity. Furthermore it is important to institute systemic chemotherapy within 30 days of mastectomy to achieve maximum survival. PMID:1992938

  9. Accurate Evaluation of Quantum Integrals

    NASA Technical Reports Server (NTRS)

    Galant, David C.; Goorvitch, D.

    1994-01-01

    Combining an appropriate finite difference method with Richardson's extrapolation results in a simple, highly accurate numerical method for solving a Schr\\"{o}dinger's equation. Important results are that error estimates are provided, and that one can extrapolate expectation values rather than the wavefunctions to obtain highly accurate expectation values. We discuss the eigenvalues, the error growth in repeated Richardson's extrapolation, and show that the expectation values calculated on a crude mesh can be extrapolated to obtain expectation values of high accuracy.

  10. The value of routine preoperative chest roentgenograms in infants and children

    SciTech Connect

    Farnsworth, P.B.; Steiner, E.; Klein, R.M.; SanFilippo, J.A.

    1980-08-01

    The charts and routine preoperative roentgenograms of 350 children admitted for elective pediatric surgery were analyzed to evaluate the clinical importance of routine preoperative chest roentgenograms. This analysis, and a review of the literature, should indicate that routine preoperative roentgenograms for elective pediatric surgery are unnecessary. Indications for selected preoperative roentgenograms based on patients' history and clinical findings are enumerated.

  11. Negative predictive value of preoperative computed tomography in determining pathologic local invasion, nodal disease, and abdominal metastases in gastric cancer

    PubMed Central

    Kagedan, D.J.; Frankul, F.; El-Sedfy, A.; McGregor, C.; Elmi, M.; Zagorski, B.; Dixon, M.E.; Mahar, A.L.; Vasilevska-Ristovska, J.; Helyer, L.; Rowsell, C.; Swallow, C.J.; Law, C.H.; Coburn, N.G.

    2016-01-01

    Background Before undergoing curative-intent resection of gastric adenocarcinoma (ga), most patients undergo abdominal computed tomography (ct) imaging to determine contraindications to resection (local invasion, distant metastases). However, the ability to detect contraindications is variable, and the literature is limited to single-institution studies. We sought to assess, on a population level, the clinical relevance of preoperative ct in evaluating the resectability of ga tumours in patients undergoing surgery. Methods In a provincial cancer registry, 2414 patients with ga diagnosed during 2005–2008 at 116 institutions were identified, and a primary chart review of radiology, operative, and pathology reports was performed for all patients. Preoperative abdominal ct reports were compared with intraoperative findings and final pathology reports (reference standard) to determine the negative predictive value (npv) of ct in assessing local invasion, nodal involvement, and intra-abdominal metastases. Results Among patients undergoing gastrectomy, the npv of ct imaging in detecting local invasion was 86.9% (n = 536). For nodal metastasis, the npv of ct was 43.3% (n = 450). Among patients undergoing surgical exploration, the npv of ct for intra-abdominal metastases was 52.3% (n = 407). Conclusions Preoperative abdominal ct imaging reported as negative is most accurate in determining local invasion and least accurate in nodal assessment. The poor npv of ct should be taken into account when selecting patients for staging laparoscopy. PMID:27536178

  12. Preoperative indicators of clinical outcome following stereotaxic pallidotomy.

    PubMed

    Kazumata, K; Antonini, A; Dhawan, V; Moeller, J R; Alterman, R L; Kelly, P; Sterio, D; Fazzini, E; Beric, A; Eidelberg, D

    1997-10-01

    We assessed the utility of preoperative clinical assessment and functional brain imaging with 18F-fluorodeoxyglucose (FDG) and positron emission tomography (PET) in predicting the clinical outcome of stereotaxic pallidotomy for the treatment of advanced Parkinson's disease (PD). Twenty-two PD patients undergoing posteroventral pallidotomy were assessed preoperatively with the Core Assessment Program for Intracerebral Transplantation (CAPIT) ratings measured on and off levodopa; quantitative FDG/PET was also performed before surgery. Preoperative clinical and metabolic measurements were correlated with changes in off-state CAPIT ratings determined 3 months after surgery. Clinical outcome following pallidotomy was also correlated with intraoperative measures of spontaneous pallidal single-unit activity as well as postoperative MRI measurements of lesion volume and location. We found that unilateral pallidotomy resulted in variable clinical improvement in off-state CAPIT scores for the contralateral limbs (mean change 30.9 +/- 15.5%). Postoperative MRI revealed that pallidotomy lesions were comparable in location and volume across the patients. Clinical outcome following surgery correlated significantly with preoperative measures of CAPIT score change with levodopa administration (r = 0.60, p < 0.005) and with preoperative FDG/PET measurements of lentiform glucose metabolism (r = 0.71, p < 0.0005). Operative outcome did not correlate with intraoperative measures of spontaneous pallidal neuronal firing rate. We conclude that preoperative measurements of lentiform glucose metabolism and levodopa responsiveness may be useful indicators of motor improvement following pallidotomy. Both preoperative quantitative measures, either singly or in combination, may be helpful in selecting optimal candidates for surgery. PMID:9339694

  13. Preoperative Body Mass Index, Blood Albumin and Triglycerides Predict Survival for Patients with Gastric Cancer

    PubMed Central

    Liu, Bin Zheng; Tao, Lin; Chen, Yun Zhao; Li, Xu Zhe; Dong, Yu Ling; Ma, Ya Jing; Li, Shu Gang; Li, Feng; Zhang, Wen Jie

    2016-01-01

    GC patients superior to postoperative TNM system in terms of timing for management. As potential survival-predictors, preoperative tests of BMI, albumin and triglyceride, combined with clinical imaging, may help personalized management for GC patients including planning surgical strategy, optimal radio-chemotherapy and appropriate follow-up intervals after surgery. PMID:27309531

  14. Superconducting Super Collider site environmental report for calendar year 1991. Pre-operational

    SciTech Connect

    1995-05-01

    This is the first annual SER prepared for the SSC project. It is a pre-operational report, intended primarily to describe the baseline characterization of the Ellis County, Texas site that has been developed subsequent to the Environmental Impact Statement (EIS) and the Supplemental Environmental impact Statement (SEIS). As such, the emphasis will be on environmental compliance efforts, including monitoring and mitigation programs. The SER also reports on the measures taken to meet the commitments made in the EIS and SEIS. These measures are detailed in the Mitigation Action Plan (MAP) (Department of Energy (DOE), 1991), which was prepared following the signing of the Record of Decision (ROD) to construct the SSC in Texas. The SER will continue to be preoperational until the first high-energy (20 trillion electron volt or TeV) protons collisions are observed, at which point the SSC will become operational. At that time, the SER will place more emphasis on the radiological monitoring program. This SER will report on actions taken in 1991 or earlier and briefly mention some of those planned for calendar year 1992. AU actions completed in 1992 will be addressed in the SER for calendar year 1992.

  15. Effect of Preoperative Pain on Inferior Alveolar Nerve Block

    PubMed Central

    Aggarwal, Vivek; Singla, Mamta; Subbiya, Arunajatesan; Vivekanandhan, Paramasivam; Sharma, Vikram; Sharma, Ritu; Prakash, Venkatachalam; Geethapriya, Nagarajan

    2015-01-01

    The present study tested the hypothesis that the amount and severity of preoperative pain will affect the anesthetic efficacy of inferior alveolar nerve block (IANB) in patients with symptomatic irreversible pulpitis. One-hundred seventy-seven adult volunteer subjects, actively experiencing pain in a mandibular molar, participated in this prospective double-blind study carried out at 2 different centers. The patients were classified into 3 groups on the basis of severity of preoperative pain: mild, 1–54 mm on the Heft-Parker visual analog scale (HP VAS); moderate, 55–114 mm; and severe, greater than 114 mm. After IANB with 1.8 mL of 2% lidocaine, endodontic access preparation was initiated. Pain during treatment was recorded using the HP VAS. The primary outcome measure was the ability to undertake pulp access and canal instrumentation with no or mild pain. The success rates were statistically analyzed by multiple logistic regression test. There was a significant difference between the mild and severe preoperative pain group (P = .03). There was a positive correlation between the values of preoperative and intraoperative pain (r = .2 and .4 at 2 centers). The amount of preoperative pain can affect the anesthetic success rates of IANB in patients with symptomatic irreversible pulpitis. PMID:26650491

  16. Role of preoperative embolization for intradural spinal hemangioblastomas.

    PubMed

    Ampie, Leonel; Choy, Winward; Khanna, Ryan; Smith, Zachary A; Dahdaleh, Nader S; Parsa, Andrew T; Bloch, Orin

    2016-02-01

    Spinal hemangioblastomas (HB) are relatively rare neoplasms with a high degree of vascularity. Therapy for symptomatic tumors involves total resection when possible. Due to the enriched blood supply of these neoplasms, there is a high risk of significant intraoperative blood loss, which can lead to perioperative complications. Preoperative embolization of HB has been suggested to reduce blood loss and operative morbidity, but its use remains controversial. Data on the risks and benefits of preoperative embolization for this tumor remains limited. We identified and analyzed all 29 reported cases of preoperative embolization of intradural spinal HB within the literature. There were 18 men and nine women, and patients ranged from 24 to 61 years of age. Mean tumor size was 3.5 cm. Cervical and thoracic location was most common, accounting for 48.3% and 20% of cases, respectively. Complications from embolization and surgery were minimal, with no deaths or permanent neurological morbidity. Minimal intraoperative bleeding and excellent rates of gross total resection were reported with preoperative embolization. However, outcomes from microsurgery alone from historical series have similarly reported excellent outcomes. While there is no established standard, preoperative embolization should be reserved for particularly high risk patients with risk of intraoperative bleeding. PMID:26585384

  17. Effect of Preoperative Pain on Inferior Alveolar Nerve Block.

    PubMed

    Aggarwal, Vivek; Singla, Mamta; Subbiya, Arunajatesan; Vivekanandhan, Paramasivam; Sharma, Vikram; Sharma, Ritu; Prakash, Venkatachalam; Geethapriya, Nagarajan

    2015-01-01

    The present study tested the hypothesis that the amount and severity of preoperative pain will affect the anesthetic efficacy of inferior alveolar nerve block (IANB) in patients with symptomatic irreversible pulpitis. One-hundred seventy-seven adult volunteer subjects, actively experiencing pain in a mandibular molar, participated in this prospective double-blind study carried out at 2 different centers. The patients were classified into 3 groups on the basis of severity of preoperative pain: mild, 1-54 mm on the Heft-Parker visual analog scale (HP VAS); moderate, 55-114 mm; and severe, greater than 114 mm. After IANB with 1.8 mL of 2% lidocaine, endodontic access preparation was initiated. Pain during treatment was recorded using the HP VAS. The primary outcome measure was the ability to undertake pulp access and canal instrumentation with no or mild pain. The success rates were statistically analyzed by multiple logistic regression test. There was a significant difference between the mild and severe preoperative pain group (P = .03). There was a positive correlation between the values of preoperative and intraoperative pain (r = .2 and .4 at 2 centers). The amount of preoperative pain can affect the anesthetic success rates of IANB in patients with symptomatic irreversible pulpitis. PMID:26650491

  18. Preoperative myocardial ischaemia: its relation to perioperative infarction.

    PubMed Central

    Yousif, H; Davies, G; Westaby, S; Prendiville, O F; Sapsford, R N; Oakley, C M

    1987-01-01

    One hundred consecutive patients undergoing coronary artery bypass surgery were randomly allocated to a preoperative (24 h) intravenous infusion of isosorbide dinitrate (1.5-15 mg/hr) (50 patients) or to placebo (50 patients). The characteristics of the two groups were similar. Evidence of acute myocardial ischaemia was sought by continuous electrocardiographic Holter recordings and acute myocardial infarction by the appearance of new Q waves and increased activity of the creatine kinase MB isoenzyme. Episodes of acute myocardial ischaemia were found in 18% of patients in the control group and in none of those who received isosorbide dinitrate. None the less, the frequency of perioperative myocardial infarction was similar (22% and 18% respectively) in the two groups. Perioperative infarction was significantly more common in women, in patients with unstable angina or poor left ventricular function, in those who had coronary endarterectomy, and in those in whom the aortic clamping time was greater than 50 minutes. These factors may have obscured any effect that prevention of preoperative ischaemia had on perioperative infarction. Preoperative infusion of isosorbide dinitrate eliminated preoperative ischaemia but did not influence the occurrence of perioperative infarction. The probable benefits of prevention of preoperative ischaemia on postoperative left ventricular function, which is a determinant of long term survival, remain to be established. PMID:3304371

  19. Prognostic Value of Preoperatively Obtained Clinical and Laboratory Data in Predicting Survival Following Orthotopic Liver Transplantation

    PubMed Central

    Cuervas-Mons, Valentin; Millan, Isabel; Gavaler, Judith S.; Starzl, Thomas E.; Van Thiel, David H.

    2010-01-01

    Twenty-seven clinical and laboratory data and the subsequent clinical course of 93 consecutive adult patients who underwent orthotopic liver transplantation for various chronic advanced liver diseases were analyzed retrospectively to assess the risk factors of early major bacterial infection and death after the procedure. Forty-one patients (44%) had early major bacterial infection during hospitalization for orthotopic liver transplantation. The mortality rate was 70.7% in patients with early major bacterial infection and was 7.7% in patients without early major bacterial infection (p < 0.001). Total serum bilirubin, total white blood cell count and polymorphonuclear cell count, IgG (all p < 0.05) and plasma creatinine level (p < 0.001) were higher in patients that developed early major bacterial infection than in those who did not. By step-wise discriminant analysis, the strongest risk factor for early major bacterial infection was the serum creatinine level, which achieved an accuracy of 69% for a creatinine level greater than 1.58 mg per dl. Seven variables (ascites, hepatic encephalopathy, elevated white blood and polymorphonuclear cell count, decreased helper to suppressor T cell ratio and elevated plasma creatinine and bilirubin levels) were associated with a significant increased risk for death. A step-wise discriminant analysis of these seven factors resulted in the demonstration of serum creatinine as the greatest risk factor for mortality. A preoperative serum creatinine either less than or greater than 1.72 mg per dl accurately predicts survival or death, respectively, in 79% of cases. These data suggest that the baseline preoperative serum creatinine level provides the best indication of the short-term prognosis after liver transplantation than does any other preoperatively obtained index of the patient’s status. PMID:3530947

  20. A probability score for preoperative prediction of type 2 diabetes remission following RYGB surgery

    PubMed Central

    Still, Christopher D.; Wood, G. Craig; Benotti, Peter; Petrick, Anthony T.; Gabrielsen, Jon; Strodel, William E.; Ibele, Anna; Seiler, Jamie; Irving, Brian A.; Celaya, Melisa P.; Blackstone, Robin; Gerhard, Glenn S.; Argyropoulos, George

    2014-01-01

    BACKGROUND Type 2 diabetes (T2D) is a metabolic disease with significant medical complications. Roux-en-Y gastric bypass (RYGB) surgery is one of the few interventions that remit T2D in ~60% of patients. However, there is no accurate method for predicting preoperatively the probability for T2D remission. METHODS A retrospective cohort of 2,300 RYGB patients at Geisinger Clinic was used to identify 690 patients with T2D and complete electronic data. Two additional T2D cohorts (N=276, and N=113) were used for replication at 14 months following RYGB. Kaplan-Meier analysis was used in the primary cohort to create survival curves until remission. A Cox proportional hazards model was used to estimate the hazard ratios on T2D remission. FINDINGS Using 259 preoperative clinical variables, four (use of insulin, age, HbA1c, and type of antidiabetic medication) were sufficient to develop an algorithm that produces a type 2 diabetes remission (DiaRem) score over five years. The DiaRem score spans from 0 to 22 and was divided into five groups corresponding to five probability-ranges for T2D remission: 0–2 (88%–99%), 3–7 (64%–88%), 8–12 (23%–49%), 13–17 (11%–33%), 18–22 (2%–16%). The DiaRem scores in the replication cohorts, as well as under various definitions of diabetes remission, conformed to the DiaRem score of the primary cohort. INTERPRETATION The DiaRem score is a novel preoperative method for predicting the probability (from 2% to 99%) for T2D remission following RYGB surgery. FUNDING This research was supported by the Geisinger Health System and the National Institutes of Health. PMID:24579062

  1. Patterns of Response After Preoperative Intensity-Modulated Radiation Therapy and Capecitabine/Oxaliplatin in Rectal Cancer: Is There Still a Place for Ecoendoscopic Ultrasound?

    SciTech Connect

    Arbea, Leire; Diaz-Gonzalez, Juan A.; Subtil, Jose Carlos; Sola, Josu; Hernandez-Lizoain, Jose Luis; Martinez-Monge, Rafael; Moreno, Marta; Aristu, Javier

    2011-10-01

    Purpose: The main goals of preoperative chemoradiotherapy (CHRT) in rectal cancer are to achieve pathological response and to ensure tumor control with functional surgery when possible. Assessment of the concordance between clinical and pathological responses is necessary to make decisions regarding alternative conservative procedures. The present study evaluates the patterns of response after a preoperative CHRT regimen, and the value of endoscopic ultrasound (EUS) in assessing response. Methods and Materials: A total of 51 EUS-staged T3 to T4 and/or N0 to N+ rectal cancer patients received preoperative CHRT (intensity-modulated radiation therapy and capecitabine/oxaliplatin (XELOX) followed by radical resection. Clinical response was assesed by EUS. Rates of pathological tumor regression grade (TRG) and lymph node (LN) involvement were determined in the surgical specimen. Clinical and pathological responses were compared, and the accuracy of EUS in assessing response was calculated. Results: Twenty-four patients (45%) achieved a major pathological response (complete or >95% pathological response (TRG 3+/4)). Sensitivity, specificity, negative predictive value, and positive predictive value of EUS in predicting pathological T response after preoperative CHRT were 77.8%, 37.5%, 60%, and 58%, respectively. The EUS sensitivity, specificity, negative predictive value, and positive predictive value for nodal staging were 44%, 88%, 88%, and 44%, respectively. Furthermore, EUS after CHRT accurately predicted the absence of LN involvement in 7 of 7 patients (100%) with major pathological response of the primary tumor. Conclusion: Preoperative IMRT with concomitant XELOX induces favorable rates of major pathological response. EUS has a limited ability to predict primary tumor response after preoperative CHRT, but it is useful for accurately determining LN status. EUS may have a potential value in identifying patients with a very low risk of LN involvement in association

  2. Nonpalpable thyroid carcinoma: clinical controversies on preoperative selection.

    PubMed

    Carpi, Angelo; Nicolini, Andrea; Casara, Dario; Rubello, Domenico; Rosa Pelizzo, Maria

    2003-06-01

    This article emphasizes some controversies concerning the preoperative selection of nonpalpable thyroid tumors. The prevalence of occult thyroid carcinoma in surgical series (1.8-10%) is not higher than in autopsy thyroid series (2.7-24%). The prevalence of occult thyroid carcinoma in thyroid glands examined in the same institution by ultrasound, for a clinical thyroid abnormality or for investigation of other neck structures without clinically evident or suspected thyroid disease, varies from 3% to 8% and is very similar independent of the fact that a thyroid abnormality is or is not the indication for ultrasonography. These data suggest that the presence of a thyroid disease is not a risk factor for harboring an occult thyroid carcinoma (except for C-cell hyperplasia in the rare case of MEN 2 syndromes). As it is not cost effective to examine all the nonpalpable lesions with fine-needle aspiration (FNA) guided by ultrasounds, it is necessary to define to which extent ultrasound is useful in selecting those lesions to be examined cytologically by FNA. The use of ultrasound to select these lesions is very controversial. Ultrasound-guided cytologic diagnosis of nonpalpable nodules is not as accurate as in the case of palpable nodules. Sampling of material adequate for cytologic analysis depends on the lesion size; it is 64% for a 0.7-cm lesion and it increases to 86.7% for a mean size of 1.1 cm. For the diagnosis of occult thyroid carcinomas (< or =1 cm), sensitivity is 35.8% and false-negative results are 49.3%. Nonpalpable nodules with a size of 1.5 cm represent an absolute indication to perform an ultrasound-guided FNA because this is the size limit for dividing thyroid nodules in probably innocuous or potentially dangerous categories and because the cytologic diagnosis of nodules of this size is sufficiently reliable. For the smaller incidentally discovered thyroid nodules following ultrasound, physicians should discuss with the patient whether and when to

  3. Improved Surgical Site Infection (SSI) rate through accurately assessed surgical wounds

    PubMed Central

    John, Honeymol; Nimeri, Abdelrahman; ELLAHHAM, SAMER

    2015-01-01

    Sheikh Khalifa Medical City's (SKMC) Surgery Institute was identified as a high outlier in Surgical Site Infections (SSI) based on the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) - Semi-Annual Report (SAR) in January 2012. The aim of this project was to improve SSI rates through accurate wound classification. We identified SSI rate reduction as a performance improvement and safety priority at SKMC, a tertiary referral center. We used the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) best practice guidelines as a guide. ACS NSQIP is a clinical registry that provides risk-adjusted clinical outcome reports every six months. The rates of SSI are reported in an observed/expected ratio. The expected ratio is calculated based on the risk factors of the patients which include wound classification. We established a multidisciplinary SSI taskforce. The members of the SSI taskforce included the ACS NSQIP team members, quality, surgeons, nurses, infection control, IT, pharmacy, microbiology, and it was chaired by a colorectal surgeon. The taskforce focused on five areas: pre-op showering and hair removal, skin antisepsis, prophylactic antibiotics, peri-operative maintenance of glycaemia, and normothermia. We planned audits to evaluate our wound classification and our SSI rates based on the SAR. Our expected SSI rates in general surgery and the whole department were 2.52% and 1.70% respectively, while our observed SSI rates were 4.68% and 3.57% respectively, giving us a high outlier status with an odd's ratio of 1.72 and 2.03. Wound classifications were identified as an area of concern. For example, wound classifications were preoperatively selected based on the default wound classification of the booked procedure in the Electronic Medical Record (EMR) which led to under classifying wounds in many occasions. A total of 998 cases were reviewed, our rate of incorrect wound classification

  4. Preoperative surgical marking: a case of seeing double.

    PubMed

    Rughani, Milap; Kokkinakis, Michail; Davison, Marc

    2010-01-01

    Preoperative marking is an integral part of the care of patients undergoing surgical procedures. It occurs on a daily basis in hospitals and involves all members of the healthcare staff and the patient. Incorrect marking or errors can lead to devastating consequences for the patient and staff involved. We present an unusual case of seeing double arrows on a patient undergoing emergency orthopaedic surgery, despite standard preoperative marking procedures. This was recognised in the anaesthetic room and the correct site was confirmed. We aim to highlight this specific problem and remind all involved in preoperative marking of the dangers of a mirror imprint, thereby avoiding seeing double in the anaesthetic or operating room. PMID:22315636

  5. [Research hotspot and progress of preoperative chemoradiotherapy for rectal cancer].

    PubMed

    Peng, Jianhong; Pan, Zhizhong

    2016-06-01

    Preoperative chemoradiotherapy (CRT) has become an important component of comprehensive treatment for rectal cancer. Although local recurrent risk has been remarkably reduced by CRT, distant metastasis remains the main cause of therapeutic failure. Therefore, more and more studies focused on controlling distant metastasis in order to prolong long-term survival. Recently, CRT has achieved certain progression in rectal cancer: (1)Patients with stage T3 should be classified into specific subgroups to formulate individualized treatment regimen. For stage T3a, it is feasible to perform surgery alone or administrate low intensity preoperative CRT; for stage T3b and T3c, conventional preoperative CRT should be performed in order to reduce the risk of recurrence postoperatively. (2)With regard to combined regimen for chemotherapy, oral capecitabine superiors to intravenous bolus 5-fluorouracil (5-FU) and is comparable to continuous intravenous infusion 5-FU with a better safety. Therefore, capecitabine is recommended for older patients and those with poor tolerance to chemotherapy. Compared to single 5-FU concurrent CRT, addition of oxaliplatin into preoperative CRT may result in a higher survival benefit in Chinese patients. As to the application of irinotecan, bevacizumab or cetuximab, unless there are more evidence to confirm their efficacy and safety from randomized controlled trial, they should not be recommended for adding to preoperative CRT routinely. (3)On the optimization in CRT pattern, the application values of induction chemotherapy before concurrent CRT, consolidation chemotherapy after concurrent CRT, neoadjuvant sandwich CRT, neoadjuvant chemotherapy alone and short-course preoperative radiotherapy remain further exploration. (4)On the treatment strategy for clinical complete response (cCR) after CRT, whether "wait and see" strategy is able to be adopted, it is still a hot topic with controversy. PMID:27353093

  6. Impact of preoperative antithrombotic therapy on blood management after implantation of primary total knee arthroplasty.

    PubMed

    Leitner, Lukas; Musser, Ewald; Kastner, Norbert; Friesenbichler, Jörg; Hirzberger, Daniela; Radl, Roman; Leithner, Andreas; Sadoghi, Patrick

    2016-01-01

    Red blood cell concentrates (RCC) substitution after total knee arthroplasty (TKA) is correlated with multifold of complications and an independent predictor for higher postoperative mortality. TKA is mainly performed in elderly patients with pre-existing polymorbidity, often requiring permanent preoperative antithrombotic therapy (PAT). The aim of this retrospective analysis was to investigate the impact of demand for PAT on inpatient blood management in patients undergoing TKA. In this study 200 patients were retrospectively evaluated after TKA for differences between PAT and non-PAT regarding demographic parameters, preoperative ASA score > 2, duration of operation, pre-, and intraoperative hemoglobin level, and postoperative parameters including amount of wound drainage, RCC requirement, and inpatient time. In a multivariate logistic regression analysis the independent influences of PAT, demographic parameters, ASA score > 2, and duration of the operation on RCC demand following TKA were analyzed. Patients with PAT were significantly older, more often had an ASA > 2 at surgery, needed a higher number of RCCs units and more frequently and had lower perioperative hemoglobin levels. Multivariate logistic regression revealed PAT was an independent predictor for RCC requirement. PAT patients are more likely to require RCC following TKA and should be accurately monitored with respect to postoperative blood loss. PMID:27488941

  7. Impact of preoperative antithrombotic therapy on blood management after implantation of primary total knee arthroplasty

    PubMed Central

    Leitner, Lukas; Musser, Ewald; Kastner, Norbert; Friesenbichler, Jörg; Hirzberger, Daniela; Radl, Roman; Leithner, Andreas; Sadoghi, Patrick

    2016-01-01

    Red blood cell concentrates (RCC) substitution after total knee arthroplasty (TKA) is correlated with multifold of complications and an independent predictor for higher postoperative mortality. TKA is mainly performed in elderly patients with pre-existing polymorbidity, often requiring permanent preoperative antithrombotic therapy (PAT). The aim of this retrospective analysis was to investigate the impact of demand for PAT on inpatient blood management in patients undergoing TKA. In this study 200 patients were retrospectively evaluated after TKA for differences between PAT and non-PAT regarding demographic parameters, preoperative ASA score > 2, duration of operation, pre-, and intraoperative hemoglobin level, and postoperative parameters including amount of wound drainage, RCC requirement, and inpatient time. In a multivariate logistic regression analysis the independent influences of PAT, demographic parameters, ASA score > 2, and duration of the operation on RCC demand following TKA were analyzed. Patients with PAT were significantly older, more often had an ASA > 2 at surgery, needed a higher number of RCCs units and more frequently and had lower perioperative hemoglobin levels. Multivariate logistic regression revealed PAT was an independent predictor for RCC requirement. PAT patients are more likely to require RCC following TKA and should be accurately monitored with respect to postoperative blood loss. PMID:27488941

  8. Preoperative localization of parathyroid lesion: diagnostic usefulness of color doppler ultrasonography

    PubMed Central

    mohammadi, Afshin; Moloudi, Farzad; Ghasemi-rad, Mohammad

    2012-01-01

    Introduction Recently, minimally invasive parathyroidectomy (MIP) has been developed and is gaining popularity among surgeons. For this reason, preoperative localization is playing an important role to detect the precise location of the affected gland and to increase the success rate. Material and methods From June 2007 to June 2011, 56 consecutive patients (11 men and 45 women) with primary or secondary hyperparathyroidism in our center underwent Gray scale, color Doppler and 99m-Tc MIBI scan prior to operative management of parathyroid lesions. Results The sensitivity, specificity and accuracy of US and MIBI scan for pHPT was 88%, 94%, 91% and 70%, 100% and 85% respectively. In patients with sHPT, the sensitivity, specificity and accuracy of US and MIBI scan was 54%, 93%, 76% and 25%, 100% and 72.9% respectively. The overall sensitivity of combined US and MIBI scan in pHPT and sHPT was 97% and 45% respectively. The overall sensitivity, specificity and accuracy of CDUS in diagnosis of parathyroid lesions in pHPT and sHPT is 97%, 100%, 98.6% and 62%, 100% and 83% respectively. Conclusion The overall sensitivity and specificity of US and MIBI in preoperative localization of parathyroid adenoma in sHPT is lower than pHPT and performing CDUS can increases the overall sensitivity and specificity of imaging methods in accurate localization of parathyroid lesion. PMID:22328952

  9. Effect of preoperative irradiation on healing of low colorectal anastomoses

    SciTech Connect

    Morgenstern, L.; Sanders, G.; Wahlstrom, E.; Yadegar, J.; Amodeo, P.

    1984-02-01

    The effect of preoperative irradiation on the healing of low colorectal anastomoses was studied experimentally. In 12 dogs in whom preoperative irradiation of 4,000 rads was given before low colorectal stapled anastomosis was performed, anastomotic leakage occurred in 66 percent. More than half of the anastomotic leaks were associated with either severe sepsis or death. In a matched group of control animals that underwent stapled anastomoses without irradiation, no anastomotic complications occurred. The clinical implications of this study are that stapled anastomoses in irradiated colon are at serious risk of anastomotic dehiscence and, therefore, should be protected with a proximal colostomy.

  10. [Importance of preoperative and intraoperative imaging for operative strategies].

    PubMed

    Nitschke, P; Bork, U; Plodeck, V; Podlesek, D; Sobottka, S B; Schackert, G; Weitz, J; Kirsch, M

    2016-03-01

    Recent advances in preoperative and postoperative imaging have an increasing influence on surgical decision-making and make more complex surgical interventions possible. This improves the possibilities for frequently occurring challenges and promoting improved functional and oncological outcome. This manuscript reviews the role of preoperative and intraoperative imaging in surgery. Various techniques are explained based on examples from hepatobiliary surgery and neurosurgery, in particular real-time procedures, such as the online use of augmented reality and in vivo fluorescence, as well as new and promising optical techniques including imaging of intrinsic signals and vibrational spectroscopy. PMID:26939896

  11. Prognostic significance of preoperative fibrinogen in patients with colon cancer

    PubMed Central

    Sun, Zhen-Qiang; Han, Xiao-Na; Wang, Hai-Jiang; Tang, Yong; Zhao, Ze-Liang; Qu, Yan-Li; Xu, Rui-Wei; Liu, Yan-Yan; Yu, Xian-Bo

    2014-01-01

    AIM: To investigate the prognostic significance of preoperative fibrinogen levels in colon cancer patients. METHODS: A total of 255 colon cancer patients treated at the Affiliated Tumor Hospital of Xinjiang Medical University from June 1st 2005 to June 1st 2008 were enrolled in the study. All patients received radical surgery as their primary treatment method. Preoperative fibrinogen was detected by the Clauss method, and all patients were followed up after surgery. Preoperative fibrinogen measurements were correlated with a number of clinicopathological parameters using the Student t test and analysis of variance. Survival analyses were performed by the Kaplan-Meier method and Cox regression modeling to measure 5-year disease-free survival (DFS) and overall survival (OS). RESULTS: The mean preoperative fibrinogen concentration of all colon cancer patients was 3.17 ± 0.88 g/L. Statistically significant differences were found between preoperative fibrinogen levels and the clinicopathological parameters of age, smoking status, tumor size, tumor location, tumor-node-metastasis (TNM) stage, modified Glasgow prognostic scores (mGPS), white blood cell (WBC) count, neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and carcinoembryonic antigen (CEA) levels. Univariate survival analysis showed that TNM stage, tumor cell differentiation grade, vascular invasion, mGPS score, preoperative fibrinogen, WBC, NLR, PLR and CEA all correlated with both OS and DFS. Alpha-fetoprotein (AFP) and body mass index correlated only with OS. Kaplan-Meier analysis revealed that both OS and DFS of the total cohort, as well as of the stage II and III patients, were higher in the hypofibrinogen group compared to the hyperfibrinogen group (all P < 0.05). In contrast, there was no significant difference between OS and DFS in stage I patients with low or high fibrinogen levels. Cox regression analysis indicated preoperative fibrinogen levels, TNM stage, mGPS score, CEA, and

  12. Assessing the registration of CT-scan data to intraoperative x rays by fusing x rays and preoperative information

    NASA Astrophysics Data System (ADS)

    Gueziec, Andre P.

    1999-05-01

    This paper addresses a key issue of providing clinicians with visual feedback to validate a computer-generated registration of pre-operative and intra-operative data. With this feedback information, the clinician may decide to proceed with a computer-assisted intervention, revert to a manual intervention, or potentially provide information to the computer system to improve the registration. The paper focuses on total hip replacement (THR) surgery, but similar techniques could be applied to other types of interventions or therapy, including orthopedics, neurosurgery, and radiation therapy. Pre-operative CT data is used to plane the surgery (select an implant type, size and precise position), and is registered to intra-operative X-ray images, allowing to execute the plan: mill a cavity with the implant's shape. (Intra-operative X-ray images must be calibrated with respect to the surgical device executing the plan). One novel technique presented in this paper consists of simulating a post-operative X-ray image of the tissue of interest before doing the procedure, by projecting the registered implant onto an intra-operative X- ray image (corrected for distortion or not), providing clinicians with familiar and easy to interpret images. As an additional benefit, this method provides new means for comparing various strategies for registering pre-operative data to the physical space of the operating room.

  13. Influence of Preoperative Radiation Field on Postoperative Leak Rates in Esophageal Cancer Patients after Trimodality Therapy

    PubMed Central

    Juloori, Aditya; Tucker, Susan L.; Komaki, Ritsuko; Liao, Zhongxing; Correa, Arlene M.; Swisher, Stephen G.; Hofstetter, Wayne L.; Lin, Steven H.

    2014-01-01

    Introduction Postoperative morbidities, such as anastomotic leaks, are common after trimodality therapy (chemoradiation followed by surgery) for esophageal cancer. We investigated for factors associated with an increased incidence of anastomotic leaks. Methods Data from 285 esophageal cancer patients treated from 2000–2011 with trimodality therapy was analyzed. Anastomotic location relative to preoperative radiation field was assessed using postoperative computed tomographic imaging. Logistic regression was used to evaluate for factors associated with any or clinically relevant (CR) (≥ grade 2) leaks. Results Overall anastomotic leak rate was 11% (31/285), and CR leak rate was 6% (17/285). Multivariable analysis identified body mass index (BMI) (OR 1.09, 95%CI 1.00–1.17; OR 1.11, 95%CI 1.01–1.22), three-field surgery (OR 10.01, 95%CI 3.83–26.21; OR 4.83, 95%CI 1.39–16.71), and within radiation field (“in-field”) anastomosis (OR 5.37, 95%CI 2.21–13.04; OR 8.63, 95%CI 2.90–25.65) as independent predictors of both all grade and CR leaks, respectively. While patients with distal esophageal tumors and Ivor-Lewis surgery had the lowest incidence of all grade (6.5%) and CR leaks (4.2%), most of the leaks were associated with the anastomosis constructed within the field of radiation (in-field: 39% and 30% versus out-of-field: 2.6% and 1.0%, respectively, for total and CR leaks, p<0.0001, Fisher’s Exact test). Conclusions Esophagogastric anastomosis placed within the preoperative radiation field was a very strong predictor for anastomotic leaks in esophageal cancer patients treated with trimodality therapy, among other factors. Surgical planning should include a critical evaluation of the preoperative radiation fields to ensure proper anastomotic placement after chemoradiation therapy. PMID:24736077

  14. Mammary analogue secretory carcinoma of parotid: Is preoperative cytological diagnosis possible?

    PubMed

    Oza, Nikita; Sanghvi, Kintan; Shet, Tanuja; Patil, Asawari; Menon, Santosh; Ramadwar, Mukta; Kane, Shubhada

    2016-06-01

    Mammary analogue secretory carcinoma is a recently recognized tumor of salivary gland with characteristic t(12;15)(q13;q25) that results in ETV6-NTRK3 fusion product. Distinguishing mammary analogue secretory carcinoma from other salivary gland tumors is important. Present study highlights cytologic findings in three cases of mammary analogue secretory carcinoma of parotid which facilitate preoperative diagnosis with the aid of ancillary diagnostic techniques. Fine needle aspiration cytology of parotid was performed on three cases after clinical examination. Immunocytochemistry for mammoglobin and S100 were performed. Parotidectomy was done in all cases. The corresponding hematoxylin and eosin stained slides and blocks of all cases were studied. Molecular analysis was done in one of the cases. Cases 1 and 3 revealed uniform atypical epithelial cells arranged in branching papillary pattern with few cells in microcystic pattern. Case 2 showed atypical cells arranged mainly in loose clusters and few singly dissociated. Individual cells revealed round nuclei, vesicular chromatin, prominent nucleoli and abundant finely vacuolated cytoplasm with metachromasia prominent in May-Grunwald-Giemsa smear (case 3). Characteristic hob-nail cells covering papillae were observed in cases 1 and 3. Immunocytochemistry showed strong positivity for mammoglobin and S100 thereby confirming the diagnosis of mammary analogue secretory carcinoma preoperatively. The diagnosis was in concordance with surgical specimen. Also, characteristic ETV6-NTRK3 translocation was confirmed in case 1. Increased awareness and high index of suspicion is necessary for the upfront diagnosis, more so for the papillary variant of mammary analogue secretory carcinoma. Immunocytochemistry aids in confirming this preoperative diagnosis, based on which treatment can be planned. Diagn. Cytopathol. 2016;44:519-525. © 2016 Wiley Periodicals, Inc. PMID:26945684

  15. Recent development of optical coherence tomography for preoperative diagnosis of esophageal malignancies

    PubMed Central

    Uno, Kaname; Koike, Tomoyuki; Shimosegawa, Tooru

    2015-01-01

    Endoscopic diagnosis with histological evidence is necessary to decide the best strategy for treating esophageal squamous cell carcinoma and Barrett’s-associated neoplasia, and the recent development of endoscopic technologies have made possible real-time information of malignant hallmarks. We focused on the development of optical coherence tomography (OCT), the only technology that can depict real-time cross-sectional images with high resolution. With the improvements in image resolution, acquisition rate and demonstrable area of three-dimensional devices with Doppler capability, OCT imaging was shown to enable visualization of structural/functional alterations in the mucosal/submucosal tissue of the esophagus, resulting in more accurate preoperative diagnosis of such malignancies. Moreover, it approved to be useful for targeting malignant areas for biopsy and treatment as well as for predicting the treatment effects. Therefore, further development of this technology is expected to overcome the current clinical issues in management strategies of esophageal malignancies. PMID:26240688

  16. Recent development of optical coherence tomography for preoperative diagnosis of esophageal malignancies.

    PubMed

    Uno, Kaname; Koike, Tomoyuki; Shimosegawa, Tooru

    2015-07-25

    Endoscopic diagnosis with histological evidence is necessary to decide the best strategy for treating esophageal squamous cell carcinoma and Barrett's-associated neoplasia, and the recent development of endoscopic technologies have made possible real-time information of malignant hallmarks. We focused on the development of optical coherence tomography (OCT), the only technology that can depict real-time cross-sectional images with high resolution. With the improvements in image resolution, acquisition rate and demonstrable area of three-dimensional devices with Doppler capability, OCT imaging was shown to enable visualization of structural/functional alterations in the mucosal/submucosal tissue of the esophagus, resulting in more accurate preoperative diagnosis of such malignancies. Moreover, it approved to be useful for targeting malignant areas for biopsy and treatment as well as for predicting the treatment effects. Therefore, further development of this technology is expected to overcome the current clinical issues in management strategies of esophageal malignancies. PMID:26240688

  17. Challenge in preoperative diagnosis of retroperitoneal mucinous cyst in a pediatric patient

    PubMed Central

    Zhang, Deying; Zhang, Yan; Liu, Xing; Zhu, Jin; Feng, Chuan; Yang, Chunjiang; Wu, Shengde; Liu, Junhong; Hua, Yi; Liu, Feng; Zhang, Nan; Zhang, Yuanyuan; He, Dawei; Lin, Tao; Wei, Guanghui

    2015-01-01

    Mucinous cystic lesions of the retroperitoneum can be either neoplastic or non-neoplastic. It is very important to make a correct diagnosis, or at least, an accurate classification, to proceed with an optimal treatment strategy. In spite of advantage of ultrasound and X-ray image examinations, it is still a challenge to make differential diagnosis of retroperitoneal mucinous cyst from gangliocytoma because both tumors have similar density under the image assessment. In this article, we reported an asymptomatic 8-year-old boy with multiple bronchogenic cysts in both lung and adrenal area on the left side, the latter was considered to be a gangliocytoma preoperatively by ultrasound and computed tomography, but confirmed as bronchogenic cyst by histopathology post laparoscopic resection. The differential diagnosis, imaging features and treatment of bronchogenic cyst are discussed and the relative literatures are reviewed. PMID:26770607

  18. Adaptive planning using megavoltage fan-beam CT for radiation therapy with testicular shielding

    SciTech Connect

    Yadav, Poonam; Kozak, Kevin; Tolakanahalli, Ranjini; Ramasubramanian, V.; Paliwal, Bhudatt R.; Welsh, James S.; Rong, Yi

    2012-07-01

    This study highlights the use of adaptive planning to accommodate testicular shielding in helical tomotherapy for malignancies of the proximal thigh. Two cases of young men with large soft tissue sarcomas of the proximal thigh are presented. After multidisciplinary evaluation, preoperative radiation therapy was recommended. Both patients were referred for sperm banking and lead shields were used to minimize testicular dose during radiation therapy. To minimize imaging artifacts, kilovoltage CT (kVCT) treatment planning was conducted without shielding. Generous hypothetical contours were generated on each 'planning scan' to estimate the location of the lead shield and generate a directionally blocked helical tomotherapy plan. To ensure the accuracy of each plan, megavoltage fan-beam CT (MVCT) scans were obtained at the first treatment and adaptive planning was performed to account for lead shield placement. Two important regions of interest in these cases were femurs and femoral heads. During adaptive planning for the first patient, it was observed that the virtual lead shield contour on kVCT planning images was significantly larger than the actual lead shield used for treatment. However, for the second patient, it was noted that the size of the virtual lead shield contoured on the kVCT image was significantly smaller than the actual shield size. Thus, new adaptive plans based on MVCT images were generated and used for treatment. The planning target volume was underdosed up to 2% and had higher maximum doses without adaptive planning. In conclusion, the treatment of the upper thigh, particularly in young men, presents several clinical challenges, including preservation of gonadal function. In such circumstances, adaptive planning using MVCT can ensure accurate dose delivery even in the presence of high-density testicular shields.

  19. Preoperative Single Fraction Partial Breast Radiotherapy for Early-Stage Breast Cancer

    SciTech Connect

    Palta, Manisha; Yoo, Sua; Adamson, Justus D.; Prosnitz, Leonard R.; Horton, Janet K.

    2012-01-01

    Purpose: Several recent series evaluating external beam accelerated partial breast irradiation (PBI) have reported adverse cosmetic outcomes, possibly related to large volumes of normal tissue receiving near-prescription doses. We hypothesized that delivery of external beam PBI in a single fraction to the preoperative tumor volume would be feasible and result in a decreased dose to the uninvolved breast compared with institutional postoperative PBI historical controls. Methods and Materials: A total of 17 patients with unifocal Stage T1 breast cancer were identified. Contrast-enhanced subtraction magnetic resonance images were loaded into an Eclipse treatment planning system and used to define the target volumes. A 'virtual plan' was created using four photon beams in a noncoplanar beam arrangement and optimized to deliver 15 Gy to the planning target volume. Results: The median breast volume was 1,713 cm{sup 3} (range: 1,014-2,140), and the median clinical target volume was 44 cm{sup 3} (range: 26-73). In all cases, 100% of the prescription dose covered 95% of the clinical target volume. The median conformity index was 0.86 (range: 0.70-1.12). The median percentage of the ipsilateral breast volume receiving 100% and 50% of the prescribed dose was 3.8% (range: 2.2-6.9) and 13.3% (range: 7.5-20.8) compared with 18% (range: 3-42) and 53% (range: 24-65) in the institutional historical controls treated with postoperative external beam PBI (p = .002). The median maximum skin dose was 9 Gy. The median dose to 1 and 10 cm{sup 3} of skin was 6.7 and 4.9 Gy. The doses to the heart and ipsilateral lung were negligible. Conclusion: Preoperative PBI resulted in a substantial reduction in ipsilateral breast tissue dose compared with postoperative PBI. The skin dose appeared reasonable, given the small volumes. A prospective Phase I trial evaluating this technique is ongoing.

  20. Rectal Motion in Patients Receiving Preoperative Radiotherapy for Carcinoma of the Rectum

    SciTech Connect

    Brierley, James D.; Dawson, Laura A.; Sampson, Elliott; Bayley, Andrew; Scott, Sandra; Moseley, Joanne L.; Craig, Timothy; Cummings, Bernard; Dinniwell, Robert; Kim, John J.; Ringash, Jolie; Wong, Rebecca; Brock, Kristy K.

    2011-05-01

    Purpose: To assess the movement of rectum, mesorectum, and rectal primary during a course of preoperative chemoradiotherapy. Methods and Materials: Seventeen patients with Stage II or III rectal cancer had a planning CT scan with rectal contrast before commencement of preoperative chemoradiation. The scan was repeated during Weeks 1, 3, and 5 of chemoradiation. The rectal primary (gross tumor volume), rectum, mesorectum, and bladder were contoured on all four scans. An in-house biomechanical model-based deformable image registration technique, Morfeus, was used to measure the three-dimensional spatial change in these structures after bony alignment. The required planning target volume margin for this spatial change, after bone alignment, was also calculated. Results: Rectal contrast was found to introduce a systematic error in the position of all organs compared with the noncontrast state. The largest change in structures during radiotherapy was in the anterior and posterior directions for the mesorectum and rectum and in the superior and inferior directions for the gross tumor volume. The planning target volume margins required for internal movement for the mesorectum based on the three scans acquired during treatment are 4 mm right, 5 mm left, 7 mm anterior, and 6 mm posterior. For the rectum, values were 8 mm right, 8 mm left, 8 mm anterior, and 9 mm posterior. The greatest movement of the rectum occurred in the upper third. Conclusions: Contrast is no longer used in CT simulation. Assuming bony alignment, a nonuniform margin of 8 mm anteriorly, 9 mm posteriorly, and 8 mm left and right is recommended.

  1. Preoperative evaluation of a patient for abdominal aortic aneurysm repair.

    PubMed Central

    Chonchubhair, A. N.; Cunningham, A. J.

    1998-01-01

    Coexistent cardiovascular disease is common in patients presenting for repair of aortic aneurysms. However, preoperative cardiac evaluation prior to abdominal aortic aneurysm (AAA) surgery remains contentious with significant variations in practice between countries, institutions and individual anesthetists. The following case report raises some everyday issues confronting clinical anesthetists. PMID:10604782

  2. The Role of Preoperative TIPSS to Facilitate Curative Gastric Surgery

    SciTech Connect

    Norton, S.A.; Vickers, J.; Callaway, M.P. Alderson, D.

    2003-08-15

    The use of TIPSS to facilitate radical curative upper gastrointestinal surgery has not been reported. We describe a case in which curative gastric resection was performed for carcinoma of the stomach after a preoperative TIPSS and embolization of a large gastric varix in a patient with portal hypertension.

  3. The effect of preoperative education on anxiety of open cardiac surgery patients.

    PubMed

    Asilioglu, Kezban; Celik, Sevilay Senol

    2004-04-01

    The purpose of this experimental study was to evaluate the effect of preoperative teaching method on anxiety levels of the patients. This study consisted of 100 patients having open cardiac surgery. Of 100 patients 50 were placed in the intervention group while the remaining 50 were in the control group. The patients in the intervention group were given a planned teaching according to the patient education booklet. Patients in the control group were informed about pre- and postoperative routines by a nurse by the purpose of comparing anxiety levels of the patients in the intervention and control groups. The anxiety level of the patients in control and intervention groups was measured on the 3rd day after the operation by using the Self-Evaluation Questionnaire for State and Trait Anxiety Inventory. The mean postoperative state and trait anxiety score in the control group was slightly higher than the mean of the patients in the intervention group. There was no statistically significant difference in the state and trait anxiety scores between the groups, and the patients in the intervention group had lower scores than the patients in the control group. In addition, all patients in the intervention group stated that they were satisfied with the preoperative teaching given by the researcher. PMID:15062906

  4. Images in plastic surgery: digital thermographic photography ("thermal imaging") for preoperative perforator mapping.

    PubMed

    Chubb, Daniel; Rozen, Warren M; Whitaker, Iain S; Ashton, Mark W

    2011-04-01

    Preoperative imaging to identify the location of individual perforators has been shown to improve operative outcomes, and while computed tomographic angiography (CTA) and magnetic resonance angiography are currently the most widely used modalities, these have substantial limitations. Such limitations include the need for intravenous access, the need for iodinated contrast media, radiation exposure with CTA, and long scanning times with magnetic resonance angiography. Complications from the use of contrast media are also noteworthy, and can include anaphylactoid reactions and renal toxicity. In a move to avoid these problems, we have recently introduced a technique that is readily available and easy to implement for preoperative imaging, and may show an accuracy that matches the more advanced imaging modalities. Thermal imaging is a readily performed technique, and can be undertaken by the reconstructive surgeon themselves at the initial consultation, enabling prompt operative planning, and avoiding the need for delays in imaging, confusion in the interpretation of a radiologist report, and the need for an intermediary radiologist altogether. In our experience thus far, the technique matches the accuracy for location of CTA, and a larger clinical trial of the technique is underway. PMID:21389801

  5. Value of flexible bronchoscopy in the pre-operative work-up of solitary pulmonary nodules.

    PubMed

    Schwarz, Carsten; Schönfeld, Nicolas; Bittner, Roland C; Mairinger, Thomas; Rüssmann, Holger; Bauer, Torsten T; Kaiser, Dirk; Loddenkemper, Robert

    2013-01-01

    The diagnostic value of flexible bronchoscopy in the pre-operative work-up of solitary pulmonary nodules (SPN) is still under debate among pneumologists, radiologists and thoracic surgeons. In a prospective observational manner, flexible bronchoscopy was routinely performed in 225 patients with SPN of unknown origin. Of the 225 patients, 80.5% had lung cancer, 7.6% had metastasis of an extrapulmonary primary tumour and 12% had benign aetiology. Unsuspected endobronchial involvement was found in 4.4% of all 225 patients (or in 5.5% of patients with lung cancer). In addition, flexible bronchoscopy clarified the underlying aetiology in 41% of the cases. The bronchoscopic biopsy results from the SPN were positive in 84 (46.5%) patients with lung cancer. Surgery was cancelled due to the results of flexible bronchoscopy in four cases (involvement of the right main bronchus (impaired pulmonary function did not allow pneumonectomy) n=1, small cell lung cancer n=1, bacterial pneumonia n=2), and the surgical strategy had to be modified to bilobectomy in one patient. Flexible bronchoscopy changed the planned surgical approach in five cases substantially. These results suggest that routine flexible bronchoscopy should be included in the regular pre-operative work-up of patients with SPN. PMID:22496316

  6. Image-guided preoperative prediction of pyramidal tract side effect in deep brain stimulation

    NASA Astrophysics Data System (ADS)

    Baumgarten, C.; Zhao, Y.; Sauleau, P.; Malrain, C.; Jannin, P.; Haegelen, C.

    2016-03-01

    Deep brain stimulation of the medial globus pallidus is a surgical procedure for treating patients suffering from Parkinson's disease. Its therapeutic effect may be limited by the presence of pyramidal tract side effect (PTSE). PTSE is a contraction time-locked to the stimulation when the current spreading reaches the motor fibers of the pyramidal tract within the internal capsule. The lack of side-effect predictive model leads the neurologist to secure an optimal electrode placement by iterating clinical testing on an awake patient during the surgical procedure. The objective of the study was to propose a preoperative predictive model of PTSE. A machine learning based method called PyMAN (for Pyramidal tract side effect Model based on Artificial Neural network) that accounted for the current of the stimulation, the 3D electrode coordinates and the angle of the trajectory, was designed to predict the occurrence of PTSE. Ten patients implanted in the medial globus pallidus have been tested by a clinician to create a labeled dataset of the stimulation parameters that trigger PTSE. The kappa index value between the data predicted by PyMAN and the labeled data was .78. Further evaluation studies are desirable to confirm whether PyMAN could be a reliable tool for assisting the surgeon to prevent PTSE during the preoperative planning.

  7. Colorectal Stenting: An Effective Therapy for Preoperative and Palliative Treatment

    SciTech Connect

    Jost, Rahel S. Jost, Res; Schoch, Erich; Brunner, Brigit; Decurtins, Marco; Zollikofer, Christoph L.

    2007-06-15

    Purpose. To demonstrate the effectiveness of preoperative and palliative colorectal stent placement in acute colonic obstruction. Methods. Sixty-seven consecutive patients (mean age 67.3 years, range 25-93 years) with clinical and radiological signs of colonic obstruction were treated: 45 (67%) preoperatively and 22 (33%) with a palliative intent. In 59 patients (88%) the obstruction was malignant, while in 8 (12%) it was benign. A total of 73 enteric Wallstents were implanted under combined fluoroscopic/endoscopic guidance. Results. Forty-five patients were treated preoperatively with a technical success rate of 84%, a clinical success rate of 83%, and a complication rate of 16%. Of the 38 patients who were successfully stented preoperatively, 36 (95%) underwent surgery 2-22 days (mean 7.2 days) after stent insertion. The improved general condition and adequate bowel cleansing allowed single-stage tumor resection and primary end-to-end anastomosis without complications in 31 cases (86% of all operations), while only 5 patients had colostomies. Stent placement was used as the final palliative treatment in 22 patients. The technical success rate was 95%, the clinical success rate 72%, and the complication rate relatively high at 67%, caused by reocclusion in most cases. After noninvasive secondary interventions (e.g., tube placement, second stenting, balloon dilatation) the secondary patency of stents was 71% and mean reported survival time after stent insertion was 92 days (range 10-285 days). Conclusion. Preoperative stent placement in acute colonic obstruction is minimally invasive and allows an elective one-stage surgery in most cases. Stent placement also proved a valuable alternative to avoid colostomy in palliation.

  8. [The randomized study of efficiency of preoperative photodynamic].

    PubMed

    Akopov, A L; Rusanov, A A; Molodtsova, V P; Gerasin, A V; Kazakov, N V; Urtenova, M A; Chistiakov, I V

    2013-01-01

    The authors made a prospective randomized comparison of results of preoperative photodynamic therapy (PhT) with chemotherapy, preoperative chemotherapy in initial unresectable central non-small cell lung cancer in stage III. The efficiency and safety of preoperative therapy were estimated as well as the possibility of subsequent surgical treatment. The research included patients in stage IIIA and IIIB of central non-small cell lung cancer with lesions of primary bronchi and lower section of the trachea, which initially were unresectable, but potentially the patients could be operated on after preoperative treatment. The photodynamic therapy was performed using chlorine E6 and the light of wave length 662 nm. Since January 2008 till December 2011,42 patients were included in the research, 21 patients were randomized in the group for photodynamic therapy and 21--in group without PhT. These groups were compared according to their sex, age, stage of the disease and histological findings. After nonadjuvant treatment the remissions were reached in 19 (90%) patients of the group with PhT and in 16 (76%) patients without PhT and all the patients were operated on. The explorative operations were made on 3 patients out of 16 operated on in the group without PhT (19%). In the group PhT 14 pneumonectomies and 5 lobectomies were perfomed opposite 10 pneumonectomies and 3 lobectomies in group without PhT. The degree of radicalism of resection appears to be reliably higher in the group PhT (RO-89%, R1-11% as against RO-54%, R1-46% in group without PhT), p = 0.038. The preoperative endobronchial PhT conducted with chemotherapy was characterized by efficiency and safety, allowed the surgical treatment and elevated the degree of radicalism of this treatment in selected patients, initially assessed as unresectable. PMID:23808222

  9. Clinical target volume delineation in glioblastomas: pre-operative versus post-operative/pre-radiotherapy MRI

    PubMed Central

    Farace, P; Giri, M G; Meliadò, G; Amelio, D; Widesott, L; Ricciardi, G K; Dall'Oglio, S; Rizzotti, A; Sbarbati, A; Beltramello, A; Maluta, S; Amichetti, M

    2011-01-01

    Objectives Delineation of clinical target volume (CTV) is still controversial in glioblastomas. In order to assess the differences in volume and shape of the radiotherapy target, the use of pre-operative vs post-operative/pre-radiotherapy T1 and T2 weighted MRI was compared. Methods 4 CTVs were delineated in 24 patients pre-operatively and post-operatively using T1 contrast-enhanced (T1PRECTV and T1POSTCTV) and T2 weighted images (T2PRECTV and T2POSTCTV). Pre-operative MRI examinations were performed the day before surgery, whereas post-operative examinations were acquired 1 month after surgery and before chemoradiation. A concordance index (CI) was defined as the ratio between the overlapping and composite volumes. Results The volumes of T1PRECTV and T1POSTCTV were not statistically different (248 ± 88 vs 254 ± 101), although volume differences >100 cm3 were observed in 6 out of 24 patients. A marked increase due to tumour progression was shown in three patients. Three patients showed a decrease because of a reduced mass effect. A significant reduction occurred between pre-operative and post-operative T2 volumes (139 ± 68 vs 78 ± 59). Lack of concordance was observed between T1PRECTV and T1POSTCTV (CI = 0.67 ± 0.09), T2PRECTV and T2POSTCTV (CI = 0.39 ± 0.20) and comparing the portion of the T1PRECTV and T1POSTCTV not covered by that defined on T2PRECTV images (CI = 0.45 ± 0.16 and 0.44 ± 0.17, respectively). Conclusion Using T2 MRI, huge variations can be observed in peritumoural oedema, which are probably due to steroid treatment. Using T1 MRI, brain shifts after surgery and possible progressive enhancing lesions produce substantial differences in CTVs. Our data support the use of post-operative/pre-radiotherapy T1 weighted MRI for planning purposes. PMID:21045069

  10. Preoperative treatment with radiochemotherapy for locally advanced gastroesophageal junction cancer and unresectable locally advanced gastric cancer

    PubMed Central

    Ratosa, Ivica; Oblak, Irena; Anderluh, Franc; Velenik, Vaneja; But-Hadzic, Jasna; Ermenc, Ajra Secerov; Jeromen, Ana

    2015-01-01

    Background. To purpose of the study was to analyze the results of preoperative radiochemotherapy in patients with unresectable gastric or locoregionally advanced gastroesophageal junction (GEJ) cancer treated at a single institution. Patients and methods. Between 1/2004 and 6/2012, 90 patients with locoregionally advanced GEJ or unresectable gastric cancer were treated with preoperative radiochemotherapy at the Institute of Oncology Ljubljana. Planned treatment schedule consisted of induction chemotherapy with 5-fluorouracil and cisplatin, followed by concomitant radiochemotherapy four weeks later. Three-dimensional conformal external beam radiotherapy was delivered by dual energy (6 and 15 MV) linear accelerator in 25 daily fractions of 1.8 Gy in 5 weeks with two additional cycles of chemotherapy repeated every 28 days. Surgery was performed 4–6 weeks after completing radiochemotherapy. Following the surgery, multidisciplinary advisory team reassessed patients for the need of adjuvant chemotherapy. The primary endpoints were histopathological R0 resection rate and pathological response rate. The secondary endpoints were toxicity of preoperative radiochemotherapy and survival. Results. Treatment with preoperative radiochemotherapy was completed according to the protocol in 84 of 90 patients (93.3%). Twenty patients (22.2%) did not undergo the surgery because of the disease progression, serious comorbidity, poor performance status or still unresectable tumour. In 13 patients (14.4%) only exploration was performed because the tumour was assessed as unresectable or diffuse peritoneal carcinomatosis was established. Fifty-seven patients (63.4%) underwent surgery with the aim of complete removal of the tumour. Radical resection was achieved in 50 (55.6%) patients and the remaining seven (7.8%) patients underwent non-radical surgery (R1 in five and R2 in two patients). In this group of patients (n = 57), pathological complete response of tumour was achieved in five

  11. Predict amine solution properties accurately

    SciTech Connect

    Cheng, S.; Meisen, A.; Chakma, A.

    1996-02-01

    Improved process design begins with using accurate physical property data. Especially in the preliminary design stage, physical property data such as density viscosity, thermal conductivity and specific heat can affect the overall performance of absorbers, heat exchangers, reboilers and pump. These properties can also influence temperature profiles in heat transfer equipment and thus control or affect the rate of amine breakdown. Aqueous-amine solution physical property data are available in graphical form. However, it is not convenient to use with computer-based calculations. Developed equations allow improved correlations of derived physical property estimates with published data. Expressions are given which can be used to estimate physical properties of methyldiethanolamine (MDEA), monoethanolamine (MEA) and diglycolamine (DGA) solutions.

  12. Accurate thickness measurement of graphene

    NASA Astrophysics Data System (ADS)

    Shearer, Cameron J.; Slattery, Ashley D.; Stapleton, Andrew J.; Shapter, Joseph G.; Gibson, Christopher T.

    2016-03-01

    Graphene has emerged as a material with a vast variety of applications. The electronic, optical and mechanical properties of graphene are strongly influenced by the number of layers present in a sample. As a result, the dimensional characterization of graphene films is crucial, especially with the continued development of new synthesis methods and applications. A number of techniques exist to determine the thickness of graphene films including optical contrast, Raman scattering and scanning probe microscopy techniques. Atomic force microscopy (AFM), in particular, is used extensively since it provides three-dimensional images that enable the measurement of the lateral dimensions of graphene films as well as the thickness, and by extension the number of layers present. However, in the literature AFM has proven to be inaccurate with a wide range of measured values for single layer graphene thickness reported (between 0.4 and 1.7 nm). This discrepancy has been attributed to tip-surface interactions, image feedback settings and surface chemistry. In this work, we use standard and carbon nanotube modified AFM probes and a relatively new AFM imaging mode known as PeakForce tapping mode to establish a protocol that will allow users to accurately determine the thickness of graphene films. In particular, the error in measuring the first layer is reduced from 0.1-1.3 nm to 0.1-0.3 nm. Furthermore, in the process we establish that the graphene-substrate adsorbate layer and imaging force, in particular the pressure the tip exerts on the surface, are crucial components in the accurate measurement of graphene using AFM. These findings can be applied to other 2D materials.

  13. 77 FR 70484 - Preoperational Testing of Onsite Electric Power Systems To Verify Proper Load Group Assignments...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-26

    ... COMMISSION Preoperational Testing of Onsite Electric Power Systems To Verify Proper Load Group Assignments... for public comment draft regulatory guide (DG), DG-1294, ``Preoperational Testing of On-Site Electric... encompass preoperational testing of electrical power systems used to meet current Station...

  14. The Prognostic Importance of Patient Pre-Operative Expectations of Surgery for Lumbar Spinal Stenosis.

    ERIC Educational Resources Information Center

    Iversen, Maura D.; Daltroy, Lawren H.; Fossel, Anne H.; Katz, Jeffrey N.

    1998-01-01

    Examines patients (N=257) with lumbar spinal stenosis preoperatively and at six months to relate patient expectation to baseline function and pain and to determine how patient expectations and preoperative function interact to predict postoperative outcomes. Results show that patients with many preoperative expectations, particularly those with…

  15. Preoperative multidisciplinary treatment with hyperthermia for soft tissue sarcoma.

    PubMed

    Makihata, E; Kuroda, M; Kawai, A; Ozaki, T; Sugihara, S; Inoue, H; Joja, I; Asaumi, J; Kawasaki, S; Hiraki, Y

    1997-04-01

    We report the results of phase I/II studies of preoperative multidisciplinary treatment of 14 patients with soft tissue sarcoma using hyperthermia from November 1990 to April 1995. The preoperative treatment was conducted with thermo-radio-chemotherapy in 11 cases of stage III, and with thermo-radiotherapy as well as thermo-chemotherapy in three cases of stages I and II. Hyperthermia was carried out twice a week with totals ranging from 4 to 14 times (average: 8.4 times); each session lasted 60 min. Radiotherapy was administered four or five times per week, and the dose was 1.8 2Gy/fraction, with a total of 30-40 Gy in a four week period. Chemotherapy was mainly in the form of MAID regimen (2-mercaptoethanesulphonic acid (mesna), adriamycin, ifosfamide and dacarbazine). The tumors were surgically resected in all patients after completing the preoperative treatment. The efficacy rate, as expressed by the percentage of either tumors in which reduction rate was 50% or more, or tumors for which post-treatment contrast enhanced CT image revealed low density volumes occupying 50% or more of the total mass, was 71% (ten of the 14 tumors). The mean tumor necrosis rate in the resected specimens was 78%. The tumor necrosis rate was significantly high (P < 0.05) in patients whose Time > or = 42 degrees C was of long duration. Postoperative complications were observed in six patients; among these, two patients developed wound infection that required surgical treatment as a complication of surgery performed in the early stage following the preoperative treatment. After a mean postoperative follow-up of 27 months, distant metastasis occurred in four patients resulting in three fatalities. The three-year cumulative survival rate was 64.3%. No local recurrence was observed in any patient during the follow-up, thus confirming our hypothesis that preoperative multidisciplinary treatment has an excellent local efficacy. We think that it would be valuable to conduct, at many

  16. Preoperative discussion with patients about delirium risk: are we doing enough?

    PubMed

    Tomlinson, Judith H; Partridge, Judith S L

    2016-01-01

    Postoperative delirium is a common complication in the older surgical population, occurring in 10-50 % of cases. It is thought to be more common if an individual is identified as frail. Postoperative delirium is associated with poor outcome including higher mortality rates, prolonged length of hospital stay, increased care needs on discharge and longer term post-traumatic stress disorder. Guidelines from the American Geriatric Society and the National Institute for Health and Care Excellence highlight the importance of risk assessment at the time of the preoperative visit. This enables the perioperative team to plan a care pathway that minimises the risk of delirium occurring postoperatively. Risk assessment also informs a discussion with patient and family regarding their risk, as part of a process of informed patient consent. This is an essential step in conforming to current legal and General Medical Council guidance on the process of consent. PMID:27594990

  17. The value of the preoperative barium-enema examination in the assessment of pelvic masses

    SciTech Connect

    Gedgaudas, R.K.; Kelvin, F.M.; Thompson, W.M.; Rice, R.P.

    1983-03-01

    The value of the barium-enema examination in the assessment of pelvic masses was studied in 44 patients. Findings from those barium-enema examinations and from pathological specimens from 37 patients who had malignant tumors and seven patients who had endometriosis were retrospectively analyzed to determine if the barium-enema examination is useful in differentiating extrinsic lesions with and without invasion of the colon. None of the 12 patients who had extrinsic lesions had any of the criteria that indicated bowel-wall invasion. These criteria included fixation and serrations of the bowel wall in all patients with invasion, and ulceration and fistulizaton in those patients who had complete transmural invasion. In patients with pelvic masses, the preoperative barium-enema examination may be useful to the surgeon in planning surgery and in preparing the patient for the possibility of partial colectomy or colostomy.

  18. Aorta-Left Renal Vein Fistula Complicating an Aortic Aneurysm: Preoperative and Postoperative Multislice CT Findings

    SciTech Connect

    Barrier, Pierre Otal, Philippe; Garcia, Olivier; Vahdat, Olivier; Domenech, Brice; Lannareix, Valerie; Joffre, Francis; Rousseau, Herve

    2007-06-15

    Fistulas complicating an abdominal aortic aneurysm (AAA) are rare, and fistulas involving the left renal vein are particularly uncommon. We highlight here a fistula between an infrarenal aortic aneurysm and a retroaortic left renal vein, revealed by left flank pain associated with hematuria and acute renal failure. The multislice CT angiography performed in this 68-year-old patient revealed communication and equal enhancement between the aorta and the left gonadic vein, suggesting the presence of a fistula. The three-dimensional VRT reconstructions presented in this case were of great value in the preoperative planning, enabling immediate visualization of this unusual feature. Alternative diagnoses to consider when encountering this clinical presentation are reviewed.

  19. Resting-State Blood Oxygen Level-Dependent Functional MRI: A Paradigm Shift in Preoperative Brain Mapping.

    PubMed

    Leuthardt, Eric C; Allen, Monica; Kamran, Mudassar; Hawasli, Ammar H; Snyder, Abraham Z; Hacker, Carl D; Mitchell, Timothy J; Shimony, Joshua S

    2015-01-01

    Currently, functional magnetic resonance imaging (fMRI) facilitates a preoperative awareness of an association of an eloquent region with a tumor. This information gives the neurosurgeon helpful information that can aid in creating a surgical strategy. Typically, task-based fMRI has been employed to preoperatively localize speech and motor function. Task-based fMRI depends on the patient's ability to comply with the task paradigm, which often is impaired in the setting of a brain tumor. This problem is overcome by using resting-state fMRI (rs-fMRI) to localize function. rs-fMRI measures spontaneous fluctuations in the blood oxygen level-dependent (BOLD) signal, representing the brain's functional organization. In a neurosurgical context, it allows noninvasive simultaneous assessment of multiple large-scale distributed networks. Compared with task-related fMRI, rs-fMRI provides more comprehensive information on the functional architecture of the brain and is applicable in settings where task-related fMRI may provide inadequate information or could not be performed. Taken together, rs-fMRI substantially expands the preoperative mapping capability in efficiency, effectiveness, and scope. In this article, a brief introduction into rs-fMRI processing methods is followed by a detailed discussion on the role rs-fMRI plays in presurgical planning. PMID:26784290

  20. The Role of Preoperative Evaluation for Congenital Methemoglobinemia

    PubMed Central

    Kuş, Alparslan; Berk, Derya; Hoşten, Tülay; Gürkan, Yavuz; Solak, Mine; Toker, Kamil

    2014-01-01

    Preoperative care includes a clinical examination before invasive or non-invasive interventions for anaesthesia/analgesia and is the responsibility of the anaesthesiologists. Methemoglobinemia should be considered, as well as cardiac, pulmonary, and peripheral circulatory disorders in patients with central cyanosis and low oxygen saturation despite treatment with sufficient oxygen during anaesthesia. Methemoglobinemia is a serious clinical condition, associated with increased blood methemoglobin levels characterized by clinical signs, such as cyanosis and hypoxia due to lack of oxygen-carrying capacity. Here, we present our anaesthesia management in a patient with unnoticed congenital methemoglobinemia during preoperative evaluation, in whom clinical signs of methemoglobinemia developed after local anaesthesia administration before the surgery. PMID:27366424

  1. Preoperative Predictors of Pain Following Total Knee Arthroplasty

    PubMed Central

    Noiseux, Nicolas O.; Callaghan, John J.; Clark, Charles R.; Zimmerman, M. Bridget; Sluka, Kathleen A.; Rakel, Barbara A.

    2014-01-01

    Total knee arthroplasty has provided dramatic improvements in function and pain for the majority of patients with knee arthritis, yet a significant proportion of patients remain dissatisfied with their results. We performed a prospective analysis of 215 patients undergoing TKA who underwent a comprehensive array of evaluations to discover whether any preoperative assessment could predict high pain scores and functional limitations postoperatively. Patients with severe pain with a simple knee range-of-motion test prior to TKA had a 10x higher likelihood of moderate to severe pain at 6 months. A simple test of pain intensity with active flexion and extension preoperatively was a significant predictor of postoperative pain at 6 months after surgery. Strategies to address this particular patient group may improve satisfaction rates of TKA. PMID:24630598

  2. Preoperative cardiovascular investigations in liver transplant candidate: An update

    PubMed Central

    Sehgal, Lalit; Srivastava, Piyush; Pandey, Chandra Kant; Jha, Amit

    2016-01-01

    Cardiovascular complications are a major cause of morbidity and mortality in patients with end-stage liver disease (ESLD) undergoing liver transplantation. Identifying candidates at the highest risk of postoperative cardiovascular complications is the cornerstone for optimizing the outcome. Ischaemic heart disease contributes to major portion of cardiovascular complications and therefore warrants evaluation in the preoperative period. Patients of ESLD usually demonstrate increased cardiac output, compromised ventricular response to stress, low systemic vascular resistance and occasionally bradycardia. Despite various recommendations for preoperative evaluation of cardiovascular disease in liver transplant candidates, a considerable controversy on screening methodology persists. This review critically focuses on the rapidly expanding body of evidence for diagnosis and risk stratification of cardiovascular disorder in liver transplant candidates. PMID:26962249

  3. The concept of death in preoperational retarded children.

    PubMed

    Sternlicht, M

    1980-12-01

    Fourteen preoperational retarded boys and girls (mean MA = 6-4), as classified by the failure to pass three conservation tasks, were interviewed for their concepts of death, with Koocher's (1973) study used as a model. Each S was asked, "What makes things die?" "How can you make dead things come back to life?" "When will you die?" and "What will happen then?" It was found that the preoperational retarded Ss did not have realistic concepts of when they will die, or of the permanence of death. They did, however, have realistic notions of how things die. It was also found that the types of replies made to these questions were related to their cognitive level (p less than .01). PMID:7205203

  4. Essential elements of the preoperative breast reconstruction evaluation.

    PubMed

    Cheng, Angela; Losken, Albert

    2015-04-01

    A plethora of options exist for breast reconstruction and preoperative evaluation must be thorough to lead to a successful outcome. We review multiple components of the preoperative assessment including the patient's history, goals, imaging, and key elements of the physical exam. Consideration for tumor biology, staging, need or response to chemotherapy or radiation therapy is important in deciding on immediate versus delayed reconstruction. It is also important to consider the patient's anatomy, breast size and whether the reconstruction will be unilateral or bilateral. The reconstructive surgeon must accommodate all these factors to consider partial or complete mastectomy defects and guide the patient to the most appropriate reconstructive technique whether it be an oncoplastic reduction mammoplasty, expander-based reconstruction, immediate implant reconstruction, or immediate versus delayed autologous tissue reconstruction such as the deep inferior epigastric artery perforator (DIEP)/transverse rectus abdominis muscle (TRAM), latissimus, transverse upper gracilis (TUG)/profunda femoris artery perforator (PAP), or gluteal artery perforator (GAP) flaps. PMID:26005641

  5. Accurate ab Initio Spin Densities

    PubMed Central

    2012-01-01

    We present an approach for the calculation of spin density distributions for molecules that require very large active spaces for a qualitatively correct description of their electronic structure. Our approach is based on the density-matrix renormalization group (DMRG) algorithm to calculate the spin density matrix elements as a basic quantity for the spatially resolved spin density distribution. The spin density matrix elements are directly determined from the second-quantized elementary operators optimized by the DMRG algorithm. As an analytic convergence criterion for the spin density distribution, we employ our recently developed sampling-reconstruction scheme [J. Chem. Phys.2011, 134, 224101] to build an accurate complete-active-space configuration-interaction (CASCI) wave function from the optimized matrix product states. The spin density matrix elements can then also be determined as an expectation value employing the reconstructed wave function expansion. Furthermore, the explicit reconstruction of a CASCI-type wave function provides insight into chemically interesting features of the molecule under study such as the distribution of α and β electrons in terms of Slater determinants, CI coefficients, and natural orbitals. The methodology is applied to an iron nitrosyl complex which we have identified as a challenging system for standard approaches [J. Chem. Theory Comput.2011, 7, 2740]. PMID:22707921

  6. Preoperative easily misdiagnosed telangiectatic osteosarcoma: clinical–radiologic–pathologic correlations

    PubMed Central

    Gao, Zhen-Hua; Yin, Jun-Qiang; Liu, Da-Wei; Meng, Quan-Fei

    2013-01-01

    Abstract Purpose: To describe the clinical, imaging, and pathologic characteristics and diagnostic methods of telangiectatic osteosarcoma (TOS) for improving the diagnostic level. Materials and methods: The authors retrospectively reviewed patient demographics, serum alkaline phosphatase (AKP) levels, preoperative biopsy pathologic reports, pathologic materials, imaging findings, and treatment outcomes from 26 patients with TOS. Patient images from radiography (26 cases) and magnetic resonance (MR) imaging (22 cases) were evaluated by 3 authors in consensus for intrinsic characteristics. There were 15 male and 11 female patients in the study, with an age of 9–32 years (mean age 15.9 years). Results: Eighteen of 26 patients died of lung metastases within 5 years of follow-up. The distal femur was affected more commonly (14 cases, 53.8%). Regarding serum AKP, normal (8 cases) or mildly elevated (18 cases) levels were found before preoperative chemotherapy. Radiographs showed geographic bone lysis without sclerotic margin (26 cases), cortical destruction (26 cases), periosteal new bone formation (24 cases), soft-tissue mass (23 cases), and matrix mineralization (4 cases). The aggressive radiographic features of TOS simulated the appearance of conventional high-grade intramedullary osteosarcoma, though different from aneurysmal bone cyst. MR images demonstrated multiple big (16 cases) or small (6 cases) cystic spaces, fluid-fluid levels (14 cases), soft-tissue mass (22 cases), and thick peripheral and septal enhancement (22 cases). Nine of 26 cases were misdiagnosed as aneurysmal bone cysts by preoperative core-needle biopsy, owing to the absence of viable high-grade sarcomatous cells in the small tissue samples. Conclusion: The aggressive growth pattern with occasional matrix mineralization, and multiple big or small fluid-filled cavities with thick peripheral, septal, and nodular tissue surrounding the fluid-filled cavities are characteristic imaging features of

  7. Preoperative embolization of primary bone tumors: A case control study

    PubMed Central

    Jha, Roushan; Sharma, Raju; Rastogi, Shishir; Khan, Shah Alam; Jayaswal, Arvind; Gamanagatti, Shivanand

    2016-01-01

    AIM: To study the safety and effectiveness of preoperative embolization of primary bone tumors in relation to intraoperative blood loss, intraoperative blood transfusion volume and surgical time. METHODS: Thirty-three patients underwent preoperative embolization of primary tumors of extremities, hip or vertebrae before resection and stabilization. The primary osseous tumors included giant cell tumors, aneurysmal bone cyst, osteoblastoma, chondroblastoma and chondrosarcoma. Twenty-six patients were included for the statistical analysis (embolization group) as they were operated within 0-48 h within preoperative embolization. A control group (non-embolization group, n = 28) with bone tumor having similar histological diagnosis and operated without embolization was retrieved from hospital record for statistical comparison. RESULTS: The mean intraoperative blood loss was 1300 mL (250-2900 mL), the mean intraoperative blood transfusion was 700 mL (0-1400 mL) and the mean surgical time was 221 ± 76.7 min for embolization group (group I, n = 26). Non-embolization group (group II, n = 28), the mean intraoperative blood loss was 1800 mL (800-6000 mL), the mean intraoperative blood transfusion was 1400 mL (700-8400 mL) and the mean surgical time was 250 ± 69.7 min. On comparison, statistically significant (P < 0.001) difference was found between embolisation group and non-embolisation group for the amount of blood loss and requirement of blood transfusion. There was no statistical difference between the two groups for the surgical time. No patients developed any angiography or embolization related complications. CONCLUSION: Preoperative embolization of bone tumors is a safe and effective adjunct to the surgical management of primary bone tumors that leads to reduction in intraoperative blood loss and blood transfusion volume. PMID:27158424

  8. Preoperative risk factors in recurrent endometrioma after primary conservative surgery

    PubMed Central

    Chon, Seung Joo; Lee, Seung Hyeong; Choi, Joo Hyun

    2016-01-01

    Objective Endometriosis is a common gynecological disorder caused by ectopic implantation of endometrial glandular and stromal cells outside the uterine cavity. Among several types of endometriosis, endometrioma is the only subtype that could be determined preoperatively using pelvic ultrasonography, and guidelines recommend pathologic confirmation of endometrioma greater than 3 cm in diameter. However, although surgery is performed in cases of endometrioma, endometrioma has a high cumulative rate of recurrence. Therefore, because determining the possibility of recurrence before performance of initial surgery is important, we examined preoperative factors associated with recurrent endometrioma. Methods This was a retrospective, comparative study including 236 patients who visited the outpatient clinic between January 2009 and December 2011. Patients who were pathologically diagnosed with endometrioma were included in this study. They were followed up postoperatively and were divided into two groups according to presence of recurrent endometrioma. Results We examined associations between baseline factors and recurrent endometrioma. In multivariate analysis, dysmenorrhea and cyst septation were statistically significant after adjusting with age, parity, surgical staging and postoperative management. We examined cumulative recurrence free survival within cases of recurrent endometriosis, based on the presence of inner cyst septation. The cumulative recurrence free survival was lower in cases with septation. Conclusion Our study found that recurrent endometrioma is more likely in patients with inner cyst septation and the recurrence occurred within a shorter duration of time than in patients without inner cyst septation on preoperative ultrasonography. Therefore intensive caution and postoperative long term medical therapy would be appropriate in patients with inner cyst septation on preoperative ultrasonography before undergoing primary surgery for endometrioma. PMID

  9. Total ankle arthroplasty with severe preoperative varus deformity.

    PubMed

    Hanselman, Andrew E; Powell, Brian D; Santrock, Robert D

    2015-04-01

    Advancements in total ankle arthroplasty (TAA) over the past several decades have led to improved patient outcomes and implant survivorship. Despite these innovations, many implant manufacturers still consider a preoperative coronal plane deformity greater than 10° a relative contraindication to TAA. Without proper intraoperative alignment, these implants may experience abnormal wear and hardware failure. Correcting these deformities, often through the use of soft tissue procedures and/or osteotomies, not only increases the difficulty of a case, but also the intraoperative time and radiation exposure. The authors report a case in which a 54-year-old man with a severe right ankle varus deformity of 29° underwent successful TAA using the INBONE II Prophecy total ankle system (Wright Medical Technology, Inc, Memphis, Tennessee) and additional soft tissue reconstruction. Intraoperatively, the patient's coronal deformity was corrected to 1.8°. At 8 months postoperatively, the patient ambulated without restriction and had substantial improvement in validated patient outcome scores, specifically the Academy of Orthopaedic Surgeons Foot and Ankle Module and the Short Form Health Survey-12 This unique report documents the first time that this particular implant, with an exclusive preoperative computed tomography-derived patient-specific guide, has been used effectively for a severe preoperative varus deformity greater than 20° without the need for an osteotomy. Future studies should be directed toward the prospective evaluation of different total ankle implant systems and their outcomes with severe coronal plane deformity, specifically computed tomography-derived patient-specific guided implants. PMID:25901630

  10. [Tonsillectomy in children: preoperative evaluation of risk factors].

    PubMed

    Stuck, B A; Genzwürker, H V

    2008-05-01

    Tonsillectomy is one of the most frequently performed surgical procedures in children and is associated with a relatively high risk of postoperative complications. The question often arises whether paediatric obstructive sleep apnoea should be diagnosed with preoperative sleep testing and whether preoperative coagulation tests should be performed in every child undergoing tonsillectomy. In order to answer these questions, the relevant German and English literature was analysed. Adenotonsillectomy in childhood usually resolves the underlying sleep-related breathing disorder. Nevertheless, especially in children with clinical risk factors such as severe sleep apnoea, obesity or craniofacial malformation, respiratory complications should be expected in the postoperative phase. Routine sleep tests prior to tonsillectomy are neither necessary nor practical for preoperative evaluation. Inherited coagulation disorders have only a limited effect on the occurrence of postoperative bleeding and the predictive value of routine coagulation tests is limited. As long as a thorough clinical history is negative, routine coagulation tests are not helpful or necessary prior to tonsillectomy in children. PMID:18311551

  11. [The evaluation of preoperative anesthetic visit in our hospital].

    PubMed

    Adachi, Y; Watanabe, K; Satoh, T

    1999-09-01

    The preoperative visit by an anesthetist has been thought to be important for the assessment of patient and to communicate with them. However, there are few reports on the visit in Japan until now. The effect of preoperative anesthetic visit in our hospital was estimated by interviewing patients just before surgery who had received a visit by their anesthetist. The answers from sequential 346 scheduled surgical patients for 8 weeks were obtained. Only 72 patients were able to recall the name of their anesthetists. About half of patients believed that anesthetist just had put the patient to sleep and relieved them from pain. We measured the number of treatments each patient could remember that had been explained by the anesthetist on the visit, and found it was unexpectedly small at the interview. These data suggest that our preoperative visit may not be satisfying in view of making good relationship between patients and anesthetists, and educating patients for recent anesthesia. We should make an effort to educate the patients about up-to-date and reasonable anesthesia. PMID:10513187

  12. Preoperative staging of rectal cancer: the MERCURY research project.

    PubMed

    Brown, G; Daniels, I R

    2005-01-01

    The development of a surgical technique that removes the tumour and all local draining nodes in an intact package, namely total mesorectal excision (TME) surgery, has provided the impetus for a more selective approach to the administration of preoperative therapy. One of the most important factors that governs the success of TME surgery is the relationship of tumour to the circumferential resection margin (CRM). Tumour involves the CRM in up to 20% of patients undergoing TME surgery, and results in both poor survival and local recurrence. It is therefore clear that the importance of the decision regarding the use of pre-operative therapy lies with the relationship of the tumour to the mesorectal fascia. In addition, a high-spatial-resolution MRI technique will identify tumours exhibiting other poor prognostic features, namely, extramural spread >5 mm, extramural venous invasion by tumour, nodal involvement, and peritoneal infiltration. The potential benefits of a selective approach using MRI-based selection criteria are evident. That is, over 50% of patients can be treated successfully with primary surgery alone without significant risk of local recurrence or systemic failure. Of the remainder, potentially dramatic improvements may be achieved through the use of intensive and targeted preoperative therapy aimed not only at reducing the size of the primary tumour and rendering potentially irresectable tumour resectable with tumour-free circumferential margins, but also at enabling patients at high risk of systemic failure to benefit from intensive combined modality therapy aimed at eliminating micrometastatic disease. PMID:15865021

  13. Psychologists in preoperative programmes for children undergoing surgery.

    PubMed

    Cuzzocrea, Francesca; Costa, Sebastiano; Gugliandolo, Maria Cristina; Larcan, Rosalba

    2016-06-01

    This study aimed to verify whether psychologists and game activities could reduce preoperative anxiety and promote compliance in paediatric patients. More specifically, we sought to evaluate whether it would be better to propose contextualized games or just distracting activities. A total of 104 children undergoing surgery were assigned to the following 4 conditions of treatment: (1) contextual games and psychological accompaniment, (2) only contextual games, (3) distracting activities, and (4) only psychological accompaniment. Observed children's anxiety was assessed using modified Yale Preoperative Anxiety Scale and compliant behaviours with modified form of Induction Compliance Checklist. Children in the first condition (complete intervention - contextual games and psychological accompaniment) were less anxious and more cooperative in the preoperative period and during the induction of anaesthesia than in the other three conditions. In particular, contextual activities (second condition) were found to be more efficient than psychological accompaniment (fourth condition), whereas the worst condition was proposing only distracting activities (third condition). In order to help young hospitalized patients in paediatric surgery structures, it is necessary to propose games that can prepare them for what will happen as well as the support of a psychologist. PMID:25469004

  14. Learning curve of endorectal ultrasonography in preoperative staging of rectal carcinoma

    PubMed Central

    LIU, ZUO-LIANG; ZHOU, TONG; LIANG, XIAO-BO; MA, JUN-JIE; ZHANG, GUANG-JUN

    2014-01-01

    Accurate preoperative staging of rectal carcinoma is essential for optimal treatment. This study was designed to evaluate the accuracy and learning curve of endorectal ultrasonography (ERUS) in the preoperative staging of rectal carcinoma. We retrospectively analyzed the records of patients with rectal carcinoma who underwent preoperative ERUS followed by curative surgery at the Shanxi Province Tumor Hospital between January, 2007 and March, 2010. The patients were divided into three groups, namely A, B and C, depending on whether the examination was performed between January and December, 2007, between January and December, 2008 or between January, 2009 and March, 2010, respectively. Five physicians with no prior experience in ERUS performed the examinations. We compared the ERUS staging with the pathological findings using the tumor-node-metastasis (TNM) classification. The accuracy of ERUS in T and N staging after each additional consecutive 20 patients was calculated for physicians D, E and F. A total of 319 patients underwent ERUS prior to surgery. There were 38 patients in group A, 135 in group B and 146 in group C. Two of the five physicians performed only 47 of the 319 examinations, whereas the remaining 272 patients were examined by physicians D (n=162), E (n=64) and F (n=46). The overall accuracy in assessing the extent of rectal wall invasion (T) was 67%, with 16% of the cases overstaged and 17% understaged and the accuracy in assessing nodal involvement (N) was 66%, with 11% of the cases overstaged and 23% understaged. The total T and N staging accuracy of physicians D, E and F was 75 and 72%; 59 and 59%; and 50 and 52%, respectively. For physicians D, E and F, the accuracy of T and N staging after each additional 20 patients was calculated and the curve of the accuracy reached a plateau after physician D completed 80 cases. Therefore, ERUS is a valuable tool for assessing the depth of tumor invasion and it appears that after ~80 cases a physician may

  15. Learning curve of endorectal ultrasonography in preoperative staging of rectal carcinoma.

    PubMed

    Liu, Zuo-Liang; Zhou, Tong; Liang, Xiao-Bo; Ma, Jun-Jie; Zhang, Guang-Jun

    2014-11-01

    Accurate preoperative staging of rectal carcinoma is essential for optimal treatment. This study was designed to evaluate the accuracy and learning curve of endorectal ultrasonography (ERUS) in the preoperative staging of rectal carcinoma. We retrospectively analyzed the records of patients with rectal carcinoma who underwent preoperative ERUS followed by curative surgery at the Shanxi Province Tumor Hospital between January, 2007 and March, 2010. The patients were divided into three groups, namely A, B and C, depending on whether the examination was performed between January and December, 2007, between January and December, 2008 or between January, 2009 and March, 2010, respectively. Five physicians with no prior experience in ERUS performed the examinations. We compared the ERUS staging with the pathological findings using the tumor-node-metastasis (TNM) classification. The accuracy of ERUS in T and N staging after each additional consecutive 20 patients was calculated for physicians D, E and F. A total of 319 patients underwent ERUS prior to surgery. There were 38 patients in group A, 135 in group B and 146 in group C. Two of the five physicians performed only 47 of the 319 examinations, whereas the remaining 272 patients were examined by physicians D (n=162), E (n=64) and F (n=46). The overall accuracy in assessing the extent of rectal wall invasion (T) was 67%, with 16% of the cases overstaged and 17% understaged and the accuracy in assessing nodal involvement (N) was 66%, with 11% of the cases overstaged and 23% understaged. The total T and N staging accuracy of physicians D, E and F was 75 and 72%; 59 and 59%; and 50 and 52%, respectively. For physicians D, E and F, the accuracy of T and N staging after each additional 20 patients was calculated and the curve of the accuracy reached a plateau after physician D completed 80 cases. Therefore, ERUS is a valuable tool for assessing the depth of tumor invasion and it appears that after ~80 cases a physician may

  16. A new computational model for human thyroid cancer enhances the preoperative diagnostic efficacy

    PubMed Central

    Li, Tuo; Sheng, Jianguo; Li, Weiqin; Zhang, Xin; Yu, Hongyu; Chen, Xueyun; Zhang, Jianquan; Cai, Quancai; Shi, Yongquan; Liu, Zhimin

    2015-01-01

    Considering the high rate of missed diagnosis and delayed treatments for thyroid cancer, an effective systematic model for the differential diagnosis is highly needed. Thus we analyzed the data on the clinicopathological characteristics, routine laboratory tests and imaging examinations in a cohort of 13,980 patients with thyroid cancer to establish a new diagnostic model for differentiating thyroid cancer in clinical practice. Here, we randomly selected two-thirds of the population to develop the thyroid malignancy risk scoring system (TMRS) for preoperative differentiation between thyroid cancer and benignant thyroid diseases, and then validated its differential diagnostic power in the rest one-third population. The 18 predictors finally enrolled in the TMRS included male gender, clinical manifestations (fever, neck sore, neck lump, palpitations or sweating), laboratory findings (TSH>1.56mIU/L, FT3>5.85pmol/L, TPOAb>14.97IU/ml, TgAb>48.00IU/ml, Tg>34.59μg/L, Ct>64.00ng/L, and CEA>0.41μg/L), and ultrasound features (tumor number≤ 23mm, site, size, echo texture, margins, and shape of neck lymphnodes). The TMRS is validated to be well-calibrated (P = 0.437) and excellently discriminated (AUC = 0.93, 95% CI [0.92, 0.94]), with an accuracy of 83.2%, a sensitivity of 89.3%, a specificity of 81.5%, positive and negative predictive values of 56.8% and 96.6%, positive and negative likelihood ratios of 4.83 and 0.13 in the development cohort, respectively. The TMRS highlights that this differential diagnostic system could help provide accurate preoperative risk stratification for thyroid cancer, and avoid unnecessary over- and under-treatment for such patients. PMID:26325368

  17. Segmentation and reconstruction of cerebral vessels from 3D rotational angiography for AVM embolization planning.

    PubMed

    Li, Fan; Chenoune, Yasmina; Ouenniche, Meriem; Blanc, Raphaël; Petit, Eric

    2014-01-01

    Diagnosis and computer-guided therapy of cerebral Arterio-Venous Malformations (AVM) require an accurate understanding of the cerebral vascular network both from structural and biomechanical point of view. We propose to obtain such information by analyzing three Dimensional Rotational Angiography (3DRA) images. In this paper, we describe a two-step process allowing 1) the 3D automatic segmentation of cerebral vessels from 3DRA images using a region-growing based algorithm and 2) the reconstruction of the segmented vessels using the 3D constrained Delaunay Triangulation method. The proposed algorithm was successfully applied to reconstruct cerebral blood vessels from ten datasets of 3DRA images. This software allows the neuroradiologist to separately analyze cerebral vessels for pre-operative interventions planning and therapeutic decision making. PMID:25571245

  18. Operational Environmental Monitoring Program Quality Assurance Project Plan

    SciTech Connect

    Perkins, C.J.

    1994-08-01

    This Quality Assurance Project Plan addresses the quality assurance requirements for the activities associated with the preoperational and operational environmental monitoring performed by Westinghouse Hanford Company as it implements the Operational Environmental Monitoring program. This plan applies to all sampling and monitoring activities performed by Westinghouse Hanford Company in implementing the Operational Environmental Monitoring program at the Hanford Site.

  19. Providing Preoperative Information for Children Undergoing Surgery: A Randomized Study Testing Different Types of Educational Material to Reduce Children's Preoperative Worries

    ERIC Educational Resources Information Center

    Fernandes, S. C.; Arriaga, P.; Esteves, F.

    2014-01-01

    This study developed three types of educational preoperative materials and examined their efficacy in preparing children for surgery by analysing children's preoperative worries and parental anxiety. The sample was recruited from three hospitals in Lisbon and consisted of 125 children, aged 8-12 years, scheduled to undergo outpatient surgery.…

  20. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  1. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  2. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  3. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  4. 38 CFR 4.46 - Accurate measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  5. Is there a case for selective, rather than routine, preoperative laryngoscopy in thyroid surgery?

    PubMed Central

    González-Sánchez, Carmen; Aguilera-Molina, Yari Yuritzi; Rozo-Coronel, Orlando; Estévez-Alonso, José Santiago; Muñoz-Herrera, Ángel

    2015-01-01

    Background According to some authors, routine preoperative laryngoscopy should be the standard of care in all patients undergoing thyroid surgery. The rationale for this approach is (I) the risk that a patient has a preoperative vocal cord palsy (VCP) without symptoms; (II) the presence of VCP preoperatively is suggestive of invasive malignancy; (III) it is relevant for the use of intraoperative nerve monitoring; and (IV) surgical strategy may be better defined if a paralysed vocal cord is detected preoperatively. Methods This is a review of studies of patients who underwent routine preoperative laryngoscopy to anticipate preoperative VCP and that evaluated related risk factors, including previous surgery, voice function complaints, and a diagnosis of malignancy. The estimated risk of sustaining preoperative VCF in the absence of these factors was determined. The relevant current guidelines from different professional bodies are also addressed. Results The level of evidence that supports routine preoperative laryngoscopy is weak. The risk of harboring preoperative VCP in the absence of previous neck or other risk-related surgery, advanced malignancy or voice symptoms is very low (0.5% of cases). Conclusions Selective rather than routine use of preoperative laryngoscopy may be acceptable provided that the risk of undetected paralysis is as low as can be reasonably ascertained from the available literature. PMID:25713775

  6. Using 3D printed models for planning and guidance during endovascular intervention: a technical advance

    PubMed Central

    Itagaki, Michael W.

    2015-01-01

    Three-dimensional (3D) printing applications in medicine have been limited due to high cost and technical difficulty of creating 3D printed objects. It is not known whether patient-specific, hollow, small-caliber vascular models can be manufactured with 3D printing, and used for small vessel endoluminal testing of devices. Manufacture of anatomically accurate, patient-specific, small-caliber arterial models was attempted using data from a patient’s CT scan, free open-source software, and low-cost Internet 3D printing services. Prior to endovascular treatment of a patient with multiple splenic artery aneurysms, a 3D printed model was used preoperatively to test catheter equipment and practice the procedure. A second model was used intraoperatively as a reference. Full-scale plastic models were successfully produced. Testing determined the optimal puncture site for catheter positioning. A guide catheter, base catheter, and microcatheter combination selected during testing was used intraoperatively with success, and the need for repeat angiograms to optimize image orientation was minimized. A difficult and unconventional procedure was successful in treating the aneurysms while preserving splenic function. We conclude that creation of small-caliber vascular models with 3D printing is possible. Free software and low-cost printing services make creation of these models affordable and practical. Models are useful in preoperative planning and intraoperative guidance. PMID:26027767

  7. Using 3D printed models for planning and guidance during endovascular intervention: a technical advance.

    PubMed

    Itagaki, Michael W

    2015-01-01

    Three-dimensional (3D) printing applications in medicine have been limited due to high cost and technical difficulty of creating 3D printed objects. It is not known whether patient-specific, hollow, small-caliber vascular models can be manufactured with 3D printing, and used for small vessel endoluminal testing of devices. Manufacture of anatomically accurate, patient-specific, small-caliber arterial models was attempted using data from a patient's CT scan, free open-source software, and low-cost Internet 3D printing services. Prior to endovascular treatment of a patient with multiple splenic artery aneurysms, a 3D printed model was used preoperatively to test catheter equipment and practice the procedure. A second model was used intraoperatively as a reference. Full-scale plastic models were successfully produced. Testing determined the optimal puncture site for catheter positioning. A guide catheter, base catheter, and microcatheter combination selected during testing was used intraoperatively with success, and the need for repeat angiograms to optimize image orientation was minimized. A difficult and unconventional procedure was successful in treating the aneurysms while preserving splenic function. We conclude that creation of small-caliber vascular models with 3D printing is possible. Free software and low-cost printing services make creation of these models affordable and practical. Models are useful in preoperative planning and intraoperative guidance. PMID:26027767

  8. Preoperative weight gain might increase risk of gastric bypass surgery

    PubMed Central

    Istfan, Nawfal W.; Anderson, Wendy A.; Apovian, Caroline M.; Hess, Donald T.; Forse, Armour R.

    2014-01-01

    Background Weight loss improves the cardiovascular and metabolic risk associated with obesity. However, insufficient data are available about the health effects of weight gain, separate from the obesity itself. We sought to determine whether the changes in body weight before open gastric bypass surgery (OGB) would have a significant effect on the immediate perioperative hospital course. Methods A retrospective chart review of 100 consecutive patients was performed to examine the effects of co-morbidities and body weight changes in the immediate preoperative period on the hospital length of stay and the rate of admission to the surgical intensive care unit (SICU). Results Of our class III obese patients undergoing OGB, 95% had ≥1 co-morbid condition and an overall SICU admission rate of 18%. Compared with the patients with no perioperative SICU admission, the patients admitted to the SICU had a greater degree of insulin resistance (homeostatic model analysis–insulin resistance 10.8 ± 1.3 versus 5.9 ± 0.5, P = .001), greater serum triglyceride levels (225 ± 47 versus 143 ± 8 mg/dL, P = .003), and had gained more weight preoperatively (.52 ± .13 versus .06 ± .06 lb/wk, P = .003). The multivariate analyses showed that preoperative weight gain was a risk factor for a longer length of stay and more SICU admissions lasting ≥3 days, as were a diagnosis of sleep apnea and an elevated serum triglyceride concentration. Conclusion The results of the present retrospective study suggest that weight gain increases the risk of perioperative SICU admission associated with OGB, independent of the body mass index. Sleep apnea and elevated serum triglyceride levels were also important determinants of perioperative morbidity. In view of the increasing epidemic of obesity and the popularity of bariatric surgical procedures, we propose that additional clinical and metabolic research focusing on the understanding of the complex relationship among obesity, positive energy

  9. Preoperative patient assessment: Identifying patients at high risk.

    PubMed

    Boehm, O; Baumgarten, G; Hoeft, A

    2016-06-01

    Postoperative mortality remains alarmingly high with a mortality rate ranging between 0.4% and 4%. A small subgroup of multimorbid and/or elderly patients undergoing different surgical procedures naturally confers the highest risk of complications and perioperative death. Therefore, preoperative assessment should identify these high-risk patients and stratify them to individualized monitoring and treatment throughout all phases of perioperative care. A "tailored" perioperative approach might help further reduce perioperative morbidity and mortality. This article aims to elucidate individual morbidity-specific risks. It further suggests approaches to detect patients at the risk of perioperative complications. PMID:27396802

  10. The effect of preoperative warming on patients' postoperative temperatures.

    PubMed

    Cooper, Shauna

    2006-05-01

    Many perioperative clinicians encounter difficulty in preventing hypothermia in surgical patients. One intervention to prevent perioperative hypothermia is the use of forced-air warming. Although forced-air warming is used most frequently in the intraoperative area, prewarming patients with forced-air warming systems before induction of anesthesia may be enough to prevent hypothermia throughout the surgical procedure, allowing patients to arrive in the postanesthesia care unit in a normothermic state. A review of the literature on preoperative forced-air warming is provided, and the effect of prewarming on postoperative patient temperatures is discussed. PMID:16722285

  11. Rhinoplasty: clinical categorization as a practical preoperative guide.

    PubMed

    Thomas, J R; McKinney, J

    1985-12-01

    As progressively more individuals desire rhinoplasty, facial surgeons are experiencing a wider spectrum of potential patients. The young woman in her late teens and 20s once made up the majority of the rhinoplasty case load. Now, the patients desiring aesthetic and reconstructive nasal surgery represent all stages of life. We have divided the patient population into five categories based principally on the special requirements of inherent chronologic differences. This typing system guides rhinoplastic surgeons in dealing with a variety of age groups of both sexes. These categories are useful in defining differences in technique and as an adjunct to preoperative evaluation. PMID:4071177

  12. Current techniques in preoperative imaging for abdomen-based perforator flap microsurgical breast reconstruction.

    PubMed

    Mathes, David W; Neligan, Peter C

    2010-01-01

    Perforator-based microsurgical reconstruction of the breast has steadily increased since the introduction of the technique in the 1990s. The procedure appears to offer less postoperative pain, lower abdominal morbidity, and better preservation of the rectus muscles than the more conventional flaps. However, the major disadvantage of these flaps that they can be difficult to harvest, resulting in a longer operative times. The challenges in flap dissection are a result of the variability in the vascular anatomy of the deep inferior epigastric artery (DIEA) and its perforating branches through the rectus muscle. The location, number, and caliber of the perforators and the intramuscular trajectory of the DIEA branches vary greatly not only from individual to individual, but from one hemiabdomen to the other. The establishment of a presurgical map of the vessels on the abdomen facilitates surgical planning and may decrease operating room time, reduce intraoperative complications, and possibly improve outcomes. This article reviews the available techniques for preoperative planning with the currently available imaging modalities of handheld Doppler, color Doppler (duplex) ultrasound, computed tomography angiography, and magnetic resonance angiography. PMID:20024888

  13. Breast Cancer Preoperative Staging: Does Contrast-Enhanced Magnetic Resonance Mammography Modify Surgery?

    PubMed Central

    Perono Biacchiardi, Chiara; Brizzi, Davide; Genta, Franco; Zanon, Eugenio; Camanni, Marco; Deltetto, Francesco

    2011-01-01

    Women with newly diagnosed breast cancer may have lesions undetected by conventional imaging. Recently contrast-enhanced magnetic resonance mammography (CE-MRM) showed higher sensitivity in breast lesions detection. The present analysis was aimed at evaluating the benefit of preoperative CE-MRM in the surgical planning. From 2005 to 2009, 525 consecutive women (25–75 years) with breast cancer, newly diagnosed by mammography, ultrasound, and needle-biopsy, underwent CE-MRM. The median invasive tumour size was 19 mm. In 144 patients, CE-MRM identified additional lesions. After secondlook, 119 patients underwent additional biopsy. CE-MRM altered surgery in 118 patients: 57 received double lumpectomy or wider excision (41 beneficial), 41 required mastectomy (40 beneficial), and 20 underwent contra lateral surgery (18 beneficial). The overall false-positive rate was 27.1% (39/144). CE-MRM contributed significantly to the management of breast cancer, suggesting more extensive disease in 144/525 (27.4%) patients and changing the surgical plan in 118/525 (22.5%) patients (99/525, 18.8% beneficial). PMID:22295233

  14. Effects of 4 weeks preoperative exercise on knee extensor strength after anterior cruciate ligament reconstruction

    PubMed Central

    Kim, Do Kyung; Hwang, Ji Hye; Park, Won Hah

    2015-01-01

    [Purpose] After an anterior cruciate ligament injury and subsequent reconstruction, quadriceps muscle weakness and disruption of proprioceptive function are common. The purpose of this study was to examine the effects of a 4 weeks preoperative exercise intervention on knee strength power and function post-surgery. [Subjects and Methods] Eighty male patients (27.8±5.7 age), scheduled for reconstruction surgery, were randomly assigned to two groups, the preoperative exercise group (n=40) and a no preoperative exercise group (n=40). The preoperative exercise group participated in a 4-week preoperative and 12-week post-operative programs, while the no preoperative exercise group participated only in the 12-week postoperative exercise program. Isokinetic measured of quadriceps strength were obtained at 4 weeks before and 3 months after surgery. [Results] The knee extensor strength deficits measured at 60°/s and 180°/s was significantly lower in the preoperative exercise group compared with the no preoperative exercise group. At 3 months after surgery, the extensor strength deficit was 28.5±9.0% at 60°/sec and 23.3±9.0% at 180°/sec in the preoperative exercise group, whereas the no preoperative exercise group showed extensor strength deficits of 36.5±10.7% and 27.9±12.6% at 60°/sec and 180°/sec, respectively. The preoperative exercise group demonstrated significant improvement the single-leg hop distance. [Conclusion] Four week preoperative exercise may produce many positive effects post reconstruction surgery, including faster recovery of knee extensor strength and function, as measured by single-leg hop ability. PMID:26504270

  15. Obstructive Sleep Apnea: Preoperative Screening and Postoperative Care.

    PubMed

    Wolfe, Robert M; Pomerantz, Jonathan; Miller, Deborah E; Weiss-Coleman, Rebecca; Solomonides, Tony

    2016-01-01

    The incidence of obstructive sleep apnea (OSA) has reached epidemic proportions, and it is an often unrecognized cause of perioperative morbidity and mortality. Profound hypoxic injury from apnea during the postoperative period is often misdiagnosed as cardiac arrest due to other causes. Almost a quarter of patients entering a hospital for elective surgery have OSA, and >80% of these cases are undiagnosed at the time of surgery. The perioperative period puts patients at high risk of apneic episodes because of drug effects from sedatives, narcotics, and general anesthesia, as well as from the effects of postoperative rapid eye movement sleep changes and postoperative positioning in the hospital bed. For adults, preoperative screening using the STOP or STOP-Bang questionnaires can help to identify adult patients at increased risk of OSA. In the pediatric setting, a question about snoring should be part of every preoperative examination. For patients with known OSA, continuous positive airway pressure should be continued postoperatively. Continuous pulse oximetry monitoring with an alarm system can help to prevent apneic catastrophes caused by OSA in the postoperative period. PMID:26957384

  16. Current status of preoperative drainage for distal biliary obstruction.

    PubMed

    Sugiyama, Harutoshi; Tsuyuguchi, Toshio; Sakai, Yuji; Mikata, Rintaro; Yasui, Shin; Watanabe, Yuto; Sakamoto, Dai; Nakamura, Masato; Sasaki, Reina; Senoo, Jun-Ichi; Kusakabe, Yuko; Hayashi, Masahiro; Yokosuka, Osamu

    2015-08-28

    Preoperative biliary drainage (PBD) was developed to improve obstructive jaundice, which affects a number of organs and physiological mechanisms in patients waiting for surgery. However, its role in patients who will undergo pancreaticoduodenectomy for biliary obstruction remains controversial. This article aims to review the current status of the use of preoperative drainage for distal biliary obstruction. Relevant articles published from 1980 to 2015 were identified by searching MEDLINE and PubMed using the keywords "PBD", "pancreaticoduodenectomy", and "obstructive jaundice". Additional papers were identified by a manual search of the references from key articles. Current studies have demonstrated that PBD should not be routinely performed because of the postoperative complications. PBD should only be considered in carefully selected patients, particularly in cases where surgery had to be delayed. PBD may be needed in patients with severe jaundice, concomitant cholangitis, or severe malnutrition. The optimal method of biliary drainage has yet to be confirmed. PBD should be performed by endoscopic routes rather than by percutaneous routes to avoid metastatic tumor seeding. Endoscopic stenting or nasobiliary drainage can be selected. Although more expensive, the use of metallic stents remains a viable option to achieve effective drainage without cholangitis and reintervention. PMID:26328029

  17. Preoperative Prediction of Aortic Insufficiency During Ventricular Assist Device Treatment.

    PubMed

    Imamura, Teruhiko; Kinugawa, Koichiro

    2016-01-01

    Survival rate in patients with stage D heart failure has improved significantly owing to the development of continuous flow left ventricular assist devices (LVAD), but aortic insufficiency (AI) still remains one of the major unsolved complications that impairs patient quality of life. There are no established treatments for AI, and preoperative prediction and prevention of AI is needed. The opening of a native aortic valve (AV) is a sufficient condition for prevention of AI, and improvement of LV ejection fraction due to LV reverse remodeling (LVRR) is essential to open a native AV. Preoperative insufficient β-blocker treatment and pulsatile flow LVAD usage are keys for LVRR, opening of an AV, and prevention of AI. The second mechanism that leads to AI is remodeling of the aortic root and degeneration of a native AV, which results from reduced pulse pressure during LVAD support. Centrifugal or pulsatile flow LVAD usage has an advantage in terms of preserving pulsatility, and may prevent AI compared with an axial pump. There is less probability of avoiding AI with sufficient β-blocker treatment, and these patients may be good candidates for concomitant surgical intervention to a native AV at the time of LVAD implantation. PMID:26742702

  18. Motion of the kidney between preoperative and intraoperative positioning.

    PubMed

    Schneider, Caitlin; Nguan, Christopher; Longpre, Michelle; Rohling, Robert; Salcudean, Septimiu

    2013-06-01

    For many laparoscopic surgical procedures, the preoperative images are taken with the patient in a different position than that in which the surgery is performed. The organ shift between positions can affect surgical image guidance, as the organ shifts can complicate image registration. In particular, for partial nephrectomy, the standard clinical approach requires supine preoperative computed tomography, while the surgery is performed in the flank position. We studied ten subjects in both supine and flank positions. Rigid registration was used to determine the relative motion of the kidneys, using the spine as a pose-independent landmark. Our results showed that the kidney can move as much as 46.5 mm as a result of a supine-to-flank change in patient position, and rotate as much as 25°. From the results, significant kidney motion occurs due to the change of patient position from supine to flank. These changes warrant further study to understand and model the patient specific motion. PMID:23322758

  19. Preoperative prediction of reversible myocardial asynergy by postexercise radionuclide ventriculography

    SciTech Connect

    Rozanski, A.; Berman, D.; Gray, R.; Diamond, G.; Raymond, M.; Prause, J.; Maddahi, J.; Swan, H.J.; Matloff, J.

    1982-07-22

    Myocardial asynergy is sometimes reversed by coronary bypass, and a noninvasive method of predicting which assess are reversible would be desirable. To assess whether changes in myocardial wall motion observed immediately after exercise can differentiate reversible from nonreversible myocardial asynergy, we evaluated 53 patients by radionuclide ventriculography before and after exercise and again at rest after coronary bypass surgery. Preoperative improvement in wall motion immediately after exercise was highly predictive of the surgical outcome (average chance-corrected agreement, 91 per cent). At surgery the asynergic segments that had improved after exercise were free of grossly apparent epicardial scarring. The accuracy of these predictions for postoperative improvement was significantly greater (P less than 0.01) than that of analysis of Q waves on resting electrocardiography (average chance-corrected agreement, 40 per cent). In contrast, preoperative changes in left ventricular ejection fraction after exercise were not predictive of postoperative resting ejection fraction. We conclude that postexercise radionuclide ventriculography can be used to identify reversible resting myocardial asynergy. This test should prove effective in predicting which patients with myocardial asynergy are most likely to benefit from aortocoronary revascularization.

  20. Preoperative Embolization of Extra-axial Hypervascular Tumors with Onyx

    PubMed Central

    Fusco, Matthew R.; Salem, Mohamed M.; Reddy, Arra S.; Ogilvy, Christopher S.; Kasper, Ekkehard M.; Thomas, Ajith J.

    2016-01-01

    Objective Preoperative endovascular embolization of intracranial tumors is performed to mitigate anticipated intraoperative blood loss. Although the usage of a wide array of embolic agents, particularly polyvinyl alcohol (PVA), has been described for a variety of tumors, literature detailing the efficacy, safety and complication rates for the usage of Onyx is relatively sparse. Materials and Methods We reviewed our single institutional experience with pre-surgical Onyx embolization of extra-axial tumors to evaluate its efficacy and safety and highlight nuances of individualized cases. Results Five patients underwent pre-surgical Onyx embolization of large or giant extra-axial tumors within 24 hours of surgical resection. Four patients harbored falcine or convexity meningiomas (grade I in 2 patients, grade II in 1 patient and grade III in one patient), and one patient had a grade II hemangiopericytoma. Embolization proceeded uneventfully in all cases and there were no complications. Conclusion This series augments the expanding literature confirming the safety and efficacy of Onyx in the preoperative embolization of extra-axial tumors, underscoring its advantage of being able to attain extensive devascularization via only one supplying pedicle. PMID:27114961

  1. Current status of preoperative drainage for distal biliary obstruction

    PubMed Central

    Sugiyama, Harutoshi; Tsuyuguchi, Toshio; Sakai, Yuji; Mikata, Rintaro; Yasui, Shin; Watanabe, Yuto; Sakamoto, Dai; Nakamura, Masato; Sasaki, Reina; Senoo, Jun-ichi; Kusakabe, Yuko; Hayashi, Masahiro; Yokosuka, Osamu

    2015-01-01

    Preoperative biliary drainage (PBD) was developed to improve obstructive jaundice, which affects a number of organs and physiological mechanisms in patients waiting for surgery. However, its role in patients who will undergo pancreaticoduodenectomy for biliary obstruction remains controversial. This article aims to review the current status of the use of preoperative drainage for distal biliary obstruction. Relevant articles published from 1980 to 2015 were identified by searching MEDLINE and PubMed using the keywords “PBD”, “pancreaticoduodenectomy”, and “obstructive jaundice”. Additional papers were identified by a manual search of the references from key articles. Current studies have demonstrated that PBD should not be routinely performed because of the postoperative complications. PBD should only be considered in carefully selected patients, particularly in cases where surgery had to be delayed. PBD may be needed in patients with severe jaundice, concomitant cholangitis, or severe malnutrition. The optimal method of biliary drainage has yet to be confirmed. PBD should be performed by endoscopic routes rather than by percutaneous routes to avoid metastatic tumor seeding. Endoscopic stenting or nasobiliary drainage can be selected. Although more expensive, the use of metallic stents remains a viable option to achieve effective drainage without cholangitis and reintervention. PMID:26328029

  2. [Preoperative management to reduce morbidity and mortality of hip fracture].

    PubMed

    Ferré, F; Minville, V

    2011-10-01

    Hip femur is extremely common in the elderly and is one of the most common reasons for admission in trauma care. The main reported causes of death after hip fracture were cardiovascular (29%), neurological (20%) and pulmonary. Large epidemiological studies have shown a relatively small decrease in mortality for 20 years despite an active approach to medical and surgical management. Yet 57% of deaths occurring within 30 days post-surgery are preventable because they are not related to a pre-existing disease. Preoperative management to optimize these patients could help to reduce morbidity and mortality and is thus a crucial issue. The anesthesia consultation is used to evaluate the perioperative risk, treat pain, manage treatment and stabilize the patient. An operative delay of more than 48hours after admission increases mortality. This period should not be prolonged by unnecessary investigations that will not change the perioperative management. The preoperative period is a key moment because it allows to choose the anesthetic technique. Even if this choice is controversial, continuous spinal anesthesia (titrated) do not modify the cardiovascular and neurological physiological balance of these precarious patients. PMID:21945704

  3. Essential elements of the preoperative breast reconstruction evaluation

    PubMed Central

    Cheng, Angela

    2015-01-01

    A plethora of options exist for breast reconstruction and preoperative evaluation must be thorough to lead to a successful outcome. We review multiple components of the preoperative assessment including the patient’s history, goals, imaging, and key elements of the physical exam. Consideration for tumor biology, staging, need or response to chemotherapy or radiation therapy is important in deciding on immediate versus delayed reconstruction. It is also important to consider the patient’s anatomy, breast size and whether the reconstruction will be unilateral or bilateral. The reconstructive surgeon must accommodate all these factors to consider partial or complete mastectomy defects and guide the patient to the most appropriate reconstructive technique whether it be an oncoplastic reduction mammoplasty, expander-based reconstruction, immediate implant reconstruction, or immediate versus delayed autologous tissue reconstruction such as the deep inferior epigastric artery perforator (DIEP)/transverse rectus abdominis muscle (TRAM), latissimus, transverse upper gracilis (TUG)/profunda femoris artery perforator (PAP), or gluteal artery perforator (GAP) flaps. PMID:26005641

  4. Association of Preoperative Biliary Drainage with Postoperative Morbidity after Pancreaticoduodenectomy

    PubMed Central

    Liu, Chang; Lu, Jian-Wen; Du, Zhao-Qing; Liu, Xue-Min; Lv, Yi; Zhang, Xu-Feng

    2015-01-01

    Background. The advantages or disadvantages of preoperative biliary drainage (PBD) prior to pancreaticoduodenectomy (PD) remain unclear. Methods. A prospectively maintained database was queried for 335 consecutive patients undergoing standard PD surgery between 2009 and 2013. Clinical data and postoperative complications of the 47 patients receiving PBD and 288 patients with early surgery were compared. A matching analysis was also performed between patients receiving or not receiving PBD (no-PBD). Results. The indication for PBD was severe obstructive jaundice (81%) and cholangitis (26%) at the time of PBD. 47 PBD patients had higher bilirubin level than 288 no-PBD patients preoperatively (363.2 μmol/L versus 136.0 μmol/L, p < 0.001). Although no significant difference of any complications could be observed between the two groups, positive intraoperative bile culture and wound infection seemed to be moderately increased in PBD compared to no-PBD patients (p = 0.084 and 0.183, resp.). In the matched-pair comparison, the incidence of wound infection was three times higher in PBD than no-PBD patients (14.9% versus 4.3%, p = 0.080). Conclusions. PBD seems to moderately increase the risk of postoperative wound and bile duct infection. Therefore, PBD should be selectively performed prior to PD. PMID:26798333

  5. Preoperative Uterine Artery Embolization (PUAE) Before Uterine Fibroid Myomectomy

    SciTech Connect

    Dumousset, E.; Chabrot, P.; Rabischong, B.; Mazet, N.; Nasser, S.; Darcha, C.; Garcier, J.M.; Mage, G.; Boyer, L.

    2008-05-15

    Purpose. To evaluate the potential of uterine artery embolization to minimize blood loss and facilitate easier removal of fibroids during subsequent myomectomy. Methods. This retrospective study included 22 patients (median age 37 years), of whom at least 15 wished to preserve their fertility. They presented with at least one fibroid (mean diameter 85.6 mm) and had undergone preoperative uterine artery embolization (PUAE) with resorbable gelatin sponge. Results. No complication or technical failure of embolization was identified. Myomectomies were performed during laparoscopy (12 cases) and laparotomy (9 cases). One hysterectomy was performed. The following were noted: easier dissection of fibroids (mean 5.6 per patient, range 1-30); mean intervention time 113 min (range 25-210 min); almost bloodless surgery, with a mean peroperative blood loss of 90 ml (range 0-806 ml); mean hemoglobin pretherapeutically 12.3 g/dl (range 5.9-15.2 g/dl) and post-therapeutically 10.3 g/dl (range 5.6-13.3 g/dl), with no blood transfusion needed. Patients were discharged on day 4 on average and the mean sick leave was 1 month. Conclusion. Preoperative embolization is associated with minimal intraoperative blood loss. It does not increase the complication rate or impair operative dissection, and improves the chances of performing conservative surgery.

  6. Preoperative thrombocytosis predicts prognosis in stage II colorectal cancer patients

    PubMed Central

    Lee, Yong Sun; Suh, Kwang Wook

    2016-01-01

    Purpose Thrombocytosis is known to be a poor prognostic factor in several types of solid tumors. The prognostic role of preoperative thrombocytosis in colorectal cancer remains limited. The aim of this study is to investigate the prognostic role of preoperative thrombocytosis in stage II colorectal cancer. Methods Two hundred eighty-four patients with stage II colorectal cancer who underwent surgical resection between December 2003 and December 2009 were retrospectively reviewed. Thrombocytosis was defined as platelet > 450 × 109/L. We compared patients with thrombocytosis and those without thrombocytosis in terms of survival. Results The 5-year disease-free survival (DFS) rates were lower in patients with thrombocytosis compared to those without thrombocytosis in stage II colorectal cancer (73.3% vs. 89.6%, P = 0.021). Cox multivariate analysis demonstrated that thrombocytosis (hazard ratio, 2.945; 95% confidence interval, 1.127–7.697; P = 0.028) was independently associated with DFS in patients with stage II colorectal cancer. Conclusion This study showed that thrombocytosis is a prognostic factor predicting DFS in stage II colorectal cancer patients. PMID:27274508

  7. Histological differences between preoperative chemoradiotherapy and chemotherapy for rectal cancer: a clinicopathological study.

    PubMed

    Sakuyama, Naoki; Kojima, Motohiro; Kawano, Shingo; Akimoto, Tetsuo; Saito, Norio; Ito, Masaaki; Ochiai, Atsushi

    2016-05-01

    Pathological studies on the different histological effects between neoadjuvant chemotherapy (NAC) and preoperative chemoradiation therapy (preoperative CRT) have not been performed. The purpose of this study is to elucidate the histological differences in tissue received from NAC and preoperative CRT for rectal cancer to evaluate whether a pathological assessment method used after CRT can be applied for NAC. One hundred and thirty-eight patients were enrolled in this study; 88 patients underwent their operations after preoperative CRT or NAC, and 50 patients underwent surgery only. Residual tumor area was measured using morphometry software and we compared the stromal component of myofibroblasts, immune cells, and vasculature to elucidate the difference of therapeutic effect between them. The grade of reduction after preoperative CRT was more prominent than that seen in NAC. Also, ypT downstaging was more prominent in preoperative CRT than in NAC, and ypN downstaging was more frequent in NAC than in preoperative CRT. Preoperative CRT showed more marked myofibroblasts and fewer immune cells than did NAC, which indicates different effects on the cancer microenvironment. Our histological results suggest different effects between NAC and preoperative CRT on tumor tissue. The best assessment method available for a variable therapeutic protocol should be further investigated. PMID:27112135

  8. Prognostic value of preoperative inflammatory response biomarkers in patients with sarcomatoid renal cell carcinoma and the establishment of a nomogram

    PubMed Central

    Gu, Liangyou; Ma, Xin; Li, Hongzhao; Chen, Luyao; Xie, Yongpeng; Zhao, Chaofei; Luo, Guoxiong; Zhang, Xu

    2016-01-01

    To examine the prognostic role of inflammatory response biomarkers in sarcomatoid renal cell carcinoma (sRCC). From January 2004 to May 2015, 103 patients with sRCC were enrolled in this study. Preoperative neutrophil to lymphocyte ratio (NLR), derived neutrophil to lymphocyte ratio (dNLR), platelet to lymphocyte ratio (PLR) and lymphocyte to monocyte ratio (LMR) were analyzed. Besides well-established clinicopathological prognostic factors, we evaluated the prognostic value of this four markers using Kaplan-Meier method and Cox regression models. Additionally, a nomogram was established to predict the prognosis of sRCC patients. Elevated NLR, dNLR and PLR were significantly associated with worse overall survival (OS), nevertheless, elevated LMR showed an adverse effect on reduced OS. Multivariate analysis revealed that NLR (HR = 4.07, 95% CI = 1.50–11.00, P = 0.006) retained as independent factor. Incorporation of the NLR into a prognostic model including T stage, M stage, tumor necrosis and percentage of sarcomatoid generated a nomogram, which accurately predicted OS for sRCC patients. Preoperative NLR may serve as a potential prognostic biomarker in patients with sRCC and may help with clinical decisions about treatment intervention in clinical practice. The proposed nomogram can be used for the prediction of OS in patients with sRCC. PMID:27035802

  9. Preoperative Scintigrams to Identify the Sentinel Lymph Node in Breast Cancer: a Waste of Time?

    PubMed

    Sharma, N; Pinto, A; Notghi, A; Sintler, M

    2015-12-01

    Sentinel lymph node biopsy (SLNB) remains the gold standard for assessing axillary node status in breast cancer. Preoperative scintigrams have been used to identify the sentinel lymph node (SLN); however, their use is controversial. Studies suggest they add little to successful SLN detection in theatre, immediately prior to node excision. They have been associated with high false negatives, time expense, patient dissatisfaction, and unnecessary costs. The aim of the present study was to evaluate the diagnostic accuracy of scintigrams in comparison to intraoperative SLN identification techniques. This study included all patients undergoing a SLNB for breast cancer from April 2010 to 2011. Scintigram reports, operation notes, and histology results were analyzed. Mann-Whitney U and chi-squared tests were used for statistical analysis of data. Two hundred nineteen female patients with a median age of 59.6 years (24.0-89.9 years) were included in this study. Scintigram was performed in 185 and not in 34 patients due to time constraints. Combined γ-probe and Isosulfan blue dye for SLN detection (intraoperative methods) have an identification rate of 98.2 % (p = 0.005), compared to 92.4 % (p = 0.088) from scintigrams alone. Scintigrams confer no additional advantage to the operating surgeon for successful SLN detection and excision in theatre. Intraoperative SLN identification is more accurate and reliable. Routine scintigram use is unjustified and should be withdrawn from current practice. PMID:27011606

  10. Sensitivity and specificity of stroboscopy in preoperative differentiation of dysplasia from early invasive glottic carcinoma.

    PubMed

    El-Demerdash, A; Fawaz, S A; Sabri, S M; Sweed, Ahmed; Rabie, H

    2015-05-01

    Leukoplakia is a descriptive clinical term designating a white patch or plaque of the mucosa and must be complemented by histology, which can range from simple totally benign keratosis with or without atypia up to invasive carcinoma. The aim of this study is to evaluate the accuracy of videostroboscopy in preoperative differentiation of early invasive glottic carcinoma from intraepithelial atypia and dysplasia. 46 patients with a total of 60 leukoplakia lesions on the vocal folds were included in the study. Videostroboscopy was used to divide them into two groups based on preservation of the mucosal wave and this was correlated with the final pathology after treatment. The sensitivity and specificity of videostroboscopy in predicting invasive nature of the lesions based on absence or reduction of the mucosal wave were 96.8 and 92.8 %, respectively, with an overall accuracy of 95 %. We suggest that routine application of videostroboscopy can be an important, simple, non-invasive tool, to achieve, in a single procedure, proper and accurate evaluation of glottic leukoplakia. PMID:25649284

  11. Analysis of Preoperative Detection for Apex Prostate Cancer by Transrectal Biopsy

    PubMed Central

    Sazuka, Tomokazu; Imamoto, Takashi; Namekawa, Takeshi; Utsumi, Takanobu; Yanagisawa, Mitsuru; Kawamura, Koji; Kamiya, Naoto; Suzuki, Hiroyoshi; Ueda, Takeshi; Ota, Satoshi; Nakatani, Yukio; Ichikawa, Tomohiko

    2013-01-01

    Background. The aim of this study was to determine concordance rates for prostatectomy specimens and transrectal needle biopsy samples in various areas of the prostate in order to assess diagnostic accuracy of the transrectal biopsy approach, especially for presurgical detection of cancer in the prostatic apex. Materials and Methods. From 2006 to 2011, 158 patients whose radical prostatectomy specimens had been evaluated were retrospectively enrolled in this study. Concordance rates for histopathology results of prostatectomy specimens and needle biopsy samples were evaluated in 8 prostatic sections (apex, middle, base, and transitional zones bilaterally) from 73 patients diagnosed at this institution, besides factors for detecting apex cancer in total 118 true positive and false negative apex cancers. Results. Prostate cancer was found most frequently (85%) in the apex of all patients. Of 584 histopathology sections, 153 (49%) from all areas were false negatives, as were 45% of apex biopsy samples. No readily available preoperative factors for detecting apex cancer were identified. Conclusions. In Japanese patients, the most frequent location of prostate cancer is in the apex. There is a high false negative rate for transrectal biopsy samples. To improve the detection rate, transperitoneal biopsy or more accurate imaging technology is needed. PMID:23533779

  12. Incorporating a Gaussian model at the catheter tip for improved registration of preoperative surface models

    NASA Astrophysics Data System (ADS)

    Rettmann, M. E.; Holmes, D. R., III; Packer, D. L.; Robb, R. A.

    2011-03-01

    Atrial fibrillation is a common cardiac arrhythmia in which aberrant electrical activity cause the atria to quiver which results in irregular beating of the heart. Catheter ablation therapy is becoming increasingly popular in treating atrial fibrillation, a procedure in which an electrophysiologist guides a catheter into the left atrium and creates radiofrequency lesions to stop the arrhythmia. Typical visualization tools include bi-plane fluoroscopy, 2-D ultrasound, and electroanatomic maps, however, recently there has been increased interest in incorporating preoperative surface models into the procedure. Typical strategies for registration include landmark-based and surface-based methods. Drawbacks of these approaches include difficulty in accurately locating corresponding landmark pairs and the time required to sample surface points with a catheter. In this paper, we describe a new approach which models the catheter tip as a Gaussian kernel and eliminates the need to collect surface points by instead using the stream of continuosly tracked catheter points. We demonstrate the feasibility of this technique with a left atrial phantom model and compare the results with a standard surface based approach.

  13. Saturation biopsy improves preoperative Gleason scoring of prostate cancer.

    PubMed

    Kahl, Philip; Wolf, Susanne; Adam, Alexander; Heukamp, Lukas Carl; Ellinger, Jörg; Vorreuther, Roland; Solleder, Gerold; Buettner, Reinhard

    2009-01-01

    We evaluated the differences between conventional needle biopsy (CB) and saturation biopsy (SB) techniques with regard to the prediction of Gleason score, tumor stage, and insignificant prostate cancer. Data from a total number of 240 patients were analyzed. The main group, consisting of 185 patients, was diagnosed according to a saturation prostate needle biopsy protocol (SB), by which more than 12 cores were taken per biopsy. The control group was diagnosed using CB, by which 12 or less than 12 cores were taken per biopsy (n=55). In the main group, the Gleason score of the biopsy was confirmed in 19.5%, in the control group in 23.5% according to the prostatectomy specimen (p=0.50). Upgrading after the operation was found in 56.7% in the main group and in 60% in the control group (p=0.24). Downgrading after the operation was found in 23.9% in the main group and in 16.3% in the control group (p=0.24). If the Gleason score of the postoperative specimens differed by only one point from the biopsy, we considered this a minor deviation. In the main group, 59% of the carcinomas were preoperatively classified correctly or revealed minor deviation in Gleason scores. In contrast, only 47% of the carcinomas in the control group were assessed correctly or with minor deviation in Gleason scores. Thus, the main group demonstrated a better rate of preoperative prediction in tumor grading assessed by Gleason score (p=0.05). In addition, the Gleason scores of both protocols were assigned to three groups (Gleason <7; Gleason 7; Gleason >7), and the group changes from the biopsy to the prostatectomy specimen were found to be significantly more frequent in the CB group (p=0.04). There was no significant difference between the two types of biopsy techniques regarding tumor stage or the detection of insignificant carcinomas. The advantage of the extensive prostate needle biopsy technique (SB) is a better preoperative prediction of the Gleason score as well as the risk groups with

  14. Relevance of Imaging Examinations in the Surgical Planning of Patients with Bowel Endometriosis

    PubMed Central

    Trippia, Carlos H.; Zomer, Monica T.; Terazaki, Carlos R.T.; Martin, Rafael L.S.; Ribeiro, Reitan; Kondo, William

    2016-01-01

    Endometriosis is a benign gynecologic disease characterized by the presence of endometrial tissue outside the uterine cavity. The complexity of the disease results from its multiple clinical presentations, the multifocal pattern of distribution of the lesions, the presence of extra pelvic sites of the disease (mainly affecting the urinary and the intestinal tracts), and the difficulty in the preoperative diagnosis (by means of imaging studies) and in the surgical treatment. The preoperative mapping of the lesions, either by ultrasound or by magnetic resonance imaging, allows for an adequate surgical planning and a better preoperative patient counseling, especially in those women with deep infiltrating endometriosis affecting the bowel. Also, the choice of the surgical team that is going to perform the procedure may be based on the preoperative workup. In this paper, we highlight the important findings that should be described in the imaging examination reports for the preoperative workup of patients with deep infiltrating endometriosis of the intestine. PMID:26917983

  15. Relevance of Imaging Examinations in the Surgical Planning of Patients with Bowel Endometriosis.

    PubMed

    Trippia, Carlos H; Zomer, Monica T; Terazaki, Carlos R T; Martin, Rafael L S; Ribeiro, Reitan; Kondo, William

    2016-01-01

    Endometriosis is a benign gynecologic disease characterized by the presence of endometrial tissue outside the uterine cavity. The complexity of the disease results from its multiple clinical presentations, the multifocal pattern of distribution of the lesions, the presence of extra pelvic sites of the disease (mainly affecting the urinary and the intestinal tracts), and the difficulty in the preoperative diagnosis (by means of imaging studies) and in the surgical treatment. The preoperative mapping of the lesions, either by ultrasound or by magnetic resonance imaging, allows for an adequate surgical planning and a better preoperative patient counseling, especially in those women with deep infiltrating endometriosis affecting the bowel. Also, the choice of the surgical team that is going to perform the procedure may be based on the preoperative workup. In this paper, we highlight the important findings that should be described in the imaging examination reports for the preoperative workup of patients with deep infiltrating endometriosis of the intestine. PMID:26917983

  16. CT staging and preoperative assessment of resectability for thymic epithelial tumors

    PubMed Central

    Shen, Yan; Gu, Zhitao; Ye, Jianding; Mao, Teng; Chen, Wenhu

    2016-01-01

    Background The aim of this study was to determine the computed tomography (CT) features potentially helpful for accurate staging and predicting resectability of thymic epithelial tumors (TET). Methods One hundred and thirty-eight consecutive TET patients undergoing surgical resection from April 2010 to November 2011 were prospectively entered into a database. All patients were staged according to the Masaoka-Koga staging system. The relationship between CT features with tumor staging and complete resection was reviewed after surgery. Results Surgico-pathological staging was stage I in 63, stage II in 32, stage III in 32, and stage IV in 11 patients. Preoperative CT staging was highly consistent with postoperative surgico-pathological staging (Kappa =0.525). Tumor shape, contour, enhancement, with or without invasion of the adjacent structures (mediastinal fat, mediastinal pleura, lung, pericardium, mediastinal vessels, phrenic nerve), and presence of pleural, pericardial effusionor intrapulmonary metastasis were correlated with Masaoka-Koga staging (P<0.05). However, tumor size, internal density or presence of calcification was not associated with staging (P>0.05). Tumor size, presence of calcification and mediastinal lymph node enlargement were not correlated with complete tumor resection (P>0.05). Tumor shape, contour, internal density, enhancement pattern, and invasion of adjacent structures were related to complete resection of the primary tumor in univariate analysis (P<0.05). However, upon multivariate logistic regression, only absence of artery systems invasion was predictive of complete resection (P<0.05). Conclusions Clinical staging of TET could be accurately evaluated with CT features including tumor shape, contour, enhancement pattern, with or without invasion of adjacent structures, and presence of pleural, pericardial effusion or intrapulmonary metastasis. Absence of arterial system invasion on CT was the only predictive feature for predicting

  17. Preoperative induction therapy for locally advanced thymic tumors: a retrospective analysis using the ChART database

    PubMed Central

    Wei, Yucheng; Gu, Zhitao; Fu, Jianhua; Tan, Liejie; Zhang, Peng; Han, Yongtao; Chen, Chun; Zhang, Renquan; Li, Yin; Chen, Keneng; Chen, Hezhong; Liu, Yongyu; Cui, Youbing; Wang, Yun; Pang, Liewen; Yu, Zhentao; Zhou, Xinming; Liu, Yangchun; Liu, Yuan

    2016-01-01

    Background To evaluate the role of preoperative induction therapy on prognosis of locally advanced thymic malignancies. Methods Between 1994 and 2012, patients received preoperative induction therapies (IT group) in the Chinese Alliance for Research in Thymomas (ChART) database, were compared with those having surgery directly after preoperative evaluation (DS group). All tumors receiving induction therapies were locally advanced (clinically stage III–IV) before treatment and those turned out to be in pathological stage I and II were considered downstaged by induction. Clinical pathological characteristics were retrospectively analyzed. To more accurately study the effect of induction therapies, stage IV patients were then excluded. Only stage I-III tumors in the IT group and stage III cases in the DS group were selected for further comparison in a subgroup analysis. Results Only 68 (4%) out of 1,713 patients had induction therapies, with a R0 resection of 67.6%, 5-year recurrence of 44.9%, and 5- and 10-year overall survivals (OS) of 49.7% and 19.9%. Seventeen patients (25%) were downstaged after induction. Significantly more thymomas were downstaged than thymic carcinomas (38.7% vs. 13.9%, P=0.02). Tumors downstaged after induction had significantly higher 5-year OS than those not downstaged (93.8% vs. 35.6%, P=0.013). For the subgroup analysis when stage IV patients were excluded, 5-year OS was 85.2% in the DS group and 68.1% in the IT group (P=0.000), although R0 resection were similar (76.4% vs. 73.3%, P=0.63). However, 5-year OS in tumors downstaged after induction (93.8%) was similar to those in the DS group (85.2%, P=0.438), both significantly higher than those not downstaged after induction (35.6%, P=0.000). Conclusions Preoperative neoadjuvant therapy have been used only occasionally in locally advanced thymic malignances. Effective induction therapy leading to tumor downstaging may be beneficial for potentially unresectable diseases, especially in

  18. Preoperative Chemoradiation With Cetuximab, Irinotecan, and Capecitabine in Patients With Locally Advanced Resectable Rectal Cancer: A Multicenter Phase II Study

    SciTech Connect

    Kim, Sun Young; Hong, Yong Sang; Kim, Dae Yong; Kim, Tae Won; Kim, Jee Hyun; Im, Seok Ah; Lee, Keun Seok; Yun, Tak; Jeong, Seung-Yong; Choi, Hyo Seong; Lim, Seok-Byung; Chang, Hee Jin; Jung, Kyung Hae

    2011-11-01

    Purpose: To evaluate the efficacy and safety of preoperative chemoradiation with cetuximab, irinotecan, and capecitabine in patients with rectal cancer. Methods and Materials: Forty patients with locally advanced, nonmetastatic, and mid- to lower rectal cancer were enrolled. Radiotherapy was delivered at a dose of 50.4 Gy/28 fractions. Concurrent chemotherapy consisted of an initial dose of cetuximab of 400 mg/m{sup 2} 1 week before radiotherapy, and then cetuximab 250 mg/m{sup 2}/week, irinotecan 40 mg/m{sup 2}/week for 5 consecutive weeks and capecitabine 1,650 mg/m{sup 2}/day for 5 days a week (weekdays only) from the first day during radiotherapy. Total mesorectal excision was performed within 6 {+-} 2 weeks. The pathologic responses and survival outcomes were evaluated as study endpoints, and an additional KRAS mutation analysis was performed. Results: In total, 39 patients completed their planned preoperative chemoradiation and underwent R0 resection. The pathologic complete response rate was 23.1% (9/39), and 3 patients (7.7%) showed near total regression of tumor. The 3-year disease-free and overall survival rates were 80.0% and 94.7%, respectively. Grade 3/4 toxicities included leukopenia (4, 10.3%), neutropenia (2, 5.1%), anemia (1, 2.6%), diarrhea (2, 5.1%), fatigue (1, 2.6%), skin rash (1, 2.6%), and ileus (1, 2.6%). KRAS mutations were found in 5 (13.2%) of 38 patients who had available tissue for testing. Clinical outcomes were not significantly correlated with KRAS mutation status. Conclusions: Preoperative chemoradiation with cetuximab, irinotecan, and capecitabine was active and well tolerated. KRAS mutation status was not a predictive factor for pathologic response in this study.

  19. Preoperational test report, primary ventilation condenser cooling system

    SciTech Connect

    Clifton, F.T.

    1997-10-29

    This represents the preoperational test report for the Primary Ventilation Condenser Cooling System, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system uses a closed chilled water piping loop to provide offgas effluent cooling for tanks AY101, AY102, AZ1O1, AZ102; the offgas is cooled from a nominal 100 F to 40 F. Resulting condensation removes tritiated vapor from the exhaust stack stream. The piping system includes a package outdoor air-cooled water chiller with parallel redundant circulating pumps; the condenser coil is located inside a shielded ventilation equipment cell. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

  20. Preoperative Localization and Surgical Margins in Conservative Breast Surgery

    PubMed Central

    Corsi, F.; Sorrentino, L.; Bossi, D.; Sartani, A.; Foschi, D.

    2013-01-01

    Breast-conserving surgery (BCS) is the treatment of choice for early breast cancer. The adequacy of surgical margins (SM) is a crucial issue for adjusting the volume of excision and for avoiding local recurrences, although the precise definition of an adequate margins width remains controversial. Moreover, other factors such as the biological behaviour of the tumor and subsequent proper systemic therapies may influence the local recurrence rate (LRR). However, a successful BCS requires preoperative localization techniques or margin assessment techniques. Carbon marking, wire-guided, biopsy clips, radio-guided, ultrasound-guided, frozen section analysis, imprint cytology, and cavity shave margins are commonly used, but from the literature review, no single technique proved to be better among the various ones. Thus, an association of two or more methods could result in a decrease in rates of involved margins. Each institute should adopt its most congenial techniques, based on the senologic equipe experience, skills, and technologies. PMID:23986868

  1. Effectiveness of preoperative analgesics on postoperative dental pain: a study.

    PubMed Central

    Zacharias, M.; Hunter, K. M.; Baker, A. B.

    1996-01-01

    Patients undergoing extractions of third molar teeth under general anesthesia were given a placebo, diclofenac (a nonsteroidal anti-inflammatory drug) 100 mg, or methadone (an opiate) 10 mg 60 to 90 min prior to surgery, and their pain scores and postoperative medication requirements were measured for 3 days. All patients received local anesthetic blocks and analgesic drugs during the perioperative period. There were no significant differences between the three groups in the pain scores and medication requirements during the period of study. It was concluded that preoperative use of nonsteroidal anti-inflammatory drugs and opiates may not offer a preemptive analgesic effect in patients who have had adequate analgesia during the surgery. Continued use of analgesic drugs during the postoperative period is perhaps more useful for this purpose. There appears to be a higher incidence of vomiting following opiates (methadone), precluding its clinical use in day-care patients. PMID:10323113

  2. Different preoperative approaches for acute lumber spinal fractures

    PubMed Central

    Tian, Lu-Feng; Yuan, Yan-Sheng; Li, En-Hui; Wang, Lei

    2015-01-01

    To compare the long and short term effectiveness of different preoperative approaches for lumber spinal fractures and finds a better surgical method for the disease. Follow up records of 144 patients received hyperbaric oxygen therapy or methylprednisolone infusion within 8 hours after the lubmer spinal injury were analyzed. Postoperative outcome immediately and 3, 6, 12, 36 months after the surgery were compared to evaluate the effectiveness two different approaches. The results indicated that there are no significant differences regarding age, sexual proportion, body mass index (BMI), visual analogue scale of pain (VAS) score as well as Frankel scores before the surgery, and significant differences VAS score as well as Frankel scores immediately after the surgery. In conclusion, hyperbaric oxygen therapy within 8 hours after the injury can be more effective than methylprednisolone infusion in patients with lumber spinal injury. PMID:26309686

  3. Klatskin tumor: Diagnosis, preoperative evaluation and surgical considerations.

    PubMed

    Molina, Víctor; Sampson, Jaime; Ferrer, Joana; Sanchez-Cabus, Santiago; Calatayud, David; Pavel, Mihai Calin; Fondevila, Constantino; Fuster, Jose; García-Valdecasas, Juan Carlos

    2015-11-01

    Hiliar cholangiocarcinoma is the most common type of cholangiocarcinoma, an represent around 10% of all hepatobiliary tumors. It is an aggressive malignancy, resectable in around 47% of the patients at diagnosis. Complete resection is the most effective and only potentially curative therapy, with a survival rate of less than 12 months in unresectable cases. Axial computerized tomography and magnetic resonance are the most useful image techniques to determine the surgical resectability. Clinically, jaundice and pruritus are the most common symptoms at diagnosis;preoperative biliary drainage is recommended using endoscopic retrograde cholangiography or percutaneous transhepatic cholangiography. Surgery using extended liver resections with an en bloc resection of the liver with vascular reconstruction is the technique with the highest survival. Complete resection with histologically negative resection margins (R0), nodal involvement and metastases are the most important prognostic factors. PMID:26298684

  4. [Evaluation of a preoperative virtual tour for parents and children].

    PubMed

    Tourigny, Jocelyne; Chartrand, Julie

    2009-03-01

    A Canadian pediatric center has set a preoperative virtual tour on its website. This tour was evaluated by a descriptive study, in terms of utilization, efficacy and usefulness. The tour was utilized by 49.6% of the 123 families. Children of these families had a significant increase in knowledge from Time I (preop clinic) to Time 2 (day of surgery). Children and youth who did not use the tour reported themselves as more anxious the day of surgery but not significantly. There was no significant change in parents. The internet is a useful tool in families' preparation but cannot replace a direct interaction. Other researches are necessary in order to evaluate the impact of this type of preparation on the quality of care and on the child's recovery. PMID:19388414

  5. [Preoperative evaluation and perioperative prevention of infectious diseases].

    PubMed

    Moriyama, Kiyoshi

    2010-09-01

    Preoperative evaluation of infectious diseases in patients for elective and non-elective surgery is important for the anesthesiologists not only to rule out the patient's state of illness, but also to prevent transmission of infectious diseases in healthcare settings. To prevent transmission of infectious diseases in healthcare settings, Center for Disease Control published guidelines that consist of standard precaution and transmission-based precautions. In the face of exposure to known infectious diseases, certain post exposure prophylaxis has been established, especially against exposure to human immunodeficiency virus and hepatitis B virus. There are also growing interests in perioperative prevention of surgical site infection, since World Health Organization has published surgical safety checklist with the slogan "Safe surgery saves life". Anesthesiologists need to have knowledge on the prevention of surgical site infection especially on antibiotic prophylaxis, because it starts in the operating room. PMID:20857671

  6. Ultrasound in preoperative evaluation for dialysis-access placement.

    PubMed

    Wilson, Nicole A; Shenoy, Surendra

    2014-01-01

    US vessel mapping for vascular access creation has evolved as standard practice in the preoperative evaluation of an ESRD patient. The best yield from this technology is when it is used to compliment physical examination and viewed in realtime by the operating physician. It is important to evaluate both arterial and venous systems during vessel mapping. While minimum diameters have been associated with an increased chance of maturation of an AV access, the quality of the vessel wall also plays an important role in maturation. US has a distinct advantage of being a noninvasive modality that can evaluate both structural and functional aspects of vessels that play an important role in access maturation. PMID:25040792

  7. An Overview of Preoperative Glucose Evaluation, Management, and Perioperative Impact

    PubMed Central

    Sheehy, Ann M.; Gabbay, Robert A.

    2009-01-01

    Perioperative hyperglycemia is a common phenomenon affecting patients both with and without a known prior history of diabetes. Despite an exponential rise in publications and studies of inpatient hyperglycemia over the last decade, many questions still exist as to what defines optimal care of these patients. Initial enthusiasm for tight glycemic control has waned as the unanticipated reality of hypoglycemia and mortality has been realized in some prospective studies. The recent dramatic modification of national practice guidelines to endorse more modest inpatient glycemic targets highlights the dynamic nature of current knowledge as the next decade approaches. This review discusses perioperative hyperglycemia and the categories of patients affected by it. It reviews current recommendations for ambulatory diabetes screening and its importance in preoperative patient care. Finally, it concludes with a review of current practice guidelines, as well as a discussion of future direction and goals for inpatient perioperative glycemic control. PMID:20144379

  8. Preoperative intensity modulated radiation therapy for retroperitoneal sarcoma.

    PubMed

    El-Bared, Nancy; Taussky, Daniel; Mehiri, Selma; Patocskai, Erika; Roberge, David; Donath, David

    2014-06-01

    The use of intensity modulated radiation therapy (IMRT) has allowed for the administration of high doses to retroperitoneal sarcomas (RSTS) while limiting toxicity to adjacent organs. The purpose of our study is to assess the outcome and toxicities of patients with RSTS treated with neo-adjuvant external beam radiation (EBRT) therapy using IMRT. This is a retrospective study of 21 patients treated with preoperative IMRT for primary or recurrent RSTS between 2005 and 2011. Overall survival (OS) and local recurrence free survival (LRFS) were computed using the Kaplan-Meier method (log-rank test). Acute and chronic toxicities were assessed using the CTCAE v. 3 criteria. The actuarial 2 and 3-year OS was 66% for both and the 5-year OS was 51%. As for LRFS it was 57% at 2 and 3-year and 51% for the 5-year LRFS. Factors predictive for local control were microscopically negative margins (p = 0.022), a median tumor diameter <15 cm (p = 0.007) and pathology of liposarcoma (p = 0.021). Furthermore, patients treated for recurrent disease fared worse (p = 0.04) in local control than patients treated for primary disease. As for OS, patients treated for Grade 1 histology had a better outcome (p 5 0.05). EBRT was generally well tolerated. Acute gastrointestinal (GI) Grade 1 or 2 toxicities occurred in 33% of patients and one patient had unexplained post-radiation Grade 2 fever that resolved after tumor resection. As for chronic toxicities 24% of our patients presented Grade 1 GI toxicity and one patient presented Grade 3 small bowel stenosis not clearly due to radiation toxicity. Despite the location and volume of the tumors treated, preoperative IMRT was very well tolerated in our patients with retroperitoneal sarcoma. Unfortunately local recurrences remain common and dose escalation is to be considered. PMID:23919397

  9. Preoperative infusional chemoradiation therapy for stage T3 rectal cancer

    SciTech Connect

    Rich, T.A.; Skibber, J.M.; Ajani, J.A.

    1995-07-15

    To evaluate preoperative infusional chemoradiation for patients with operable rectal cancer. Preoperative chemoradiation therapy using infusional 5-fluorouracil (5-FU), (300 mg/m{sup 2}/day) together with daily irradiation (45 Gy/25 fractions/5 weeks) was administered to 77 patients with clinically Stage T3 rectal cancer. Endoscopic ultrasound confirmed the digital rectal exam in 63 patients. Surgery was performed approximately 6 weeks after the completion of chemoradiation therapy and included 25 abdominoperineal resections and 52 anal-sphincter-preserving procedures. Posttreatment tumor stages were T1-2, N0 in 35%, T3, N0 in 25%, and T1-3, N1 in 11%; 29% had no evidence of tumor. Local tumor control after chemoradiation was seen in 96% (74 out of 77); 2 patients had recurrent disease at the anastomosis site and were treated successfully with abdominoperineal resection. Overall, pelvic control was obtained in 99% (76 out of 77). The survival after chemoradiation was higher in patients without node involvement than in those having node involvement (p = n.s.). More patients with pathologic complete responses or only microscopic foci survived than did patients who had gross residual tumor (p = 0.07). The actuarial survival rate was 83% at 3 years; the median follow-up was 27 months, with a range of 3 to 68 months. Acute, perioperative, and late complications were not more numerous or more severe with chemoradiation therapy than with traditional radiation therapy (XRT) alone. Excellent treatment response allowed two-thirds of the patients to have an anal-sphincter-sparing procedure. Gross residual disease in the resected specimen indicates a poor prognosis, and therapies specifically targeting these patients may improve survival further. 22 refs., 2 figs., 3 tabs.

  10. Preoperative Intensity Modulated Radiation Therapy for Retroperitoneal Sarcoma

    PubMed Central

    El-Bared, Nancy; Taussky, Daniel; Mehiri, Selma; Patocskai, Erika; Roberge, David; Donath, David

    2014-01-01

    The use of intensity modulated radiation therapy (IMRT) has allowed for the administration of high doses to retroperitoneal sarcomas (RSTS) while limiting toxicity to adjacent organs. The purpose of our study is to assess the outcome and toxicities of patients with RSTS treated with neo-adjuvant external beam radiation (EBRT) therapy using IMRT. This is a retrospective study of 21 patients treated with preoperative IMRT for primary or recurrent RSTS between 2005 and 2011. Overall survival (OS) and local recurrence free survival (LRFS) were computed using the Kaplan-Meier method (log-rank test). Acute and chronic toxicities were assessed using the CTCAE v. 3 criteria. The actuarial 2 and 3-year OS was 66% for both and the 5-year OS was 51%. As for LRFS it was 57% at 2 and 3-year and 51% for the 5-year LRFS. Factors predictive for local control were microscopically negative margins (p = 0.022), a median tumor diameter <5 cm (p = 0.007) and pathology of liposarcoma (p = 0.021). Furthermore, patients treated for recurrent disease fared worse (p = 0.04) in local control than patients treated for primary disease. As for OS, patients treated for Grade 1 histology had a better outcome (p = 0.05). EBRT was generally well tolerated. Acute gastrointestinal (GI) Grade 1 or 2 toxicities occurred in 33% of patients and one patient had unexplained post-radiation Grade 2 fever that resolved after tumor resection. As for chronic toxicities 24% of our patients presented Grade 1 GI toxicity and one patient presented Grade 3 small bowel stenosis not clearly due to radiation toxicity. Despite the location and volume of the tumors treated, preoperative IMRT was very well tolerated in our patients with retroperitoneal sarcoma. Unfortunately local recurrences remain common and dose escalation is to be considered. PMID:23919397

  11. [Subjective verbal methods in preoperative measurement of anxiety].

    PubMed

    Höfling, S; Hutner, G; Ott, H; Fichte, K; Doenicke, A

    1988-06-01

    The role of preoperative anxiety in perioperative adaptation is viewed in two different ways. Janis suggested that anxiety is a drive that evokes the cognitive work of worrying. Leventhal stresses the importance of coping behavior for adaptation, while anxiety may or may not accompany this coping process. Both theories have empirical support. The aim of this study was to determine whether both theories could show empirical support because the scientists chose different methods: Janis used interviews, Leventhal and Lazarus anxiety scales. The study analyzed the pre- and postoperative emotional reactions of surgical patients with three different methods of anxiety measurement: an anxiety scale, a fear thermometer, and a psychoanalytic interview (Gottschalk-Gleser content analysis method). The different methods were compared and related to the adaptation behavior (Table 3). The data showed a clear interaction between the selected methods and respective theories about the effects of preoperative anxiety on intra- and postoperative adaptation. The anxiety scales showed no correlation with adaptation behavior (blood pressure and heart rate during surgery; postoperative pain medication) and were not related to the anxiety scores obtained from the interview (content analysis). On the other hand, the interview anxiety measurements showed a clear relationship between separation anxiety (and also shame anxiety), physiological excitement during surgery (increase in heart rate), and postoperative medication (increased analgesics and tranquilizers). The patients who worried about the risks of surgery (Verletzungsangst, see Fig. 3) had very good perioperative adjustment, so that the quality of anxiety measured in the interview was very important for the prediction of adaptation. PMID:3407901

  12. Effects of Preoperative Clarithromycin Administration in Patients with Nasal Polyposis

    PubMed Central

    Perić, A; Baletić, N; Milojević, M; Sotirović, J; Živić, L; Perić, AV; Vojvodić, D

    2014-01-01

    ABSTRACT Objective: In recent years, various investigators have shown considerable interest in the use of macrolide antibiotics for treatment of chronic rhinosinusitis and nasal polyposis. The aim of this study was to evaluate the clinical effects of preoperative long-term, low-dose clarithromycin administration in patients with nasal polyposis. Methods: Eighty nasal polyp patients (42 non-atopic and 38 atopic) were included in this prospective, non-placebo controlled investigation and randomized equally to either the combined clarithromycin-surgical or surgical group. Forty patients received 500 mg of clarithromycin daily for eight weeks, and, after evaluation, they were treated by functional endoscopic sinus surgery (FESS). The other 40 patients were treated only surgically. The nasal symptom scores and endoscopic scores after macrolide treatment/surgical treatment, and after six and 12 months of follow-up were evaluated. Results: After clarithromycin therapy, we found improvement in symptom scores in 25/40, and improvement in endoscopic scores in 19/40 patients. We found no significant difference in nasal symptom score between allergic and non-allergic patients regarding the outcome to macrolide (p = 0.352) or surgical treatment (p = 0.396). When we compared differences between endoscopic scores at the time points of 12 months and six months postoperatively (ESt12 minus ESt6), we found statistically lower differences in the clarithromycin-surgery group than in the surgery group (p = 0.006). Conclusion: Preoperative clarithromycin administration postponed nasal polyp relapse after FESS. Allergies have no influence on the clinical efficacy of clarithromycin therapy and on the efficacy of FESS. PMID:25867579

  13. Pre-operational environmental monitoring plan for the Device Assembly Facility at the Nevada Test Site

    SciTech Connect

    Ferate, F.D.

    1995-01-01

    Nuclear explosives operations have been and may continue to be an important component of the DOE mission at the NTS. This mission has been to conduct the nation`s nuclear testing program in a safe, secure, and efficient manner while assuring full compliance with state and federal regulations, and DOE order`s and directives. These operations have generally included assembly, disassembly or modification, staging, transportation, and tesbng of nuclear explosive devices. They may also include maintenance, repair, retrofit, and surveillance. The Device Assembly Facility (DAF) was constructed to provide a dedicated facility in which to prepare nuclear explosives assemblies for their intended disposition. This facility will provide for combined operations (replacing two separate facilities) and incorporates state-of-the-art safety and security features while minimizing the risks of environmental impacts. The facility has been completed but not yet operated, so the impacts to be considered will b e based on normal operations and not on the impacts of construction activities. The impacts will arise from nuclear explosives operations that require the handling of high explosives in combination with special nuclear materials. Wastes from operation of the earlier device assembly facilities have included grams of epoxies, pints of solvents, and small quantities of waste explosives. These are hazardous (includes radioactive) wastes and are disposed of in accordance with state and federal regulations. Assuming similar operations at the DAF, non-hazardous (includes non-radioactive) solid waste would be transported to a permitted landfill. Waste explosives would be sent to the Area 11 Explosive Ordnance Disposal Unit. Other hazardous waste would be sent to the Area 5 Radioactive Waste.Management Site for shipment or burial.

  14. Factors Associated with Preoperative Magnetic Resonance Imaging Use among Medicare Beneficiaries with Nonmetastatic Breast Cancer.

    PubMed

    Henderson, Louise M; Weiss, Julie; Hubbard, Rebecca A; O'Donoghue, Cristina; DeMartini, Wendy B; Buist, Diana S M; Kerlikowske, Karla; Goodrich, Martha; Virnig, Beth; Tosteson, Anna N A; Lehman, Constance D; Onega, Tracy

    2016-01-01

    Preoperative breast magnetic resonance imaging (MRI) use among Medicare beneficiaries with breast cancer has substantially increased from 2005 to 2009. We sought to identify factors associated with preoperative breast MRI use among women diagnosed with ductal carcinoma in situ (DCIS) or stage I-III invasive breast cancer (IBC). Using Surveillance, Epidemiology, and End Results and Medicare data from 2005 to 2009 we identified women ages 66 and older with DCIS or stage I-III IBC who underwent breast-conserving surgery or mastectomy. We compared preoperative breast MRI use by patient, tumor and hospital characteristics stratified by DCIS and IBC using multivariable logistic regression. From 2005 to 2009, preoperative breast MRI use increased from 5.9% to 22.4% of women diagnosed with DCIS and 7.0% to 24.3% of women diagnosed with IBC. Preoperative breast MRI use was more common among women who were younger, married, lived in higher median income zip codes and had no comorbidities. Among women with IBC, those with lobular disease, smaller tumors (<1 cm) and those with estrogen receptor negative tumors were more likely to receive preoperative breast MRI. Women with DCIS were more likely to receive preoperative MRI if tumors were larger (>2 cm). The likelihood of receiving preoperative breast MRI is similar for women diagnosed with DCIS and IBC. Use of MRI is more common in women with IBC for tumors that are lobular and smaller while for DCIS MRI is used for evaluation of larger lesions. PMID:26511204

  15. Metabolomic analysis of percutaneous fine-needle aspiration specimens of thyroid nodules: Potential application for the preoperative diagnosis of thyroid cancer

    PubMed Central

    Ryoo, Inseon; Kwon, Hyuknam; Kim, Soo Chin; Jung, Seung Chai; Yeom, Jeong A; Shin, Hwa Seon; Cho, Hye Rim; Yun, Tae Jin; Choi, Seung Hong; Sohn, Chul-Ho; Park, Sunghyouk; Kim, Ji-hoon

    2016-01-01

    Thyroid nodules are a very common problem. Since malignant thyroid nodules should be treated surgically, preoperative diagnosis of thyroid cancer is very crucial. Cytopathologic analysis of percutaneous fine-needle aspiration (FNA) specimens is the current gold standard for diagnosing thyroid nodules. However, this method has led to high rates of inconclusive results. Metabolomics has emerged as a useful tool in medical fields and shown great potential in diagnosing various cancers. Here, we evaluated the potential of nuclear magnetic resonance (NMR) analysis of percutaneous FNA specimens for preoperative diagnosis of thyroid cancer. We analyzed metabolome of FNA samples of papillary thyroid carcinoma (n = 35) and benign follicular nodule (n = 69) using a proton NMR spectrometer. The metabolomic profiles showed a considerable discrimination between benign and malignant nodules. Receiver operating characteristic (ROC) curve analysis indicated that seven metabolites could serve as discriminators (area under ROC curve value, 0.64–0.85). These findings demonstrated that NMR analysis of percutaneous FNA specimens of thyroid nodules can be potentially useful in the accurate and rapid preoperative diagnosis of thyroid cancer. PMID:27440433

  16. Does preoperative psychological status of patients affect postoperative pain? A prospective study from the Caribbean

    PubMed Central

    Bradshaw, Prisca; Hariharan, Seetharaman; Chen, Deryk

    2016-01-01

    Objectives: Patients with high anxiety states in the preoperative period often have more intense postoperative pain, despite adequate pain control during the intraoperative period. This study aimed to determine the relationship between the preoperative psychological status and the pain experienced postoperatively in a sample of Caribbean patients. Design and methods: A prospective study was conducted in elective surgical adult patients at a teaching hospital in the Caribbean. Patients’ preoperative psychological status was assessed using Hospital Anxiety and Depression Scale (HADS), and a preoperative ‘expected’ pain score was recorded. Postoperatively, ‘observed’ pain scores at 4 and 24 hours and the maximum pain score during 24 hours were recorded. Demographic data and clinical details including data regarding postoperative analgesia were collected. Expected and observed pain scores were compared between patients with and without anxiety and depression. Results: A total of 304 patients were enrolled. The overall prevalence of anxiety and depression was 43% and 27%, respectively, based on the HADS scores. There were significant associations between the postoperative pain scores and factors such as preoperative anxiety and depression (HADS) scores, preoperative expected pain scores, patient educational level, presence of preoperative pain and surgical duration. Age, gender, ethnicity and type of anaesthesia did not impact postoperative pain scores. Conclusion: The presence of preoperative anxiety and depression as indicated by HADS score may significantly influence postoperative pain. Other factors such as educational level, presence of preoperative pain and surgical duration may also impact postoperative pain. Some of these factors may be modifiable and must be addressed in the preoperative period. PMID:27551421

  17. Is preoperative physical activity related to post-surgery recovery? A cohort study of patients with breast cancer

    PubMed Central

    Nilsson, Hanna; Angerås, Ulf; Bock, David; Börjesson, Mats; Onerup, Aron; Fagevik Olsen, Monika; Gellerstedt, Martin; Haglind, Eva; Angenete, Eva

    2016-01-01

    Objective The aim of our study is to assess the association between preoperative level of activity and recovery after breast cancer surgery measured as hospital stay, length of sick leave and self-assessed physical and mental recovery. Design A prospective cohort study. Setting Patients included were those scheduled to undergo breast cancer surgery, between February and November 2013, at two participating hospitals in the Western Region of Sweden. Participants Patients planned for breast cancer surgery filled out a questionnaire before, as well as at 3 and 6 weeks after the operation. The preoperative level of activity was self-assessed and categorised into four categories by the participants using the 4-level Saltin-Grimby Physical Activity Level Scale (SGPALS). Main outcome measure Our main outcome was postoperative recovery measured as length of sick leave, in-hospital stay and self-assessed physical and mental recovery. Results 220 patients were included. Preoperatively, 14% (31/220) of participants assessed themselves to be physically inactive, 61% (135/220) to exert some light physical activity (PA) and 20% (43/220) to be more active (level 3+4). Patients operated with mastectomy versus partial mastectomy and axillary lymph node dissection versus sentinel node biopsy were less likely to have a short hospital stay, relative risk (RR) 0.88 (0.78 to 1.00) and 0.82 (0.70 to 0.96). More active participants (level 3 or 4) had an 85% increased chance of feeling physically recovered at 3 weeks after the operation, RR 1.85 (1.20 to 2.85). No difference was seen after 6 weeks. Conclusions The above study shows that a higher preoperative level of PA is associated with a faster physical recovery as reported by the patients 3 weeks post breast cancer surgery. After 6 weeks, most patients felt physically recovered, diminishing the association above. No difference was seen in length of sick leave or self-assessed mental recovery between inactive or more active

  18. Preoperative study of the surface ECG for the prognosis of atrial fibrillation maze surgery outcome at discharge.

    PubMed

    Hernández, Antonio; Alcaraz, Raúl; Hornero, Fernando; Rieta, José Joaquín

    2014-07-01

    The Cox-maze surgery is an effective procedure for terminating atrial fibrillation (AF) in patients requiring open-heart surgery associated with another heart disease. After the intervention, regardless of the patient's rhythm, all are treated with oral anticoagulants and antiarrhythmic drugs prior to discharge. Furthermore, patients maintaining AF before discharge could also be treated with electrical cardioversion (ECV). In view of this, a preoperative prognosis of the patient's rhythm at discharge would be helpful for optimizing drug therapy planning as well as for advancing ECV therapy. This work analyzes 30 preoperative electrocardiograms (ECGs) from patients suffering from AF in order to predict the Cox-maze surgery outcome at discharge. Two different characteristics of the AF pattern have been studied. On the one hand, the atrial activity (AA) organization, which provides information about the number of propagating wavelets in the atria, was investigated. AA organization has been successfully used in previous studies related to spontaneous reversion of paroxysmal AF and to the outcome of ECV. To assess organization, the dominant atrial frequency (DAF) and sample entropy (SampEn) have been computed. On the other hand, the second characteristic studied was the fibrillatory wave (f-wave) amplitude, which has been demonstrated to be a valuable indicator of the Cox-maze surgery outcome in previous studies. Moreover, this parameter has been obtained through a new methodology, based on computing the f-wave average power (fWP). Finally, all the computed indices were combined in a decision tree in order to improve prediction capability. Results for the DAF yielded a sensitivity (Se), a specificity (Sp) and an accuracy (Acc) of 61.54%, 82.35% and 73.33%, respectively. For SampEn the values were 69.23%, 76.00% and 73.33%, respectively, and for fWP they were 92.31%, 82.35% and 86.67%, respectively. Finally, the decision tree combining the three parameters analyzed

  19. Evaluation of Stress Intensity and Anxiety Level in Preoperative Period of Cardiac Patients

    PubMed Central

    Rosiek, Anna; Kornatowski, Tomasz; Rosiek-Kryszewska, Aleksandra; Leksowski, Łukasz; Leksowski, Krzysztof

    2016-01-01

    Introduction. The stress related to patient's stay in a hospital increases when it is necessary to perform a surgery. Therefore, the study of the phenomenon of stress intensity in hospitalized patients has become an important issue for public health. Material and Method. The study was conducted in University Hospital No. 1 in the cardiosurgery clinic. The study involved 58 patients who were admitted as planned to the hospital. The study used a standardized questionnaire measuring intensity of the stress and also deepened interviews with patients about stress and anxiety felt before the surgery. Results. The greater the patient's anxiety resulting from his state of health, the greater the intensity of stress in the preoperative period. This relationship is linear. The results of the study also made it possible to see intrapersonal factors (pain, illness, and suffering) and extrapersonal factors (anesthesia, surgery, and complications after surgery), which are causes of anxiety before surgery. Conclusion. The research showed high (negative) results of anxiety and stress associated with the disease, surgery, and complications after cardiac surgery. Active involvement in hospitalization elements, such as patient education before surgery, psychological support, and medical care organization taking into account patient's preferences, reduces the impact of stressors. PMID:27042655

  20. Evaluation of Stress Intensity and Anxiety Level in Preoperative Period of Cardiac Patients.

    PubMed

    Rosiek, Anna; Kornatowski, Tomasz; Rosiek-Kryszewska, Aleksandra; Leksowski, Łukasz; Leksowski, Krzysztof

    2016-01-01

    Introduction. The stress related to patient's stay in a hospital increases when it is necessary to perform a surgery. Therefore, the study of the phenomenon of stress intensity in hospitalized patients has become an important issue for public health. Material and Method. The study was conducted in University Hospital No. 1 in the cardiosurgery clinic. The study involved 58 patients who were admitted as planned to the hospital. The study used a standardized questionnaire measuring intensity of the stress and also deepened interviews with patients about stress and anxiety felt before the surgery. Results. The greater the patient's anxiety resulting from his state of health, the greater the intensity of stress in the preoperative period. This relationship is linear. The results of the study also made it possible to see intrapersonal factors (pain, illness, and suffering) and extrapersonal factors (anesthesia, surgery, and complications after surgery), which are causes of anxiety before surgery. Conclusion. The research showed high (negative) results of anxiety and stress associated with the disease, surgery, and complications after cardiac surgery. Active involvement in hospitalization elements, such as patient education before surgery, psychological support, and medical care organization taking into account patient's preferences, reduces the impact of stressors. PMID:27042655

  1. A Phase I Trial of Preoperative Partial Breast Radiotherapy: Patient Selection, Target Delineation, and Dose Delivery

    PubMed Central

    Blitzblau, Rachel C.; Arya, Ritu; Yoo, Sua; Baker, Jay A.; Chang, Zheng; Palta, Manisha; Duffy, Eileen; Horton, Janet K.

    2015-01-01

    Purpose Diffusion of accelerated partial breast irradiation (APBI) into clinical practice is limited by the need for specialized equipment and training. The accessible external beam technique yields unacceptable complication rates, likely due to large post-operative target volumes. We designed a phase I trial evaluating preoperative radiotherapy to the intact tumor utilizing widely available technology. Methods Patients received 15, 18, or 21Gy in a single fraction to the breast tumor plus margin. Magnetic resonance imaging (MRI) was used in conjunction with standard computed tomography (CT)-based planning to identify contrast enhancing tumor. Skin markers and an intra-tumor biopsy marker were utilized for verification during treatment. Results MRI imaging was critical for target delineation as not all breast tumors were reliably identified on CT scan. Breast shape differences were consistently seen between CT and MRI but did not impede image registration or tumor identification. Target volumes were markedly smaller than historical post-operative volumes and normal tissue constraints were easily met. A biopsy marker within the breast proved sufficient for set up localization. Conclusions This single fraction linear-accelerator based ABPI approach can be easily incorporated at most treatment centers. In vivo targeting may improve accuracy and can reduce the dose to normal tissues. PMID:25834942

  2. Contrast-enhanced ultrasound improves accurate identification of appendiceal mucinous adenocarcinoma in an old patient

    PubMed Central

    Shang, Jing; Ruan, Li-tao; Dang, Ying; Wang, Yun-yue; Song, Yan; Lian, Jie

    2016-01-01

    Abstract Background: Adenocarcinoma of appendiceal origin is far rarer than other colorectal carcinomas and its preoperative diagnosis is challenging. To our knowledge, utility of contrast-enhanced ultrasound (CEUS) to diagnose it is much less. Method: A 61-year-old man presented with abdominal pain in the right lower quadrant for 20 days. In order to fulfill an accurately preoperative diagnosis, he received laboratory and imaging tests such as carcinoembryonic antigen (CEA), computer tomography (CT), CEUS and endoscope. Diagnosis and Intervention: He was initially suspected of suffering appendicitis, while his white blood cell count was normal and carcinoembryonic antigen (CEA) in serum was remarkably increased. Both routine ultrasound and computer tomography (CT) examinations supported suppurative appendicitis. The overall data, however, failed to excluded neoplastic pathology thoroughly. Therefore, CEUS was carried out and showed an inhomogeneous enhancement intra the lesion located in the body of the appendix, which made our consideration of neoplasm. The result of the follow-up biopsy guided by endoscope was consistent with appendiceal tumor. The patient received laparoscopic right hemicolectomy. Histopathology confirmed as well differentiated mucinous adenocarcinoma of appendix origin. His postoperative course was uneventful, and he had a regular diet again without any complaint. Result: Serum CEA was remarkably increased (12.00 ng/mL). Both routine ultrasound and CT examinations supported suppurative appendicitis. However, CEUS examination showed an inhomogeneous enhancement intra the lesion located in the body of the appendix, which made our consideration of neoplasm. The follow-up biopsy guided by endoscope and surgical specimens confirmed as well differentiated mucinous adenocarcinoma of appendix origin. Conclusion: Most mucinous adenocarcinoma mimicking appendicitis results in difficult diagnosis preoperatively. Clinician and radiologist should be

  3. Mill profiler machines soft materials accurately

    NASA Technical Reports Server (NTRS)

    Rauschl, J. A.

    1966-01-01

    Mill profiler machines bevels, slots, and grooves in soft materials, such as styrofoam phenolic-filled cores, to any desired thickness. A single operator can accurately control cutting depths in contour or straight line work.

  4. Remote balance weighs accurately amid high radiation

    NASA Technical Reports Server (NTRS)

    Eggenberger, D. N.; Shuck, A. B.

    1969-01-01

    Commercial beam-type balance, modified and outfitted with electronic controls and digital readout, can be remotely controlled for use in high radiation environments. This allows accurate weighing of breeder-reactor fuel pieces when they are radioactively hot.

  5. Planning of vessel grafts for reconstructive surgery in congenital heart diseases

    NASA Astrophysics Data System (ADS)

    Rietdorf, U.; Riesenkampff, E.; Schwarz, T.; Kuehne, T.; Meinzer, H.-P.; Wolf, I.

    2010-02-01

    The Fontan operation is a surgical treatment for patients with severe congenital heart diseases, where a biventricular correction of the heart can't be achieved. In these cases, a uni-ventricular system is established. During the last step of surgery a tunnel segment is placed to connect the inferior caval vein directly with the pulmonary artery, bypassing the right atrium and ventricle. Thus, the existing ventricle works for the body circulation, while the venous blood is passively directed to the pulmonary arteries. Fontan tunnels can be placed intra- and extracardially. The location, length and shape of the tunnel must be planned accurately. Furthermore, if the tunnel is placed extracardially, it must be positioned between other anatomical structures without constraining them. We developed a software system to support planning of the tunnel location, shape, and size, making pre-operative preparation of the tunnel material possible. The system allows for interactive placement and adjustment of the tunnel, affords a three-dimensional visualization of the virtual Fontan tunnel inside the thorax, and provides a quantification of the length, circumferences and diameters of the tunnel segments. The visualization and quantification can be used to plan and prepare the tunnel material for surgery in order to reduce the intra-operative time and to improve the fit of the tunnel patch.

  6. Planning of skull base surgery in the virtual workbench: clinical experiences.

    PubMed

    Kockro, R A; Serra, L; Tsai, Y T; Chan, C; Sitoh, Y Y; Chua, G G; Hern, N; Lee, E; Hoe, L Y; Nowinski, W

    1999-01-01

    Based on the KRDL Virtual Workbench, we present a neurosurgical planning system called VIVIAN (Virtual Intracranial Visualization And Navigation). This VR environment allows for fast and intuitive interaction with three-dimensional multimodal (MRI, MRA, MRV, CT) patient specific data-sets. The user reaches behind a mirror into a 3D workspace where the 3D data is surrounded by interactive virtual tools-racks. Tumors, blood vessels, cranial nerves and surgically relevant parts of the brain are segmented by interactive control of density transfer-functions or by manual outlining and tracing tools. A neurosurgical procedure is planned by using various visualization and measurement tools and the system allows for the simulation of bone drilling and tissue removal. We have planned 16 cases which required tumor surgery at the cranial base. VIVIAN provided an efficient and comprehensive way to understand pre-operatively the complexity of anatomical and pathological relationships. The ideal craniotomy and the extent of the required skull base exposure could be specified accurately. PMID:10538353

  7. Understanding the Code: keeping accurate records.

    PubMed

    Griffith, Richard

    2015-10-01

    In his continuing series looking at the legal and professional implications of the Nursing and Midwifery Council's revised Code of Conduct, Richard Griffith discusses the elements of accurate record keeping under Standard 10 of the Code. This article considers the importance of accurate record keeping for the safety of patients and protection of district nurses. The legal implications of records are explained along with how district nurses should write records to ensure these legal requirements are met. PMID:26418404

  8. Effects of Preoperative Local Estrogen in Postmenopausal Women With Prolapse: A Randomized Trial

    PubMed Central

    Good, Meadow M.; Roshanravan, Shayzreen M.; Shi, Haolin; Schaffer, Joseph I.; Singh, Ravinder J.; Word, R. Ann

    2014-01-01

    Context: Pelvic organ prolapse (POP) increases in prevalence with age; recurrence after surgical repair is common. Objective: The objective of the study was to determine the effects of local estrogen treatment on connective tissue synthesis and breakdown in the vaginal wall of postmenopausal women planning surgical repair of POP. Design: This was a randomized trial. Setting: The study was conducted at an academic tertiary medical center. Patients or Other Participants: Postmenopausal women with a uterus and symptomatic anterior and/or apical prolapse at stage 2 or greater participated in the study. Intervention: Estrogen (Premarin) or placebo cream for 6 weeks preoperatively was the intervention. Main Outcome Measures: Full-thickness anterior apical vaginal wall biopsies were obtained at the time of hysterectomy and analyzed for mucosa and muscularis thickness, connective tissue synthesis, and degradation. Serum levels of estrone and 17β-estradiol were analyzed at baseline and the day of surgery using highly sensitive liquid chromatography-tandem mass spectrometry. Results: Fifteen women per group (n = 30 total) were randomized; 13 per group underwent surgery. Among drug-adherent participants (n = 8 estrogen, n = 13 placebo), epithelial and muscularis thickness was increased 1.8- and 2.7-fold (P = .002 and P =.088, respectively) by estrogen. Collagen types 1α1 and 1α2 mRNA increased 6.0- and 1.8-fold in the vaginal muscularis (P < .05 for both); collagen type Ia protein increased 9-fold in the muscularis (P = .012), whereas collagen III was not changed significantly. MMP-12 (human macrophage elastase) mRNA was suppressed in the vaginal mucosa from estrogen-treated participants (P = .011), and matrix metalloprotease-9 activity was decreased 6-fold in the mucosa and 4-fold in the muscularis (P = .02). Consistent with menopausal norms, serum estrone and 17β-estradiol were low and did not differ among the two groups. Conclusions: Vaginal estrogen application for 6

  9. Intensity modulated radiation-therapy for preoperative posterior abdominal wall irradiation of retroperitoneal liposarcomas

    SciTech Connect

    Bossi, Alberto . E-mail: alberto.bossi@uz.kuleuven.ac.be; De Wever, Ivo; Van Limbergen, Erik; Vanstraelen, Bianca

    2007-01-01

    Purpose: Preoperative external-beam radiation therapy (preop RT) in the management of Retroperitoneal Liposarcomas (RPLS) typically involves the delivery of radiation to the entire tumor mass: yet this may not be necessary. The purpose of this study is to evaluate a new strategy of preop RT for RPLS in which the target volume is limited to the contact area between the tumoral mass and the posterior abdominal wall. Methods and Materials: Between June 2000 and Jan 2005, 18 patients with the diagnosis of RPLS have been treated following a pilot protocol of pre-op RT, 50 Gy in 25 fractions of 2 Gy/day. The Clinical Target Volume (CTV) has been limited to the posterior abdominal wall, region at higher risk for local relapse. A Three-Dimensional conformal (3D-CRT) and an Intensity Modulated (IMRT) plan were generated and compared; toxicity was reported following the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events v3.0. Results: All patients completed the planned treatment and the acute toxicity was tolerable: 2 patients experienced Grade 3 and 1 Grade 2 anorexia while 2 patients developed Grade 2 nausea. IMRT allows a better sparing of the ipsilateral and the contralateral kidney. All tumors were successfully resected without major complications. At a median follow-up of 27 months 2 patients developed a local relapse and 1 lung metastasis. Conclusions: Our strategy of preop RT is feasible and well tolerated: the rate of resectability is not compromised by limiting the preop CTV to the posterior abdominal wall and a better critical-structures sparing is obtained with IMRT.

  10. Prognostic Implication of Preoperative Behavior Changes in Patients with Primary High-Grade Meningiomas

    PubMed Central

    2014-01-01

    High-grade meningiomas are rare extra-axial tumors, frequently causing brain invasion and prominent brain edema. Patients harboring high-grade meningiomas occasionally present with behavior changes. Data about frequency and prognostic importance of preoperative behavior changes in patients with high-grade meningiomas is missing. 86 patients with primary high-grade meningiomas were analyzed. Statistical analysis was performed to determine correlation of preoperative behavior changes with tumor location, preoperative brain edema, tumor cleavability, tumor grade, Ki67 proliferation index, and microscopic brain invasion. Survival analysis was performed. 30 (34.9%) patients presented with preoperative behavior changes. These changes were more frequent with male patients (P = 0.066) and patients older than 55 years (P = 0.018). They correlated with frontal location (P = 0.013), tumor size (P = 0.023), microscopic brain invasion (P = 0.015), and brain edema (P = 0.006). Preoperative behavior changes did not correlate with duration of symptoms, tumor cleavability, tumor malignancy grade, and Ki67 proliferation index. They were not significantly related to overall survival or recurrence-free survival of patients with primary high-grade meningiomas. Preoperative behavior changes are frequent in patients harboring primary high-grade meningiomas. They correlate with tumor size, microscopic brain invasion, and brain edema. Preoperative behavior changes do not predict prognosis in patients with primary high-grade meningiomas. PMID:24578632

  11. Prevalence and factors associated with preoperative anxiety in children aged 5-12 years 1

    PubMed Central

    de Moura, Louise Amália; Dias, Iohanna Maria Guimarães; Pereira, Lilian Varanda

    2016-01-01

    Abstract Objective: to estimate the prevalence and factors associated with preoperative anxiety in children who wait for outpatient surgery. Method: cross-sectional analysis of baseline data of a prospective cohort study that investigates the predictors of postoperative pain in children aged 5-12 years submitted to inguinal and umbilical hernia repair. It was selected 210 children, which were interviewed in the preoperative holding area of a general hospital. Anxiety was evaluated using the modified Yale Preoperative Anxiety Scale (mYPAS). Sociodemographic and clinical variables were analyzed as exposure and anxiety (mYPAS final score>30) as outcome. Logistic regression was used to identify factors associated with preoperative anxiety. Results: forty-two percent (42.0%) of children presented preoperative anxiety (CI95%: 35.7%-48.6%), with mean scores equal to 30.1 (SD=8.4). Factors associated with preoperative anxiety were: age group of 5-6 years (OR=2.28; p=0.007) and socioeconomic status classified as class C (OR=2.39; p=0.016). Conclusion: the evaluation of children who wait for outpatient surgery should be multidimensional and comprise information on age and socioeconomic status, in order to help in the identification and early treatment of preoperative anxiety. PMID:27305179

  12. Clinical significance of preoperative thrombocytosis in patients who underwent radical nephrectomy for nonmetastatic renal cell carcinoma

    PubMed Central

    Choi, Jae Young; Ko, Young Hwii

    2016-01-01

    Purpose The aim of this study was to examine the association of preoperative thrombocytosis with the prognosis of patients with nonmetastatic renal cell carcinoma (RCC). Materials and Methods We conducted a retrospective analysis of 187 patients who underwent a radical nephrectomy for nonmetastatic RCC between July 1997 and June 2009. Thrombocytosis was defined as a platelet count≥400,000 µL, and patients were divided into 2 groups according to presence of preoperative thrombocytosis, and the cancer-specific survival rates and overall survival rates of the 2 groups after radical nephrectomy were compared. Results The mean age of the patients was 56.0±11.7 years and the mean follow-up period was 59.3±42.1 months; there were 20 patients with preoperative thrombocytosis. Thirty patients developed metastases and 9 patients died during the follow-up period. In Kaplan-Meier analysis using a univariate log-rank test, both cancer-specific survival rate (p=0.013) and overall survival rate (p=0.012) showed significant association with preoperative thrombocytosis. Controlling for pathological TNM stage, Fuhrman grade and tumor diameter, the Cox proportional hazards model for cancer-specific survival rates showed that preoperative thrombocytosis was an independent prognostic factor (p=0.025). Conclusions Preoperative thrombocytosis was associated with poorer prognosis in patients with nonmetastatic RCC. Thus, preoperative platelet count may be clinically useful for risk stratification of patients undergoing surgery for nonmetastatic RCC.

  13. Does Preoperative Weight Change Predict Postoperative Weight Loss After Laparoscopic Sleeve Gastrectomy?

    PubMed Central

    Lane, Aaron E.; Mangieri, Christopher W.; Choi, Yong U.; Faler, Byron J.

    2015-01-01

    Background: Some institutions and insurance companies mandate a preoperative weight loss regimen prior to bariatric surgery. Previous studies suggest little to no correlation between preoperative and postoperative weight loss for laparoscopic Roux-en-Y gastric bypass (RNYGB). This study examined the impact of preoperative weight change for patients undergoing laparoscopic sleeve gastrectomy (LSG). Materials and Methods: A retrospective analysis was performed on patients undergoing LSG at the authors' institution from 2010 to 2012. Patients were grouped based on preoperative weight gain or loss. The correlation between preoperative BMI change and postoperative BMI change was studied, as well as length of surgery. Results: Of 141 patients with 1-year follow-up, 72 lost, six maintained, and 64 gained weight preoperatively. Percentage of excess BMI loss at 1 year was not statistically different between those who lost weight and those who gained weight. Percent change in BMI from initial visit to surgery does not correlate with change in BMI at 1 year postoperatively or with length of surgery. Conclusions: Preoperative weight loss is not a reliable predictor of postoperative weight loss or shorter operative time after LSG. Potential patients who otherwise meet indications for LSG should not be denied based on inability to lose weight. PMID:26421248

  14. Specific test and evaluation plan

    SciTech Connect

    Hays, W.H.

    1998-03-20

    The purpose of this Specific Test and Evaluation Plan (STEP) is to provide a detailed written plan for the systematic testing of modifications made to the 241-AX-B Valve Pit by the W-314 Project. The STEP develops the outline for test procedures that verify the system`s performance to the established Project design criteria. The STEP is a lower tier document based on the W-314 Test and Evaluation Plan (TEP). Testing includes Validations and Verifications (e.g., Commercial Grade Item Dedication activities), Factory Acceptance Tests (FATs), installation tests and inspections, Construction Acceptance Tests (CATs), Acceptance Test Procedures (ATPs), Pre-Operational Test Procedures (POTPs), and Operational Test Procedures (OTPs). It should be noted that POTPs are not required for testing of the transfer line addition. The STEP will be utilized in conjunction with the TEP for verification and validation.

  15. Brief report: total knee arthroplasty performed with patient-specific, pre-operative CT-guided navigation.

    PubMed

    Rubin, Lee E; Murgo, Kenneth T

    2013-03-01

    The clinical success and long-term outcomes of total knee arthroplasty (TKA) are dependent not only on the biomaterials within the prosthetic implant, but also on the surgeon's ability to correctly position the implants onto the bone. Intra-operative computer navigation and robotic surgery have emerged as options to increase the accuracy of implant placement and enhance the outcomes of TKA, with mixed clinical results to date. Pre-operative CT-guided, patient-specific navigation is a unique method for planning TKA surgery to achieving consistent implant positioning, especially for patients with retained surgical hardware or unusual bony anatomy. This technology has been used in Rhode Island in a limited series of patients to assess the utility of the technique and represents an interesting advance for both orthopaedic surgeons and their patients. PMID:23641437

  16. Associations between preoperative functional status and functional outcomes of total joint replacement in the Dominican Republic

    PubMed Central

    Collins, Jamie E.; Ghazinouri, Roya; Alcantara, Luis; Thornhill, Thomas S.; Katz, Jeffrey N.

    2013-01-01

    Objective. In developed countries, the functional status scores of patients with poor preoperative scores undergoing total joint replacement (TJR) improve more following TJR than those for patients with better preoperative scores. However, those with better preoperative scores achieve the best postoperative functional outcomes. We determined whether similar associations exist in a developing country. Methods. Dominican patients undergoing total hip or knee replacement completed WOMAC and SF-36 surveys preoperatively and at 12-month follow-up. Patients were stratified into low-, medium- and high-scoring preoperative groups based on their preoperative WOMAC function scores. We examined the associations between the baseline functional status of these groups and two outcomes—improvement in functional status over 12 months and functional status at 12 months—using analysis of variance with multivariable linear regression. Results. Patients who scored the lowest preoperatively made the greatest gains in function and pain relief following their TJRs. However, there were no significant differences in pain or function at 12-month follow-up between patients who scored low and those who scored high on preoperative WOMAC and SF-36 surveys. Conclusion. Patients with poor preoperative functional status had greater improvement but similar 12-month functional outcomes compared with patients who had a higher level of function before surgery. These results suggest that a policy of focusing scarce resources on patients with worse functional status in developing countries may optimize improvement following TJR without threatening functional outcome. Additional research is needed to confirm these findings in other developing countries and to understand why these associations vary between patients in the Dominican Republic and patients from developed countries. PMID:23748412

  17. Initially unresectable rectal adenocarcinoma treated with preoperative irradiation and surgery

    SciTech Connect

    Mendenhall, W.M.; Million, R.R.; Bland, K.I.; Pfaff, W.W.; Copeland, E.M. 3d.

    1987-01-01

    This is an analysis of 23 patients with clinically and/or surgically unresectable adenocarcinoma of the rectum on initial evaluation who were treated with preoperative irradiation and surgery between March 1970 and April 1981. All patients have had follow-up for at least 5 years. Five patients (22%) had exploratory laparotomy and diverting colostomy before irradiation. All patients were irradiated with megavoltage equipment to the pelvis at 180 rad/fraction, continuous-course technique. Total doses ranged from 3500 to 6000 rad with a mean of 4800 rad and a median of 5000 rad. All patients had surgery 2-11 weeks (mean: 4.9 weeks; median: 4 weeks) after radiation therapy. Twelve patients (52%) had lesions that were incompletely resected because of positive margins (7 patients), distant metastasis (1 patient), or both (4 patients). All of these patients died of cancer within 5 years of treatment. Eleven patients had an apparent complete excision of their rectal cancer; six patients (55%) subsequently had a local recurrence. The 5-year absolute survival rate for patients who had complete resection was 18% (2 of 11 patients). The 5-year absolute and determinate survival rates for the entire study were 9% (2 of 23 patients) and 9% (2 of 22 patients), respectively. One patient (in the incomplete resection group) died after operation secondary to sepsis and diffuse intravascular coagulation.

  18. Effect of preoperative mastoid ventilation on tympanoplasty success.

    PubMed

    Metin, Mehmet; Kaptan, Zeynep Kizilkaya; Dogan, Sedat; Yazici, Hasmet; Bayraktar, Cem; Gocmen, Hakan; Samim, Etem Erdal

    2014-01-01

    Purpose. This study was conducted with the aim of investigating the relationship between mastoid air cell volumes and graft success after tympanoplasty. Material and Methods. This study was performed retrospectively with patients undergoing type I tympanoplasty and antrostomy. A total of 57 patients (20-35.09% female and 37-64.91% male) with a mean age of 29.69 ± SD (range 12-56 years) were included in the study. The patients were invited for a control at the 1st, 3rd, and 12th months, and otoscopic examinations and audiometric tests were performed. The temporal bone computed tomography images were screened with the 4800 Dpi optic resolution scanner and transferred to the computer environment in JPG format in order to calculate the mastoid air cell volume, and the volumes were calculated using the Autocad 2007 program. Results. Although, the graft success was determined to be better in the well-ventilated group, no significant difference could be found between the groups in terms of graft success at the 1st, 3rd, and 12th months (P > 0.05). No statistically significant difference could be found between the three groups in terms of the preoperative and postoperative hearing gains (P > 0.05). PMID:25374605

  19. Effect of Preoperative Mastoid Ventilation on Tympanoplasty Success

    PubMed Central

    Metin, Mehmet; Kaptan, Zeynep Kizilkaya; Dogan, Sedat; Yazici, Hasmet; Bayraktar, Cem; Gocmen, Hakan; Samim, Etem Erdal

    2014-01-01

    Purpose. This study was conducted with the aim of investigating the relationship between mastoid air cell volumes and graft success after tympanoplasty. Material and Methods. This study was performed retrospectively with patients undergoing type I tympanoplasty and antrostomy. A total of 57 patients (20–35.09% female and 37–64.91% male) with a mean age of 29.69 ± SD (range 12–56 years) were included in the study. The patients were invited for a control at the 1st, 3rd, and 12th months, and otoscopic examinations and audiometric tests were performed. The temporal bone computed tomography images were screened with the 4800 Dpi optic resolution scanner and transferred to the computer environment in JPG format in order to calculate the mastoid air cell volume, and the volumes were calculated using the Autocad 2007 program. Results. Although, the graft success was determined to be better in the well-ventilated group, no significant difference could be found between the groups in terms of graft success at the 1st, 3rd, and 12th months (P > 0.05). No statistically significant difference could be found between the three groups in terms of the preoperative and postoperative hearing gains (P > 0.05). PMID:25374605

  20. Meniscal allograft transplantation: preoperative assessment, surgical considerations, and clinical outcomes.

    PubMed

    Mascarenhas, Randy; Yanke, Adam B; Frank, Rachel M; Butty, Davietta C; Cole, Brian J

    2014-12-01

    The purpose of this review is to characterize the preoperative assessment of meniscal allograft transplantation (MAT) candidates, to detail MAT surgical techniques, and to evaluate current clinical outcome data on MAT. The MAT candidate is typically less than 50 years old and has a history of knee injury, previous meniscus surgery, and persistent pain. Physical exam generally reveals knee pain with joint line tenderness with normal radiographs and magnetic resonance imaging demonstrating the postmeniscectomized state. There are several common surgical techniques used for transplantation, with fixation achieved through sutures, bony fixation, or a combination of the two. Concomitant procedures such as anterior cruciate ligament reconstruction, osteotomy, and other cartilage procedures are commonly performed. The available short- and long-term studies of clinical outcomes of MAT are variable and difficult to effectively compare due to heterogeneity of the study population and available treatment techniques. In addition, there are no published randomized controlled trials. However, recent reviews and cohort studies of clinical outcomes following MAT have shown that whether performed in isolation or performed with concomitant articular cartilage, realignment, or soft tissue reconstruction procedures MAT outcomes have been acceptable with the majority of studies reporting improved clinical outcomes regardless of the scoring system employed. MAT has proven to be a safe and effective technique in reducing knee pain and improving function in the symptomatic meniscal deficient knee. Evaluation of long-term clinical outcomes is necessary as is evaluation of meniscal replacement alternatives. PMID:24951950

  1. Preoperative glucose abnormalities in patients with pancreatic tumours

    PubMed Central

    Durlik, Marek; Kałuża, Bernadetta; Milczarczyk, Alicja; Franek, Edward

    2014-01-01

    Introduction Pancreatic cancer is a neoplasm characterised by poor prognosis. The only effective, possible treatment is radical surgery, but most patients do not qualify for surgery because of delayed diagnosis. Aim To determine if assessment of endocrine pancreatic function could serve as a means of screening for pancreatic cancer. Material and methods This prospective study was conducted on a group of 50 patients diagnosed with pancreatic tumour, who were qualified for surgery. Results From 1.07.2010 to 4.07.2011 a further 50 patients were added to the study group. They had been admitted to the hospital with pancreatic tumours. During the preoperative period, nine of these people had been treated for diabetes, 14 were newly diagnosed with diabetes and 15 had been diagnosed with impaired glucose tolerance, but only 12 had a normal glucose profile. Afterwards, patients underwent the surgical treatment. Histopathological examination revealed that out of the 50 operated patients, 36 suffered from malignant disease, and of these only four had no impaired glucose tolerance before treatment. Conclusions In most cases, patients with pancreatic tumours have impaired glucose tolerance. Screening patients over 50 years of age could speed up diagnosis and surgical treatment. PMID:25061491

  2. MRI for the preoperative evaluation of femoroacetabular impingement.

    PubMed

    Li, Angela E; Jawetz, Shari T; Greditzer, Harry G; Burge, Alissa J; Nawabi, Danyal H; Potter, Hollis G

    2016-04-01

    Femoroacetabular impingement (FAI) refers to a condition characterized by impingement of the femoral head-neck junction against the acetabular rim, often due to underlying osseous and/or soft tissue morphological abnormalities. It is a common cause of hip pain and limited range of motion in young and middle-aged adults. Hip preservation surgery aims to correct the morphological variants seen in FAI, thereby relieving pain and improving function, and potentially preventing early osteoarthritis. The purpose of this article is to review the mechanisms of chondral and labral injury in FAI to facilitate an understanding of patterns of chondrolabral injury seen on MRI. Preoperative MRI evaluation of FAI should include assessment of osseous morphologic abnormalities, labral tears, cartilage status, and other associated compensatory injuries of the pelvis. As advanced chondral wear is the major relative contraindication for hip preservation surgery, MRI is useful in the selection of patients likely to benefit from surgery. Teaching points • The most common anatomical osseous abnormalities predisposing to FAI include cam and pincer lesions. • Morphological abnormalities, labral lesions, and cartilage status should be assessed. • In cam impingement, chondral wear most commonly occurs anterosuperiorly.• Pre-existing advanced osteoarthritis is the strongest predictor of poor outcomes after FAI surgery. • Injury to muscles and tendons or other pelvic structures can coexist with FAI. PMID:26715128

  3. Effect of preoperative suggestion on postoperative gastrointestinal motility.

    PubMed Central

    Disbrow, E A; Bennett, H L; Owings, J T

    1993-01-01

    Autonomic behavior is subject to direct suggestion. We found that patients undergoing major operations benefit more from instruction than from information and reassurance. We compared the return of intestinal function after intra-abdominal operations in 2 groups of patients: the suggestion group received specific instructions for the early return of gastrointestinal motility, and the control group received an equal-length interview offering reassurance and nonspecific instructions. The suggestion group had a significantly shorter average time to the return of intestinal motility, 2.6 versus 4.1 days. Time to discharge was 6.5 versus 8.1 days. Covariates including duration of operation, amount of intraoperative bowel manipulation, and amount of postoperative narcotics were also examined using the statistical model analysis of covariance. An average savings of $1,200 per patient resulted from this simple 5-minute intervention. In summary, the use of specific physiologically active suggestions given preoperatively in a beleivable manner can reduce the morbidity associated with an intra-abdominal operation by reducing the duration of ileus. PMID:8342264

  4. Preoperative gastric emptying. Effects of anxiety and oral carbohydrate administration.

    PubMed Central

    Nygren, J; Thorell, A; Jacobsson, H; Larsson, S; Schnell, P O; Hylén, L; Ljungqvist, O

    1995-01-01

    BACKGROUND: Overnight fasting is routine before elective surgery. This may not be the optimal way to prepare for surgical stress, however, because intravenous carbohydrate supplementation instead of fasting has recently been shown to reduce postoperative insulin resistance. In the current study, gastric emptying of a carbohydrate-rich drink was investigated before elective surgery and in a control situation. METHODS: Twelve patients scheduled for elective surgery were randomly given 400 mL of either a carbohydrate-rich drink (285 mOsm/kg, 12.0% carbohydrates, n = 6) or water 4 hours before being anesthetized. Gastric emptying was measured (gamma camera, 99Tcm). Each patient repeated the protocol postoperatively as a control. All values were presented as the mean +/- SEM by means of a nonparametric statistical evaluation. RESULTS: Despite the increased anxiety experienced by patients before surgery (p < 0.005), gastric emptying did not differ between the experimental and control situations. Initially, water emptied more rapidly than carbohydrate. However, after 90 minutes, the stomach was emptied regardless of the solution administered (3.2 +/- 1.1% [mean +/- SEM] remaining in the stomach in the carbohydrate group versus 2.3 +/- 1.2% remaining in the stomach in the water group). CONCLUSIONS: Preoperative anxiety does not prolong gastric emptying. The stomach had been emptied 90 minutes after ingestion of both the carbohydrate-rick drink and water, thereby indicating the possibility of allowing an intake of iso-osmolar carbohydrate-rich fluids before surgery. PMID:8526579

  5. Preoperative portal vein embolization for hepatocellular carcinoma: Consensus and controversy

    PubMed Central

    Aoki, Taku; Kubota, Keiichi

    2016-01-01

    Thirty years have passed since the first report of portal vein embolization (PVE), and this procedure is widely adopted as a preoperative treatment procedure for patients with a small future liver remnant (FLR). PVE has been shown to be useful in patients with hepatocellular carcinoma (HCC) and chronic liver disease. However, special caution is needed when PVE is applied prior to subsequent major hepatic resection in cases with cirrhotic livers, and volumetric analysis of the liver segments in addition to evaluation of the liver functional reserve before PVE is mandatory in such cases. Advances in the embolic material and selection of the treatment approach, and combined use of PVE and transcatheter arterial embolization/chemoembolization have yielded improved outcomes after PVE and major hepatic resections. A novel procedure termed the associating liver partition and portal vein ligation for staged hepatectomy has been gaining attention because of the rapid hypertrophy of the FLR observed in patients undergoing this procedure, however, application of this technique in HCC patients requires special caution, as it has been shown to be associated with a high morbidity and mortality even in cases with essentially healthy livers. PMID:27028706

  6. Inverted Meckel's diverticulum preoperatively diagnosed using double-balloon enteroscopy.

    PubMed

    Takagaki, Kosuke; Osawa, Satoshi; Ito, Tatsuhiro; Iwaizumi, Moriya; Hamaya, Yasushi; Tsukui, Hiroe; Furuta, Takahisa; Wada, Hidetoshi; Baba, Satoshi; Sugimoto, Ken

    2016-05-01

    An inverted Meckel's diverticulum is a rare gastrointestinal congenital anomaly that is difficult to diagnose prior to surgery and presents with anemia, abdominal pain, or intussusception. Here, we report the case of 57-year-old men with an inverted Meckel's diverticulum, who was preoperatively diagnosed using double-balloon enteroscopy. He had repeatedly experienced epigastric pain for 2 mo. Ultrasonography and computed tomography showed intestinal wall thickening in the pelvis. Double-balloon enteroscopy via the anal route was performed for further examination, which demonstrated an approximately 8-cm, sausage-shaped, submucosal tumor located approximately 80 cm proximal to the ileocecal valve. A small depressed erosion was observed at the tip of this lesion. Forceps biopsy revealed heterotopic gastric mucosa. Thus, the patient was diagnosed with an inverted Meckel's diverticulum, and single-incision laparoscopic surgery was performed. This case suggests that an inverted Meckel's diverticulum should be considered as a differential diagnosis for a submucosal tumor in the ileum. Balloon-assisted enteroscopy with forceps biopsy facilitate a precise diagnosis of this condition. PMID:27158212

  7. An analysis of a preoperative pediatric autologous blood donation program

    PubMed Central

    Letts, Merv; Perng, Richard; Luke, Brian; Jarvis, James; Lawton, Louis; Hoey, Steve

    2000-01-01

    Objective To determine the efficacy of a pediatric autologous blood donation program. Design A retrospective study of patient charts and blood-bank records. Setting The Children’s Hospital of Eastern Ontario, Ottawa, a tertiary care, pediatric centre. Patients One hundred and seventy-three children who received blood transfusions for a total of 182 procedures between June 1987 and June 1997. Interventions Autologous and homologous blood transfusion required for major surgical intervention, primarily spinal fusion. Main outcome measures Surgeons’ accuracy in predicting the number of autologous blood units required for a given procedure, compliance rate (children’s ability to donate the requested volume of blood), utilization rate of autologous units and rate of allogeneic transfusion. Results The surgeons’ accuracy in predicting the number of autologous units required for a given procedure was 53.8%. The compliance rate of children to donate the requested amount of blood was 80.3%. In children below the standard age and weight criteria for blood donation the compliance rate was 75.5%. The utilization rate of autologous units obtained was 84.4% and the incidence of allogeneic transfusion was 26.6%. Conclusions There was a high rate of compliance and utilization of predonated autologous blood in the children in the study. Preoperative blood donation programs are safe and effective in children, even in those below the standard age and weight criteria of 10 years and 40 kg. PMID:10812347

  8. Drug Combinations in Preoperative Chemoradiation for Rectal Cancer.

    PubMed

    Glynne-Jones, Rob; Carvalho, Carlos

    2016-07-01

    Preoperative radiotherapy has an accepted role in reducing the risk of local recurrence in locally advanced resectable rectal cancer, particularly when the circumferential resection margin is breached or threatened, according to magnetic resonance imaging. Fluoropyrimidine-based chemoradiation can obtain a significant down-sizing response and a curative resection can then be achieved. Approximately, 20% of the patients can also obtain a pathological complete response, which is associated with less local recurrences and increased survival. Patients who achieve a sustained complete clinical response may also avoid radical surgery. In unresectable or borderline resectable tumors, around 20% of the patients still fail to achieve a sufficient down-staging response with the current chemoradiation schedules. Hence, investigators have aspired to increase pathological complete response rates, aiming to improve curative resection rates, enhance survival, and potentially avoid mutilating surgery. However, adding additional cytotoxic or biological agents have not produced dramatic improvements in outcome and often led to excess surgical morbidity and higher levels of acute toxicity, which effects on compliance and in the global efficacy of chemoradiation. PMID:27238473

  9. Impact of preoperative patient education on prevention of postoperative complications after major visceral surgery: study protocol for a randomized controlled trial (PEDUCAT trial)

    PubMed Central

    2013-01-01

    Background In line with the growing number of surgical procedures being performed worldwide, postoperative complications are also increasing proportionately. Prevention of these postoperative complications is a high medical priority. Preoperative education of patients, including provision of preparatory information about the correct behavior after surgery, could improve the postoperative outcome, but the evidence for this is inconclusive. The aim of the PEDUCAT trial is to evaluate the feasibility and the impact of preoperative patient education on postoperative morbidity, mortality and quality of life in patients scheduled for elective major visceral surgery. Methods/design PEDUCAT is designed as a cluster-randomized controlled pilot study. The experimental group will visit a standardized preoperative seminar to learn how best to behave after surgery in addition to being given a standard information brochure, whereas the control group will only receive the information brochure. Outcome measures such as postoperative morbidity, postoperative pain, postoperative anxiety and depression, patient satisfaction, quality of life, length of hospital stay and postoperative mortality will be evaluated. Statistical analysis will be based on the intention-to-treat population. Analysis of covariance will be applied for the intervention group comparison, adjusting for age, center and quality of life before surgery. This is a pilot study to show the feasibility of the concept. Nevertheless, the planned sample size of n = 204 is large enough to show an effect with power of 90% and a significance level of 5%. Trial registration German Clinical Trial Register number: DRKS00004226. PMID:23978275

  10. Preoperative pain treatment in acute abdomen in Osogbo, Nigeria: a randomized double-blind placebo-controlled study

    PubMed Central

    2013-01-01

    Background Withholding analgesics in acute abdomen for fear of masking clinical features and impairing diagnosis and decision-making is still being practiced despite recent evidence to the contrary. This study assesses the effect of preoperative analgesia on clinical findings, clinical diagnosis, and decision-making in patients with non-trauma acute abdomen. Method This is a randomized, double-blind, placebo-controlled study using Tramal, a brand of tramadol, at the ED of LAUTECH Teaching Hospital Osogbo, Nigeria. Ninety-five patients between 18–60 years received Tramal (n = 46) or placebo (n = 49). The pain score, clinical findings, provisional diagnosis, and treatment plan were noted before and 15–20 min after administration of the analgesic or placebo. The final diagnosis arrived at after adequate investigation or operation was considered the gold standard. The pain scores, diagnosis, treatment plan, and decision between the two groups were compared. Statistical analysis was by SPSS 16. Results were considered statistically significant at p < 0.05. Results Demography and case distribution were similar in both groups. The improvement in pain was greater in the Tramal group (p = 0.001). The abdominal palpation findings were also better in the Tramal group (p = 0.02). There were more changes in the diagnosis after use of Tramal (p = 0.01). There were more changes in the decision in the Tramal group (p = 0.03). Most of the changes in diagnosis and decision in the Tramal group were for the better. Conclusion The preoperative use of Tramal in acute abdomen improved the experience of pain and did not adversely affect the accuracy of the diagnosis or decision-making. PMID:23343476

  11. The activated coagulation time of whole blood as a routine pre-operative sceening test.

    PubMed

    Hattersley, P G

    1971-05-01

    Patients with disorders of hemostasis who undergo surgical procedures are in danger of hemorrhage. While the careful medical history remains the most sensitive test of a bleeding tendency, some such patients can give no suggestive history. In three patients with coagulopathy-one with mild classical hemophilia, one with Christmas disease, and one with warfarin toxicity-the abnormality was missed by routine preoperative history but promptly detected by the routine preoperative use of the activated coagulation time (act). Either this test or the activated partial thromboplastin time should be included in the routine preoperative work-up, along with appropriate additional tests of the hemostatic mechanism. PMID:5087876

  12. The Activated Coagulation Time of Whole Blood as a Routine Pre-Operative Screening Test

    PubMed Central

    Hattersley, Paul G.

    1971-01-01

    Patients with disorders of hemostasis who undergo surgical procedures are in danger of hemorrhage. While the careful medical history remains the most sensitive test of a bleeding tendency, some such patients can give no suggestive history. In three patients with coagulopathy—one with mild classical hemophilia, one with Christmas disease, and one with warfarin toxicity—the abnormality was missed by routine preoperative history but promptly detected by the routine preoperative use of the activated coagulation time (act). Either this test or the activated partial thromboplastin time should be included in the routine preoperative work-up, along with appropriate additional tests of the hemostatic mechanism. PMID:5087876

  13. An Effective Preoperative Three-Dimensional Radiotherapy Target Volume for Extremity Soft Tissue Sarcoma and the Effect of Margin Width on Local Control

    SciTech Connect

    Kim, Bo Kyong; Chen, Yen-Lin E.; Kirsch, David G.; Goldberg, Saveli I.; Kobayashi, Wendy; Kung, Jong Hyun; Wolfgang, John A.; Doppke, Karen

    2010-07-01

    Purpose: There is little information on the appropriate three-dimensional (3D) preoperative radiotherapy (XRT) volume for extremity soft-tissue sarcomas (STS). We retrospectively analyzed the pattern of local failure (LF) to help elucidate optimal field design. Methods and Materials: We analyzed the 56 patients who underwent computed tomography-planned XRT for Stage I to III extremity STS between June 2000 and December 2006. Clinical target volume (CTV) included the T1 post-gadolinium-defined gross tumor volume with 1- to 1.5-cm radial and 3.5-cm longitudinal margins. Planning target volume expansion was 5 to 7 mm, and {>=}95% of dose was delivered to the planning target volume. Preoperative XRT was 44 to 50.4 Gy (median, 50). Postoperative boost of 10 to 20 Gy was given to 12 patients (6 with positive and 6 with close margins). Results: Follow-up ranged from 15 to 76 months (median, 41 months). The 5-year local control, freedom from distant metastasis, disease-free survival, and overall survival were 88.5%, 80.0%, 77.5% and 82.8%, respectively. Three patients (all with positive margin) experienced local failure (LF) as first relapse (2 isolated, 1 with distant failure), and 2 additional patients (all with margin<1 mm) had late LF after distant metastasis. The LFs were within the CTV in 3 patients and within and also extending beyond the CTV in 2 patients. Conclusions: These target volume definitions appear to be appropriate for most patients. No local recurrences were observed with surgical margins {>=}1 mm, and it appears that these may be adequate for patients with extremity STS treated with preoperative radiotherapy.

  14. A highly accurate interatomic potential for argon

    NASA Astrophysics Data System (ADS)

    Aziz, Ronald A.

    1993-09-01

    A modified potential based on the individually damped model of Douketis, Scoles, Marchetti, Zen, and Thakkar [J. Chem. Phys. 76, 3057 (1982)] is presented which fits, within experimental error, the accurate ultraviolet (UV) vibration-rotation spectrum of argon determined by UV laser absorption spectroscopy by Herman, LaRocque, and Stoicheff [J. Chem. Phys. 89, 4535 (1988)]. Other literature potentials fail to do so. The potential also is shown to predict a large number of other properties and is probably the most accurate characterization of the argon interaction constructed to date.

  15. Predictive role of preoperative lymphoscintigraphy on the status of the sentinel lymph node in clinically node-negative patients with cutaneous melanoma.

    PubMed

    Solari, Nicola; Gipponi, Marco; Stella, Mattia; Queirolo, Paola; di Somma, Carmine; Villa, Giuseppe; Piccardo, Arnoldo; Gualco, Marina; Cardinale, Francesco; Cafiero, Ferdinando

    2009-08-01

    We reviewed our experience to assess the predictive role of preoperative lymphoscintigraphy with regard to the pathological status of sentinel lymph node (sN) in patients with cutaneous melanoma, to optimize the surgical treatment planning with regard to the use of intraoperative frozen section examination of sN. Eighty-eight patients with clinically node-negative cutaneous melanoma pT1b-T4 stage underwent preoperative lymphoscintigraphy for the lymphatic mapping of sN. A lymphoscintigraphic 'score' (from L1 to L5) was developed based on the ratio of radiotracer concentration within sN nodes as compared with the injection site. Our score allowed us to foresee that sN of patients with thick melanomas (T3 and T4) and a low preoperative score (L1-L2-L3) had a 90% expected likelihood (P<0.001) of harboring metastasis, whereas sN in patients with thin melanomas (T1b-T2) and high preoperative score (from L4 to L5) showed a 100% likelihood of being metastasis free. In conclusion, the sN is a reliable predictor of regional lymph node status in patients with cutaneous malignant melanoma. Moreover, we suggest that a low score (L1-L2-L3) associated with a thick melanoma is a good predictive factor of the positive sN involvement. This information could be useful in scheduling the intraoperative frozen-section examination with an expected benefit of a positive test in almost 90% of patients. Such patients might be selected for a 'one-stage' procedure with a more effective cost/benefit ratio and decreased hospitalization costs. PMID:19584766

  16. Pre-Operative Image-based Segmentation of the Cranial Nerves and Blood Vessels in Microvascular Decompression: Can we Prevent Unnecessary Explorations?

    PubMed Central

    Dolati, P; Golby, A; Eichberg, D; Abolfotoh, M; Dunn, IF; Mukundan, S; Hulou, MM; Al-Mefty, O

    2016-01-01

    Objectives This study was conducted to validate the accuracy of image-based pre-operative segmentation using the gold standard endoscopic and microscopic findings for localization and pre-operative diagnosis of the offensive vessel. Patients and Methods Fourteen TN and 6 HS cases were randomly selected. All patients had 3T MRI, which included thin-sectioned 3D space T2, 3D Time of Flight and MPRAGE Sequences. Imaging sequences were loaded in BrainLab iPlanNet and fused. Individual segmentation of the affected cranial nerves and the compressing vascular structure was performed by a neurosurgeon, and the results were compared with the microscopic and endoscopic findings by two blinded neurosurgeons. For each case, at least three neurovascular landmarks were targeted. Each segmented neurovascular element was validated by manual placement of the navigation probe over each target, and errors of localization were measured in mm. Results All patients underwent retro-sigmoid craniotomy and MVD using both microscope and endoscope. Based on image segmentation, the compressing vessel was identified in all cases except one, which was also negative intraoperatively. Perfect correspondence was found between image-based segmentation and endoscopic and microscopic images and videos (Dice coefficient of 1). Measurement accuracy was 0.45+/-0.21 mm (mean +/-SD). Conclusion Image-based segmentation is a promising method for pre-operative identification and localization of offending blood vessels causing HFS and TN. Using this method may prevent some unnecessary explorations on especially atypical cases with no vascular contacts. However, negative pre-operative image segmentation may not preclude one from exploration in classic cases of TN or HFS. A multicenter study with larger number of cases is recommended. PMID:26476700

  17. Accurate pointing of tungsten welding electrodes

    NASA Technical Reports Server (NTRS)

    Ziegelmeier, P.

    1971-01-01

    Thoriated-tungsten is pointed accurately and quickly by using sodium nitrite. Point produced is smooth and no effort is necessary to hold the tungsten rod concentric. The chemically produced point can be used several times longer than ground points. This method reduces time and cost of preparing tungsten electrodes.

  18. Complication avoidance with pre-operative screening: insights from the Seattle spine team.

    PubMed

    Buchlak, Quinlan D; Yanamadala, Vijay; Leveque, Jean-Christophe; Sethi, Rajiv

    2016-09-01

    Complication rates for complex adult lumbar scoliosis surgery are unacceptably high. Standardized preoperative evaluation protocols have been shown to significantly reduce the likelihood of a spectrum of negative outcomes associated with complex adult lumbar scoliosis surgery. To increase patient safety and reduce complication risk, an entire medical and surgical team should work together to care for adult lumbar scoliosis patients. This article describes preoperative patient evaluation strategies with a particular focus on adult lumbar scoliosis surgery involving six or more levels of spinal fusion. Domains considered include recent preoperative evaluation literature, predictive risk modeling, the appropriate management of medical conditions, and the composition and activities of a multidisciplinary conference review team. An evidence-based comprehensive systematic preoperative surgical evaluation process is described. PMID:27260267

  19. Preoperational Environmental Survey for the Spent Nuclear Fuel (SNF) Project Facilities

    SciTech Connect

    MITCHELL, R.M.

    2000-09-28

    This document represents the report for environmental sampling of soil, vegetation, litter, cryptograms, and small mammals at the Spent Nuclear Fuel Project facilities located in 100 K and 200 East Areas in support of the preoperational environmental survey.

  20. Preoperational Environmental Survey for the Spent Nuclear Fuel (SNF) Project Facilities

    SciTech Connect

    MITCHELL, R.M.

    2000-10-12

    This document represents the report for environmental sampling of soil, vegetation, litter, cryptograms, and small mammals at the Spent Nuclear Fuel Project facilities located in 100 K and 200 East Areas in support of the preoperational environmental survey.

  1. Prevention and intervention strategies to alleviate preoperative anxiety in children: a critical review.

    PubMed

    Wright, Kristi D; Stewart, Sherry H; Finley, G Allen; Buffett-Jerrott, Susan E

    2007-01-01

    Preoperative anxiety (anxiety regarding impending surgical experience) in children is a common phenomenon that has been associated with a number of negative behaviors during the surgery experience (e.g., agitation, crying, spontaneous urination, and the need for physical restraint during anesthetic induction). Preoperative anxiety has also been associated with the display of a number of maladaptive behaviors postsurgery, including postoperative pain, sleeping disturbances, parent-child conflict, and separation anxiety. For these reasons, researchers have sought out interventions to treat or prevent childhood preoperative anxiety and possibly decrease the development of negative behaviors postsurgery. Such interventions include sedative premedication, parental presence during anesthetic induction, behavioral preparation programs, music therapy, and acupuncture. The present article reviews the existing research on the various modes of intervention for preoperative anxiety in children. Clinical implications and future directions are discussed. PMID:17179531

  2. Use of pre-operative steroids in liver resection: a systematic review and meta-analysis

    PubMed Central

    Richardson, Arthur J; Laurence, Jerome M; Lam, Vincent WT

    2014-01-01

    Background By attenuating the systemic inflammatory response to major surgery, the pre-operative administration of steroids may reduce the incidence of complications. Methods A systematic review was conducted to identify randomized controlled trials (RCT) comparing pre-operative steroid administration with placebo during a liver resection. Meta-analyses were performed. Results Five RCTs were identified including a total of 379 patients. Pre-operative steroids were associated with statistically significant reductions in the levels of serum bilirubin and interleukin 6 (IL-6) on post-operative day one. There was a trend towards a lower incidence of post-operative complications and prothrombin time (PT), but this did not reach statistical significance. Conclusion Pre-operative steroids may be associated with a clinically significant benefit in liver resection. PMID:23461716

  3. Preoperative Identification of a Perforator Using Computed Tomography Angiography and Metal Clip Marking in Perforator Flap Reconstruction

    PubMed Central

    Lee, Jung Woo; Kim, Han Kyeol; Kim, Sin Rak; Han, Yea Sik

    2015-01-01

    In perforator flap reconstruction, vascular mapping using preoperative computed tomography (CT) angiography is widely used to confirm the existence and location of an appropriate perforator. This study proposes a rapid, accurate, and convenient method for marking the perforator location on the skin surface. For 12 patients who underwent perforator flap reconstruction between November 2011 and November 2013, metal clips were fixed on the skin surface at the anticipated perforator locations, which were decided using a handheld Doppler. CT angiography was used to compare the location between the metal clip and the actual perforator. The metal clip was moved and repositioned, if needed, on the basis of the CT images. The locations of the appropriate perforator and the metal clip, which were observed during the surgery, were then compared. In CT angiography, the mean distance between the metal clip and the perforator was 3±3.9 mm, and the mean distance that was measured during surgery was 0.8±0.8 mm. In conclusion, we report a simple, rapid, and precise technique to indicate the accurate location of the appropriate perforator on the skin surface. PMID:25606494

  4. Differential Network Analysis Applied to Preoperative Breast Cancer Chemotherapy Response

    PubMed Central

    Warsow, Gregor; Struckmann, Stephan; Kerkhoff, Claus; Reimer, Toralf; Engel, Nadja; Fuellen, Georg

    2013-01-01

    In silico approaches are increasingly considered to improve breast cancer treatment. One of these treatments, neoadjuvant TFAC chemotherapy, is used in cases where application of preoperative systemic therapy is indicated. Estimating response to treatment allows or improves clinical decision-making and this, in turn, may be based on a good understanding of the underlying molecular mechanisms. Ever increasing amounts of high throughput data become available for integration into functional networks. In this study, we applied our software tool ExprEssence to identify specific mechanisms relevant for TFAC therapy response, from a gene/protein interaction network. We contrasted the resulting active subnetwork to the subnetworks of two other such methods, OptDis and KeyPathwayMiner. We could show that the ExprEssence subnetwork is more related to the mechanistic functional principles of TFAC therapy than the subnetworks of the other two methods despite the simplicity of ExprEssence. We were able to validate our method by recovering known mechanisms and as an application example of our method, we identified a mechanism that may further explain the synergism between paclitaxel and doxorubicin in TFAC treatment: Paclitaxel may attenuate MELK gene expression, resulting in lower levels of its target MYBL2, already associated with doxorubicin synergism in hepatocellular carcinoma cell lines. We tested our hypothesis in three breast cancer cell lines, confirming it in part. In particular, the predicted effect on MYBL2 could be validated, and a synergistic effect of paclitaxel and doxorubicin could be demonstrated in the breast cancer cell lines SKBR3 and MCF-7. PMID:24349128

  5. Differential network analysis applied to preoperative breast cancer chemotherapy response.

    PubMed

    Warsow, Gregor; Struckmann, Stephan; Kerkhoff, Claus; Reimer, Toralf; Engel, Nadja; Fuellen, Georg

    2013-01-01

    In silico approaches are increasingly considered to improve breast cancer treatment. One of these treatments, neoadjuvant TFAC chemotherapy, is used in cases where application of preoperative systemic therapy is indicated. Estimating response to treatment allows or improves clinical decision-making and this, in turn, may be based on a good understanding of the underlying molecular mechanisms. Ever increasing amounts of high throughput data become available for integration into functional networks. In this study, we applied our software tool ExprEssence to identify specific mechanisms relevant for TFAC therapy response, from a gene/protein interaction network. We contrasted the resulting active subnetwork to the subnetworks of two other such methods, OptDis and KeyPathwayMiner. We could show that the ExprEssence subnetwork is more related to the mechanistic functional principles of TFAC therapy than the subnetworks of the other two methods despite the simplicity of ExprEssence. We were able to validate our method by recovering known mechanisms and as an application example of our method, we identified a mechanism that may further explain the synergism between paclitaxel and doxorubicin in TFAC treatment: Paclitaxel may attenuate MELK gene expression, resulting in lower levels of its target MYBL2, already associated with doxorubicin synergism in hepatocellular carcinoma cell lines. We tested our hypothesis in three breast cancer cell lines, confirming it in part. In particular, the predicted effect on MYBL2 could be validated, and a synergistic effect of paclitaxel and doxorubicin could be demonstrated in the breast cancer cell lines SKBR3 and MCF-7. PMID:24349128

  6. Rigid 2D/3D registration of intraoperative digital x-ray images and preoperative CT and MR images

    NASA Astrophysics Data System (ADS)

    Tomazevic, Dejan; Likar, Bostjan; Pernus, Franjo

    2002-05-01

    This paper describes a novel approach to register 3D computed tomography (CT) or magnetic resonance (MR) images to a set of 2D X-ray images. Such a registration may be a valuable tool for intraoperative determination of the precise position and orientation of some anatomy of interest, defined in preoperative images. The registration is based solely on the information present in 2D and 3D images. It does not require fiducial markers, X-ray image segmentation, or construction of digitally reconstructed radiographs. The originality of the approach is in using normals to bone surfaces, preoperatively defined in 3D MR or CT data, and gradients of intraoperative X-ray images, which are back-projected towards the X-ray source. The registration is then concerned with finding that rigid transformation of a CT or MR volume, which provides the best match between surface normals and back projected gradients, considering their amplitudes and orientations. The method is tested on a lumbar spine phantom. Gold standard registration is obtained by fidicual markers attached to the phantom. Volumes of interest, containing single vertebrae, are registered to different pairs of X-ray images from different starting positions, chosen randomly and uniformly around the gold standard position. Target registration errors and rotation errors are in order of 0.3 mm and 0.35 degrees for the CT to X-ray registration and 1.3 mm and 1.5 degrees for MR to X-ray registration. The registration is shown to be fast and accurate.

  7. Effects of deformable registration algorithms on the creation of statistical maps for preoperative targeting in deep brain stimulation procedures

    NASA Astrophysics Data System (ADS)

    Liu, Yuan; D'Haese, Pierre-Francois; Dawant, Benoit M.

    2014-03-01

    Deep brain stimulation, which is used to treat various neurological disorders, involves implanting a permanent electrode into precise targets deep in the brain. Accurate pre-operative localization of the targets on pre-operative MRI sequence is challenging as these are typically located in homogenous regions with poor contrast. Population-based statistical atlases can assist with this process. Such atlases are created by acquiring the location of efficacious regions from numerous subjects and projecting them onto a common reference image volume using some normalization method. In previous work, we presented results concluding that non-rigid registration provided the best result for such normalization. However, this process could be biased by the choice of the reference image and/or registration approach. In this paper, we have qualitatively and quantitatively compared the performance of six recognized deformable registration methods at normalizing such data in poor contrasted regions onto three different reference volumes using a unique set of data from 100 patients. We study various metrics designed to measure the centroid, spread, and shape of the normalized data. This study leads to a total of 1800 deformable registrations and results show that statistical atlases constructed using different deformable registration methods share comparable centroids and spreads with marginal differences in their shape. Among the six methods being studied, Diffeomorphic Demons produces the largest spreads and centroids that are the furthest apart from the others in general. Among the three atlases, one atlas consistently outperforms the other two with smaller spreads for each algorithm. However, none of the differences in the spreads were found to be statistically significant, across different algorithms or across different atlases.

  8. Preoperative Steroid Use and the Risk of Infectious Complications After Neurosurgery

    PubMed Central

    Merkler, Alexander E.; Saini, Vaishali; Kamel, Hooman; Stieg, Philip E.

    2014-01-01

    Background and Purpose: The association between preoperative corticosteroid use and infectious complications after neurosurgical procedures is unclear. We aim to determine whether corticosteroids increase the risk of infectious complications after neurosurgery. Methods: We examined the association between preoperative corticosteroid use and postoperative infectious complications in a cohort of adults who underwent a neurosurgical procedure between 2005 and 2010 at centers participating in the National Surgical Quality Improvement Program. Corticosteroid use was defined as at least 10 days of oral or parental therapy in the 30 days prior to surgery. Our primary outcome was a composite of any infectious complications occurring within 30 days of surgery. We used propensity score analysis to examine the independent association between preoperative corticosteroid use and postoperative infections. Results: Among 26 634 neurosurgical procedures, 1228 (4.61%, 95% confidence interval [CI], 4.36-4.86) were preceded by preoperative corticosteroid use and 1469 (5.52%; 95% CI, 5.24-5.79) were followed by postoperative infections. In a propensity score analysis controlling for comorbidities, illness severity, and preexisting preoperative infections, corticosteroid use was independently associated with subsequent postoperative infections (odds ratio, 1.38; 95% CI, 1.11-1.70). Our results were unchanged in sensitivity analyses controlling for central nervous system tumors or active treatment with chemotherapy. Conclusion: Our results suggest that preoperative corticosteroid use is associated with an increased risk of infectious complications after neurosurgery. These findings may aid physicians with preoperative treatment decisions and risk stratification. Future randomized trials are needed to guide preoperative use of corticosteroids in this population. PMID:24707336

  9. Preoperative platelet transfusions and perioperative red blood cell requirements in patients with thrombocytopenia undergoing noncardiac surgery

    PubMed Central

    Warner, Matthew A.; Jia, Qing; Clifford, Leanne; Wilson, Gregory; Brown, Michael J.; Hanson, Andrew C.; Schroeder, Darrell R.; Kor, Daryl J.

    2016-01-01

    BACKGROUND Perioperative hemorrhage impacts patient outcomes and health care resource utilization, yet the risks of transfusion therapies are significant. In patients with preoperative thrombocytopenia, the effects of prophylactic preoperative platelet (PLT) transfusion on perioperative bleeding complications remain uncertain. STUDY DESIGN AND METHODS This is a retrospective cohort study of noncardiac surgical patients between January 1, 2008, and December 31, 2011. Propensity-adjusted analyses were used to evaluate associations between preoperative thrombocytopenia, preoperative PLT transfusion, and the outcomes of interest, with a primary outcome of perioperative red blood cell (RBC) transfusion. RESULTS A total of 13,978 study participants were included; 860 (6.2%) had a PLT count of not more than 100 × 109/L with 71 (8.3%) receiving PLTs preoperatively. Administration of PLTs was associated with higher rates of perioperative RBC transfusion (66.2% vs. 49.1%, p 0.0065); however, in propensity-adjusted analysis there was no significant difference between groups (odds ratio [OR] [95% confidence interval {95% CI}], 1.68 [0.95–2.99]; p =0.0764]. Patients receiving PLTs had higher rates of intensive care unit (ICU) admission (OR [95% CI], 1.95 [1.10–3.46]; p =0.0224) and longer hospital lengths of stay (estimate [95% bootstrap CI], 7.2 [0.8–13.9] days; p =0.0006) in propensity-adjusted analyses. CONCLUSION Preoperative PLT transfusion did not attenuate RBC requirements in patients with thrombocytopenia undergoing noncardiac surgery. Moreover, preoperative PLT transfusion was associated with increased ICU admission rates and hospital duration. These findings suggest that more conservative management of preoperative thrombocytopenia may be warranted. PMID:26559936

  10. Preoperative Nutritional Status and The Impact on Radical Cystectomy Recovery: An International Comparative Study.

    PubMed

    Jensen, Bente Thoft; Dalbagni, Guido; Borre, Michael; Love-Retinger, Nora

    2016-01-01

    In radical cystectomy, under-nutrition is common and has detrimental physiological and clinical effects, which can lead to increased complications and prolonged recovery. This article compares measurements and outcomes across continents in this patient population with advanced bladder cancer. The association of preoperative nutritional risk, nutritional status, and length of stay is equal across continents, and the results promote increased clinical awareness that women at severe risk should be identified preoperatively. PMID:27501594

  11. Preoperative hypnotherapy in the management of a child with anticipatory nausea and vomiting.

    PubMed

    Mackenzie, A; Frawley, G P

    2007-10-01

    A six-year-old boy with oesophageal strictures secondary to neonatal repair of oesophageal atresia and requiring six to eight weekly oesophageal dilatations by bouginage developed anticipatory nausea and vomiting. This was effectively managed by a course of preoperative hypnotherapy over four sessions. Resolution of anticipatory nausea and vomiting occurred along with cessation of postoperative nausea and vomiting. This case supports early intervention with preoperative hypnotherapy in children with anticipatory nausea and vomiting that has not responded to other measures. PMID:17933170

  12. Breast volumetric analysis for aesthetic planning in breast reconstruction: a literature review of techniques

    PubMed Central

    Rozen, Warren Matthew; Spychal, Robert T.; Hunter-Smith, David J.

    2016-01-01

    Background Accurate volumetric analysis is an essential component of preoperative planning in both reconstructive and aesthetic breast procedures towards achieving symmetrization and patient-satisfactory outcome. Numerous comparative studies and reviews of individual techniques have been reported. However, a unifying review of all techniques comparing their accuracy, reliability, and practicality has been lacking. Methods A review of the published English literature dating from 1950 to 2015 using databases, such as PubMed, Medline, Web of Science, and EMBASE, was undertaken. Results Since Bouman’s first description of water displacement method, a range of volumetric assessment techniques have been described: thermoplastic casting, direct anthropomorphic measurement, two-dimensional (2D) imaging, and computed tomography (CT)/magnetic resonance imaging (MRI) scans. However, most have been unreliable, difficult to execute and demonstrate limited practicability. Introduction of 3D surface imaging has revolutionized the field due to its ease of use, fast speed, accuracy, and reliability. However, its widespread use has been limited by its high cost and lack of high level of evidence. Recent developments have unveiled the first web-based 3D surface imaging program, 4D imaging, and 3D printing. Conclusions Despite its importance, an accurate, reliable, and simple breast volumetric analysis tool has been elusive until the introduction of 3D surface imaging technology. However, its high cost has limited its wide usage. Novel adjunct technologies, such as web-based 3D surface imaging program, 4D imaging, and 3D printing, appear promising. PMID:27047788

  13. Near-facility environmental monitoring quality assurance project plan

    SciTech Connect

    McKinney, S.M.

    1997-11-24

    This Quality Assurance Project Plan addresses the quality assurance requirements for the activities associated with the preoperational and near facility environmental monitoring performed by Waste Management Federal Services, Inc., Northwest Operations and supersedes WHC-EP-0538-2. This plan applies to all sampling and monitoring activities performed by waste management Federal Services, Inc., Northwest Operations in implementing facility environmental monitoring at the Hanford Site.

  14. Efficacy of Acupuncture in Reducing Preoperative Anxiety: A Meta-Analysis

    PubMed Central

    Bae, Hyojeong; Bae, Hyunsu; Min, Byung-Il; Cho, Seunghun

    2014-01-01

    Background. Acupuncture has been shown to reduce preoperative anxiety in several previous randomized controlled trials (RCTs). In order to assess the preoperative anxiolytic efficacy of acupuncture therapy, this study conducted a meta-analysis of an array of appropriate studies. Methods. Four electronic databases (MEDLINE, EMBASE, CENTRAL, and CINAHL) were searched up to February 2014. In the meta-analysis data were included from RCT studies in which groups receiving preoperative acupuncture treatment were compared with control groups receiving a placebo for anxiety. Results. Fourteen publications (N = 1,034) were included. Six publications, using the State-Trait Anxiety Inventory-State (STAI-S), reported that acupuncture interventions led to greater reductions in preoperative anxiety relative to sham acupuncture (mean difference = 5.63, P < .00001, 95% CI [4.14, 7.11]). Further eight publications, employing visual analogue scales (VAS), also indicated significant differences in preoperative anxiety amelioration between acupuncture and sham acupuncture (mean difference = 19.23, P < .00001, 95% CI [16.34, 22.12]). Conclusions. Acupuncture therapy aiming at reducing preoperative anxiety has a statistically significant effect relative to placebo or nontreatment conditions. Well-designed and rigorous studies that employ large sample sizes are necessary to corroborate this finding. PMID:25254059

  15. Preoperative drainage for malignant biliary strictures: is it time for self-expanding metallic stents?

    PubMed

    Roque, Jason; Ho, Shiaw-Hooi; Goh, Khean-Lee

    2015-01-01

    Palliation of jaundice improves the general health of the patient and, therefore, surgical outcomes. Because of the complexity and location of strictures, especially proximally, drainage has been accompanied by increased morbidity due to sepsis. Another concern is the provocation of an inflammatory and fibrotic reaction around the area of stent placement. Preoperative biliary drainage with self-expanding metallic stent (SEMS) insertion can be achieved via a percutaneous method or through endoscopic retrograde cholangiopancreatography. A recently published multicenter randomized Dutch study has shown increased morbidity with preoperative biliary drainage. A Cochrane meta-analysis has also shown a significantly increased complication rate with preoperative drainage. However, few of these studies have used a SEMS, which allows better biliary drainage. No randomized controlled trials have compared preoperative deployment of SEMS versus conventional plastic stents. The outcomes of biliary drainage also depend on the location of the obstruction, namely the difficulty with proximal compared to distal strictures. Pathophysiologically, palliation of jaundice will benefit all patients awaiting surgery. However, preoperative drainage often results in increased morbidity because of procedure-related sepsis. The use of SEMS may change the outcome of preoperative biliary drainage dramatically. PMID:25674520

  16. The unfavorable nature of preoperative delirium in elderly hip fractured patients.

    PubMed

    Adunsky, Abraham; Levy, Rami; Heim, Michael; Mizrahi, Eliyahu; Arad, M

    2003-01-01

    The onset of delirium is frequent in elderly patients who sustain hip fractures. The purpose of this study was to characterize different patterns of preoperative and postoperative delirium, to study factors associated with preoperative delirium and to evaluate the possible different outcome of these patients. This retrospective study comprised 281 elderly patients with hip fractures undergoing surgical fixation. Data collection included age, sex, length of stay, type of fracture, cognitive status by mini mental state examination (MMSE), assessment of possible delirium by the confusion assessment method (CAM) and functional outcome assessed by functional independence measure (FIM). A database search was conducted to identify whether delirium onset occurred prior to or following surgery. About 31% of the total sample developed delirium. Delirious patients tended to be more disabled (P = 0.03) and cognitively impaired (P = 0.018), compared with non-delirious patients. Most delirious cases (53%) had their onset in the preoperative period. Patients with preoperative delirium were older (P = 0.03), had a lower prefracture mobility (P < 0.01), impaired cognition (P = 0.04) and showed an adverse functional outcome in terms of FIM score. Regression analysis showed that prefracture dementia, prefracture mobility and low MMSE scores were strongly associated with higher probability of having preoperative delirium, with no additional effect of other variables. It is concluded that preoperative delirium should be viewed as a separate entity with unfavorable nature and adverse outcome. Careful preventive measures and better treating strategies should be employed to avoid this clinical condition. PMID:12849100

  17. Transthoracic echocardiography may be useful for preoperative cardiac evaluation of gynaecological patients undergoing routine surgery.

    PubMed

    Shrestha, B; Pradhan, P; Shakya, G R; Giri, A; Regmi, R; Dhungel, S

    2012-12-01

    Echocardiography has been an integral noninvasive tool for [preoperative] cardiac evaluation that provides with echocardiographic details which may also be useful to perioperative clinicians to tailor their anesthetic deliberation while dealing with preoperative patients. The objective of this study is preoperative evaluation of routine gynecological patients echocardiographically after being referred from respective internists or anesthesiologists. This was a prospective, nonrandomized study of elective 68 cases who underwent echocardiographic evaluation preoperatively from 15th July 2009 to 14th July 2012. The mean age of the patients was 52.1 +/- 10.3 years with the age range of 30-79 years. Valvular heart disease was the most common echocardiographic finding (129.4%) followed by left ventricular diastolic dysfunction, LVDD (48.5%) and left ventricular hypertrophy (22.1%). Systolic dysfunction was detected in 2.9% of patients and pulmonary arterial hypertension in 2.9% patients. Amongst patients referred after preoperative anaesthetic evaluation, patients had different cardiac lesions echocardiographically. Preoperative echocardiographic evaluation may provide important cardiac informations and values which might be employed by perioperative physicians to tailor their treatment. PMID:24579536

  18. Maxillary fixed prosthesis design based on the preoperative physical examination.

    PubMed

    Block, Michael S

    2015-05-01

    The purpose of this article is to illustrate the use of physical examination findings that can be used to determine the design characteristics of a full arch restoration in the maxilla. These anatomic findings include 1) the resting and 2) smile line exposures of the central incisor; 3) the vertical position of the edentulous ridge when smiling; 4) the anteroposterior relation of the teeth to the edentulous ridge; 5) the presence of bone posterior to the premolar region; 6) the anterior height of the alveolar bone in relation to the floor of the nose; and 7) the planned inclination of the maxillary teeth. Based on these physical findings, the final prosthetic plan can be established before surgery. Determination of the final restorative plan determines the surgical procedures to be performed. PMID:25659360

  19. Feedback about More Accurate versus Less Accurate Trials: Differential Effects on Self-Confidence and Activation

    ERIC Educational Resources Information Center

    Badami, Rokhsareh; VaezMousavi, Mohammad; Wulf, Gabriele; Namazizadeh, Mahdi

    2012-01-01

    One purpose of the present study was to examine whether self-confidence or anxiety would be differentially affected by feedback from more accurate rather than less accurate trials. The second purpose was to determine whether arousal variations (activation) would predict performance. On Day 1, participants performed a golf putting task under one of…

  20. Preoperational Subsurface Conditions at the Idaho Nuclear Technology and Engineering Center Service Wastewater Discharge Facility

    SciTech Connect

    Ansley, Shannon L.

    2002-02-20

    The Idaho Nuclear Technology and Engineering Center (INTEC) Service Wastewater Discharge Facility replaces the existing percolation ponds as a disposal facility for the INTEC Service Waste Stream. A preferred alternative for helping decrease water content in the subsurface near INTEC, closure of the existing ponds is required by the INTEC Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Record of Decision (ROD) for Waste Area Group 3 Operable Unit 3-13 (DOE-ID 1999a). By August 2002, the replacement facility was constructed approximately 2 miles southwest of INTEC, near the Big Lost River channel. Because groundwater beneath the Idaho National Engineering and Environmental Laboratory (INEEL) is protected under Federal and State of Idaho regulations from degradation due to INEEL activities, preoperational data required by U.S. Department of Energy (DOE) Order 5400.1 were collected. These data include preexisting physical, chemical, and biological conditions that could be affected by the discharge; background levels of radioactive and chemical components; pertinent environmental and ecological parameters; and potential pathways for human exposure or environmental impact. This document presents specific data collected in support of DOE Order 5400.1, including: four quarters of groundwater sampling and analysis of chemical and radiological parameters; general facility description; site specific geology, stratigraphy, soils, and hydrology; perched water discussions; and general regulatory requirements. However, in order to avoid duplication of previous information, the reader is directed to other referenced publications for more detailed information. Documents that are not readily available are compiled in this publication as appendices. These documents include well and borehole completion reports, a perched water evaluation letter report, the draft INEEL Wellhead Protection Program Plan, and the Environmental Checklist.

  1. Preoperational Subsurface Conditions at the Idaho Nuclear Technology and Engineering Center Service Waste Disposal Facility

    SciTech Connect

    Ansley, Shannon Leigh

    2002-02-01

    The Idaho Nuclear Technology and Engineering Center (INTEC) Service Wastewater Discharge Facility replaces the existing percolation ponds as a disposal facility for the INTEC Service Waste Stream. A preferred alternative for helping decrease water content in the subsurface near INTEC, closure of the existing ponds is required by the INTEC Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Record of Decision (ROD) for Waste Area Group 3 Operable Unit 3-13 (DOE-ID 1999a). By August 2002, the replacement facility was constructed approximately 2 miles southwest of INTEC, near the Big Lost River channel. Because groundwater beneath the Idaho National Engineering and Environmental Laboratory (INEEL) is protected under Federal and State of Idaho regulations from degradation due to INEEL activities, preoperational data required by U.S. Department of Energy (DOE) Order 5400.1 were collected. These data include preexisting physical, chemical, and biological conditions that could be affected by the discharge; background levels of radioactive and chemical components; pertinent environmental and ecological parameters; and potential pathways for human exposure or environmental impact. This document presents specific data collected in support of DOE Order 5400.1, including: four quarters of groundwater sampling and analysis of chemical and radiological parameters; general facility description; site specific geology, stratigraphy, soils, and hydrology; perched water discussions; and general regulatory requirements. However, in order to avoid duplication of previous information, the reader is directed to other referenced publications for more detailed information. Documents that are not readily available are compiled in this publication as appendices. These documents include well and borehole completion reports, a perched water evaluation letter report, the draft INEEL Wellhead Protection Program Plan, and the Environmental Checklist.

  2. Preoperative Portal Vein Embolization Tailored to Prepare the Liver for Complex Resections: Initial Experience

    SciTech Connect

    Baere, T. de Robinson, J. M.; Deschamps, F.; Rao, P.; Teriitheau, C.; Goere, D.; Elias, D.

    2010-10-15

    The purpose of this study was to evaluate the safety and efficacy of preoperative portal vein embolization (PVE) tailored to prepare the liver for complex and extended resections. During the past 5 years, 12 PVEs were performed in noncirrhotic patients with liver metastases from colon cancer (n = 10), choroidal melanoma (n = 1), and leiomyosarcoma (n = 1) to prepare complex anatomical liver resections in patients with small future remnant livers. These liver resections planned to preserve only segment IV in four patients, segments IV, V, and VIII in four patients, segments II, III, VI, and VII in three patients, and segments V and VI in one patient. PVE was performed under general anesthesia with a flow-guided injection of a mixture of cyanoacrylate and Lipiodol using a 5-Fr catheter. All portal branches feeding the liver segments to be resected were successfully embolized with cyanoacrylate except one, which was occluded with coils due to the risk of reflux with cyanoacrylate. After a mean of 32 days, CT volumetry revealed a mean hypertrophy of the unembolized liver of 47 {+-} 25% (range, 21-88%). Liver resections could be performed in 10 patients but were canceled in 2, due to the occurrence of a new hepatic tumor in one and an insufficiently increased volume in the other. Among the 10 patients who underwent the liver resection, 1 died of postoperative sepsis, 3 died 3 to 32 months after surgery, including 1 death unrelated to cancer, and 6 were alive after 6 to 36 months after surgery. In conclusion, in this preliminary report, PVE appears to be feasible and able to induce hypertrophy of the future remnant liver before a complex and extended hepatectomy. Further evaluation is needed in a larger cohort.

  3. Impact of a preoperative evaluation on the outcomes of an arteriovenous fistula

    PubMed Central

    Kim, Sung Min; Han, Youngjin; Kwon, Hyunwook; Hong, Hee Sun; Choi, Ji Yoon; Park, Hojong; Kwon, Tae-Won

    2016-01-01

    Purpose The aim of this study was to determine the possible predictors of primary arteriovenous fistula (AVF) failure and examine the impact of a preoperative evaluation on AVF outcomes. Methods A total of 539 patients who underwent assessment for a suitable site for AVF creation by physical examination alone or additional duplex ultrasound were included in this study. Demographics, patient characteristics, and AVF outcomes were analyzed retrospectively. Results AVF creation was proposed in 469 patients (87.0%) according to physical examination alone (351 patients) or additional duplex ultrasound (118 patients); a prosthetic arteriovenous graft was initially placed in the remaining 70 patients (13.0%). Although the primary failure rate was significantly higher in patients assessed by duplex ultrasound (P = 0.001), ultrasound information changed the clinical plan, increasing AVF use for dialysis, in 92 of the 188 patients (48.9%) with an insufficient physical examination. Female sex and diabetes mellitus were risk factors significantly associated with primary AVF failure. Because of different inclusion criteria and a lack of adjustment for baseline differences, Kaplan-Meier survival analysis showed better AVF outcomes in patients assessed by physical examination alone; an insufficient physical examination was the only risk factor significantly associated with AVF outcomes. Conclusion Routine use of duplex ultrasound is not necessary in chronic kidney disease patients with a satisfactory physical examination. Given that female gender and diabetes mellitus are significantly associated with primary AVF failure, duplex ultrasound could be of particular benefit in these subtypes of patients without a sufficient physical examination. PMID:27073794

  4. Feedback about more accurate versus less accurate trials: differential effects on self-confidence and activation.

    PubMed

    Badami, Rokhsareh; VaezMousavi, Mohammad; Wulf, Gabriele; Namazizadeh, Mahdi

    2012-06-01

    One purpose of the present study was to examine whether self-confidence or anxiety would be differentially affected byfeedback from more accurate rather than less accurate trials. The second purpose was to determine whether arousal variations (activation) would predict performance. On day 1, participants performed a golf putting task under one of two conditions: one group received feedback on the most accurate trials, whereas another group received feedback on the least accurate trials. On day 2, participants completed an anxiety questionnaire and performed a retention test. Shin conductance level, as a measure of arousal, was determined. The results indicated that feedback about more accurate trials resulted in more effective learning as well as increased self-confidence. Also, activation was a predictor of performance. PMID:22808705

  5. Adaptive script based animations for intervention planning.

    PubMed

    Muehler, Konrad; Bade, Ragnar; Preim, Bernhard

    2006-01-01

    We describe scripting facilities to create medical animations for intervention planning based on medical volume data and derived segmentation information. A data independent scripting language has been developed to separate animation scripts from imaging data. The scripting facilities are adaptive and allow to reuse one script to create animations for many different patients. With expressive animations, we support the individual planning process, the preoperative documentation as well as discussions between medical doctors, for example in a tumor board. We also discuss the enhancement of interactive explorations with animations generated on the fly. PMID:17354925

  6. New model accurately predicts reformate composition

    SciTech Connect

    Ancheyta-Juarez, J.; Aguilar-Rodriguez, E. )

    1994-01-31

    Although naphtha reforming is a well-known process, the evolution of catalyst formulation, as well as new trends in gasoline specifications, have led to rapid evolution of the process, including: reactor design, regeneration mode, and operating conditions. Mathematical modeling of the reforming process is an increasingly important tool. It is fundamental to the proper design of new reactors and revamp of existing ones. Modeling can be used to optimize operating conditions, analyze the effects of process variables, and enhance unit performance. Instituto Mexicano del Petroleo has developed a model of the catalytic reforming process that accurately predicts reformate composition at the higher-severity conditions at which new reformers are being designed. The new AA model is more accurate than previous proposals because it takes into account the effects of temperature and pressure on the rate constants of each chemical reaction.

  7. Accurate colorimetric feedback for RGB LED clusters

    NASA Astrophysics Data System (ADS)

    Man, Kwong; Ashdown, Ian

    2006-08-01

    We present an empirical model of LED emission spectra that is applicable to both InGaN and AlInGaP high-flux LEDs, and which accurately predicts their relative spectral power distributions over a wide range of LED junction temperatures. We further demonstrate with laboratory measurements that changes in LED spectral power distribution with temperature can be accurately predicted with first- or second-order equations. This provides the basis for a real-time colorimetric feedback system for RGB LED clusters that can maintain the chromaticity of white light at constant intensity to within +/-0.003 Δuv over a range of 45 degrees Celsius, and to within 0.01 Δuv when dimmed over an intensity range of 10:1.

  8. Accurate mask model for advanced nodes

    NASA Astrophysics Data System (ADS)

    Zine El Abidine, Nacer; Sundermann, Frank; Yesilada, Emek; Ndiaye, El Hadji Omar; Mishra, Kushlendra; Paninjath, Sankaranarayanan; Bork, Ingo; Buck, Peter; Toublan, Olivier; Schanen, Isabelle

    2014-07-01

    Standard OPC models consist of a physical optical model and an empirical resist model. The resist model compensates the optical model imprecision on top of modeling resist development. The optical model imprecision may result from mask topography effects and real mask information including mask ebeam writing and mask process contributions. For advanced technology nodes, significant progress has been made to model mask topography to improve optical model accuracy. However, mask information is difficult to decorrelate from standard OPC model. Our goal is to establish an accurate mask model through a dedicated calibration exercise. In this paper, we present a flow to calibrate an accurate mask enabling its implementation. The study covers the different effects that should be embedded in the mask model as well as the experiment required to model them.

  9. Accurate guitar tuning by cochlear implant musicians.

    PubMed

    Lu, Thomas; Huang, Juan; Zeng, Fan-Gang

    2014-01-01

    Modern cochlear implant (CI) users understand speech but find difficulty in music appreciation due to poor pitch perception. Still, some deaf musicians continue to perform with their CI. Here we show unexpected results that CI musicians can reliably tune a guitar by CI alone and, under controlled conditions, match simultaneously presented tones to <0.5 Hz. One subject had normal contralateral hearing and produced more accurate tuning with CI than his normal ear. To understand these counterintuitive findings, we presented tones sequentially and found that tuning error was larger at ∼ 30 Hz for both subjects. A third subject, a non-musician CI user with normal contralateral hearing, showed similar trends in performance between CI and normal hearing ears but with less precision. This difference, along with electric analysis, showed that accurate tuning was achieved by listening to beats rather than discriminating pitch, effectively turning a spectral task into a temporal discrimination task. PMID:24651081

  10. Two highly accurate methods for pitch calibration

    NASA Astrophysics Data System (ADS)

    Kniel, K.; Härtig, F.; Osawa, S.; Sato, O.

    2009-11-01

    Among profiles, helix and tooth thickness pitch is one of the most important parameters of an involute gear measurement evaluation. In principle, coordinate measuring machines (CMM) and CNC-controlled gear measuring machines as a variant of a CMM are suited for these kinds of gear measurements. Now the Japan National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) and the German national metrology institute the Physikalisch-Technische Bundesanstalt (PTB) have each developed independently highly accurate pitch calibration methods applicable to CMM or gear measuring machines. Both calibration methods are based on the so-called closure technique which allows the separation of the systematic errors of the measurement device and the errors of the gear. For the verification of both calibration methods, NMIJ/AIST and PTB performed measurements on a specially designed pitch artifact. The comparison of the results shows that both methods can be used for highly accurate calibrations of pitch standards.

  11. Accurate modeling of parallel scientific computations

    NASA Technical Reports Server (NTRS)

    Nicol, David M.; Townsend, James C.

    1988-01-01

    Scientific codes are usually parallelized by partitioning a grid among processors. To achieve top performance it is necessary to partition the grid so as to balance workload and minimize communication/synchronization costs. This problem is particularly acute when the grid is irregular, changes over the course of the computation, and is not known until load time. Critical mapping and remapping decisions rest on the ability to accurately predict performance, given a description of a grid and its partition. This paper discusses one approach to this problem, and illustrates its use on a one-dimensional fluids code. The models constructed are shown to be accurate, and are used to find optimal remapping schedules.

  12. Accurate Guitar Tuning by Cochlear Implant Musicians

    PubMed Central

    Lu, Thomas; Huang, Juan; Zeng, Fan-Gang

    2014-01-01

    Modern cochlear implant (CI) users understand speech but find difficulty in music appreciation due to poor pitch perception. Still, some deaf musicians continue to perform with their CI. Here we show unexpected results that CI musicians can reliably tune a guitar by CI alone and, under controlled conditions, match simultaneously presented tones to <0.5 Hz. One subject had normal contralateral hearing and produced more accurate tuning with CI than his normal ear. To understand these counterintuitive findings, we presented tones sequentially and found that tuning error was larger at ∼30 Hz for both subjects. A third subject, a non-musician CI user with normal contralateral hearing, showed similar trends in performance between CI and normal hearing ears but with less precision. This difference, along with electric analysis, showed that accurate tuning was achieved by listening to beats rather than discriminating pitch, effectively turning a spectral task into a temporal discrimination task. PMID:24651081

  13. An accurate registration technique for distorted images

    NASA Technical Reports Server (NTRS)

    Delapena, Michele; Shaw, Richard A.; Linde, Peter; Dravins, Dainis

    1990-01-01

    Accurate registration of International Ultraviolet Explorer (IUE) images is crucial because the variability of the geometrical distortions that are introduced by the SEC-Vidicon cameras ensures that raw science images are never perfectly aligned with the Intensity Transfer Functions (ITFs) (i.e., graded floodlamp exposures that are used to linearize and normalize the camera response). A technique for precisely registering IUE images which uses a cross correlation of the fixed pattern that exists in all raw IUE images is described.

  14. Accurate maser positions for MALT-45

    NASA Astrophysics Data System (ADS)

    Jordan, Christopher; Bains, Indra; Voronkov, Maxim; Lo, Nadia; Jones, Paul; Muller, Erik; Cunningham, Maria; Burton, Michael; Brooks, Kate; Green, James; Fuller, Gary; Barnes, Peter; Ellingsen, Simon; Urquhart, James; Morgan, Larry; Rowell, Gavin; Walsh, Andrew; Loenen, Edo; Baan, Willem; Hill, Tracey; Purcell, Cormac; Breen, Shari; Peretto, Nicolas; Jackson, James; Lowe, Vicki; Longmore, Steven

    2013-10-01

    MALT-45 is an untargeted survey, mapping the Galactic plane in CS (1-0), Class I methanol masers, SiO masers and thermal emission, and high frequency continuum emission. After obtaining images from the survey, a number of masers were detected, but without accurate positions. This project seeks to resolve each maser and its environment, with the ultimate goal of placing the Class I methanol maser into a timeline of high mass star formation.

  15. Accurate phase-shift velocimetry in rock.

    PubMed

    Shukla, Matsyendra Nath; Vallatos, Antoine; Phoenix, Vernon R; Holmes, William M

    2016-06-01

    Spatially resolved Pulsed Field Gradient (PFG) velocimetry techniques can provide precious information concerning flow through opaque systems, including rocks. This velocimetry data is used to enhance flow models in a wide range of systems, from oil behaviour in reservoir rocks to contaminant transport in aquifers. Phase-shift velocimetry is the fastest way to produce velocity maps but critical issues have been reported when studying flow through rocks and porous media, leading to inaccurate results. Combining PFG measurements for flow through Bentheimer sandstone with simulations, we demonstrate that asymmetries in the molecular displacement distributions within each voxel are the main source of phase-shift velocimetry errors. We show that when flow-related average molecular displacements are negligible compared to self-diffusion ones, symmetric displacement distributions can be obtained while phase measurement noise is minimised. We elaborate a complete method for the production of accurate phase-shift velocimetry maps in rocks and low porosity media and demonstrate its validity for a range of flow rates. This development of accurate phase-shift velocimetry now enables more rapid and accurate velocity analysis, potentially helping to inform both industrial applications and theoretical models. PMID:27111139

  16. Accurate Molecular Polarizabilities Based on Continuum Electrostatics

    PubMed Central

    Truchon, Jean-François; Nicholls, Anthony; Iftimie, Radu I.; Roux, Benoît; Bayly, Christopher I.

    2013-01-01

    A novel approach for representing the intramolecular polarizability as a continuum dielectric is introduced to account for molecular electronic polarization. It is shown, using a finite-difference solution to the Poisson equation, that the Electronic Polarization from Internal Continuum (EPIC) model yields accurate gas-phase molecular polarizability tensors for a test set of 98 challenging molecules composed of heteroaromatics, alkanes and diatomics. The electronic polarization originates from a high intramolecular dielectric that produces polarizabilities consistent with B3LYP/aug-cc-pVTZ and experimental values when surrounded by vacuum dielectric. In contrast to other approaches to model electronic polarization, this simple model avoids the polarizability catastrophe and accurately calculates molecular anisotropy with the use of very few fitted parameters and without resorting to auxiliary sites or anisotropic atomic centers. On average, the unsigned error in the average polarizability and anisotropy compared to B3LYP are 2% and 5%, respectively. The correlation between the polarizability components from B3LYP and this approach lead to a R2 of 0.990 and a slope of 0.999. Even the F2 anisotropy, shown to be a difficult case for existing polarizability models, can be reproduced within 2% error. In addition to providing new parameters for a rapid method directly applicable to the calculation of polarizabilities, this work extends the widely used Poisson equation to areas where accurate molecular polarizabilities matter. PMID:23646034

  17. Accurate phase-shift velocimetry in rock

    NASA Astrophysics Data System (ADS)

    Shukla, Matsyendra Nath; Vallatos, Antoine; Phoenix, Vernon R.; Holmes, William M.

    2016-06-01

    Spatially resolved Pulsed Field Gradient (PFG) velocimetry techniques can provide precious information concerning flow through opaque systems, including rocks. This velocimetry data is used to enhance flow models in a wide range of systems, from oil behaviour in reservoir rocks to contaminant transport in aquifers. Phase-shift velocimetry is the fastest way to produce velocity maps but critical issues have been reported when studying flow through rocks and porous media, leading to inaccurate results. Combining PFG measurements for flow through Bentheimer sandstone with simulations, we demonstrate that asymmetries in the molecular displacement distributions within each voxel are the main source of phase-shift velocimetry errors. We show that when flow-related average molecular displacements are negligible compared to self-diffusion ones, symmetric displacement distributions can be obtained while phase measurement noise is minimised. We elaborate a complete method for the production of accurate phase-shift velocimetry maps in rocks and low porosity media and demonstrate its validity for a range of flow rates. This development of accurate phase-shift velocimetry now enables more rapid and accurate velocity analysis, potentially helping to inform both industrial applications and theoretical models.

  18. Preoperative airway assessment - experience gained from a multicentre cluster randomised trial and the Danish Anaesthesia Database.

    PubMed

    Nørskov, Anders Kehlet

    2016-05-01

    and mask ventilation. Papers 2 and 3 outline the methodology and the pre-trial calculations and considerations leading to the DIFFICAIR trial described in Paper 4. The trial was designed to randomise anaesthesia department to either thorough education in, and subsequent use of the SARI for preoperative airway assessment or to continue usual care. Registration of the SARI in DAD was made mandatory in SARI departments and impossible in usual care departments. Conditions regarding anticipation of difficulties and actual airway managements were recorded as for Paper 1. DAD data made it possible to estimate an appropriate sample size, considering the between cluster variation, and to construct a stratification variable based on 2011 baseline values of the primary outcome used in the DIFFICAIR trial. Paper 1 revealed that 1.86% of all patients who were intubated, but not planned for advanced intubation techniques (e.g. video laryngoscopy), were unanticipated difficult to intubate. However, 75 to 93% of all difficult intubations were unanticipated. Furthermore, 94% of all difficult mask ventilations were unanticipated. In Paper 4, 59,514 patients were included in the primary analyses. The proportion of unanticipated difficult intubations was 2.38% (696/29,209) in SARI departments and 2.39% (723/30,305) in usual care departments. The adjusted odds ratio was 1.03 (95% CI: 0.77-1.38), p = 0.84. No significant differences were detected in other adjusted outcome measures and neither a 58% increase in patients anticipated to have intubation difficulties nor an 84% increase in patients scheduled for advanced intubation techniques in SARI departments reached statistical significance, p = 0.29 and p = 0.06 respectively. The papers constituting this thesis demonstrate that at high proportion of airway management difficulties are unanticipated. In a cluster randomised trial it was not possible to reduce the proportion of unanticipated difficult intubation in daily clinical practice by

  19. Sagittal synostosis: I. Preoperative morphology of the skull.

    PubMed

    Guimarães-Ferreira, José; Gewalli, Fredrik; David, Lisa; Darvann, Tron A; Hermann, Nuno V; Kreiborg, Sven; Friede, Hans; Lauritzen, Claes G K

    2006-01-01

    The aim of this study was to characterise the preoperative morphology of the skull in sagittal synostosis in an objective and quantified way. The shapes of the skulls of 105 patients with isolated premature synostosis of the sagittal suture (SS group) were studied and compared with those of a control group of 72 children with unilateral incomplete cleft lip (UICL). A standardised radiocephalometric technique was used to obtain the images. A modification of a method developed by Kreiborg was used to analyse the radiocephalograms, which included the digitisation of 88 landmarks in the calvaria, skull base, and orbit (42 in the lateral and 46 in the frontal projections), the production of plots of mean shape for each group, and the intergroup comparison of a series of 81 variables (linear distance between selected landmarks, and angles defined by groups of three landmarks). Data from a subgroup of 66 patients aged 5 to 8 months were further compared to age-matched normative data in terms of seven angular and linear calvarial, cranial base and orbital variables. In a comparative analysis of the mean lateral plots, the foreheads of the study group (SS) had a more pronounced anterior slope and were also more convex. The vertex area was located more anteriorly, and was less convex. The occipital curvature was more prominent. Analysis of the mean frontal plots revealed a lack in convexity and lateral projection of the upper parietal regions, as well as a lower location of the line of maximum skull width. Comparison of the mean values of an SS subgroup to age-matched normative data showed a longer (p<0.001) and narrower skull (p<0.001) and a greater interorbital distance (p<0.001). The cranial base angle, the sella to nasion, and sella to basion lengths did not differ significantly. Sagittal synostosis is characterised by an extensive deformity of the cranial vault, with an essentially normal cranial base. The widened interorbital distance is probably related to

  20. Improving patient flow in pre-operative assessment

    PubMed Central

    Stark, Cameron; Gent, Anne; Kirkland, Linda

    2015-01-01

    Annual patient attendances at a pre-operative assessment department increased by 24.8% from 5659 in 2009, to 7062 in 2012. The unit was staffed by administrative staff, nurses, and health care assistants (HCA). Medical review was accessed via on call medical staff, or notes were sent to anaesthetists for further review. With rising demand, patient waits increased. The average lead time for a patient (time from entering the department to leaving) was 79 minutes. 9.3% of patients attended within two weeks of their scheduled surgery date. 10% of patients were asked to return on a later day, as there was not sufficient capacity to undertake their assessment. There were nine routes of referral in to the department. Patients moved between different clinic rooms and the waiting area several times. Work patterns were uneven, as many attendances were from out-patient clinics which meant peak attendance times were linked to clinic times. There were substantial differences in the approaches of different nurses, making the HCA role difficult. Patients reported dissatisfaction with waits. Using a Lean quality improvement process with rapid PDSA cycles, the service changed to one in which patients were placed in a room, and remained there for the duration of their assessment. Standard work was developed for HCWs and nurses. Rooms were standardised using 5S processes, and set up improved to reduce time spent looking for supplies. A co-ordinator role was introduced using existing staff to monitor flow and to organise the required medical assessments and ECGs. Timing of booked appointments were altered to take account of clinic times. Routes in to the department were reduced from nine to one. Ten months after the work began, the average lead time had reduced to 59 minutes. The proportion of people attending within two weeks of their surgery decreased from 9.3% to 5.3%. Referrals for an anaesthetic opinion decreased from 30% to 20%, and in the month reviewed no one had to return to

  1. Preoperative Preparation and Patient Selection for Cytoreductive Surgery and HIPEC.

    PubMed

    Ashvin, Rangole; Nikhilesh, Jain

    2016-06-01

    . Patients undergoing HIPEC surgery face the usual physiological insults of a major surgery in addition to the thermal stress secondary to intraperitoneal administration of heated chemotherapy agent. A team approach of everyone involved in care of these patients is known to improve patient outcomes. It has also been observed that with the necessary preoperative & perioperative steps, the morbidity and mortality for this treatment can be brought down as comparable to any other major abdominal surgeries. PMID:27065711

  2. Improving patient flow in pre-operative assessment.

    PubMed

    Stark, Cameron; Gent, Anne; Kirkland, Linda

    2015-01-01

    Annual patient attendances at a pre-operative assessment department increased by 24.8% from 5659 in 2009, to 7062 in 2012. The unit was staffed by administrative staff, nurses, and health care assistants (HCA). Medical review was accessed via on call medical staff, or notes were sent to anaesthetists for further review. With rising demand, patient waits increased. The average lead time for a patient (time from entering the department to leaving) was 79 minutes. 9.3% of patients attended within two weeks of their scheduled surgery date. 10% of patients were asked to return on a later day, as there was not sufficient capacity to undertake their assessment. There were nine routes of referral in to the department. Patients moved between different clinic rooms and the waiting area several times. Work patterns were uneven, as many attendances were from out-patient clinics which meant peak attendance times were linked to clinic times. There were substantial differences in the approaches of different nurses, making the HCA role difficult. Patients reported dissatisfaction with waits. Using a Lean quality improvement process with rapid PDSA cycles, the service changed to one in which patients were placed in a room, and remained there for the duration of their assessment. Standard work was developed for HCWs and nurses. Rooms were standardised using 5S processes, and set up improved to reduce time spent looking for supplies. A co-ordinator role was introduced using existing staff to monitor flow and to organise the required medical assessments and ECGs. Timing of booked appointments were altered to take account of clinic times. Routes in to the department were reduced from nine to one. Ten months after the work began, the average lead time had reduced to 59 minutes. The proportion of people attending within two weeks of their surgery decreased from 9.3% to 5.3%. Referrals for an anaesthetic opinion decreased from 30% to 20%, and in the month reviewed no one had to return to

  3. Recce mission planning

    NASA Astrophysics Data System (ADS)

    York, Andrew M.

    2000-11-01

    The ever increasing sophistication of reconnaissance sensors reinforces the importance of timely, accurate, and equally sophisticated mission planning capabilities. Precision targeting and zero-tolerance for collateral damage and civilian casualties, stress the need for accuracy and timeliness. Recent events have highlighted the need for improvement in current planning procedures and systems. Annotating printed maps takes time and does not allow flexibility for rapid changes required in today's conflicts. We must give aircrew the ability to accurately navigate their aircraft to an area of interest, correctly position the sensor to obtain the required sensor coverage, adapt missions as required, and ensure mission success. The growth in automated mission planning system capability and the expansion of those systems to include dedicated and integrated reconnaissance modules, helps to overcome current limitations. Mission planning systems, coupled with extensive integrated visualization capabilities, allow aircrew to not only plan accurately and quickly, but know precisely when they will locate the target and visualize what the sensor will see during its operation. This paper will provide a broad overview of the current capabilities and describe how automated mission planning and visualization systems can improve and enhance the reconnaissance planning process and contribute to mission success. Think about the ultimate objective of the reconnaissance mission as we consider areas that technology can offer improvement. As we briefly review the fundamentals, remember where and how TAC RECCE systems will be used. Try to put yourself in the mindset of those who are on the front lines, working long hours at increasingly demanding tasks, trying to become familiar with new operating areas and equipment, while striving to minimize risk and optimize mission success. Technical advancements that can reduce the TAC RECCE timeline, simplify operations and instill Warfighter

  4. Efficacy of a liquid low-energy formula diet in achieving preoperative target weight loss before bariatric surgery.

    PubMed

    Nielsen, Lone V; Nielsen, Mette S; Schmidt, Julie B; Pedersen, Sue D; Sjödin, Anders

    2016-01-01

    A preoperative weight loss of 8 % is a prerequisite to undergo bariatric surgery (BS) in Denmark. The aim of the present study was to evaluate the efficacy of a 7- or an 11-week low-energy diet (LCD) for achieving preoperative target weight before BS. A total of thirty obese patients (BMI 46·0 (sd 4·4) kg/m(2)) followed an LCD (Cambridge Weight Plan(®), 4184 kJ/d (1000 kcal/d)) for 7 or 11 weeks as preparation for BS. Anthropometric measurements including body composition (dual-energy X-ray absorptiometry), blood parameters and blood pressure were assessed at weeks 0, 7 and 11. At week 7, the majority of patients (77 %) had reached their target weight, and this was achieved after 5·4 (sem 0·3) weeks. Mean weight loss was 9·3 (sem 0·5) % (P < 0·01) and consisted of 41·6 % fat-free mass (FFM) and 58·4 % fat mass. The weight loss was accompanied by a decrease in systolic and diastolic blood pressure (7·1 (sem 2·3) and 7·3 (sem 1·8) mmHg, respectively, all P < 0·01) as well as an improved metabolic profile (8·2 (sem 1·8) % decrease in fasting glucose (P < 0·01), 28·6 (sem 6·4) % decrease in fasting insulin (P < 0·01), 23·1 (sem 2·2) % decrease in LDL (P < 0·01), and 9·7 (sem 4·7) % decrease in TAG (P < 0·05)). Weight, FFM and fat mass continued to decrease from week 7 to 11 (all P < 0·01), whereas no additional improvements was observed in the metabolic parameters. Severely obese patients can safely achieve preoperative target weight on an LCD within 7 weeks as part of preparation for BS. However, the considerable reduction in FFM in severely obese subjects needs further investigation. PMID:27293559

  5. High Frequency QRS ECG Accurately Detects Cardiomyopathy

    NASA Technical Reports Server (NTRS)

    Schlegel, Todd T.; Arenare, Brian; Poulin, Gregory; Moser, Daniel R.; Delgado, Reynolds

    2005-01-01

    High frequency (HF, 150-250 Hz) analysis over the entire QRS interval of the ECG is more sensitive than conventional ECG for detecting myocardial ischemia. However, the accuracy of HF QRS ECG for detecting cardiomyopathy is unknown. We obtained simultaneous resting conventional and HF QRS 12-lead ECGs in 66 patients with cardiomyopathy (EF = 23.2 plus or minus 6.l%, mean plus or minus SD) and in 66 age- and gender-matched healthy controls using PC-based ECG software recently developed at NASA. The single most accurate ECG parameter for detecting cardiomyopathy was an HF QRS morphological score that takes into consideration the total number and severity of reduced amplitude zones (RAZs) present plus the clustering of RAZs together in contiguous leads. This RAZ score had an area under the receiver operator curve (ROC) of 0.91, and was 88% sensitive, 82% specific and 85% accurate for identifying cardiomyopathy at optimum score cut-off of 140 points. Although conventional ECG parameters such as the QRS and QTc intervals were also significantly longer in patients than controls (P less than 0.001, BBBs excluded), these conventional parameters were less accurate (area under the ROC = 0.77 and 0.77, respectively) than HF QRS morphological parameters for identifying underlying cardiomyopathy. The total amplitude of the HF QRS complexes, as measured by summed root mean square voltages (RMSVs), also differed between patients and controls (33.8 plus or minus 11.5 vs. 41.5 plus or minus 13.6 mV, respectively, P less than 0.003), but this parameter was even less accurate in distinguishing the two groups (area under ROC = 0.67) than the HF QRS morphologic and conventional ECG parameters. Diagnostic accuracy was optimal (86%) when the RAZ score from the HF QRS ECG and the QTc interval from the conventional ECG were used simultaneously with cut-offs of greater than or equal to 40 points and greater than or equal to 445 ms, respectively. In conclusion 12-lead HF QRS ECG employing

  6. Phase II Study of Preoperative Concurrent Chemoradiation Therapy With S-1 in Patients With T4 Oral Squamous Cell Carcinoma

    SciTech Connect

    Nomura, Tomoko; Murakami, Ryuji; Toya, Ryo; Teshima, Keiko; Nakahara, Aya; Hirai, Toshinori; Hiraki, Akimitsu; Nakayama, Hideki; Yoshitake, Yoshihiro; Ota, Kazutoshi; Obayashi, Takehisa; Yamashita, Yasuyuki; Oya, Natsuo; Shinohara, Masanori

    2010-04-15

    Purpose: To determine the feasibility and efficacy of preoperative concurrent chemoradiation therapy (CCRT) with S-1, an oral fluoropyrimidine derivative, in patients with T4 oral squamous cell carcinoma (SCC). Methods and Materials: Only patients with histologically proven T4 oral SCC were included. Radiotherapy (total dose, 30 Gy) was delivered in 2-Gy daily fractions over a period of 3 weeks. Concurrently, S-1 (80 mg/m{sup 2}/day) was administered orally twice daily for 14 consecutive days. Results: We enrolled 46 patients. All underwent radiotherapy as planned; however, oral S-1 was discontinued in 3 patients who manifested acute toxicity. Grade 3 toxicities were mucositis (20%), anorexia (9%), and neutropenia (4%). We encountered no Grade 4 adverse events or serious postoperative morbidity requiring surgical intervention. After CCRT, 32 of the 46 patients underwent radical resection; in 17 (53%) of the operated patients, the pathologic response was complete. During follow-up ranging from 7 to 58 months (median, 22 months), tumor control failed in 5 (16%) of the 32 operated patients; there were 3 local and 2 regional failures. Of the 14 non-operated patients, 8 (57%) manifested local (n = 7) or regional failure (n = 1). The 3-year overall survival rate for all 46 patients was 69%; it was significantly higher for operated than for non-operated patients (82% vs. 48%; p = 0.0288). Conclusion: Preoperative CCRT with S-1 is feasible and effective in patients with T4 oral SCC. Even in inoperable cases, CCRT with S-1 provides adequate tumor control.

  7. Three-Dimensional Analysis of Recurrence Patterns in Rectal Cancer: The Cranial Border in Hypofractionated Preoperative Radiotherapy Can Be Lowered

    SciTech Connect

    Nijkamp, Jasper; Kusters, Miranda; Beets-Tan, Regina G.H.; Martijn, Hendrik; Beets, Geerard L.; Velde, Cornelis J.H. van de; Marijnen, Corrie A.M.

    2011-05-01

    Purpose: The aim of this study was to determine whether and where the radiotherapy (RT) clinical target volume (CTV) could be reduced in short-course preoperative treatment of rectal cancer patients. Methods and Materials: Patients treated in the Dutch total mesorectal excision trial, with a local recurrence were analyzed. For 94 (25 who underwent radiation therapy 69 who did not) of 114 patients with a local recurrence, the location of the recurrence was placed in a three-dimensionalthree (3D) model. The data in the 3D model were correlated to the clinical trial data to distinguish a group of patients eligible for CTV reduction. Effects of CTV reduction on dose to the small bowel was tested retrospectively in a dataset of 8 patients with three-field conformal plans and intensity-modulated RT (IMRT). Results: The use of preoperative RT mainly reduces anastomotic, lateral, and perineal recurrences. In patients without primary nodal involvement, no recurrences were found cranially of the S2-S3 interspace, irrespective of the delivery of RT. In patients without primary nodal involvement and a negative circumferential resection margin (CRM), only one recurrence was found cranial to the S2-S3 interspace. With a cranially reduced CTV to the S2-S3 interspace, over 60% reduction in absolute small bowel exposure at dose levels from 15 to 35 Gy could be achieved with three-field conventional RT, increasing to 80% when IMRT is also added. Conclusions: The cranial border of the CTV can safely be lowered for patients without expected nodal or CRM involvement, yielding a significant reduction of dose to the small bowel. Therefore, a significant reduction of acute and late toxicity can be expected.

  8. Preoperative education for lumbar radiculopathy: A survey of US spine surgeons

    PubMed Central

    Louw, Adriaan; Butler, David S.; Diener, Ina; Puentedura, Emilio J.

    2012-01-01

    Background We sought to determine current utilization, importance, content, and delivery methods of preoperative education by spine surgeons in the United States for patients with lumbar radiculopathy. Methods An online cross-sectional survey was used to study a random sample of spine surgeons in the United States. The Spinal Surgery Education Questionnaire (SSEQ) was developed based on previous related surveys and assessed for face and content validity by an expert panel. The SSEQ captured information on demographics, content, delivery methods, utilization, and importance of preoperative education as rated by surgeons. Descriptive statistics were used to describe the current utilization, importance, content, and delivery methods of preoperative education by spine surgeons in the United States for patients with lumbar radiculopathy. Results Of 200 surgeons, 89 (45% response rate) responded to the online survey. The majority (64.2%) provide preoperative education informally during the course of clinical consultation versus a formal preoperative education session. The mean time from the decision to undergo surgery to the date of surgery was 33.65 days. The highest rated educational topics are surgical procedure (96.3%), complications (96.3%), outcomes/expectations (93.8%), anatomy (92.6%), amount of postoperative pain expected (90.1%), and hospital stay (90.1%). Surgeons estimated spending approximately 20% of the preoperative education time specifically addressing pain. Seventy-five percent of the surgeons personally provide the education, and nearly all surgeons (96.3%) use verbal communication with the use of a spine model. Conclusions Spine surgeons believe that preoperative education is important and use a predominantly biomedical approach in preparing patients for surgery. Larger studies are needed to validate these findings. PMID:25694882

  9. Treatment Guidelines for Preoperative Radiation Therapy for Retroperitoneal Sarcoma: Preliminary Consensus of an International Expert Panel

    SciTech Connect

    Baldini, Elizabeth H.; Wang, Dian; Haas, Rick L.M.; Catton, Charles N.; Indelicato, Daniel J.; Kirsch, David G.; Roberge, David; Salerno, Kilian; Deville, Curtiland; Guadagnolo, B. Ashleigh; O'Sullivan, Brian; Petersen, Ivy A.; Le Pechoux, Cecile; Abrams, Ross A.; DeLaney, Thomas F.

    2015-07-01

    Purpose: Evidence for external beam radiation therapy (RT) as part of treatment for retroperitoneal sarcoma (RPS) is limited. Preoperative RT is the subject of a current randomized trial, but the results will not be available for many years. In the meantime, many practitioners use preoperative RT for RPS, and although this approach is used in practice, there are no radiation treatment guidelines. An international expert panel was convened to develop consensus treatment guidelines for preoperative RT for RPS. Methods and Materials: An expert panel of 15 academic radiation oncologists who specialize in the treatment of sarcoma was assembled. A systematic review of reports related to RT for RPS, RT for extremity sarcoma, and RT-related toxicities for organs at risk was performed. Due to the paucity of high-quality published data on the subject of RT for RPS, consensus recommendations were based largely on expert opinion derived from clinical experience and extrapolation of relevant published reports. It is intended that these clinical practice guidelines be updated as pertinent data become available. Results: Treatment guidelines for preoperative RT for RPS are presented. Conclusions: An international panel of radiation oncologists who specialize in sarcoma reached consensus guidelines for preoperative RT for RPS. Many of the recommendations are based on expert opinion because of the absence of higher level evidence and, thus, are best regarded as preliminary. We emphasize that the role of preoperative RT for RPS has not been proven, and we await data from the European Organization for Research and Treatment of Cancer (EORTC) study of preoperative radiotherapy plus surgery versus surgery alone for patients with RPS. Further data are also anticipated pertaining to normal tissue dose constraints, particularly for bowel tolerance. Nonetheless, as we await these data, the guidelines herein can be used to establish treatment uniformity to aid future assessments of efficacy

  10. Accurately Mapping M31's Microlensing Population

    NASA Astrophysics Data System (ADS)

    Crotts, Arlin

    2004-07-01

    We propose to augment an existing microlensing survey of M31 with source identifications provided by a modest amount of ACS {and WFPC2 parallel} observations to yield an accurate measurement of the masses responsible for microlensing in M31, and presumably much of its dark matter. The main benefit of these data is the determination of the physical {or "einstein"} timescale of each microlensing event, rather than an effective {"FWHM"} timescale, allowing masses to be determined more than twice as accurately as without HST data. The einstein timescale is the ratio of the lensing cross-sectional radius and relative velocities. Velocities are known from kinematics, and the cross-section is directly proportional to the {unknown} lensing mass. We cannot easily measure these quantities without knowing the amplification, hence the baseline magnitude, which requires the resolution of HST to find the source star. This makes a crucial difference because M31 lens m ass determinations can be more accurate than those towards the Magellanic Clouds through our Galaxy's halo {for the same number of microlensing events} due to the better constrained geometry in the M31 microlensing situation. Furthermore, our larger survey, just completed, should yield at least 100 M31 microlensing events, more than any Magellanic survey. A small amount of ACS+WFPC2 imaging will deliver the potential of this large database {about 350 nights}. For the whole survey {and a delta-function mass distribution} the mass error should approach only about 15%, or about 6% error in slope for a power-law distribution. These results will better allow us to pinpoint the lens halo fraction, and the shape of the halo lens spatial distribution, and allow generalization/comparison of the nature of halo dark matter in spiral galaxies. In addition, we will be able to establish the baseline magnitude for about 50, 000 variable stars, as well as measure an unprecedentedly deta iled color-magnitude diagram and luminosity

  11. Accurate measurement of unsteady state fluid temperature

    NASA Astrophysics Data System (ADS)

    Jaremkiewicz, Magdalena

    2016-07-01

    In this paper, two accurate methods for determining the transient fluid temperature were presented. Measurements were conducted for boiling water since its temperature is known. At the beginning the thermometers are at the ambient temperature and next they are immediately immersed into saturated water. The measurements were carried out with two thermometers of different construction but with the same housing outer diameter equal to 15 mm. One of them is a K-type industrial thermometer widely available commercially. The temperature indicated by the thermometer was corrected considering the thermometers as the first or second order inertia devices. The new design of a thermometer was proposed and also used to measure the temperature of boiling water. Its characteristic feature is a cylinder-shaped housing with the sheath thermocouple located in its center. The temperature of the fluid was determined based on measurements taken in the axis of the solid cylindrical element (housing) using the inverse space marching method. Measurements of the transient temperature of the air flowing through the wind tunnel using the same thermometers were also carried out. The proposed measurement technique provides more accurate results compared with measurements using industrial thermometers in conjunction with simple temperature correction using the inertial thermometer model of the first or second order. By comparing the results, it was demonstrated that the new thermometer allows obtaining the fluid temperature much faster and with higher accuracy in comparison to the industrial thermometer. Accurate measurements of the fast changing fluid temperature are possible due to the low inertia thermometer and fast space marching method applied for solving the inverse heat conduction problem.

  12. Accurate upwind methods for the Euler equations

    NASA Technical Reports Server (NTRS)

    Huynh, Hung T.

    1993-01-01

    A new class of piecewise linear methods for the numerical solution of the one-dimensional Euler equations of gas dynamics is presented. These methods are uniformly second-order accurate, and can be considered as extensions of Godunov's scheme. With an appropriate definition of monotonicity preservation for the case of linear convection, it can be shown that they preserve monotonicity. Similar to Van Leer's MUSCL scheme, they consist of two key steps: a reconstruction step followed by an upwind step. For the reconstruction step, a monotonicity constraint that preserves uniform second-order accuracy is introduced. Computational efficiency is enhanced by devising a criterion that detects the 'smooth' part of the data where the constraint is redundant. The concept and coding of the constraint are simplified by the use of the median function. A slope steepening technique, which has no effect at smooth regions and can resolve a contact discontinuity in four cells, is described. As for the upwind step, existing and new methods are applied in a manner slightly different from those in the literature. These methods are derived by approximating the Euler equations via linearization and diagonalization. At a 'smooth' interface, Harten, Lax, and Van Leer's one intermediate state model is employed. A modification for this model that can resolve contact discontinuities is presented. Near a discontinuity, either this modified model or a more accurate one, namely, Roe's flux-difference splitting. is used. The current presentation of Roe's method, via the conceptually simple flux-vector splitting, not only establishes a connection between the two splittings, but also leads to an admissibility correction with no conditional statement, and an efficient approximation to Osher's approximate Riemann solver. These reconstruction and upwind steps result in schemes that are uniformly second-order accurate and economical at smooth regions, and yield high resolution at discontinuities.

  13. Preoperative Medical Evaluation: Part 1: General Principles and Cardiovascular Considerations

    PubMed Central

    Becker, Daniel E

    2009-01-01

    A thorough assessment of a patient's medical status is standard practice when dental care is provided. Although this is true for procedures performed under local anesthesia alone, the information gathered may be viewed somewhat differently if the dentist is planning to use sedation or general anesthesia as an adjunct to dental treatment. This article is the first of a 2-part sequence and will address general principles and cardiovascular considerations. A second article will address pulmonary, metabolic, and miscellaneous disorders. PMID:19769423

  14. The first accurate description of an aurora

    NASA Astrophysics Data System (ADS)

    Schröder, Wilfried

    2006-12-01

    As technology has advanced, the scientific study of auroral phenomena has increased by leaps and bounds. A look back at the earliest descriptions of aurorae offers an interesting look into how medieval scholars viewed the subjects that we study.Although there are earlier fragmentary references in the literature, the first accurate description of the aurora borealis appears to be that published by the German Catholic scholar Konrad von Megenberg (1309-1374) in his book Das Buch der Natur (The Book of Nature). The book was written between 1349 and 1350.

  15. Are Kohn-Sham conductances accurate?

    PubMed

    Mera, H; Niquet, Y M

    2010-11-19

    We use Fermi-liquid relations to address the accuracy of conductances calculated from the single-particle states of exact Kohn-Sham (KS) density functional theory. We demonstrate a systematic failure of this procedure for the calculation of the conductance, and show how it originates from the lack of renormalization in the KS spectral function. In certain limits this failure can lead to a large overestimation of the true conductance. We also show, however, that the KS conductances can be accurate for single-channel molecular junctions and systems where direct Coulomb interactions are strongly dominant. PMID:21231333

  16. Accurate density functional thermochemistry for larger molecules.

    SciTech Connect

    Raghavachari, K.; Stefanov, B. B.; Curtiss, L. A.; Lucent Tech.

    1997-06-20

    Density functional methods are combined with isodesmic bond separation reaction energies to yield accurate thermochemistry for larger molecules. Seven different density functionals are assessed for the evaluation of heats of formation, Delta H 0 (298 K), for a test set of 40 molecules composed of H, C, O and N. The use of bond separation energies results in a dramatic improvement in the accuracy of all the density functionals. The B3-LYP functional has the smallest mean absolute deviation from experiment (1.5 kcal mol/f).

  17. Preoperative systemic therapy in locoregional management of early breast cancer: highlights from the Kyoto Breast Cancer Consensus Conference.

    PubMed

    Toi, Masakazu; Benson, John R; Winer, Eric P; Forbes, John F; von Minckwitz, Gunter; Golshan, Mehra; Robertson, John F R; Sasano, Hironobu; Cole, Bernard F; Chow, Louis W C; Pegram, Mark D; Han, Wonshik; Huang, Chiun-Sheng; Ikeda, Tadashi; Kanao, Shotaro; Lee, Eun-Sook; Noguchi, Shinzaburo; Ohno, Shinji; Partridge, Ann H; Rouzier, Roman; Tozaki, Mitsuhiro; Sugie, Tomoharu; Yamauchi, Akira; Inamoto, Takashi

    2012-12-01

    Data reviewed at the Kyoto Breast Cancer Consensus Conference (KBCCC) showed that preoperative systemic therapy (PST) could optimize surgery through the utilization of information relating to pre- and post-PST tumor stage, therapeutic sensitivity, and treatment-induced changes in the biological characteristics of the tumor. As such, it was noted that the biological characteristics of the tumor, such as hormone receptors, human epidermal growth factor receptor-2, histological grade, cell proliferative activity, mainly defined by the Ki67 labeling index, and the tumor's multi-gene signature, should be considered in the planning of both systemic and local therapy. Furthermore, the timing of axillary sentinel lymph node diagnosis (i.e., before or after the PST) was also noted to be critical in that it may influence the likelihood of axillary preservation, even in node positive cases. In addition, axillary diagnosis with ultrasound and concomitant fine needle aspiration cytology or core needle biopsy (CNB) was reported to contribute to the construction of a treatment algorithm for patient-specific or individualized axillary surgery. Following PST, planning for breast surgery should therefore be based on tumor subtype, tumor volume and extent, therapeutic response to PST, and patient preference. Nomograms for predicting nodal status and drug sensitivity were also recognized as a tool to support decision-making in the selection of surgical treatment. Overall, review of data at the KBCCC showed that PST increases the likelihood of patients receiving localized surgery and individualized treatment regimens. PMID:23143284

  18. Use of three-dimensional medical modeling methods for precise planning of orthognathic surgery.

    PubMed

    Mavili, Mehmet Emin; Canter, Halil Ibrahim; Saglam-Aydinatay, Banu; Kamaci, Soner; Kocadereli, Ilken

    2007-07-01

    Stereolithographic (medical rapid prototyping) biomodeling allows three-dimensional computed tomography to be used to generate solid plastic replicas of anatomic structures. Reports in the literature suggest that such biomodels may have a use in maxillofacial surgery, craniofacial surgery, orthopedics, neurosurgery, otology, vascular, and nasal research. A prospective trial to assess the usefulness of biomodeling in orthognathic surgery has been performed. In 12 patients with mandibular prognathism and/or maxillary retrusion, in addition to routine preoperative cephalometric analysis, preoperative high-resolution (cutting slice thickness of 1 mm) three-dimensional computed tomography scan of the patients was obtained. Raw data obtained from computed tomography scanning was processed with a Mimics 9.22 Software (Materialise's Interactive Medical Image Control System, Belgium). Fabrication of three-dimensional medical models was obtained through a process called powder depositional modeling by use of a Spectrum Z 510 3D Color Printer (Z Corporation, Burlington, MA). Alveolar arches of the maxilla and mandibula of the models were replaced with orthodontic dental cast models. Temporomandibular joints of the models were fixed with Kirschner wire. Maxillary and mandibular bony segments were mobilized according to preoperative orthodontic planning done by analysis of cephalometric plain radiographs. The relation between proximal and distal mandibular segments after bilateral sagittal split osteotomies were evaluated on models preoperatively. The same surgeon had a role in both model cutting preoperatively and as an instructor preoperatively. The same bony relation was observed both in preoperative modelsand in the perioperative surgical field in all patients. Condylar malpositioning was not observed in any of the patients. Studying preoperative planned movements of osteotomized bone segments and observing relations of osteotomized segments of mandibula and maxilla in

  19. The effect of preoperative keratometry on visual outcomes after moderate myopic LASIK

    PubMed Central

    Christiansen, Steven M; Neuffer, Marcus C; Sikder, Shameema; Semnani, Rodmehr T; Moshirfar, Majid

    2012-01-01

    Purpose To evaluate visual outcomes in moderately myopic eyes with flat and steep corneas (preoperatively) that have been treated with laser-assisted in situ keratomileusis (LASIK). Patients and methods Records of ninety-six eyes with average preoperative keratometry (K) values between 39.9 and 42.0 diopters (D) (flat) were matched with 103 eyes with preoperative K values between 46.0 and 47.2 D (steep) that underwent LASIK between March 2007 and March 2010 for moderate myopia, and were retrospectively reviewed. The primary outcome measures used to determine the effect of preoperative keratometry on visual prognosis were refraction, visual acuity, change in keratometry (ΔK), and change in spherical equivalent (ΔSE), measured at 1, 3, 6, and 12 months postoperatively. Results Significant differences were found at 6 months postoperatively between the flat group and steep group in SE (P = 0.029), sphere (P = 0.018), ΔK (P = 0.002), percentage of eyes achieving SE of −0.25 to + 0.25 D (P = 0.0125), −0.26 to −0.50 D (P = 0.003), −0.51 to −1.00 D (P = 0.044), and the percentage of eyes achieving uncorrected distance visual acuity of 20/15 or better (P = 0.0006). Conclusion Moderately myopic eyes with flatter corneas preoperatively have better visual prognosis following LASIK compared with moderately myopic eyes with steeper corneas. PMID:22536037

  20. Effects of preoperative physiotherapy in hip osteoarthritis patients awaiting total hip replacement

    PubMed Central

    Czyżewska, Anna; Walesiak, Katarzyna; Krawczak, Karolina; Cabaj, Dominika; Górecki, Andrzej

    2014-01-01

    Introduction The World Health Organization (WHO) claimed osteoarthritis as a civilization-related disease. The effectiveness of preoperative physiotherapy among patients suffering hip osteoarthritis (OA) at the end of their conservative treatment is rarely described in the literature. The aim of this study was to assess the quality of life and musculoskeletal health status of patients who received preoperative physiotherapy before total hip replacement (THR) surgery within a year prior to admission for a scheduled THR and those who did not. Material and methods Forty-five patients, admitted to the Department of Orthopaedics and Traumatology of Locomotor System for elective total hip replacement surgery, were recruited for this study. The assessment consisted of a detailed interview using various questionnaires: the Harris Hip Score (HHS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the 36-Item Short Form Health Survey (SF-36), and the Hip disability and Osteoarthritis Outcome Score (HOOS), as well as physical examination. Patients were assigned to groups based on their attendance of preoperative physiotherapy within a year prior to surgery. Results Among patients who received preoperative physiotherapy a significant improvement was found for pain, daily functioning, vitality, psychological health, social life, and (active and passive) internal rotation (p < 0.05). Conclusions Patients are not routinely referred to physiotherapy within a year before total hip replacement surgery. This study confirmed that pre-operative physiotherapy may have a positive influence on selected musculoskeletal system status indicators and quality of life in hip osteoarthritis patients awaiting surgery. PMID:25395951

  1. Dipyridamole-thallium scanning in patients undergoing vascular surgery. Optimizing preoperative evaluation of cardiac risk

    SciTech Connect

    Eagle, K.A.; Singer, D.E.; Brewster, D.C.; Darling, R.C.; Mulley, A.G.; Boucher, C.A.

    1987-04-24

    Dipyridamole-thallium imaging has been suggested as a method of preoperatively assessing cardiac risk in patients undergoing major surgery. To define more clearly its proper role in preoperative assessment, we prospectively evaluated 111 patients undergoing vascular surgery. In the first set of 61 patients, our data confirmed the value of preoperative dipyridamole-thallium scanning in identifying the patients who suffered postoperative ischemic events. Events occurred in eight of 18 patients with reversible defects on preoperative imaging, compared with no events in 43 patients with no thallium redistribution (confidence interval for the risk difference: 0.624, 0.256). The results also suggested that clinical factors might allow identification of a low-risk subset of patients. To test the hypothesis that patients with no evidence of congestive heart failure, angina, prior myocardial infarction, or diabetes do not require further preoperative testing, we evaluated an additional 50 patients having vascular procedures. None of the 23 without the clinical markers had untoward outcomes, while ten of 27 patients with one or more of these clinical markers suffered postoperative ischemic events (confidence interval for the risk difference: 0.592, 0.148). In the clinical high-risk subset, further risk stratification is achieved with dipyridamole-thallium scanning.

  2. An evaluation of preoperative computed tomography on patients with chronic otitis media.

    PubMed

    Yildirim-Baylan, Muzeyyen; Ozmen, Cihan Akgul; Gun, Ramazan; Yorgancilar, Ediz; Akkuş, Zeki; Topcu, Ismail

    2012-03-01

    This study aimed to compare the veracity of computed tomography findings on patients undergoing surgery for chronic otitis media (COM) with the surgical findings, and to determine to what extent the preoperative computerized tomography (CT) findings are useful to the surgeon. A series of 56 patients with COM undergoing preoperative CT scanning followed by surgical exploration of the middle ear and mastoid. Operative notes were recorded and data collected on the nature of soft tissue masses, the status of the ossicles, presence or absence of facial canal dehiscence and semicircular canal (SCC) dehiscence and the presence or absence of dural plate erosion, and sigmoid sinus thrombosis. Fifty-six patients were recruited in the study, 30 males and 26 females. The age range was from 16 to 67 years with a mean of 26.51 ± 1.4 years. The preoperative CT scan imaging in cases of cholesteatoma, ossicular chain erosion and SCC dehiscence have good correlation with the intraoperative findings. The specificity of preoperative CT scan in detecting facial canal dehiscence, dural plate erosion and sigmoid sinus thrombosis in patient of COM were weak. Preoperative computed tomography evaluation is fairly useful especially in cases of cholesteatoma. According to the results of this study, CT is of value particularly in the definition of cholesteatoma, and in determining ossicular chain erosion and semicircular canal fistula. PMID:23449285

  3. The Impact of Race/Ethnicity on Preoperative Time to Hip Stabilization Procedure after Hip Fracture

    PubMed Central

    Nguyen-Oghalai, Tracy U.; Kuo, Yong-fang; Wu, Helen; Shokar, Navkiran K.; Grecula, Michael; Tincher, Steven; Ottenbacher, Kenneth J.

    2010-01-01

    Background We sought to examine the preoperative time for hip stabilization procedure among Hispanics, non-Hispanic blacks (blacks) and non-Hispanic whites (whites). Methods This was a secondary data analysis using Medicare claims data. Our analysis included 40,321 patients admitted for hip fracture hospitalization from 2001-2005. Our primary analysis was generalized linear modeling, and our dependent variable was preoperative time. Our independent variable was race/ethnicity (Hispanics, blacks versus whites), and covariates were age, gender, income, type of hip fracture and comorbidities. Results Bivariate analyses showed that both Hispanics and blacks experienced a longer preoperative time (P<0.01). The average (mean) of days to surgery was 1.2 for whites, 1.6 for blacks and 1.7 for Hispanics. The delayed preoperative time among Hispanics and blacks persisted after adjusting for covariates. Conclusions The delayed preoperative time among minorities suggests the need to closely monitor care among minorities with hip fracture to determine how to best address their developing needs. PMID:20375948

  4. 'Fit to fly': overcoming barriers to preoperative haemoglobin optimization in surgical patients.

    PubMed

    Muñoz, M; Gómez-Ramírez, S; Kozek-Langeneker, S; Shander, A; Richards, T; Pavía, J; Kehlet, H; Acheson, A G; Evans, C; Raobaikady, R; Javidroozi, M; Auerbach, M

    2015-07-01

    In major surgery, the implementation of multidisciplinary, multimodal and individualized strategies, collectively termed Patient Blood Management, aims to identify modifiable risks and optimise patients' own physiology with the ultimate goal of improving outcomes. Among the various strategies utilized in Patient Blood Management, timely detection and management of preoperative anaemia is most important, as it is in itself a risk factor for worse clinical outcome, but also one of the strongest predisposing factors for perioperative allogeneic blood transfusion, which in turn increases postoperative morbidity, mortality and costs. However, preoperative anaemia is still frequently ignored, with indiscriminate allogeneic blood transfusion used as a 'quick fix'. Consistent with reported evidence from other medical specialties, this imprudent practice continues to be endorsed by non-evidence based misconceptions, which constitute serious barriers for a wider implementation of preoperative haemoglobin optimisation. We have reviewed a number of these misconceptions, which we unanimously consider should be promptly abandoned by health care providers and replaced by evidence-based strategies such as detection, diagnosis and proper treatment of preoperative anaemia. We believe that this approach to preoperative anaemia management may be a viable, cost-effective strategy that is beneficial both for patients, with improved clinical outcomes, and for health systems, with more efficient use of finite health care resources. PMID:26089443

  5. Total Versus Hemiarthroplasty for Glenohumeral Arthritis According to Preoperative Glenoid Erosion

    PubMed Central

    Pastor, Marc-Frederic; Kaufmann, Melena; Gettmann, Andre; Wellmann, Mathias; Smith, Tomas

    2015-01-01

    Clinical studies on primary osteoarthritis have shown better results of total shoulder arthroplasty (TSA) compared to hemiarthroplasty (HA) regarding the function, revision rate and postoperative pain relief. However, a clear recommendation for implantation of TSA or HA, depending on the glenoid type of erosion, does not exist. The aim of the study was to compare the results of TSA and HA with respect to the preoperative glenoid type. In this study, 41 patients were examined retrospectively; among them, 25 patients were treated with stemmed anatomic TSA and 16 with stemmed anatomic HA. The degree of osteoarthritis was determined according to Samilson and the glenoid erosion was classified according to Walch. The clinical outcome of the patients was determined by using the Constant Score (CS) and the Simple Shoulder Test at final follow-up. Patients after TSA demonstrated a significantly improved internal rotation compared to HA patients. Patients with preoperative B1 glenoid showed better pain relief after TSA compared to HA. For patients with preoperative type A2 glenoid a significantly higher CS was found after TSA compared to HA. We were able to show good short-term results after TSA and HA. Our findings suggest a better internal rotation for TSA compared to HA, superior clinical outcome for patients with preoperative A2 glenoid and lower pain level for patients with a preoperative B1 glenoid. However, these results need to be confirmed by further studies. PMID:26330995

  6. Accurate basis set truncation for wavefunction embedding

    NASA Astrophysics Data System (ADS)

    Barnes, Taylor A.; Goodpaster, Jason D.; Manby, Frederick R.; Miller, Thomas F.

    2013-07-01

    Density functional theory (DFT) provides a formally exact framework for performing embedded subsystem electronic structure calculations, including DFT-in-DFT and wavefunction theory-in-DFT descriptions. In the interest of efficiency, it is desirable to truncate the atomic orbital basis set in which the subsystem calculation is performed, thus avoiding high-order scaling with respect to the size of the MO virtual space. In this study, we extend a recently introduced projection-based embedding method [F. R. Manby, M. Stella, J. D. Goodpaster, and T. F. Miller III, J. Chem. Theory Comput. 8, 2564 (2012)], 10.1021/ct300544e to allow for the systematic and accurate truncation of the embedded subsystem basis set. The approach is applied to both covalently and non-covalently bound test cases, including water clusters and polypeptide chains, and it is demonstrated that errors associated with basis set truncation are controllable to well within chemical accuracy. Furthermore, we show that this approach allows for switching between accurate projection-based embedding and DFT embedding with approximate kinetic energy (KE) functionals; in this sense, the approach provides a means of systematically improving upon the use of approximate KE functionals in DFT embedding.

  7. Accurate radiative transfer calculations for layered media.

    PubMed

    Selden, Adrian C

    2016-07-01

    Simple yet accurate results for radiative transfer in layered media with discontinuous refractive index are obtained by the method of K-integrals. These are certain weighted integrals applied to the angular intensity distribution at the refracting boundaries. The radiative intensity is expressed as the sum of the asymptotic angular intensity distribution valid in the depth of the scattering medium and a transient term valid near the boundary. Integrated boundary equations are obtained, yielding simple linear equations for the intensity coefficients, enabling the angular emission intensity and the diffuse reflectance (albedo) and transmittance of the scattering layer to be calculated without solving the radiative transfer equation directly. Examples are given of half-space, slab, interface, and double-layer calculations, and extensions to multilayer systems are indicated. The K-integral method is orders of magnitude more accurate than diffusion theory and can be applied to layered scattering media with a wide range of scattering albedos, with potential applications to biomedical and ocean optics. PMID:27409700

  8. Fast and accurate propagation of coherent light

    PubMed Central

    Lewis, R. D.; Beylkin, G.; Monzón, L.

    2013-01-01

    We describe a fast algorithm to propagate, for any user-specified accuracy, a time-harmonic electromagnetic field between two parallel planes separated by a linear, isotropic and homogeneous medium. The analytical formulation of this problem (ca 1897) requires the evaluation of the so-called Rayleigh–Sommerfeld integral. If the distance between the planes is small, this integral can be accurately evaluated in the Fourier domain; if the distance is very large, it can be accurately approximated by asymptotic methods. In the large intermediate region of practical interest, where the oscillatory Rayleigh–Sommerfeld kernel must be applied directly, current numerical methods can be highly inaccurate without indicating this fact to the user. In our approach, for any user-specified accuracy ϵ>0, we approximate the kernel by a short sum of Gaussians with complex-valued exponents, and then efficiently apply the result to the input data using the unequally spaced fast Fourier transform. The resulting algorithm has computational complexity , where we evaluate the solution on an N×N grid of output points given an M×M grid of input samples. Our algorithm maintains its accuracy throughout the computational domain. PMID:24204184

  9. How Accurately can we Calculate Thermal Systems?

    SciTech Connect

    Cullen, D; Blomquist, R N; Dean, C; Heinrichs, D; Kalugin, M A; Lee, M; Lee, Y; MacFarlan, R; Nagaya, Y; Trkov, A

    2004-04-20

    I would like to determine how accurately a variety of neutron transport code packages (code and cross section libraries) can calculate simple integral parameters, such as K{sub eff}, for systems that are sensitive to thermal neutron scattering. Since we will only consider theoretical systems, we cannot really determine absolute accuracy compared to any real system. Therefore rather than accuracy, it would be more precise to say that I would like to determine the spread in answers that we obtain from a variety of code packages. This spread should serve as an excellent indicator of how accurately we can really model and calculate such systems today. Hopefully, eventually this will lead to improvements in both our codes and the thermal scattering models that they use in the future. In order to accomplish this I propose a number of extremely simple systems that involve thermal neutron scattering that can be easily modeled and calculated by a variety of neutron transport codes. These are theoretical systems designed to emphasize the effects of thermal scattering, since that is what we are interested in studying. I have attempted to keep these systems very simple, and yet at the same time they include most, if not all, of the important thermal scattering effects encountered in a large, water-moderated, uranium fueled thermal system, i.e., our typical thermal reactors.

  10. Accurate shear measurement with faint sources

    SciTech Connect

    Zhang, Jun; Foucaud, Sebastien; Luo, Wentao E-mail: walt@shao.ac.cn

    2015-01-01

    For cosmic shear to become an accurate cosmological probe, systematic errors in the shear measurement method must be unambiguously identified and corrected for. Previous work of this series has demonstrated that cosmic shears can be measured accurately in Fourier space in the presence of background noise and finite pixel size, without assumptions on the morphologies of galaxy and PSF. The remaining major source of error is source Poisson noise, due to the finiteness of source photon number. This problem is particularly important for faint galaxies in space-based weak lensing measurements, and for ground-based images of short exposure times. In this work, we propose a simple and rigorous way of removing the shear bias from the source Poisson noise. Our noise treatment can be generalized for images made of multiple exposures through MultiDrizzle. This is demonstrated with the SDSS and COSMOS/ACS data. With a large ensemble of mock galaxy images of unrestricted morphologies, we show that our shear measurement method can achieve sub-percent level accuracy even for images of signal-to-noise ratio less than 5 in general, making it the most promising technique for cosmic shear measurement in the ongoing and upcoming large scale galaxy surveys.

  11. Accurate pose estimation for forensic identification

    NASA Astrophysics Data System (ADS)

    Merckx, Gert; Hermans, Jeroen; Vandermeulen, Dirk

    2010-04-01

    In forensic authentication, one aims to identify the perpetrator among a series of suspects or distractors. A fundamental problem in any recognition system that aims for identification of subjects in a natural scene is the lack of constrains on viewing and imaging conditions. In forensic applications, identification proves even more challenging, since most surveillance footage is of abysmal quality. In this context, robust methods for pose estimation are paramount. In this paper we will therefore present a new pose estimation strategy for very low quality footage. Our approach uses 3D-2D registration of a textured 3D face model with the surveillance image to obtain accurate far field pose alignment. Starting from an inaccurate initial estimate, the technique uses novel similarity measures based on the monogenic signal to guide a pose optimization process. We will illustrate the descriptive strength of the introduced similarity measures by using them directly as a recognition metric. Through validation, using both real and synthetic surveillance footage, our pose estimation method is shown to be accurate, and robust to lighting changes and image degradation.

  12. Accurate determination of characteristic relative permeability curves

    NASA Astrophysics Data System (ADS)

    Krause, Michael H.; Benson, Sally M.

    2015-09-01

    A recently developed technique to accurately characterize sub-core scale heterogeneity is applied to investigate the factors responsible for flowrate-dependent effective relative permeability curves measured on core samples in the laboratory. The dependency of laboratory measured relative permeability on flowrate has long been both supported and challenged by a number of investigators. Studies have shown that this apparent flowrate dependency is a result of both sub-core scale heterogeneity and outlet boundary effects. However this has only been demonstrated numerically for highly simplified models of porous media. In this paper, flowrate dependency of effective relative permeability is demonstrated using two rock cores, a Berea Sandstone and a heterogeneous sandstone from the Otway Basin Pilot Project in Australia. Numerical simulations of steady-state coreflooding experiments are conducted at a number of injection rates using a single set of input characteristic relative permeability curves. Effective relative permeability is then calculated from the simulation data using standard interpretation methods for calculating relative permeability from steady-state tests. Results show that simplified approaches may be used to determine flowrate-independent characteristic relative permeability provided flow rate is sufficiently high, and the core heterogeneity is relatively low. It is also shown that characteristic relative permeability can be determined at any typical flowrate, and even for geologically complex models, when using accurate three-dimensional models.

  13. Intraocular lens power estimation by accurate ray tracing for eyes underwent previous refractive surgeries

    NASA Astrophysics Data System (ADS)

    Yang, Que; Wang, Shanshan; Wang, Kai; Zhang, Chunyu; Zhang, Lu; Meng, Qingyu; Zhu, Qiudong

    2015-08-01

    For normal eyes without history of any ocular surgery, traditional equations for calculating intraocular lens (IOL) power, such as SRK-T, Holladay, Higis, SRK-II, et al., all were relativley accurate. However, for eyes underwent refractive surgeries, such as LASIK, or eyes diagnosed as keratoconus, these equations may cause significant postoperative refractive error, which may cause poor satisfaction after cataract surgery. Although some methods have been carried out to solve this problem, such as Hagis-L equation[1], or using preoperative data (data before LASIK) to estimate K value[2], no precise equations were available for these eyes. Here, we introduced a novel intraocular lens power estimation method by accurate ray tracing with optical design software ZEMAX. Instead of using traditional regression formula, we adopted the exact measured corneal elevation distribution, central corneal thickness, anterior chamber depth, axial length, and estimated effective lens plane as the input parameters. The calculation of intraocular lens power for a patient with keratoconus and another LASIK postoperative patient met very well with their visual capacity after cataract surgery.

  14. Evaluation of preoperative staging for esophageal squamous cell carcinoma

    PubMed Central

    Luo, Lin-Na; He, Long-Jun; Gao, Xiao-Yan; Huang, Xin-Xin; Shan, Hong-Bo; Luo, Guang-Yu; Li, Yin; Lin, Shi-Yong; Wang, Guo-Bao; Zhang, Rong; Xu, Guo-Liang; Li, Jian-Jun

    2016-01-01

    Esophageal squamous cell carcinoma (ESCC) is known for its rapid progression and poor outcomes. China has the highest incidence and mortality in the world. Diagnoses made at early stages and accurate staging are associated with better outcomes, all of which can play a significant role in the selection of treatment protocols. ESCC is staged according to the widely accepted TNM system. Common imaging modalities used in staging ESCC before treatment include endoscopy, computed tomography (CT), positron emission tomography (PET) and magnetic resonance imaging (MRI). Endoscopic ultrasound is useful for staging tumor depth and nodal status. Narrow band imaging is valuable for early stage disease assessment. CT and PET provide additional valuable information regarding node and metastasis staging. The ability of MRI to delineate ESCC is continuously being improved and adds information regarding locoregional status to routine examinations. PMID:27547011

  15. Preoperative Nutritional Assessment in Elderly Cancer Patients Undergoing Elective Surgery: MNA or PG-SGA?

    PubMed

    Dubhashi, S P; Kayal, Akshat

    2015-12-01

    This study aims to evaluate and compare the use of patient-generated subjective global assessment (PG-SGA) and mini nutritional assessment (MNA) as a preoperative nutritional assessment tool in elderly cancer patients. This was a prospective study carried out on 47 patients, 45 years and above suffering from cancer and admitted to Padmashree Dr. D.Y. Patil Medical College and Hospital, Pune. The patients were evaluated with PG-SGA and MNA tools at the time of admission and baseline data were collected. All patients had undergone surgeries as per indications. Postoperatively, the surgical outcomes and adverse events were noted and statistically evaluated. The average age of the study sample was 61.46 years and 29 patients were females. The patients classified by PG-SGA were ten in group A and 37 in group B and C. The patients classified by MNA were five in no risk group and 42 in group with patients at risk and malnourished. When evaluated with PG-SGA in group B and C, wound infections and requirement of change of antibiotic were seen in 86.4 % patients and their average day of onset of infection was 5.6 days. Antibiotics were administered to these patients for an average of 14.2 days and their average duration of stay was 29 days. On the other hand, the evaluation of patients with MNA, at risk and malnourished patients, wound infections, and requirement of change of antibiotic were seen in 81 % of patients and their average day of onset of infection was 5.6 days. Antibiotics were administered to these patients for an average of 13.8 days and their average duration of stay was 27 days. The results were statistically significant. The mini nutritional assessment is more exhaustive in identifying patients at risk and is useful in screening populations to identify frail elderly persons allowing us to intervene earlier, thereby improving the patient prognosis. The patient-generated subjective global assessment is a more comprehensive tool for elderly cancer

  16. A Model for Better Leveraging the Point of Preoperative Assessment: Patients and Providers Look Beyond Operative Indications When Making Decisions.

    PubMed

    Nelson, Olivia; Quinn, Timothy D; Arriaga, Alexander F; Hepner, David L; Lipsitz, Stuart R; Cooper, Zara; Gawande, Atul A; Bader, Angela M

    2016-04-15

    Previous literature on preoperative evaluation focuses on the impact on the day of surgery cancellations and delays; however, the framework of cancellations and delays at the time of the elective outpatient preoperative anesthesia visit has not been categorized. We describe the current model in the preoperative clinic at Brigham and Women's Hospital, examining the pattern of cancellations at the time of this preoperative visit and the framework used for categorizing the issues involved. Looking at this broader framework is important in an era of patient-centered care; we seek to identify targets to modify the preoperative assessment and adequately assess and capture the spectrum of issues involved. Elective cases evaluated in the preoperative clinic were reviewed over 10 months. Characteristics of cancelled and noncancelled cases were compared. In-depth analysis of issues related to cancellation was done; 1-year follow-up was completed. Cancellation patterns included categories encompassing clinical, financial, alignment with patient values and goals, compliance, and social issues. The period of preoperative assessment can therefore be leveraged to review a number of domains that can adversely affect surgical outcomes and improve patient-centered care. Also, our framework allows the institution to benchmark these patterns over time; increases in cancellations at the time of the preoperative anesthesia clinic visit for specific categories can prompt an opportunity to examine and improve preoperative workflow. PMID:26669650

  17. A review of the evidence for active preoperative warming of adults undergoing general anesthesia.

    PubMed

    Roberson, Michael C; Dieckmann, Loraine S; Rodriguez, Ricardo E; Austin, Paul N

    2013-10-01

    Inadvertent perioperative hypothermia, a common occurrence in the operating suite, is associated with many adverse outcomes. It is the nurse anesthetist's goal to attenuate the incidence of this problem. Although active intraoperative warming is a widely accepted practice, active preoperative warming may be a less explored option for temperature maintenance. A search strategy to identify systematic reviews and investigations in peer-reviewed journals was undertaken to identify evidence examining the efficacy of preoperative warming. Evidence sources meeting the search criteria were randomized controlled trials and a cohort study using historical controls. Most of the studies support the implementation of active preoperative warming by demonstrating that subjects were warmer during the perioperative period. Overall, these differences were statistically significant and likely clinically significant. Future clinical trials should examine shorter warming times and lower warming unit settings, should include appropriate sample sizes, and should consistently employ trained staff using calibrated biometric instruments to measure temperature. PMID:24354070

  18. Endovascular Preoperative Embolization of Orbital Hemangiopericytoma With n-Butyl Cyanoacrylate Glue

    PubMed Central

    Wallace, Kaitlyn M.; Alaraj, Ali; Aakalu, Vinay K.; Aletich, Victor; Setabutr, Pete

    2014-01-01

    Hemangiopericytoma is an uncommon neoplasm that may present in myriad locations, including the lower extremities, pelvic area, and the head and neck area, including the orbit.1 Orbital hemangiopericytoma is often described as synonymous with orbital solitary fibrous tumor, giant cell angiofibroma, and fibrous histiocytoma, as they all belong to a spectrum of collagen-rich fibroblastic tumors that are often CD34-positive and have overlapping histopathologic features.2 Many cases of orbital hemangiopericytoma have been reported in the literature along with various surgical approaches, long-term outcomes, and techniques to manage recurrence; however, few have discussed preoperative embolization.1,3-5 Intraoperative hemorrhage is a concern in both the congenital and the adult form of these cases6,7 and may be an indication for preoperative embolization. A unique case of preoperative embolization was presented with n-butyl cyanoacrylate for surgical resection of a large orbital hemangiopericytoma in a 58-year-old woman. PMID:24317100

  19. Use of preoperative hypnosis to reduce postoperative pain and anesthesia-related side effects.

    PubMed

    Lew, Michael W; Kravits, Kathy; Garberoglio, Carlos; Williams, Anna Cathy

    2011-01-01

    The purpose of this pilot project was to test the feasibility of hypnosis as a preoperative intervention. The unique features of this study were: (a) use of a standardized nurse-delivered hypnosis protocol, (b) intervention administration immediately prior to surgery in the preoperative holding area, and (c) provision of hypnosis to breast cancer surgery patients receiving general anesthesia. A mixed-method design was used. Data collected from the intervention group and historical control group included demographics, symptom assessments, medication administration, and surgical, anesthesia, and recovery minutes. A semi-structured interview was conducted with the intervention group. A reduction in anxiety, worry, nervousness, sadness, irritability, and distress was found from baseline to postintervention while pain and nausea increased. The results support further exploration of the use of nurse-led preoperative hypnosis. PMID:21867377

  20. Selection of patients for preoperative coronary angiography: use of dipyridamole-stress--thallium myocardial imaging

    SciTech Connect

    Brewster, D.C.; Okada, R.D.; Strauss, H.W.; Abbott, W.M.; Darling, R.C.; Boucher, C.A.

    1985-05-01

    To identify patients likely to benefit from preoperative coronary angiography, a method utilizing pharmacologically induced coronary vasodilatation in conjunction with serial thallium 201 myocardial perfusion imaging was investigated. Fifty-four patients admitted for elective aortic or femoropopliteal procedures were studied. There were no cardiac ischemic complications in 32 patients with normal scans or persistent defects (scar). In contrast, 7 of 15 patients with thallium redistribution (ischemia) on pre-operative scanning had perioperative ischemic events, including one death and two acute infarcts. An additional seven patients with positive scans (redistribution) underwent coronary angiography prior to vascular surgery; surgically important two- or three-vessel disease was confirmed in all. Dipyridamole-thallium imaging facilitates selection of the subset of truly high-risk patients in whom preoperative coronary angiography may be warranted.

  1. Advantages of the Papillon protocol in the preoperative treatment of rectal carcinoma.

    PubMed

    Klimberg, V S; Langston, J D; Maners, A; Gocio, J C; Hutchins, L F; Lang, N P; Westbrook, K C; Broadwater, J R

    1992-11-01

    Standard treatment for advanced rectal carcinoma currently includes surgery, radiotherapy, and chemotherapy. Although there are theoretic advantages to preoperative irradiation, it is often not performed because of the prolonged delay of surgery and the purported increase in perioperative complications. A pilot study was undertaken at our institution to evaluate a treatment protocol advocated by Dr. Papillon that offers a shorter treatment time and less patient morbidity than conventional preoperative therapy for rectal carcinoma. Twenty patients with rectal cancer underwent the preoperative regimen that consisted of 3,000 cGy delivered in 10 fractions over 12 days with concomitant 5-fluorouracil and mitomycin-C. Complications were acceptable. Local recurrence was lower than in most reported trials, and survival rates were comparable. Additional benefits of the protocol include lower radiation morbidity to the patient and a decreased delay between diagnosis and surgery. PMID:1443366

  2. Accurate Thermal Stresses for Beams: Normal Stress

    NASA Technical Reports Server (NTRS)

    Johnson, Theodore F.; Pilkey, Walter D.

    2003-01-01

    Formulations for a general theory of thermoelasticity to generate accurate thermal stresses for structural members of aeronautical vehicles were developed in 1954 by Boley. The formulation also provides three normal stresses and a shear stress along the entire length of the beam. The Poisson effect of the lateral and transverse normal stresses on a thermally loaded beam is taken into account in this theory by employing an Airy stress function. The Airy stress function enables the reduction of the three-dimensional thermal stress problem to a two-dimensional one. Numerical results from the general theory of thermoelasticity are compared to those obtained from strength of materials. It is concluded that the theory of thermoelasticity for prismatic beams proposed in this paper can be used instead of strength of materials when precise stress results are desired.

  3. Accurate Thermal Stresses for Beams: Normal Stress

    NASA Technical Reports Server (NTRS)

    Johnson, Theodore F.; Pilkey, Walter D.

    2002-01-01

    Formulations for a general theory of thermoelasticity to generate accurate thermal stresses for structural members of aeronautical vehicles were developed in 1954 by Boley. The formulation also provides three normal stresses and a shear stress along the entire length of the beam. The Poisson effect of the lateral and transverse normal stresses on a thermally loaded beam is taken into account in this theory by employing an Airy stress function. The Airy stress function enables the reduction of the three-dimensional thermal stress problem to a two-dimensional one. Numerical results from the general theory of thermoelasticity are compared to those obtained from strength of materials. It is concluded that the theory of thermoelasticity for prismatic beams proposed in this paper can be used instead of strength of materials when precise stress results are desired.

  4. Highly accurate articulated coordinate measuring machine

    DOEpatents

    Bieg, Lothar F.; Jokiel, Jr., Bernhard; Ensz, Mark T.; Watson, Robert D.

    2003-12-30

    Disclosed is a highly accurate articulated coordinate measuring machine, comprising a revolute joint, comprising a circular encoder wheel, having an axis of rotation; a plurality of marks disposed around at least a portion of the circumference of the encoder wheel; bearing means for supporting the encoder wheel, while permitting free rotation of the encoder wheel about the wheel's axis of rotation; and a sensor, rigidly attached to the bearing means, for detecting the motion of at least some of the marks as the encoder wheel rotates; a probe arm, having a proximal end rigidly attached to the encoder wheel, and having a distal end with a probe tip attached thereto; and coordinate processing means, operatively connected to the sensor, for converting the output of the sensor into a set of cylindrical coordinates representing the position of the probe tip relative to a reference cylindrical coordinate system.

  5. Practical aspects of spatially high accurate methods

    NASA Technical Reports Server (NTRS)

    Godfrey, Andrew G.; Mitchell, Curtis R.; Walters, Robert W.

    1992-01-01

    The computational qualities of high order spatially accurate methods for the finite volume solution of the Euler equations are presented. Two dimensional essentially non-oscillatory (ENO), k-exact, and 'dimension by dimension' ENO reconstruction operators are discussed and compared in terms of reconstruction and solution accuracy, computational cost and oscillatory behavior in supersonic flows with shocks. Inherent steady state convergence difficulties are demonstrated for adaptive stencil algorithms. An exact solution to the heat equation is used to determine reconstruction error, and the computational intensity is reflected in operation counts. Standard MUSCL differencing is included for comparison. Numerical experiments presented include the Ringleb flow for numerical accuracy and a shock reflection problem. A vortex-shock interaction demonstrates the ability of the ENO scheme to excel in simulating unsteady high-frequency flow physics.

  6. The thermodynamic cost of accurate sensory adaptation

    NASA Astrophysics Data System (ADS)

    Tu, Yuhai

    2015-03-01

    Living organisms need to obtain and process environment information accurately in order to make decisions critical for their survival. Much progress have been made in identifying key components responsible for various biological functions, however, major challenges remain to understand system-level behaviors from the molecular-level knowledge of biology and to unravel possible physical principles for the underlying biochemical circuits. In this talk, we will present some recent works in understanding the chemical sensory system of E. coli by combining theoretical approaches with quantitative experiments. We focus on addressing the questions on how cells process chemical information and adapt to varying environment, and what are the thermodynamic limits of key regulatory functions, such as adaptation.

  7. Accurate numerical solutions of conservative nonlinear oscillators

    NASA Astrophysics Data System (ADS)

    Khan, Najeeb Alam; Nasir Uddin, Khan; Nadeem Alam, Khan

    2014-12-01

    The objective of this paper is to present an investigation to analyze the vibration of a conservative nonlinear oscillator in the form u" + lambda u + u^(2n-1) + (1 + epsilon^2 u^(4m))^(1/2) = 0 for any arbitrary power of n and m. This method converts the differential equation to sets of algebraic equations and solve numerically. We have presented for three different cases: a higher order Duffing equation, an equation with irrational restoring force and a plasma physics equation. It is also found that the method is valid for any arbitrary order of n and m. Comparisons have been made with the results found in the literature the method gives accurate results.

  8. Accurate Telescope Mount Positioning with MEMS Accelerometers

    NASA Astrophysics Data System (ADS)

    Mészáros, L.; Jaskó, A.; Pál, A.; Csépány, G.

    2014-08-01

    This paper describes the advantages and challenges of applying microelectromechanical accelerometer systems (MEMS accelerometers) in order to attain precise, accurate, and stateless positioning of telescope mounts. This provides a completely independent method from other forms of electronic, optical, mechanical or magnetic feedback or real-time astrometry. Our goal is to reach the subarcminute range which is considerably smaller than the field-of-view of conventional imaging telescope systems. Here we present how this subarcminute accuracy can be achieved with very cheap MEMS sensors and we also detail how our procedures can be extended in order to attain even finer measurements. In addition, our paper discusses how can a complete system design be implemented in order to be a part of a telescope control system.

  9. Accurate metacognition for visual sensory memory representations.

    PubMed

    Vandenbroucke, Annelinde R E; Sligte, Ilja G; Barrett, Adam B; Seth, Anil K; Fahrenfort, Johannes J; Lamme, Victor A F

    2014-04-01

    The capacity to attend to multiple objects in the visual field is limited. However, introspectively, people feel that they see the whole visual world at once. Some scholars suggest that this introspective feeling is based on short-lived sensory memory representations, whereas others argue that the feeling of seeing more than can be attended to is illusory. Here, we investigated this phenomenon by combining objective memory performance with subjective confidence ratings during a change-detection task. This allowed us to compute a measure of metacognition--the degree of knowledge that subjects have about the correctness of their decisions--for different stages of memory. We show that subjects store more objects in sensory memory than they can attend to but, at the same time, have similar metacognition for sensory memory and working memory representations. This suggests that these subjective impressions are not an illusion but accurate reflections of the richness of visual perception. PMID:24549293

  10. Apparatus for accurately measuring high temperatures

    DOEpatents

    Smith, Douglas D.

    1985-01-01

    The present invention is a thermometer used for measuring furnace temperaes in the range of about 1800.degree. to 2700.degree. C. The thermometer comprises a broadband multicolor thermal radiation sensor positioned to be in optical alignment with the end of a blackbody sight tube extending into the furnace. A valve-shutter arrangement is positioned between the radiation sensor and the sight tube and a chamber for containing a charge of high pressure gas is positioned between the valve-shutter arrangement and the radiation sensor. A momentary opening of the valve shutter arrangement allows a pulse of the high gas to purge the sight tube of air-borne thermal radiation contaminants which permits the radiation sensor to accurately measure the thermal radiation emanating from the end of the sight tube.

  11. Apparatus for accurately measuring high temperatures

    DOEpatents

    Smith, D.D.

    The present invention is a thermometer used for measuring furnace temperatures in the range of about 1800/sup 0/ to 2700/sup 0/C. The thermometer comprises a broadband multicolor thermal radiation sensor positioned to be in optical alignment with the end of a blackbody sight tube extending into the furnace. A valve-shutter arrangement is positioned between the radiation sensor and the sight tube and a chamber for containing a charge of high pressure gas is positioned between the valve-shutter arrangement and the radiation sensor. A momentary opening of the valve shutter arrangement allows a pulse of the high gas to purge the sight tube of air-borne thermal radiation contaminants which permits the radiation sensor to accurately measure the thermal radiation emanating from the end of the sight tube.

  12. Toward Accurate and Quantitative Comparative Metagenomics.

    PubMed

    Nayfach, Stephen; Pollard, Katherine S

    2016-08-25

    Shotgun metagenomics and computational analysis are used to compare the taxonomic and functional profiles of microbial communities. Leveraging this approach to understand roles of microbes in human biology and other environments requires quantitative data summaries whose values are comparable across samples and studies. Comparability is currently hampered by the use of abundance statistics that do not estimate a meaningful parameter of the microbial community and biases introduced by experimental protocols and data-cleaning approaches. Addressing these challenges, along with improving study design, data access, metadata standardization, and analysis tools, will enable accurate comparative metagenomics. We envision a future in which microbiome studies are replicable and new metagenomes are easily and rapidly integrated with existing data. Only then can the potential of metagenomics for predictive ecological modeling, well-powered association studies, and effective microbiome medicine be fully realized. PMID:27565341

  13. The importance of accurate atmospheric modeling

    NASA Astrophysics Data System (ADS)

    Payne, Dylan; Schroeder, John; Liang, Pang

    2014-11-01

    This paper will focus on the effect of atmospheric conditions on EO sensor performance using computer models. We have shown the importance of accurately modeling atmospheric effects for predicting the performance of an EO sensor. A simple example will demonstrated how real conditions for several sites in China will significantly impact on image correction, hyperspectral imaging, and remote sensing. The current state-of-the-art model for computing atmospheric transmission and radiance is, MODTRAN® 5, developed by the US Air Force Research Laboratory and Spectral Science, Inc. Research by the US Air Force, Navy and Army resulted in the public release of LOWTRAN 2 in the early 1970's. Subsequent releases of LOWTRAN and MODTRAN® have continued until the present. Please verify that (1) all pages are present, (2) all figures are correct, (3) all fonts and special characters are correct, and (4) all text and figures fit within the red margin lines shown on this review document. Complete formatting information is available at http://SPIE.org/manuscripts Return to the Manage Active Submissions page at http://spie.org/submissions/tasks.aspx and approve or disapprove this submission. Your manuscript will not be published without this approval. Please contact author_help@spie.org with any questions or concerns. The paper will demonstrate the importance of using validated models and local measured meteorological, atmospheric and aerosol conditions to accurately simulate the atmospheric transmission and radiance. Frequently default conditions are used which can produce errors of as much as 75% in these values. This can have significant impact on remote sensing applications.

  14. The high cost of accurate knowledge.

    PubMed

    Sutcliffe, Kathleen M; Weber, Klaus

    2003-05-01

    Many business thinkers believe it's the role of senior managers to scan the external environment to monitor contingencies and constraints, and to use that precise knowledge to modify the company's strategy and design. As these thinkers see it, managers need accurate and abundant information to carry out that role. According to that logic, it makes sense to invest heavily in systems for collecting and organizing competitive information. Another school of pundits contends that, since today's complex information often isn't precise anyway, it's not worth going overboard with such investments. In other words, it's not the accuracy and abundance of information that should matter most to top executives--rather, it's how that information is interpreted. After all, the role of senior managers isn't just to make decisions; it's to set direction and motivate others in the face of ambiguities and conflicting demands. Top executives must interpret information and communicate those interpretations--they must manage meaning more than they must manage information. So which of these competing views is the right one? Research conducted by academics Sutcliffe and Weber found that how accurate senior executives are about their competitive environments is indeed less important for strategy and corresponding organizational changes than the way in which they interpret information about their environments. Investments in shaping those interpretations, therefore, may create a more durable competitive advantage than investments in obtaining and organizing more information. And what kinds of interpretations are most closely linked with high performance? Their research suggests that high performers respond positively to opportunities, yet they aren't overconfident in their abilities to take advantage of those opportunities. PMID:12747164

  15. Accurate Weather Forecasting for Radio Astronomy

    NASA Astrophysics Data System (ADS)

    Maddalena, Ronald J.

    2010-01-01

    The NRAO Green Bank Telescope routinely observes at wavelengths from 3 mm to 1 m. As with all mm-wave telescopes, observing conditions depend upon the variable atmospheric water content. The site provides over 100 days/yr when opacities are low enough for good observing at 3 mm, but winds on the open-air structure reduce the time suitable for 3-mm observing where pointing is critical. Thus, to maximum productivity the observing wavelength needs to match weather conditions. For 6 years the telescope has used a dynamic scheduling system (recently upgraded; www.gb.nrao.edu/DSS) that requires accurate multi-day forecasts for winds and opacities. Since opacity forecasts are not provided by the National Weather Services (NWS), I have developed an automated system that takes available forecasts, derives forecasted opacities, and deploys the results on the web in user-friendly graphical overviews (www.gb.nrao.edu/ rmaddale/Weather). The system relies on the "North American Mesoscale" models, which are updated by the NWS every 6 hrs, have a 12 km horizontal resolution, 1 hr temporal resolution, run to 84 hrs, and have 60 vertical layers that extend to 20 km. Each forecast consists of a time series of ground conditions, cloud coverage, etc, and, most importantly, temperature, pressure, humidity as a function of height. I use the Liebe's MWP model (Radio Science, 20, 1069, 1985) to determine the absorption in each layer for each hour for 30 observing wavelengths. Radiative transfer provides, for each hour and wavelength, the total opacity and the radio brightness of the atmosphere, which contributes substantially at some wavelengths to Tsys and the observational noise. Comparisons of measured and forecasted Tsys at 22.2 and 44 GHz imply that the forecasted opacities are good to about 0.01 Nepers, which is sufficient for forecasting and accurate calibration. Reliability is high out to 2 days and degrades slowly for longer-range forecasts.

  16. Preoperative Pulmonary Rehabilitation before Lung Cancer Resection: Results from two Randomized Studies

    PubMed Central

    Benzo, Roberto; Wigle, Dennis; Novotny, Paul; Wetzstein, Marnie; Nichols, Francis; Shen, Robert K; Cassivi, Steve; Deschamps, Claude

    2011-01-01

    Complete surgical resection is the most effective curative treatment for lung cancer. However, many patients with lung cancer also have severe COPD which increases their risk of postoperative complications and their likelihood of being considered “inoperable.” Preoperative Pulmonary Rehabilitation (PR) has been proposed as an intervention to decrease surgical morbidity but there is no established protocol and no randomized study has been published to date. We tested two preoperative PR interventions in patients undergoing Lung Cancer resection and with moderate-severe COPD in a randomized single blinded design. Outcomes were length of hospital stay and postoperative complications. The first study tested 4 weeks of guideline-based PR vs.usual care: that study proved to be very difficult to recruit as patients and providers were reluctant to delay surgery. Nine patients were randomized and no differences were found between arms. The second study tested ten preoperative PR sessions using a customized protocol with nonstandard components (exercise prescription based on self efficacy, inspiratory muscle training, and the practice of slow breathing) (n=10) vs.usual care (N=9). The PR arm had shorter length of hospital stay by 3 days (p=0.058), fewer prolonged chest tubes (11% vs. 63%, p=0.03) and fewer days needing a chest tube (8.8vs.4.3 days p=0.04) compared to the controlled arm. A ten-session preoperative PR intervention may improve post operative lung reexpansion evidenced by shorter chest tube times and decrease the length of hospital stay, a crude estimator of post operative morbidity and costs. Our results suggest the potential for short term preoperative Pulmonary Rehabilitation interventions in patients with moderate-severe COPD undergoing curative lung resection. 4 weeks of conventional preoperative PR seems non feasible. PMID:21663994

  17. Preoperative Therapy for Lower Rectal Cancer and Modifications in Distance From Anal Sphincter

    SciTech Connect

    Gavioli, Margherita Losi, Lorena; Luppi, Gabriele; Iacchetta, Francesco; Zironi, Sandra; Bertolini, Federica; Falchi, Anna Maria; Bertoni, Filippo; Natalini, Gianni

    2007-10-01

    Purpose: To assess the frequency and magnitude of changes in lower rectal cancer resulting from preoperative therapy and its impact on sphincter-saving surgery. Preoperative therapy can increase the rate of preserving surgery by shrinking the tumor and enhancing its distance from the anal sphincter. However, reliable data concerning these modifications are not yet available in published reports. Methods and Materials: A total of 98 cases of locally advanced cancer of the lower rectum (90 Stage uT3-T4N0-N+ and 8 uT2N+M0) that had undergone preoperative therapy were studied by endorectal ultrasonography. The maximal size of the tumor and its distance from the anal sphincter were measured in millimeters before and after preoperative therapy. Surgery was performed 6-8 weeks after therapy, and the histopathologic margins were compared with the endorectal ultrasound data. Results: Of the 90 cases, 82.5% showed tumor downsizing, varying from one-third to two-thirds or more of the original tumor mass. The distance between the tumor and the anal sphincter increased in 60.2% of cases. The median increase was 0.73 cm (range, 0.2-2.5). Downsizing was not always associated with an increase in distance. Preserving surgery was performed in 60.6% of cases. It was possible in nearly 30% of patients in whom the cancer had reached the anal sphincter before the preoperative therapy. The distal margin was tumor free in these cases. Conclusion: The results of our study have shown that in very low rectal cancer, preoperative therapy causes tumor downsizing in >80% of cases and in more than one-half enhances the distance between the tumor and anal sphincter. These modifications affect the primary surgical options, facilitating or making sphincter-saving surgery possible.

  18. The role of preoperative ultrasonography, computed tomography, and sestamibi scintigraphy localization in secondary hyperparathyroidism

    PubMed Central

    Lee, Jae Bok; Kim, Woo Young

    2015-01-01

    Purpose The role of preoperative localization studies is controversial in surgery of secondary hyperparathyroidism (sHPT). The aim of study was to evaluate the accuracy of preoperative ultrasonography (USG), CT, and 99mTc sestamibi scintigraphy (MIBI) in localizing enlarged parathyroid glands and to find the impact of correct localization in successful parathyroidectomy. Methods We compared operative findings with the preoperative localization of ultrasonography, computerized tomography and sestamibi scintigraphy in 109 patients with sHPT and identified well-visualized locations of abnormal parathyroid glands by evaluating the sensitivity of each imaging study with regard to typical locations of glands. We investigated the effect of preoperative imaging localization on the surgical outcomes by measuring the intraoperative parathyroid hormone (ioPTH) decrement for positive or negative imaging localization. Results USG (91.5%) had the highest sensitivity and MIBI (56.1%) had the lowest among 3 modalities. The sensitivity of combined USG and CT (95.0%) was the highest among combined 2 modalities. The combination of all 3 modalities (95.4%) had the highest sensitivity among the combinations of modalities. The reduction of ioPTH in patients with positive imaging localization (86.6%) was greater than negative imaging localization (84.2%), with no significant difference (P = 0.586). The recurrence or persistence of sHPT was not correlated with preoperative imaging localization (19 patients in negative, 16 in positive; P = 0.14). Conclusion Preoperative imaging localization contributed to surgical success but not to surgical outcomes. The combination of ioPTH measurement with imaging localization might be valuable for better surgical results in sHPT. PMID:26665124

  19. Is preoperative hepatic arterial chemoembolization safe and effective for hepatocellular carcinoma?

    PubMed Central

    Harada, T; Matsuo, K; Inoue, T; Tamesue, S; Inoue, T; Nakamura, H

    1996-01-01

    OBJECTIVE. The value of preoperative transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) has not been duly appreciated. The authors assessed the advantages and disadvantages of preoperative TACE by reviewing their experience with the procedure. METHODS. A total of 140 patients who underwent hepatectomy for HCC were entered into the study (105 received preoperative TACE and 35 did not). The authors investigated the reduction of tumor size and the complications after TACE, as well as the relationship between the interval from TACE to resection and the occurrence of complications. They compared postoperative morbidity and mortality between the TACE and non-TACE groups. They also compared survival and disease-free survival between the two groups, as well as between subgroups, defined by the extent of tumor necrosis achieved with TACE. RESULTS. A distinct reduction of tumor size was observed in approximately half of the TACE group. However, there were 68 appreciable complications of TACE in 56 patients (53.3%), and the interval between TACE and resection was significantly prolonged in the patients with complications. The postoperative morbidity and mortality rates of the TACE group were not different from those of the non-TACE group. Preoperative TACE did not improve the survival or disease-free survival of the whole patient group after hepatectomy. In addition, the survival and disease-free survival rates of the three TACE subgroups were not different from those of the non-TACE group. CONCLUSIONS. Preoperative TACE should only be performed to reduce tumor bulk in patients with HCC with borderline resectability. In such patients, increased tumor resectability appears to improve the survival rate. Preoperative TACE does not promote tumor recurrence. PMID:8678616

  20. Preoperative Low Serum Bicarbonate Levels Predict Acute Kidney Injury After Cardiac Surgery.

    PubMed

    Jung, Su-Young; Park, Jung Tak; Kwon, Young Eun; Kim, Hyung Woo; Ryu, Geun Woo; Lee, Sul A; Park, Seohyun; Jhee, Jong Hyun; Oh, Hyung Jung; Han, Seung Hyeok; Yoo, Tae-Hyun; Kang, Shin-Wook

    2016-03-01

    Acute kidney injury (AKI) after cardiac surgery is a common and serious complication. Although lower than normal serum bicarbonate levels are known to be associated with consecutive renal function deterioration in patients with chronic kidney injury, it is not well-known whether preoperative low serum bicarbonate levels are associated with the development of AKI in patients who undergo cardiac surgery. Therefore, the clinical implication of preoperative serum bicarbonate levels on AKI occurrence after cardiac surgery was investigated. Patients who underwent coronary artery bypass or valve surgery at Yonsei University Health System from January 2013 to December 2014 were enrolled. The patients were divided into 3 groups based on preoperative serum bicarbonate levels, which represented group 1 (below normal levels) <23 mEq/L; group 2 (normal levels) 23 to 24 mEq/L; and group 3 (elevated levels) >24 mEq/L. The primary outcome was the predicated incidence of AKI 48 hours after cardiac surgery. AKI was defined according to Acute Kidney Injury Network criteria. Among 875 patients, 228 (26.1%) developed AKI within 48 hours after cardiac surgery. The incidence of AKI was higher in group 1 (40.9%) than in group 2 (26.5%) and group 3 (19.5%) (P < 0.001). In addition, the duration of postoperative stay in a hospital intensive care unit (ICU) was longer for AKI patients and for those in the low-preoperative-serum-bicarbonate-level groups. A multivariate logistic regression analysis showed that low preoperative serum bicarbonate levels were significantly associated with AKI even after adjustment for age, sex, hypertension, diabetes mellitus, operation type, preoperative hemoglobin, and estimated glomerular filtration rate. In conclusion, low serum bicarbonate levels were associated with higher incidence of AKI and prolonged ICU stay. Further studies are needed to clarify whether strict correction of bicarbonate levels close to normal limits may have a protective

  1. Radioguided localisation of impalpable breast lesions using 99m-Technetium macroaggregated albumin: Lessons learnt during introduction of a new technique to guide preoperative localisation

    SciTech Connect

    Landman, Joanne; Kulawansa, Sagarika; McCarthy, Michael; Troedson, Russell; Phillips, Michael; Tinning, Jill; Taylor, Donna

    2015-03-15

    Preoperative wire-guided localisation (WGL) of impalpable breast lesions is widely used but can be technically difficult. Risks include wire migration, inaccurate placement, and inadequate surgical margins. Research shows that radioguided occult lesion localisation (ROLL) is quicker, easier, and can improve surgical and cosmetic outcomes. An audited introduction of ROLL was conducted to validate the technique as a feasible alternative to WGL. Fifty patients with single impalpable lesions and biopsy proven malignancy or indeterminate histology underwent WGL followed by intralesional radiopharmaceutical injection of 99m-Technetium macroaggregated albumin. Postprocedural mammography was performed to demonstrate wire position, and scintigraphy to evaluate radiopharmaceutical migration. Lymphoscintigraphy and intraoperative sentinel node biopsy were performed if indicated, followed by lesion localisation and excision using a gamma probe. Specimen imaging was performed, with immediate reexcision for visibly inadequate margins. Accurate localisation was achieved in 86% of patients with ROLL compared to 72% with WGL. All lesions were successfully removed, with clear margins in 71.8% of malignant lesions. Reexcision and intraoperative sentinel node localisation rates were equivalent to preaudit figures for WGL. ROLL was easy to perform and problems were infrequent. Inaccurate radiopharmaceutical placement necessitating WGL occurred in four patients. Minor radiopharmaceutical migration was common, but precluded using ROLL in only two cases. ROLL is effective, simple, inexpensive, and easily learnt; however, preoperative confirmation of correct radiopharmaceutical placement using mammography and the gamma probe is important to help ensure successful lesion removal. Insertion of a backup hookwire is recommended during the initial introduction of ROLL.

  2. Use of preoperative localization of adenomas of the parathyroid glands by thallium-technetium subtraction scintigraphy, high-resolution ultrasonography and computed tomography

    SciTech Connect

    Roses, D.F.; Sudarsky, L.A.; Sanger, J.; Raghavendra, B.N.; Reede, D.L.; Blum, M.

    1989-02-01

    Thirty-six patients with primary hyperparathyroidism were studied preoperatively by thallium-201 and technetium-99m pertechnetate subtraction (Tl-201/Tc-99m) scintigraphy, high-resolution real time ultrasonography and computed tomographic (CT) scanning. None of the patients had had previous surgical treatment of the parathyroid or thyroid glands. All of the patients underwent systematic bilateral exploration of the neck. All of the patients were successfully explored and 41 abnormal parathyroid glands were identified. Five patients had two adenomas. In six instances, adenomas were identified in ectopic anatomic sites. The sensitivity of correctly localizing the abnormal glands with these techniques was 49 per cent for the Tl-201/Tc-99m scintigraphy, 34 per cent for ultrasonography and 41 per cent for CT scanning. The Tl-201/Tc-99m scintigrams detected two of the six ectopically located adenomas, CT detected one, while ultrasound detected none. The five patients with multiple adenomas were not accurately identified as having multiple gland enlargement by any of these studies. Therefore, preoperative localization studies with these three techniques did not provide reliable information for initial bilateral exploration of the neck.

  3. Complications associated with preoperative radiation therapy and Iodine-125 brachytherapy for localized prostatic carcinoma

    SciTech Connect

    Flanigan, R.C.; Patterson, J.; Mendiondo, O.A.; Gee, W.F.; Lucas, B.A.; McRoberts, J.W.

    1983-08-01

    Twenty-five consecutive patients with localized adenocarcinoma of the prostate treated with 1,050 rad preoperative radiation therapy and Iodine-125 seed brachytherapy are reviewed. Significant long-term postoperative complications included radiation cystitis (12%), radiation proctitis (4%), genital and leg edema (12%), stress incontinence (8%), total incontinence (4%), and impotence (26%). Complications occurred in 75 per cent of patients who received additional postoperative radiation. Improved staging with CT scan, lymphangiography, and Chiba needle biopsy of any possibly abnormal lymph nodes provided excellent preoperative staging with only 1 patient (6%) upstaged at surgery to Stage D1.

  4. Computed tomography evaluation of the adrenal gland in the preoperative assessment of bronchogenic carcinoma

    SciTech Connect

    Sandler, M.A.; Pearlberg, J.L.; Madrazo, B.L.; Gitschlag, K.F.; Gross, S.C.

    1982-12-01

    One hundred ten patients with proved bronchogenic carcinoma who were undergoing computed tomography (CT) of the thorax also underwent CT of the adrenals to determine the value of routine preoperative assessement of this gland. Sixteen adrenal masses were found in 11 patients. In five patients the adrenals were the only site of metastasis. CT of the adrenals should be performed routinely when the thorax is examined pre-operatively in patients with non-oat-cell bronchogenic carcinoma to improve patient selection for thoractomy.

  5. Role of preoperative screening for adult patients for obstructive sleep apnea.

    PubMed

    Selim, Bernardo J; Surani, Salim R; Ramar, Kannan

    2014-12-01

    Obstructive sleep apnea (OSA) is a chronic disease with increasing prevalence. Underdiagnosed in the surgical population, OSA can reach a prevalence of up to 70% in bariatric surgery, and be associated with difficult airways and postoperative cardiopulmonary adverse events. Despite its association with escalation of care, increased health care resource utilization, and length of hospital stay, < 25% of health care institutions in the United States have OSA perioperative protocols to improve patient safety. This is explained in part by a lack of studies that support a widely accepted systematic approach to preoperative screening and risk stratification. This review evaluates the role of preoperative screening tools for adult patients with suspected OSA. PMID:25485922

  6. [Update on current care guidelines: acute respiratory failure--preoperative evaluation].

    PubMed

    2014-01-01

    Concomitant diseases, the patient's general condition, exercise capacity and the extent of surgery are determinants of the operative risk. Increasing number of patients with endovascular stents and antithrombotic medication need special perioperative precautions as well as the eventual endocarditis prophylaxis. The risk of perioperative complications can probably be decreased by respiratory physiotherapy, correction of anaemia and smoking cessation. Severe liver or kidney insufficiency need be evaluated. Principles of preoperative fasting and perioperative strategies with concomitant medication are described, and use of preoperative carbohydrate drinks are encouraged. PMID:25272790

  7. Respiratory physiotherapy and its application in preoperative period of cardiac surgery.

    PubMed

    Miranda, Regina Coeli Vasques de; Padulla, Susimary Aparecida Trevizan; Bortolatto, Carolina Rodrigues

    2011-01-01

    Cardiac surgical procedures change respiratory mechanics, defecting in lung dysfunction. The physical therapists play an important role in the preparation and rehabilitation of individuals who are undergoing cardiac surgery, as they have a large quantity of techniques. The objective was to evaluate the effectiveness of breathing exercises with and without the use of devices, and respiratory muscle training in preoperative period of cardiac surgery in reducing postoperative pulmonary complications. Although there are controversies as to which technique to use, studies show the effectiveness of preoperative physiotherapy in the prevention and reduction of postoperative pulmonary complications. PMID:22358282

  8. Stage I carcinoma of the endometrium: a 5-year experience utilizing preoperative cesium

    SciTech Connect

    Belinson, J.L.; Spirou, B.; McClure, M.; Badger, G.; Pretorius, R.G.; Roland, T.A.

    1985-03-01

    A treatment protocol for the management of stage I endometrial carcinoma utilizing preoperative cesium is evaluated. One hundred and twelve consecutive patients were treated according to this protocol over a 5-year period. Based on this experience and a literature review a new protocol is recommended. The significant changes include primary surgery without preoperative cesium, primary treatment based on grade without regard to uterine size, modified radical hysterectomy for G3 tumors, pelvic radiotherapy for clear cell carcinoma confined to the pelvis regardless of depth of invasion, cytoxan, adriamycin, and cis-platinum for papillary serous tumors, and postoperative vaginal cuff cesium for G2 and G3 tumors not requiring pelvic radiotherapy.

  9. Routine use of preoperative breast MRI for patients considered for intraoperative radiotherapy

    PubMed Central

    Small, William; Emami, Bahman

    2016-01-01

    This editorial comments on the study by Tallet et al. which reported on the incidence of ipsilateral second breast cancers (BC) detected by preoperative magnetic resonance imaging (MRI) in patients being considered for intraoperative radiotherapy (IORT). Any second BC was detected in 7% of patients; an ipsilateral BC was detected in 4% of patients, precluding them from IORT. The authors comment that in view of detection of a substantial rate of ipsilateral BCs by preoperative MRI, this exam should be used routinely for staging patients being considered for IORT. PMID:27162648

  10. Interictal epileptiform discharge effects on neuropsychological assessment and epilepsy surgical planning.

    PubMed

    Drane, Daniel L; Ojemann, Jeffrey G; Kim, Michelle S; Gross, Robert E; Miller, John W; Faught, R Edward; Loring, David W

    2016-03-01

    Both animal research and human research suggest that interictal epileptiform discharges (IEDs) may affect cognition, although the significance of such findings remains controversial. We review a wide range of literature with bearing on this topic and present relevant epilepsy surgery cases, which suggest that the effects of IEDs may be substantial and informative for surgical planning. In the first case, we present a patient with epilepsy with left anterior temporal lobe (TL) seizure onset who experienced frequent IEDs during preoperative neuropsychological assessment. Cognitive results strongly lateralized to the left TL. Because the patient failed performance validity tests and appeared amnestic for verbal materials inconsistent with his work history, selected neuropsychological tests were repeated 6 weeks later. Scores improved one to two standard deviations over the initial evaluation and because of this improvement, were only mildly suggestive of left TL impairment. The second case involves another patient with documented left TL epilepsy who experienced epileptiform activity while undergoing neurocognitive testing and simultaneous ambulatory EEG recording. This patient's verbal memory performance was impaired during the period that IEDs were present but near normal when such activity was absent. Overall, although the presence of IEDs may be helpful in confirming laterality of seizure onset, frequent IEDs might disrupt focal cognitive functions and distort accurate measurement of neuropsychological ability, interfering with accurate characterization of surgical risks and benefits. Such transient effects on daily performance may also contribute to significant functional compromise. We include a discussion of the manner in which IED effects during presurgical assessment can hinder individual patient presurgical planning as well as distort outcome research (e.g., IEDs occurring during presurgical assessment may lead to an underestimation of postoperative

  11. Approaching system equilibrium with accurate or not accurate feedback information in a two-route system

    NASA Astrophysics Data System (ADS)

    Zhao, Xiao-mei; Xie, Dong-fan; Li, Qi

    2015-02-01

    With the development of intelligent transport system, advanced information feedback strategies have been developed to reduce traffic congestion and enhance the capacity. However, previous strategies provide accurate information to travelers and our simulation results show that accurate information brings negative effects, especially in delay case. Because travelers prefer to the best condition route with accurate information, and delayed information cannot reflect current traffic condition but past. Then travelers make wrong routing decisions, causing the decrease of the capacity and the increase of oscillations and the system deviating from the equilibrium. To avoid the negative effect, bounded rationality is taken into account by introducing a boundedly rational threshold BR. When difference between two routes is less than the BR, routes have equal probability to be chosen. The bounded rationality is helpful to improve the efficiency in terms of capacity, oscillation and the gap deviating from the system equilibrium.

  12. Preoperative Ultrasound Guided Fine Needle Aspiration Cytology of Ovarian Lesions- Is It a Rapid and Effective Diagnostic Modality?

    PubMed Central

    Datta, Saikat; Chaudhuri, Snehamay; Paul, Prabir Chandra; Khandakar, Binny; Mandal, Sonali

    2016-01-01

    Introduction The deep seated ovarian lesions unapproachable by unguided aspiration cytology were easily done under ultrasound guidance. It gave a before hand cytological diagnosis of the lesion to the surgeon determining the modality of treatment for the patient. Aim To find the diagnostic accuracy of the method of ultrasound guided cytological assessment of ovarian lesion. Materials and Methods The study was conducted as a prospective observational study over a period of one year, in hospital setting, where ultrasound guided fine needle aspiration had been used to aspirate ovarian lesions, giving a rapid cytological diagnosis. In 43 sample cases, aspiration of fluid done from ovarian lesions were followed by cyto-centrifugation and staining by May-Grunwald-Giemsa (MGG) and Papanicolaou (Pap) stain providing a cytological opinion regarding benign/malignant nature of the lesion and further categorization. Later the cytological diagnosis was compared with final histopathological diagnosis, taking it as a gold standard. Results The overall sensitivity, specificity, and diagnostic accuracy of ultrasound guided aspiration and cytological analysis were high, 96%, 76.92% and 89.47% respectively as calculated by comparing the cytological diagnosis with histological diagnosis, taking it as gold standard. Conclusion This method has evolved as a highly sensitive, rapid, simple and effective modality for screening and as well as accurate preoperative diagnosis of ovarian lesions. PMID:27134878

  13. Higher order accurate partial implicitization: An unconditionally stable fourth-order-accurate explicit numerical technique

    NASA Technical Reports Server (NTRS)

    Graves, R. A., Jr.

    1975-01-01

    The previously obtained second-order-accurate partial implicitization numerical technique used in the solution of fluid dynamic problems was modified with little complication to achieve fourth-order accuracy. The Von Neumann stability analysis demonstrated the unconditional linear stability of the technique. The order of the truncation error was deduced from the Taylor series expansions of the linearized difference equations and was verified by numerical solutions to Burger's equation. For comparison, results were also obtained for Burger's equation using a second-order-accurate partial-implicitization scheme, as well as the fourth-order scheme of Kreiss.

  14. A survey among Brazilian thoracic surgeons about the use of preoperative 2D and 3D images

    PubMed Central

    Cipriano, Federico Enrique Garcia; Arcêncio, Livia; Dessotte, Lycio Umeda; Rodrigues, Alfredo José; Vicente, Walter Villela de Andrade

    2016-01-01

    Background Describe the characteristics of how the thoracic surgeon uses the 2D/3D medical imaging to perform surgical planning, clinical practice and teaching in thoracic surgery and check the initial choice and the final choice of the Brazilian Thoracic surgeon as the 2D and 3D models pictures before and after acquiring theoretical knowledge on the generation, manipulation and interactive 3D views. Methods A descriptive research type Survey cross to data provided by the Brazilian Thoracic Surgeons (members of the Brazilian Society of Thoracic Surgery) who responded to the online questionnaire via the internet on their computers or personal devices. Results Of the 395 invitations visualized distributed by email, 107 surgeons completed the survey. There was no statically difference when comparing the 2D vs. 3D models pictures for the following purposes: diagnosis, assessment of the extent of disease, preoperative surgical planning, and communication among physicians, resident training, and undergraduate medical education. Regarding the type of tomographic image display routinely used in clinical practice (2D or 3D or 2D–3D model image) and the one preferred by the surgeon at the end of the questionnaire. Answers surgeons for exclusive use of 2D images: initial choice =50.47% and preferably end =14.02%. Responses surgeons to use 3D models in combination with 2D images: initial choice =48.60% and preferably end =85.05%. There was a significant change in the final selection of 3D models used together with the 2D images (P<0.0001). Conclusions There is a lack of knowledge of the 3D imaging, as well as the use and interactive manipulation in dedicated 3D applications, with consequent lack of uniformity in the surgical planning based on CT images. These findings certainly confirm in changing the preference of thoracic surgeons of 2D views of technologies for 3D images. PMID:27621874

  15. Preoperative Short-Course Concurrent Chemoradiation Therapy Followed by Delayed Surgery for Locally Advanced Rectal Cancer: A Phase 2 Multicenter Study (KROG 10-01)

    SciTech Connect

    Yeo, Seung-Gu; Oh, Jae Hwan; Kim, Dae Yong; Baek, Ji Yeon; Kim, Sun Young; Park, Ji Won; Kim, Min Ju; Chang, Hee Jin; Kim, Tae Hyun; Lee, Jong Hoon; Jang, Hong Seok; Kim, Jun-Gi; Lee, Myung Ah; Nam, Taek-Keun

    2013-05-01

    Purpose: A prospective phase 2 multicenter trial was performed to investigate the efficacy and safety of preoperative short-course concurrent chemoradiation therapy (CRT) followed by delayed surgery for patients with locally advanced rectal cancer. Methods and Materials: Seventy-three patients with cT3-4 rectal cancer were enrolled. Radiation therapy of 25 Gy in 5 fractions was delivered over 5 consecutive days using helical tomotherapy. Concurrent chemotherapy was administered on the same 5 days with intravenous bolus injection of 5-fluorouracil (400 mg/m{sup 2}/day) and leucovorin (20 mg/m{sup 2}/day). After 4 to 8 weeks, total mesorectal excision was performed. The primary endpoint was the pathologic downstaging (ypStage 0-I) rate, and secondary endpoints included tumor regression grade, tumor volume reduction rate, and toxicity. Results: Seventy-one patients completed the planned preoperative CRT and surgery. Downstaging occurred in 20 (28.2%) patients, including 1 (1.4%) with a pathologic complete response. Favorable tumor regression (grade 4-3) was observed in 4 (5.6%) patients, and the mean tumor volume reduction rate was 62.5 ± 21.3%. Severe (grade ≥3) treatment toxicities were reported in 27 (38%) patients from CRT until 3 months after surgery. Conclusions: Preoperative short-course concurrent CRT followed by delayed surgery for patients with locally advanced rectal cancer demonstrated poor pathologic responses compared with conventional long-course CRT, and it yielded considerable toxicities despite the use of an advanced radiation therapy technique.

  16. Preoperative evaluation of peripheral nerve injuries: What is the place for ultrasound?

    PubMed

    Toia, Francesca; Gagliardo, Andrea; D'Arpa, Salvatore; Gagliardo, Cesare; Gagliardo, Giuseppe; Cordova, Adriana

    2016-09-01

    OBJECTIVE The purpose of this study was to evaluate the usefulness of ultrasound in the preoperative workup of peripheral nerve lesions and illustrate how nerve ultrasonography can be integrated in routine clinical and neurophysiological evaluation and in the management of focal peripheral nerve injuries. The diagnostic role and therapeutic implications of ultrasonography for different neuropathies are described. METHODS The authors analyzed the use of ultrasound in 119 entrapment, tumoral, posttraumatic, or postsurgical nerve injuries of limbs evaluated in 108 patients during 2013 and 2014. All patients were candidates for surgery, and in all cases the evaluation included clinical examination, electrodiagnostic studies (nerve conduction study and electromyography), and ultrasound nerve study. Ultrasound was used to explore the nerve fascicular echotexture, continuity, and surrounding tissues. The maximum cross-sectional area (CSA) and the presence of epineurial hyperechogenicity or intraneural hyper- or hypoechogenicity, of anatomical anomalies, dynamic nerve dislocations, or compressions were recorded. The concordance rate of neurophysiological and ultrasonographic data was analyzed, classifying ultrasound findings as confirming, contributive, or nonconfirming with respect to electrodiagnostic data. The correlation between maximum nerve CSA and neurophysiological severity degree in entrapment syndromes was statistically analyzed. RESULTS Ultrasonography confirmed electrodiagnostic findings in 36.1% of cases and showed a contributive role in the diagnosis and surgical planning in 53.8% of all cases; the findings were negative ("nonconfirming") in only 10.1% of the patients. In 16% of cases, ultrasound was not only contributive, but had a key diagnostic role in the presence of doubtful electrodiagnostic findings. The contributive role differed according to etiology, being higher for tumors (100%) and for posttraumatic or postsurgical neuropathies (72.2%) than for

  17. TWRS phase I privatization site environmental baseline and characterization plan

    SciTech Connect

    Shade, J.W.

    1997-09-01

    This document provides a plan to characterize and develop an environmental baseline for the TWRS Phase I Privatization Site before construction begins. A site evaluation study selected the former Grout Disposal Area of the Grout Treatment Facility in the 200 East Area as the TWRS Phase I Demonstration Site. The site is generally clean and has not been used for previous activities other than the GTF. A DQO process was used to develop a Sampling and Analysis Plan that would allow comparison of site conditions during operations and after Phase I ends to the presently existing conditions and provide data for the development of a preoperational monitoring plan.

  18. GPU-accelerated interactive visualization and planning of neurosurgical interventions.

    PubMed

    Rincón-Nigro, Mario; Navkar, Nikhil V; Tsekos, Nikolaos V; Zhigang Deng

    2014-01-01

    Advances in computational methods and hardware platforms provide efficient processing of medical-imaging datasets for surgical planning. For neurosurgical interventions employing a straight access path, planning entails selecting a path from the scalp to the target area that's of minimal risk to the patient. A proposed GPU-accelerated method enables interactive quantitative estimation of the risk for a particular path. It exploits acceleration spatial data structures and efficient implementation of algorithms on GPUs. In evaluations of its computational efficiency and scalability, it achieved interactive rates even for high-resolution meshes. A user study and feedback from neurosurgeons identified this methods' potential benefits for preoperative planning and intraoperative replanning. PMID:24808165

  19. Accurate Fission Data for Nuclear Safety

    NASA Astrophysics Data System (ADS)

    Solders, A.; Gorelov, D.; Jokinen, A.; Kolhinen, V. S.; Lantz, M.; Mattera, A.; Penttilä, H.; Pomp, S.; Rakopoulos, V.; Rinta-Antila, S.

    2014-05-01

    The Accurate fission data for nuclear safety (AlFONS) project aims at high precision measurements of fission yields, using the renewed IGISOL mass separator facility in combination with a new high current light ion cyclotron at the University of Jyväskylä. The 30 MeV proton beam will be used to create fast and thermal neutron spectra for the study of neutron induced fission yields. Thanks to a series of mass separating elements, culminating with the JYFLTRAP Penning trap, it is possible to achieve a mass resolving power in the order of a few hundred thousands. In this paper we present the experimental setup and the design of a neutron converter target for IGISOL. The goal is to have a flexible design. For studies of exotic nuclei far from stability a high neutron flux (1012 neutrons/s) at energies 1 - 30 MeV is desired while for reactor applications neutron spectra that resembles those of thermal and fast nuclear reactors are preferred. It is also desirable to be able to produce (semi-)monoenergetic neutrons for benchmarking and to study the energy dependence of fission yields. The scientific program is extensive and is planed to start in 2013 with a measurement of isomeric yield ratios of proton induced fission in uranium. This will be followed by studies of independent yields of thermal and fast neutron induced fission of various actinides.

  20. Fast and Provably Accurate Bilateral Filtering

    NASA Astrophysics Data System (ADS)

    Chaudhury, Kunal N.; Dabhade, Swapnil D.

    2016-06-01

    The bilateral filter is a non-linear filter that uses a range filter along with a spatial filter to perform edge-preserving smoothing of images. A direct computation of the bilateral filter requires $O(S)$ operations per pixel, where $S$ is the size of the support of the spatial filter. In this paper, we present a fast and provably accurate algorithm for approximating the bilateral filter when the range kernel is Gaussian. In particular, for box and Gaussian spatial filters, the proposed algorithm can cut down the complexity to $O(1)$ per pixel for any arbitrary $S$. The algorithm has a simple implementation involving $N+1$ spatial filterings, where $N$ is the approximation order. We give a detailed analysis of the filtering accuracy that can be achieved by the proposed approximation in relation to the target bilateral filter. This allows us to to estimate the order $N$ required to obtain a given accuracy. We also present comprehensive numerical results to demonstrate that the proposed algorithm is competitive with state-of-the-art methods in terms of speed and accuracy.

  1. Accurate Prediction of Docked Protein Structure Similarity.

    PubMed

    Akbal-Delibas, Bahar; Pomplun, Marc; Haspel, Nurit

    2015-09-01

    One of the major challenges for protein-protein docking methods is to accurately discriminate nativelike structures. The protein docking community agrees on the existence of a relationship between various favorable intermolecular interactions (e.g. Van der Waals, electrostatic, desolvation forces, etc.) and the similarity of a conformation to its native structure. Different docking algorithms often formulate this relationship as a weighted sum of selected terms and calibrate their weights against specific training data to evaluate and rank candidate structures. However, the exact form of this relationship is unknown and the accuracy of such methods is impaired by the pervasiveness of false positives. Unlike the conventional scoring functions, we propose a novel machine learning approach that not only ranks the candidate structures relative to each other but also indicates how similar each candidate is to the native conformation. We trained the AccuRMSD neural network with an extensive dataset using the back-propagation learning algorithm. Our method achieved predicting RMSDs of unbound docked complexes with 0.4Å error margin. PMID:26335807

  2. Accurate lineshape spectroscopy and the Boltzmann constant

    PubMed Central

    Truong, G.-W.; Anstie, J. D.; May, E. F.; Stace, T. M.; Luiten, A. N.

    2015-01-01

    Spectroscopy has an illustrious history delivering serendipitous discoveries and providing a stringent testbed for new physical predictions, including applications from trace materials detection, to understanding the atmospheres of stars and planets, and even constraining cosmological models. Reaching fundamental-noise limits permits optimal extraction of spectroscopic information from an absorption measurement. Here, we demonstrate a quantum-limited spectrometer that delivers high-precision measurements of the absorption lineshape. These measurements yield a very accurate measurement of the excited-state (6P1/2) hyperfine splitting in Cs, and reveals a breakdown in the well-known Voigt spectral profile. We develop a theoretical model that accounts for this breakdown, explaining the observations to within the shot-noise limit. Our model enables us to infer the thermal velocity dispersion of the Cs vapour with an uncertainty of 35 p.p.m. within an hour. This allows us to determine a value for Boltzmann's constant with a precision of 6 p.p.m., and an uncertainty of 71 p.p.m. PMID:26465085

  3. Fast and Provably Accurate Bilateral Filtering.

    PubMed

    Chaudhury, Kunal N; Dabhade, Swapnil D

    2016-06-01

    The bilateral filter is a non-linear filter that uses a range filter along with a spatial filter to perform edge-preserving smoothing of images. A direct computation of the bilateral filter requires O(S) operations per pixel, where S is the size of the support of the spatial filter. In this paper, we present a fast and provably accurate algorithm for approximating the bilateral filter when the range kernel is Gaussian. In particular, for box and Gaussian spatial filters, the proposed algorithm can cut down the complexity to O(1) per pixel for any arbitrary S . The algorithm has a simple implementation involving N+1 spatial filterings, where N is the approximation order. We give a detailed analysis of the filtering accuracy that can be achieved by the proposed approximation in relation to the target bilateral filter. This allows us to estimate the order N required to obtain a given accuracy. We also present comprehensive numerical results to demonstrate that the proposed algorithm is competitive with the state-of-the-art methods in terms of speed and accuracy. PMID:27093722

  4. How Accurate are SuperCOSMOS Positions?

    NASA Astrophysics Data System (ADS)

    Schaefer, Adam; Hunstead, Richard; Johnston, Helen

    2014-02-01

    Optical positions from the SuperCOSMOS Sky Survey have been compared in detail with accurate radio positions that define the second realisation of the International Celestial Reference Frame (ICRF2). The comparison was limited to the IIIaJ plates from the UK/AAO and Oschin (Palomar) Schmidt telescopes. A total of 1 373 ICRF2 sources was used, with the sample restricted to stellar objects brighter than BJ = 20 and Galactic latitudes |b| > 10°. Position differences showed an rms scatter of 0.16 arcsec in right ascension and declination. While overall systematic offsets were < 0.1 arcsec in each hemisphere, both the systematics and scatter were greater in the north.

  5. Accurate adiabatic correction in the hydrogen molecule

    SciTech Connect

    Pachucki, Krzysztof; Komasa, Jacek

    2014-12-14

    A new formalism for the accurate treatment of adiabatic effects in the hydrogen molecule is presented, in which the electronic wave function is expanded in the James-Coolidge basis functions. Systematic increase in the size of the basis set permits estimation of the accuracy. Numerical results for the adiabatic correction to the Born-Oppenheimer interaction energy reveal a relative precision of 10{sup −12} at an arbitrary internuclear distance. Such calculations have been performed for 88 internuclear distances in the range of 0 < R ⩽ 12 bohrs to construct the adiabatic correction potential and to solve the nuclear Schrödinger equation. Finally, the adiabatic correction to the dissociation energies of all rovibrational levels in H{sub 2}, HD, HT, D{sub 2}, DT, and T{sub 2} has been determined. For the ground state of H{sub 2} the estimated precision is 3 × 10{sup −7} cm{sup −1}, which is almost three orders of magnitude higher than that of the best previous result. The achieved accuracy removes the adiabatic contribution from the overall error budget of the present day theoretical predictions for the rovibrational levels.

  6. Accurate adiabatic correction in the hydrogen molecule

    NASA Astrophysics Data System (ADS)

    Pachucki, Krzysztof; Komasa, Jacek

    2014-12-01

    A new formalism for the accurate treatment of adiabatic effects in the hydrogen molecule is presented, in which the electronic wave function is expanded in the James-Coolidge basis functions. Systematic increase in the size of the basis set permits estimation of the accuracy. Numerical results for the adiabatic correction to the Born-Oppenheimer interaction energy reveal a relative precision of 10-12 at an arbitrary internuclear distance. Such calculations have been performed for 88 internuclear distances in the range of 0 < R ⩽ 12 bohrs to construct the adiabatic correction potential and to solve the nuclear Schrödinger equation. Finally, the adiabatic correction to the dissociation energies of all rovibrational levels in H2, HD, HT, D2, DT, and T2 has been determined. For the ground state of H2 the estimated precision is 3 × 10-7 cm-1, which is almost three orders of magnitude higher than that of the best previous result. The achieved accuracy removes the adiabatic contribution from the overall error budget of the present day theoretical predictions for the rovibrational levels.

  7. MEMS accelerometers in accurate mount positioning systems

    NASA Astrophysics Data System (ADS)

    Mészáros, László; Pál, András.; Jaskó, Attila

    2014-07-01

    In order to attain precise, accurate and stateless positioning of telescope mounts we apply microelectromechanical accelerometer systems (also known as MEMS accelerometers). In common practice, feedback from the mount position is provided by electronic, optical or magneto-mechanical systems or via real-time astrometric solution based on the acquired images. Hence, MEMS-based systems are completely independent from these mechanisms. Our goal is to investigate the advantages and challenges of applying such devices and to reach the sub-arcminute range { that is well smaller than the field-of-view of conventional imaging telescope systems. We present how this sub-arcminute accuracy can be achieved with very cheap MEMS sensors. Basically, these sensors yield raw output within an accuracy of a few degrees. We show what kind of calibration procedures could exploit spherical and cylindrical constraints between accelerometer output channels in order to achieve the previously mentioned accuracy level. We also demonstrate how can our implementation be inserted in a telescope control system. Although this attainable precision is less than both the resolution of telescope mount drive mechanics and the accuracy of astrometric solutions, the independent nature of attitude determination could significantly increase the reliability of autonomous or remotely operated astronomical observations.

  8. Accurate, reliable prototype earth horizon sensor head

    NASA Technical Reports Server (NTRS)

    Schwarz, F.; Cohen, H.

    1973-01-01

    The design and performance is described of an accurate and reliable prototype earth sensor head (ARPESH). The ARPESH employs a detection logic 'locator' concept and horizon sensor mechanization which should lead to high accuracy horizon sensing that is minimally degraded by spatial or temporal variations in sensing attitude from a satellite in orbit around the earth at altitudes in the 500 km environ 1,2. An accuracy of horizon location to within 0.7 km has been predicted, independent of meteorological conditions. This corresponds to an error of 0.015 deg-at 500 km altitude. Laboratory evaluation of the sensor indicates that this accuracy is achieved. First, the basic operating principles of ARPESH are described; next, detailed design and construction data is presented and then performance of the sensor under laboratory conditions in which the sensor is installed in a simulator that permits it to scan over a blackbody source against background representing the earth space interface for various equivalent plant temperatures.

  9. Accurate lineshape spectroscopy and the Boltzmann constant.

    PubMed

    Truong, G-W; Anstie, J D; May, E F; Stace, T M; Luiten, A N

    2015-01-01

    Spectroscopy has an illustrious history delivering serendipitous discoveries and providing a stringent testbed for new physical predictions, including applications from trace materials detection, to understanding the atmospheres of stars and planets, and even constraining cosmological models. Reaching fundamental-noise limits permits optimal extraction of spectroscopic information from an absorption measurement. Here, we demonstrate a quantum-limited spectrometer that delivers high-precision measurements of the absorption lineshape. These measurements yield a very accurate measurement of the excited-state (6P1/2) hyperfine splitting in Cs, and reveals a breakdown in the well-known Voigt spectral profile. We develop a theoretical model that accounts for this breakdown, explaining the observations to within the shot-noise limit. Our model enables us to infer the thermal velocity dispersion of the Cs vapour with an uncertainty of 35 p.p.m. within an hour. This allows us to determine a value for Boltzmann's constant with a precision of 6 p.p.m., and an uncertainty of 71 p.p.m. PMID:26465085

  10. Fast and Accurate Exhaled Breath Ammonia Measurement

    PubMed Central

    Solga, Steven F.; Mudalel, Matthew L.; Spacek, Lisa A.; Risby, Terence H.

    2014-01-01

    This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations. PMID:24962141

  11. Recent advances in surgical planning & navigation for tumor biopsy and resection.

    PubMed

    Wang, Defeng; Ma, Diya; Wong, Matthew Lun; Wáng, Yì Xiáng J

    2015-10-01

    This paper highlights recent advancements in imaging technologies for surgical planning and navigation in tumor biopsy and resection which need high-precision in detection and characterization of lesion margin in preoperative planning and intraoperative navigation. Multimodality image-guided surgery platforms brought great benefits in surgical planning and operation accuracy via registration of various data sets with information on morphology [X-ray, magnetic resonance (MR), computed tomography (CT)], function connectivity [functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), rest-status fMRI], or molecular activity [positron emission tomography (PET)]. These image-guided platforms provide a correspondence between the pre-operative surgical planning and intra-operative procedure. We envisage that the combination of advanced multimodal imaging, three-dimensional (3D) printing, and cloud computing will play increasingly important roles in planning and navigation of surgery for tumor biopsy and resection in the coming years. PMID:26682133

  12. Recent advances in surgical planning & navigation for tumor biopsy and resection

    PubMed Central

    Ma, Diya; Wong, Matthew Lun; Wáng, Yì Xiáng J.

    2015-01-01

    This paper highlights recent advancements in imaging technologies for surgical planning and navigation in tumor biopsy and resection which need high-precision in detection and characterization of lesion margin in preoperative planning and intraoperative navigation. Multimodality image-guided surgery platforms brought great benefits in surgical planning and operation accuracy via registration of various data sets with information on morphology [X-ray, magnetic resonance (MR), computed tomography (CT)], function connectivity [functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), rest-status fMRI], or molecular activity [positron emission tomography (PET)]. These image-guided platforms provide a correspondence between the pre-operative surgical planning and intra-operative procedure. We envisage that the combination of advanced multimodal imaging, three-dimensional (3D) printing, and cloud computing will play increasingly important roles in planning and navigation of surgery for tumor biopsy and resection in the coming years. PMID:26682133

  13. Chewing gum in the preoperative fasting period: an analysis of de-identified incidents reported to webAIRS.

    PubMed

    Shanmugam, S; Goulding, G; Gibbs, N M; Taraporewalla, K; Culwick, M

    2016-03-01

    The role of preoperative fasting is well established in current anaesthetic practice with different guidelines for clear fluids and food. However, chewing gum may not be categorised as either food or drink by some patients, and may not always be specified in instructions given to patients about preoperative fasting. The aim of this paper was to review anaesthesia incidents involving gum chewing reported to webAIRS to obtain information on the risks, if any, of gum chewing during the preoperative fasting period. There were nine incidents involving chewing gum reported between late 2009 and early 2015. There were no adverse outcomes from the nine incidents other than postponement of surgery in three cases and cancellation in one. In particular, there were no reports of aspiration or airway obstruction. Nevertheless, there were five cases in which the gum was not detected preoperatively and was found in the patient's mouth either intraoperatively or postoperatively. These cases of undetected gum occurred despite patient and staff compliance with their current preoperative checklists. While the risk of increased gastric secretions related to chewing gum preoperatively are not known, the potential for airway obstruction if the gum is not detected and removed preoperatively is very real. We recommend that patients should be specifically advised to avoid gum chewing once fasting from clear fluids is commenced, and that a specific question regarding the presence of chewing gum should be added to all preoperative checklists. PMID:27029662

  14. Preoperative Preparation for Cardiac Surgery Facilitates Recovery, Reduces Psychological Distress, and Reduces the Incidence of Acute Postoperative Hypertension.

    ERIC Educational Resources Information Center

    Anderson, Erling A.

    1987-01-01

    Cardiac surgery patients were assigned to information-only, information-plus-coping, or control preoperative preparation groups. Preoperatively, both experimental groups were significantly less anxious than were controls. Both experimental groups increased patients' belief in control over recovery. Postoperatively, experimental patients were less…

  15. 3D soft tissue predictions with a tetrahedral mass tensor model for a maxillofacial planning system: a quantitative validation study

    NASA Astrophysics Data System (ADS)

    Mollemans, W.; Schutyser, F.; Nadjmi, N.; Maes, F.; Suetens, P.

    2006-03-01

    In this paper we present an extensive quantitative validation on 3D facial soft tissue simulation for maxillofacial surgery planning. The study group contained 10 patients. In previous work we presented a new Mass Tensor Model to simulate the new facial appearance after maxillofacial surgery in a fast way. 10 patients were preoperatively CT-scanned and the surgical intervention was planned. 4 months after surgery, a post-operative control CT was acquired. In this study, the simulated facial outlook is compared with post-operative image data. After defining corresponding points between the predicted and actual post-operative facial skin surface, using a variant of the non-rigid TPS-RPM algorithm, distances between these correspondences are quantified and visualized in 3D. As shown, the average median distance measures only 0.60 mm and the average 90% percentile stays below 1.5 mm. We can conclude that our model clearly provides an accurate prediction of the real post-operative outcome and is therefore suitable for use in clinical practice.

  16. Quantitative modeling of the accuracy in registering preoperative patient-specific anatomic models into left atrial cardiac ablation procedures

    SciTech Connect

    Rettmann, Maryam E. Holmes, David R.; Camp, Jon J.; Cameron, Bruce M.; Robb, Richard A.; Kwartowitz, David M.; Gunawan, Mia; Johnson, Susan B.; Packer, Douglas L.; Dalegrave, Charles; Kolasa, Mark W.

    2014-02-15

    Purpose: In cardiac ablation therapy, accurate anatomic guidance is necessary to create effective tissue lesions for elimination of left atrial fibrillation. While fluoroscopy, ultrasound, and electroanatomic maps are important guidance tools, they lack information regarding detailed patient anatomy which can be obtained from high resolution imaging techniques. For this reason, there has been significant effort in incorporating detailed, patient-specific models generated from preoperative imaging datasets into the procedure. Both clinical and animal studies have investigated registration and targeting accuracy when using preoperative models; however, the effect of various error sources on registration accuracy has not been quantitatively evaluated. Methods: Data from phantom, canine, and patient studies are used to model and evaluate registration accuracy. In the phantom studies, data are collected using a magnetically tracked catheter on a static phantom model. Monte Carlo simulation studies were run to evaluate both baseline errors as well as the effect of different sources of error that would be present in a dynamicin vivo setting. Error is simulated by varying the variance parameters on the landmark fiducial, physical target, and surface point locations in the phantom simulation studies. In vivo validation studies were undertaken in six canines in which metal clips were placed in the left atrium to serve as ground truth points. A small clinical evaluation was completed in three patients. Landmark-based and combined landmark and surface-based registration algorithms were evaluated in all studies. In the phantom and canine studies, both target registration error and point-to-surface error are used to assess accuracy. In the patient studies, no ground truth is available and registration accuracy is quantified using point-to-surface error only. Results: The phantom simulation studies demonstrated that combined landmark and surface-based registration improved

  17. Case Relationships in the Creative Oral Language of Preoperational and Concrete Operational First Graders.

    ERIC Educational Resources Information Center

    McCabe, Patrick P.

    The creative oral language elicited from 45 preoperational and 40 concrete operational first grade students was analyzed to study the relationship between cognitive development and the types of case relationships produced. Each child's language was analyzed for eight noun/verb relationships, including state, process, action, experience, location,…

  18. Short-term preoperative octreotide treatment for TSH-secreting pituitary adenoma.

    PubMed

    Fukuhara, Noriaki; Horiguchi, Kentaro; Nishioka, Hiroshi; Suzuki, Hisanori; Takeshita, Akira; Takeuchi, Yasuhiro; Inoshita, Naoko; Yamada, Shozo

    2015-01-01

    Preoperative control of hyperthyroidism in patients with TSH-secreting pituitary adenomas (TSHoma) may avoid perioperative thyroid storm. Perioperative administration of octreotide may control hyperthyroidism, as well as shrink tumor size. The effects of preoperative octreotide treatment were assessed in a large number of patients with TSHomas. Of 81 patients who underwent surgery for TSHoma at Toranomon Hospital between January 2001 and May 2013, 44 received preoperative short-term octreotide. After excluding one patient because of side effects, 19 received octreotide as a subcutaneous injection, and 24 as a long-acting release (LAR) injection. Median duration between initiation of octreotide treatment and surgery was 33.5 days. Octreotide normalized free T4 in 36 of 43 patients (84%) and shrank tumors in 23 of 38 (61%). Length of octreotide treatment did not differ significantly in patients with and without hormonal normalization (p=0.09) and with and without tumor shrinkage (p=0.84). Serum TSH and free T4 concentrations, duration of treatment, incidence of growth hormone (GH) co-secretion, results of octreotide loading tests, form of administration (subcutaneous injection or LAR), tumor volume, and tumor consistency did not differ significantly in patients with and without hormonal normalization and with and without tumor shrinkage. Short-term preoperative octreotide administration was highly effective for TSHoma shrinkage and normalization of excess hormone concentrations, with tolerable side effects. PMID:25273395

  19. Preoperative fasting times in elective surgical patients at a referral Hospital in Botswana

    PubMed Central

    Abebe, Worknehe Agegnehu; Rukewe, Ambrose; Bekele, Negussie Alula; Stoffel, Moeng; Dichabeng, Mompelegi Nicoh; Shifa, Jemal Zeberga

    2016-01-01

    Introduction Adults and children are required to fast before anaesthesia to reduce the risk of regurgitation and aspiration of gastric contents. However, prolonged periods of fasting are unnecessary and may cause complications. This study was conducted to evaluate preoperative fasting period in our centre and compare it with the ASA recommendations and factors that influence fasting periods. Methods This is a cross-sectional study of preoperative fasting times among elective surgical patients. A total numbers of 260 patients were interviewed as they arrived at the reception area of operating theatre using questionnaire. Results Majority of patients (98.1%) were instructed to fast from midnight. Fifteen patients (5.8%) reported that they were told the importance of preoperative fasting. The mean fasting period were 15.9±2.5 h (range 12.0-25.3 h) for solids and 15.3±2.3 h (range 12.0-22.0 h) for liquids. The mean duration of fasting was significantly longer for patients operated after midday compared to those operated before midday, p<0.001. Conclusion The mean fasting periods were 7.65 times longer for clear liquid and 2.5 times for solids than the ASA guidelines. It is imperative that the Hospital should establish Preoperative fasting policies and teach the staff who should ensure compliance with guidelines. PMID:27222691

  20. VALUE OF PREOPERATIVE RADIOGRAPHIC EVALUATIONS ON KNEE BONE DEFECTS FOR REVISION ARTHROPLASTY

    PubMed Central

    Iamaguchi, Mauricio Masasi; Helito, Camilo Partezani; Gobbi, Riccardo Gomes; Demange, Marco Kawamura; Tirico, Luiz Eduardo Passarelli; Pecora, Jose Ricardo; Camanho, Gilberto Luis

    2015-01-01

    Objective: To evaluate the value of preoperative radiographic evaluations for total knee arthroplasty (TKA) revision. Methods: Thirty-one knees that were operated between 2006 and 2008, in a consecutive series of cases of TKA revision surgery were analyzed retrospectively. The following criteria were evaluated: number of wedges or structured bone grafts used for filling the bone defects; locations of the wedges and bone grafts used; and mean thickness of the polyethylene used. The AORI classification was previously established based on preoperative radiographs, using preestablished criteria. After the analysis, the knees were divided into four groups (I, IIA, IIB and III). Results: The mean number of wedges or grafts used in each knee progressively increased among the groups (group I: 1.33; group IIA: 2; group IIB: 4.33; and group III: 4.83) (P = 0.0012). The commonest locations were medial in the tibia and posteromedial in the femur. There were no statistically significant differences in the thickness of the polyethylene used. Conclusion: The AORI classification for bone defects in the knee, based on preoperative radiographs, showed a correlation with increasing need to use wedges and/or structured grafts in TKA revisions. However, up to 46% of the knees in groups I and IIA presented bone defects of up to 5 mm that were not diagnosed by means of preoperative radiographs. PMID:27047889