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Sample records for post-stenting intravascular brachytherapy

  1. Post-stenting Intravascular Brachytherapy Trials on Hypercholesterolemic Rabbits Using 32P Liquid Sources: Implications for Prevention of In-Stent Restenosis

    SciTech Connect

    Wilczek, Krzysztof; Walichiewicz, Piotr; Petelenz, Barbara; Jachec, Wojciech; Jochem, Jerzy; Tomasik, Andrzej; Bilski, Pawel; Snietura, Miroslaw; Wodniecki, Jan

    2002-08-15

    Purpose: Liquid sources of radiation delivered in angioplasty balloons may be a convenient self-centering device used for prevention of in-stent restenosis. To test the effectiveness of this method an intravascular brachytherapy study was performed using 32P liquid sources in an animal model. Methods: The radial dose distribution around angioplasty balloons filled with solutions of Na2H32PO4 was calibrated by thermoluminescence dosimetry. The animal experiments were performed in rabbits with induced hypercholesterolemia. The balloons containing 32P were introduced into iliac arteries immediately after stent implantation. Estimated 7-49 Gy doses required 30-100 minirradiations. Radiation effects were evaluated by comparing the thickness of various components of the artery wall. Results:Doses of 7, 12, 16 or 49 Gy on the internal artery surface required 30-100 min of irradiation. The dose of 49 Gy at 'zero' distance corresponding to 16 Gy at 1.0 mm from the balloon surface reduced hypertrophy in every layer of the arterial wall: in the intima the cross-sectional areas were 0.13 versus 0.91 mm2, in the media were 0.5 versus 0.46 mm2 and in the adventitia were 0.04 versus 0.3 mm2 (p <0.05). A dose of 7 Gyat the balloon surface produced adverse irradiation effects: the intimal area of the artery was 2.087 versus 0.857 mm2, the medial area was 0.59 versus 0.282 mm2 and the adventitial area was 0.033 versus 0.209 mm2 in treated and control arteries, respectively.Conclusion: Application of a 49 Gy irradiation dose to the internal arterial surface effectively prevented in-stentrestenosis.

  2. Improved dosimetry techniques for intravascular brachytherapy

    NASA Astrophysics Data System (ADS)

    Sehgal, Varun

    Coronary artery disease leads to the accumulation of atheromatous plaque leading to coronary stenosis. Coronary intervention techniques such as balloon angioplasty and atherectomy are used to address coronary stenosis and establish a stable lumen thus enhancing blood flow to the myocardium. Restenosis or re-blockage of the arteries is a major limitation of the above mentioned interventional techniques. Neointimal hyperplasia or proliferation of cells in response to the vascular injury as a result of coronary intervention is considered to be one of the major causes of restenosis. Recent studies indicated that irradiation of the coronary lesion site, with radiation doses ranging from 15 to 30 Gy, leads to diminishing neointimal hyperplasia with subsequent reduction in restenosis. The radiation dose is given by catheter-based radiation delivery systems using beta-emitters 90Sr/90Y, 32P and gamma-emitting 192Ir among others. However the dose schema used for dose prescription for these sources are relatively simplistic, and are based on calculations using uniform homogenous water or tissue media and simple cylinder geometry. Stenotic coronary vessels are invariably lined with atheromatous plaque of heterogeneous composition, the radiation dose distribution obtained from such dosimetry data can cause significant variations in the actual dose received by a given patient. Such discrepancies in dose calculation can introduce relatively large uncertainties in the limits of dose window for effective and safe application of intravascular brachytherapy, and consequently in the clinical evaluation of the efficacy of this modality. In this research study we investigated the effect of different geometrical and material heterogeneities, including residual plaque, catheter non-centering, lesion eccentricity and cardiac motion on the radiation dose delivered at the lesion site. Correction factors including dose perturbation factors and dose variation factors have been calculated

  3. Optimization of intravascular brachytherapy treatment planning in peripheral arteries.

    PubMed

    Zhou, Zhengdong; Haigron, Pascal; Shu, Huazhong; Yu, Wenxue; Moisan, Cécile; Manens, Jean-Pierre; Lucas, Antoine; Luo, Limin

    2007-09-01

    This work deals with the treatment planning optimization for intravascular brachytherapy (IVB) in peripheral arteries. The objective is both to quantitatively study the validity of different hypotheses required for a reliable application of the treatment with current techniques, and to contribute to the definition and the specification of a new optimized procedure taking into account the actual patient's vessel geometry. The detection of vascular luminal surface was performed by an image analysis process, i.e., virtual active navigation, applied to standard CT data. Dose distribution was calculated according to the formalism proposed and recommended by the AAPM in TG43 and TG60. A method combining simulated annealing and BFGS algorithms was applied to optimize the parameters associated with the dwell points such as their number, positions, and dwell times. Dose-surface histogram (DSH) was used to evaluate the dose distribution results. Four levels of accuracy in target surface description were tested. The application of this optimization method to four different CT data sets including patient data, phantom and animal models showed that the treatment plan can be improved when the actual vessel geometry has been taken into account.

  4. Gadolinium neutron capture brachytherapy (GdNCB), a new treatment method for intravascular brachytherapy

    SciTech Connect

    Enger, Shirin A.; Rezaei, Arash; Munck af Rosenschoeld, Per; Lundqvist, Hans

    2006-01-15

    Restenosis is a major problem after balloon angioplasty and stent implantation. The aim of this study is to introduce gadolinium neutron capture brachytherapy (GdNCB) as a suitable modality for treatment of stenosis. The utility of GdNCB in intravascular brachytherapy (IVBT) of stent stenosis is investigated by using the GEANT4 and MCNP4B Monte Carlo radiation transport codes. To study capture rate, Kerma, absorbed dose and absorbed dose rate around a Gd-containing stent activated with neutrons, a 30 mm long, 5 mm diameter gadolinium foil is chosen. The input data is a neutron spectrum used for clinical neutron capture therapy in Studsvik, Sweden. Thermal neutron capture in gadolinium yields a spectrum of high-energy gamma photons, which due to the build-up effect gives an almost flat dose delivery pattern to the first 4 mm around the stent. The absorbed dose rate is 1.33 Gy/min, 0.25 mm from the stent surface while the dose to normal tissue is in order of 0.22 Gy/min, i.e., a factor of 6 lower. To spare normal tissue further fractionation of the dose is also possible. The capture rate is relatively high at both ends of the foil. The dose distribution from gamma and charge particle radiation at the edges and inside the stent contributes to a nonuniform dose distribution. This will lead to higher doses to the surrounding tissue and may prevent stent edge and in-stent restenosis. The position of the stent can be verified and corrected by the treatment plan prior to activation. Activation of the stent by an external neutron field can be performed days after catherization when the target cells start to proliferate and can be expected to be more radiation sensitive. Another advantage of the nonradioactive gadolinium stent is the possibility to avoid radiation hazard to personnel.

  5. Estimating the actual dose delivered by intravascular coronary brachytherapy using geometrically correct 3D modeling

    NASA Astrophysics Data System (ADS)

    Wahle, Andreas; Lopez, John J.; Pennington, Edward C.; Meeks, Sanford L.; Braddy, Kathleen C.; Fox, James M.; Brennan, Theresa M. H.; Buatti, John M.; Rossen, James D.; Sonka, Milan

    2003-05-01

    Intravascular brachytherapy has shown to reduce re-occurrence of in-stent restenosis in coronary arteries. For beta radiation, application time is determined from source activity and the angiographically estimated vessel diameter. Conventionally used dosing models assume a straight vessel with the catheter centered and a constant-diameter circular cross section. Aim of this study was to compare the actual dose delivered during in-vivo intravascular brachytherapy with the target range determined from the patient's prescribed dose. Furthermore, differences in dose distribution between a simplified tubular model (STM) and a geometrically correct 3-D model (GCM) obtained from fusion between biplane angiography and intravascular ultrasound were quantified. The tissue enclosed by the segmented lumen/plaque and media/adventitia borders was simulated using a structured finite-element mesh. The beta-radiation sources were modeled as 3-D objects in their angiographically determined locations. The accumulated dose was estimated using a fixed distance function based on the patient-specific radiation parameters. For visualization, the data was converted to VRML with the accumulated doses represented by color encoding. The statistical comparison between STM and GCM models in 8 patients showed that the STM significantly underestimates the dose delivered and its variability. The analysis revealed substantial deviations from the target dose range in curved vessels.

  6. Monte Carol-Based Dosimetry of Beta-Emitters for Intravascular Brachytherapy

    SciTech Connect

    Choi, C.K.

    2002-06-25

    Monte Carlo simulations for radiation dosimetry and the experimental verifications of the simulations have been developed for the treatment geometry of intravascular brachytherapy, a form of radionuclide therapy for occluded coronary disease (restenosis). Monte Carlo code, MCNP4C, has been used to calculate the radiation dose from the encapsulated array of B-emitting seeds (Sr/Y-source train). Solid water phantoms have been fabricated to measure the dose on the radiochromic films that were exposed to the beta source train for both linear and curved coronary vessel geometries. While the dose difference for the 5-degree curved vessel at the prescription point of f+2.0 mm is within the 10% guideline set by the AAPM, however, the difference increased dramatically to 16.85% for the 10-degree case which requires additional adjustment for the acceptable dosimetry planning. The experimental dose measurements agree well with the simulation results

  7. Use of water-equivalent plastic scintillator for intravascular brachytherapy dosimetry.

    PubMed

    Geso, M; Robinson, N; Schumer, W; Williams, K

    2004-03-01

    Beta irradiation has recently been investigated as a possible technique for the prevention of restenosis in intravascular brachytherapy after balloon dilatation or stent implantation. Present methods of beta radiation dosimetry are primarily conducted using radiochromic film. These film dosimeters exhibit limited sensitivity and their characteristics differ from those of tissue, therefore the dose measurement readings require correction factors to be applied. In this work a novel, mini-size (2 mm diameter by 5 mm long) dosimeter element fabricated from Organic Plastic Scintillator (OPS) material was employed. Scintillation photon detection is accomplished using a precision photodiode and innovative signal amplification and processing techniques, rather than traditional photomultiplier tube methods. A significant improvement in signal to noise ratio, dynamic range and stability is achieved using this set-up. In addition, use of the non-saturating organic plastic scintillator material as the detector enables the dosimeter to measure beta radiation at very close distances to the source. In this work the plastic scintillators have been used to measure beta radiation dose at distances of less than 1 mm from an Sr-90 cardiovascular brachytherapy source having an activity of about 2.1 GBq beta radiation levels for both depth-distance and longitudinal profile of the source pellet chain, both in air and in liquid water, are measured using this system. The data obtained is compared with results from Monte Carlo simulation technique (MCNP 4B). Plastic scintillator dosimeter elements, when used in conjunction with photodiode detectors may prove to be useful dosimeters for cardiovascular brachytherapy beta sources, or other applications where precise near-source field dosimetry is required. The system described is particularly useful where measurement of actual dose rate in real time, a high level of stability and repeatability, portability, and immediate access to results are

  8. Effectiveness Evaluation of Skin Covers against Intravascular Brachytherapy Sources Using VARSKIN3 Code

    PubMed Central

    Baghani, H R; Nazempour, A R; Aghamiri, S M R; Hosseini Daghigh, S M; Mowlavi, A A

    2013-01-01

    Background and Objective: The most common intravascular brachytherapy sources include 32P, 188Re, 106Rh and 90Sr/90Y. In this research, skin absorbed dose for different covering materials in dealing with these sources were evaluated and the best covering material for skin protection and reduction of absorbed dose by radiation staff was recognized and recommended. Method: Four materials including polyethylene, cotton and two different kinds of plastic were proposed as skin covers and skin absorbed dose at different depths for each kind of the materials was calculated separately using the VARSKIN3 code. Results: The results suggested that for all sources, skin absorbed dose was minimized when using polyethylene. Considering this material as skin cover, maximum and minimum doses at skin surface were related to 90Sr/90Y and 106Rh, respectively. Conclusion: polyethylene was found the most effective cover in reducing skin dose and protecting the skin. Furthermore, proper agreement between the results of VARSKIN3 and other experimental measurements indicated that VRASKIN3 is a powerful tool for skin dose calculations when working with beta emitter sources. Therefore, it can be utilized in dealing with the issue of radiation protection. PMID:25505758

  9. The Monte Carlo-Based Dosimetry of Beta Emitters for Intravascular Brachytherapy

    SciTech Connect

    Choi, C.K.; Son, J.; Ye, S.J.

    2001-06-17

    Intravascular brachytherapy (IVBT) is a new radiotherapy modality to prevent restenosis (re-blockage of the coronary artery) following interventional coronary angioplasty. It is estimated that the restenosis rate may drop from {approx}35 to 40% to well below 10% if radiation is delivered to the obstruction site during or after angioplasty. In traditional brachytherapy, the dose is typically specified at 1 cm from the source, and the effects of low-energy photons and secondary electrons are essentially ignored. In IVBT, however, the entire lesion may be 1 to 3 mm in thickness. A better understanding of dosimetry in the millimetre range will help in the development of optimum clinical devices and their efficacious use in different institutions using different radionuclides and devices. The actual treatment geometry consists of an encapsulated train of seeds, a guide wire, and a stent in a curved vessel. The source is a cylindrical train of 12 source seeds, each having dimensions of 0.64 mm in diameter and 2.5 mm in length, and proximal/distal gold markers. Each seed contains {sup 90}Sr/Y mixed with fired ceramic encapsulated in a 0.04-mm stainless steel wall. The Monte Carlo simulations are carried out for the trained source geometries in the linear and curved vessels with and without a stent. The stent structure is approximately modeled as a set of tori with a rotational radius of 1.92 mm from the source axis and a circular radius of 0.08 mm in cross section. Five tori are equally spaced for each seed. The stent shadows 31% of the total area of the source surface. The total activity of 70 mCi (2.59 x 10{sup 9} Bq) was chosen from manufacturer data. The corresponding mass fraction of {sup 90}Sr/Y in the source ceramic is negligible and was not explicitly included in the MCNP simulations. All tallies were multiplied with 5.83 mCi/seed x 3.7 x 10{sup 7} s/mCi for one active seed, and then the tallies that made contributions to the dose in a voxel of interest were

  10. Preparation and preliminary biological evaluation of a (166)Ho labeled polyazamacrocycle for possible use as an intravascular brachytherapy (IVBT) agent.

    PubMed

    Chakraborty, Sudipta; Das, Tapas; Banerjee, Sharmila; Sarma, H D; Venkatesh, Meera

    2006-04-01

    (166)Ho can be considered as a potential radionuclide for intravascular brachytherapy (IVBT) using liquid-filled balloons owing to its suitable nuclear decay characteristics. The possibility of producing (166)Ho with adequate specific activity using moderate flux reactors and natural holmium target makes it an attractive alternative of (188)Re for developing IVBT agents. Keeping in mind the high thermodynamic stability of lanthanide complexes with polyazamacrocycles, (166)Ho complex of 1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetraacetic acid (TETA) was prepared and studied for its suitability as a possible agent for IVBT. (166)Ho was produced with adequate specific activity and high radionuclidic purity by irradiating natural Ho(2)O(3) powder. TETA was synthesized by a single step procedure using cyclam as the starting material. (166)Ho-TETA complex was prepared with excellent radiochemical purity and the complex was found to retain its stability for 7 days at room temperature. Biodistribution studies carried out in Wistar rats showed major renal clearance of the injected activity with almost no retention in any of the vital organ/tissue.

  11. Evaluation of EGS4/PRESTA multiple-scattering algorithms for 90Sr/90Y intravascular brachytherapy dosimetry.

    PubMed

    Wang, R; Li, X A; Yu, C X

    2000-08-01

    The purpose of this work is to evaluate the EGS4/PRESTA electron multiple-scattering (MS) algorithms for dose calculation in intravascular brachytherapy (IVBT) using a 90Sr/90Y source. The small source size and the small volume of interest in IVBT require very fine spatial resolution, which may break down the constraints of Molière's MS theory as implemented in EGS4. The theory is accurate only when the electron step sizes are large enough to allow the number of collisions omega0 to be much greater than e = 2.7183. When step sizes are too small to allow at least 2.7183 collisions, as may be necessitated by the fine geometry, the algorithm may switch off MS, producing dosimetric artefacts. This study showed that switching off MS could produce a dose deviation of up to 6% when the half-thickness (d/2) of the dose scoring region is comparable with the Moliere minimum step size (t(min) = 2.7183). The effect of switching off MS is negligible if d/2 > t(min) For the case of omega0 > e, if the electron step sizes are chosen to allow five to 40 collisions, with increasing step size, the doses surrounding the source increase and the error decreases. On the other hand, when larger step sizes are chosen, the dose calculation voxel size must also be increased in order for the calculations to converge. A good compromise between accuracy and applicability for IVBT simulation can be made, if the thickness of the scoring region is 0.1 mm and the electron step sizes are in the range allowing 10 to 30 collisions.

  12. Brachytherapy

    MedlinePlus

    ... smaller area in less time than conventional external beam radiation therapy. Brachytherapy is used to treat cancers ... to kill cancer cells and shrink tumors. External beam radiation therapy (EBRT) involves high-energy x-ray ...

  13. Dose perturbation of a novel cobalt chromium coronary stent on {sup 32}P intravascular brachytherapy: A Monte Carlo study

    SciTech Connect

    Mourtada, Firas; Horton, John L.

    2005-01-01

    Intravascular brachytherapy has been adopted for the indication of in-stent restenosis on the basis of results of clinical trials using mainly stainless steel stents. Recently, a new stent made of cobalt-chromium L-605 alloy (CoCr, {rho}=9.22 g/cm{sup 3}) (MULTI-LINK VISION{sup TM}) was introduced as an alternative to the 316L stainless steel stent design (SS, {rho}=7.87 g/cm{sup 3}) (MULTI-LINK PENTA{sup TM}). In this work, we used the Monte Carlo code MCNPX to compare the dose distribution for the {sup 32}P GALILEO{sup TM} source in CoCr and SS 8 mm stent models. The dose perturbation factor (DPF), defined as the ratio of the dose in water with the presence of a stent to the dose without a stent, was used to compare results. Both stent designs were virtually expanded to diameters of 2.0, 3.0, and 4.0 mm using finite element models. The complicated strut shapes of both the CoCr and SS stents were simplified using circular rings with an effective width to yield a metal-to-tissue ratio identical to that of the actual stents. The mean DPF at a 1 mm tissue depth, over the entire stented length of 8 mm, was 0.935 for the CoCr stent and 0.911 for the SS stent. The mean DPF at the intima (0.05 mm radial distance from the strut outer surface), over the entire stented length of 8 mm, was 0.950 for CoCr, and 0.926 for SS. The maximum DPFs directly behind the CoCr and SS struts were 0.689 and 0.644, respectively. All DPF estimates have a standard deviation of {+-}0.6%(k=2), approximating the 95% confidence interval. Although the CoCr stent has a higher effective atomic number and greater density than the SS stent, the DPFs for the two stents are similar, probably because the metal-to-tissue ratio and strut thickness of the CoCr stent are lower than those of the SS stent.

  14. Post-Dilatation Intravascular Brachytherapy Trials on Hypercholesterolemic Rabbits Using {sup 32}P-Phosphate Solutions in Angioplasty Balloons

    SciTech Connect

    Walichiewicz, Piotr Wilczek, Krzysztof; Petelenz, Barbara; Jachec, Wojciech; Jochem, Jerzy; Tomasik, Andrzej; Bilski, Pawel; Gaca, Pawel; Banaszczuk, Joanna; Ihnatowicz, Jerzy; Wodniecki, Jan

    2004-01-15

    Response of peripheral arteries to post-dilatation intravascular brachytherapy (IVBT) using {sup 32}P liquid sources was studied in a rabbit model. The applied sources were angioplasty balloons filled with aqueous solutions of Na{sub 2}H{sup 32}PO{sub 4}, NaCl and iodinated contrast. Dose distribution was calibrated by thermoluminescence dosimetry. The uncertainty of in vitro determinations of the activity-dose dependence was {+-} 15-30%. The animal experiments were performed on rabbits with induced hypercholesterolemia. The {sup 32}P sources were introduced into a randomly chosen (left or right) iliac artery, immediately after balloon injury. Due to the low specific activity of the applied sources, the estimated 7-49 Gy doses on the internal artery surface required 30-100 min irradiations. A symmetric, balloon-occluded but non-irradiated artery of the same animal served as control. Radiation effects were evaluated by comparing the thicknesses of various components of irradiated versus untreated artery walls of each animal. The treatment was well tolerated by the animals. The effects of various dose ranges could be distinguished although differences in individual biological reactions were large. Only the 49 Gy dose at 'zero' distance (16 Gy at 1.0 mm from the balloon surface) reduced hypertrophy in every active layer of the artery wall. The cross-sectional intimal thicknesses after 7, 12, 38 and 49 Gy doses were 0.277, 0.219, 0.357 and 0.196 mm{sup 2} respectively, versus 0.114, 0.155, 0.421 and 0.256 mm{sup 2} in controls (p < 0.05). The lowest radiation dose on the intima induced the opposite effect. Edge intimal hyperplasia was not avoided, which agrees with other reports. The edge restenosis and the variability of individual response to identical treatment conditions must be considered as limitations of the post-dilatation IVBT method. Only application of highest irradiation doses was effective. The irradiation dose should be planned and calculated for

  15. Dose calculation formalisms and consensus dosimetry parameters for intravascular brachytherapy dosimetry: Recommendations of the AAPM Therapy Physics Committee Task Group No. 149

    SciTech Connect

    Chiu-Tsao, Sou-Tung; Schaart, Dennis R.; Soares, Christopher G.; Nath, Ravinder

    2007-11-15

    Since the publication of AAPM Task Group 60 report in 1999, a considerable amount of dosimetry data for the three coronary brachytherapy systems in use in the United States has been reported. A subgroup, Task Group 149, of the AAPM working group on Special Brachytherapy Modalities (Bruce Thomadsen, Chair) was charged to develop recommendations for dose calculation formalisms and the related consensus dosimetry parameters. The recommendations of this group are presented here. For the Cordis {sup 192}Ir and Novoste {sup 90}Sr/{sup 90}Y systems, the original TG-43 formalism in spherical coordinates should be used along with the consensus values of the dose rate constant, geometry function, radial dose function, and anisotropy function for the single seeds. Contributions from the single seeds should be added linearly for the calculation of dose distributions from a source train. For the Guidant {sup 32}P wire system, the modified TG-43 formalism in cylindrical coordinates along with the recommended data for the 20 and 27 mm wires should be used. Data tables for the 6, 10, 14, 18, and 22 seed trains of the Cordis system, 30, 40, and 60 mm seed trains of the Novoste system, and the 20 and 27 mm wires of the Guidant system are presented along with our rationale and methodology for selecting the consensus data. Briefly, all available datasets were compared with each other and the consensus dataset was either an average of available data or the one obtained from the most densely populated study; in most cases this was a Monte Carlo calculation.

  16. Intravascular ultrasound

    MedlinePlus

    IVUS; Ultrasound - coronary artery; Endovascular ultrasound; Intravascular echocardiography ... A tiny ultrasound wand is attached to the top of a thin tube. This tube is called a catheter. The catheter ...

  17. Intravascular OCT

    NASA Astrophysics Data System (ADS)

    Schmitt, Joseph M.; Adler, Desmond; Xu, Chenyang

    Since the first coronary angioplasty was performed in the late 1970s, imaging has played a central role in percutaneous coronary intervention (PCI). Today more than three million PCI procedures are performed worldwide to expand narrowed arteries and to clear blood clots that can cause debilitating symptoms of myocardial ischemia or fatal heart attacks. Although X-ray angiography is still the workhorse imaging modality in the field of interventional cardiology, intravascular imaging has become an indispensable tool for guiding complex PCI procedures. Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) are the two most commonly used catheter-based imaging technologies in coronary procedures. Since the first commercial intravascular OCT systems were introduced in Japan and the European Union in 2004 and in the United States in 2009, the application of intravascular OCT has grown rapidly [3, 15, 16].

  18. Intravascular Ultrasound for Intracranial and Extracranial Carotid Artery Stent Placement

    PubMed Central

    Hussain, Ahmad S

    2016-01-01

    Intravascular ultrasound (IVUS) can provide valuable information regarding endoluminal morphology. We present the first description of IVUS-guided intracranial and extracranial carotid artery stent placement for arterial dissection. A 41-year-old female with a sudden-onset headache and blurred vision underwent a computed tomography (CT) angiogram imaging that revealed bilateral carotid artery dissections (BCAD) and a left vertebral artery dissection (VAD). Endovascular treatment (EVT) of a long segment right carotid artery dissection (CAD) was performed employing two Carotid WALLSTENT™ Monorails™ (8 x 36 mm, 10 x 31 mm) (Boston Scientific, Marlborough, MA). With the help of the IVUS, the distal stent was placed up to the petrous carotid artery, followed by the placement of the second stent in the immediate proximal location with some overlap that extended down to the carotid artery bulb. Intraoperative angiography and post-stenting IVUS revealed excellent stent placement with good resolution of the dissection and good luminal patency with pseudolumen obliteration. Stent use for intracranial circulation dissections will continue to be a favorable option given the decreased morbidity of endovascular therapy in this location. As endovascular surgeons become more facile with the use of IVUS, using it as a guide for stent placement and post-stenting confirmation will help them to ensure proper positioning and improved patency rates. PMID:27672529

  19. Intravascular Ultrasound for Intracranial and Extracranial Carotid Artery Stent Placement

    PubMed Central

    Hussain, Ahmad S

    2016-01-01

    Intravascular ultrasound (IVUS) can provide valuable information regarding endoluminal morphology. We present the first description of IVUS-guided intracranial and extracranial carotid artery stent placement for arterial dissection. A 41-year-old female with a sudden-onset headache and blurred vision underwent a computed tomography (CT) angiogram imaging that revealed bilateral carotid artery dissections (BCAD) and a left vertebral artery dissection (VAD). Endovascular treatment (EVT) of a long segment right carotid artery dissection (CAD) was performed employing two Carotid WALLSTENT™ Monorails™ (8 x 36 mm, 10 x 31 mm) (Boston Scientific, Marlborough, MA). With the help of the IVUS, the distal stent was placed up to the petrous carotid artery, followed by the placement of the second stent in the immediate proximal location with some overlap that extended down to the carotid artery bulb. Intraoperative angiography and post-stenting IVUS revealed excellent stent placement with good resolution of the dissection and good luminal patency with pseudolumen obliteration. Stent use for intracranial circulation dissections will continue to be a favorable option given the decreased morbidity of endovascular therapy in this location. As endovascular surgeons become more facile with the use of IVUS, using it as a guide for stent placement and post-stenting confirmation will help them to ensure proper positioning and improved patency rates.

  20. Intravascular Ultrasound for Intracranial and Extracranial Carotid Artery Stent Placement.

    PubMed

    Hussain, Ahmad S; Hussain, Namath S

    2016-01-01

    Intravascular ultrasound (IVUS) can provide valuable information regarding endoluminal morphology. We present the first description of IVUS-guided intracranial and extracranial carotid artery stent placement for arterial dissection. A 41-year-old female with a sudden-onset headache and blurred vision underwent a computed tomography (CT) angiogram imaging that revealed bilateral carotid artery dissections (BCAD) and a left vertebral artery dissection (VAD). Endovascular treatment (EVT) of a long segment right carotid artery dissection (CAD) was performed employing two Carotid WALLSTENT™ Monorails™ (8 x 36 mm, 10 x 31 mm) (Boston Scientific, Marlborough, MA). With the help of the IVUS, the distal stent was placed up to the petrous carotid artery, followed by the placement of the second stent in the immediate proximal location with some overlap that extended down to the carotid artery bulb. Intraoperative angiography and post-stenting IVUS revealed excellent stent placement with good resolution of the dissection and good luminal patency with pseudolumen obliteration. Stent use for intracranial circulation dissections will continue to be a favorable option given the decreased morbidity of endovascular therapy in this location. As endovascular surgeons become more facile with the use of IVUS, using it as a guide for stent placement and post-stenting confirmation will help them to ensure proper positioning and improved patency rates. PMID:27672529

  1. Intravascular ultrasound characterization of the "black hole" phenomenon after drug-eluting stent implantation.

    PubMed

    Costa, Marco A; Sabate, Manel; Angiolillo, Dominick J; Jimenez-Quevedo, Pilar; Teirstein, Paul; Carter, Andrew; Leon, Martin B; Moses, Jeffrey; Zenni, Martin; Yakubov, Steven; Guzman, Luis A; Gilmore, Paul; Macaya, Carlos; Bass, Theodore A

    2006-01-15

    An intraluminal echolucent tissue, dubbed "black hole," has been identified by intravascular ultrasonography after intracoronary brachytherapy. This study reports the characteristics and incidence of the black hole in patients treated with drug-eluting stent implantation using a sirolimus-eluting stent (SES). We included intravascular ultrasound data from the Compassionate Use of Sirolimus-Eluting Stent (SECURE, n = 61 lesions) registry, a study involving patients in whom previous brachytherapy had failed, and the DIABETES trial (n = 165 lesions), a multicenter, randomized study comparing SES versus bare metal stents in diabetic patients. Intravascular ultrasound follow-up was scheduled at 8 months (SECURE trial, post-brachytherapy population) and 9 months (DIABETES trial). In the SECURE population, a black hole was observed in 10 patients (19.6%). Seven black hole segments had significant intimal hyperplasia (> 10%). A black hole accounted for 27% of total intraluminal tissue. In the DIABETES trial, 2 patients (2.5%) in the SES group and none in the bare metal stent group showed echolucent intimal hyperplasia. In conclusion, a black hole occurred frequently after implantation of a SES in patients in whom intracoronary brachytherapy had previously failed. Black holes were also identified in a nonirradiated population, although the incidence was lower than in the post-brachytherapy patients. Bare metal stents were not associated with this phenomenon.

  2. Disseminated intravascular coagulation (DIC)

    MedlinePlus

    Levi M. Disseminated intravascular coagulation. In: Hoffman R, Benz EJ Jr, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice . 6th ed. Philadelphia, PA: Elsevier Saunders; 2013:chap ...

  3. Results of the Ticlid or Plavix Post-Stents (TOPPS) trial: do they justify the switch from ticlopidine to clopidogrel after coronary stent placement?

    PubMed

    Berger, Peter B

    2000-01-01

    In the Ticlid or Plavix Post-Stents (TOPPS) trial, 1016 patients undergoing successful coronary stent placement were randomized to receive aspirin and either ticlopidine or clopidogrel. In this trial, the dosages and regimens of ticlopidine and clopidogrel resembled more closely those used in most catheterization laboratories than did the two previous randomized trials comparing ticlopidine and clopidogrel. The results of the TOPPS trial support the current practice of substituting ticlopidine for clopidogrel in stent patients.

  4. Light intensity matching between different intravascular optical coherence tomography systems

    NASA Astrophysics Data System (ADS)

    Liu, Shengnan; Eggermont, Jeroen; Nakatani, Shimpei; Lelieveldt, Boudewijn P. F.; Dijkstra, Jouke

    2016-02-01

    Currently two commercial intravascular optical coherence tomography (IVOCT) systems are available: Illumien Optis from St. Jude Medical (SJM) and Lunawave from Terumo. Both systems store the light intensity data in a raw vendor specific polar format. However, whereas SJM uses 16-bits per pixel Terumo uses 8-bits meaning the intensity values are in different ranges. This complicates quantitative light intensity based analysis when comparing results based on data from both systems. Therefore, this work aims to find an intensity transformation function from Terumo's 8-bit OFDI data to SJM's 16-bit range. The data consists of 8 pullbacks, 4 acquired with each system in the same arteries of 2 different patents pre- and post-stenting implantation. A total of 133 matching sections without stent struts from the two sets of pullbacks were identified based on landmarks such as side-branches and calcified regions. Since the main region of interest in the image is the tissue region only the pixels within 2mm behind the lumen border are used. In order to match the SJM data range, the Terumo data was rescaled and cumulative distribution functions (CDF) were calculated based on the histogram distributions. Comparing these CDFs, the transformation function can be determined. Application of this transformation function not only improves the visual similarity of matching slices it can also be used for further quantitative analysis.

  5. Infections and intravascular devices.

    PubMed

    Elliott, T S; Faroqui, M H

    Complications associated with intravascular devices include infections mainly caused by Staphylococcus epidermis and S. aureus. The reported incidence of these infections varies. Several factors influence the propensity for catheter infections. We recommend strategies for the prevention and treatment of catheter-related sepsis. PMID:1422561

  6. Intravascular Photoacoustic Imaging

    PubMed Central

    Wang, Bo; Su, Jimmy L.; Karpiouk, Andrei B.; Sokolov, Konstantin V.; Smalling, Richard W.; Emelianov, Stanislav Y.

    2011-01-01

    Intravascular photoacoustic (IVPA) imaging is a catheter-based, minimally invasive, imaging modality capable of providing high-resolution optical absorption map of the arterial wall. Integrated with intravascular ultrasound (IVUS) imaging, combined IVPA and IVUS imaging can be used to detect and characterize atherosclerotic plaques building up in the inner lining of an artery. In this paper, we present and discuss various representative applications of combined IVPA/IVUS imaging of atherosclerosis, including assessment of the composition of atherosclerotic plaques, imaging of macrophages within the plaques, and molecular imaging of biomarkers associated with formation and development of plaques. In addition, imaging of coronary artery stents using IVPA and IVUS imaging is demonstrated. Furthermore, the design of an integrated IVUS/IVPA imaging catheter needed for in vivo clinical applications is discussed. PMID:21359138

  7. How Is Disseminated Intravascular Coagulation Treated?

    MedlinePlus

    ... the NHLBI on Twitter. How Is Disseminated Intravascular Coagulation Treated? Treatment for disseminated intravascular coagulation (DIC) depends ... and treat the underlying cause. Acute Disseminated Intravascular Coagulation People who have acute DIC may have severe ...

  8. Intravascular brachytherapy with radioactive stents produced by ion implantation

    NASA Astrophysics Data System (ADS)

    Golombeck, M.-A.; Heise, S.; Schloesser, K.; Schuessler, B.; Schweickert, H.

    2003-05-01

    About 1 million patients are treated for stenosis of coronary arteries by percutaneous balloon angioplasty annually worldwide. In many cases a so called stent is inserted into the vessel to keep it mechanically open. Restenosis is observed in about 20-30% of these cases, which can be treated by irradiating the stented vessel segment. In our approach, we utilized the stent itself as radiation source by ion implanting 32P. Investigations of the surface properties were performed with special emphasis on activity retention. Clinical data of about 400 patients showed radioactive stents can suppress instent restenosis, but a so called edge effect appeared, which can be avoided by the new "drug eluting stents".

  9. Disseminated intravascular coagulation.

    PubMed

    Gando, Satoshi; Levi, Marcel; Toh, Cheng-Hock

    2016-01-01

    Disseminated intravascular coagulation (DIC) is an acquired syndrome characterized by widespread intravascular activation of coagulation that can be caused by infectious insults (such as sepsis) and non-infectious insults (such as trauma). The main pathophysiological mechanisms of DIC are inflammatory cytokine-initiated activation of tissue factor-dependent coagulation, insufficient control of anticoagulant pathways and plasminogen activator inhibitor 1-mediated suppression of fibrinolysis. Together, these changes give rise to endothelial dysfunction and microvascular thrombosis, which can cause organ dysfunction and seriously affect patient prognosis. Recent observations have pointed to an important role for extracellular DNA and DNA-binding proteins, such as histones, in the pathogenesis of DIC. The International Society on Thrombosis and Haemostasis (ISTH) established a DIC diagnostic scoring system consisting of global haemostatic test parameters. This scoring system has now been well validated in diverse clinical settings. The theoretical cornerstone of DIC management is the specific and vigorous treatment of the underlying conditions, and DIC should be simultaneously managed to improve patient outcomes. The ISTH guidance for the treatment of DIC recommends treatment strategies that are based on current evidence. In this Primer, we provide an updated overview of the pathophysiology, diagnosis and management of DIC and discuss the future directions of basic and clinical research in this field. PMID:27250996

  10. Intravascular adenomyomatosis: expanding the morphologic spectrum of intravascular leiomyomatosis.

    PubMed

    Hirschowitz, Lynn; Mayall, Frederick G; Ganesan, Raji; McCluggage, W Glenn

    2013-09-01

    Intravascular leiomyomatosis (IVL) is characterized by the presence of smooth muscle in venous and lymphatic spaces within the myometrium. Although the intravascular component usually consists solely of typical smooth muscle or variants of smooth muscle differentiation, we report 5 cases in which the intravascular component also included endometrioid glandular and stromal elements. We propose the term "intravenous adenomyomatosis" to describe this unusual variant of IVL. The mean age of the patients in this series was 50.2 years, slightly older than that of patients with conventional IVL. In addition to intravenous adenomyomatosis, both adenomyosis and leiomyomas were identified in all of our cases, supporting the hypothesis that the intravascular smooth muscle component in IVL is derived from associated myometrial pathology rather than from vessel walls. In our series, intravenous adenomyomatosis had a similar benign clinical behavior to most cases of IVL with no metastatic or recurrent disease identified at follow-up in 4 cases for which follow-up information was available. The main differential diagnoses are adenomyosis with vascular involvement, low-grade endometrial stromal sarcoma (ESS), including ESS with smooth muscle and glandular differentiation, and adenosarcoma with lymphovascular invasion. The possibility of intravenous adenomyomatosis should be borne in mind when considering these diagnoses, particularly ESS and adenosarcoma, which have different implications for patient management and prognosis.

  11. Dosimetric audit in brachytherapy

    PubMed Central

    Bradley, D A; Nisbet, A

    2014-01-01

    Dosimetric audit is required for the improvement of patient safety in radiotherapy and to aid optimization of treatment. The reassurance that treatment is being delivered in line with accepted standards, that delivered doses are as prescribed and that quality improvement is enabled is as essential for brachytherapy as it is for the more commonly audited external beam radiotherapy. Dose measurement in brachytherapy is challenging owing to steep dose gradients and small scales, especially in the context of an audit. Several different approaches have been taken for audit measurement to date: thimble and well-type ionization chambers, thermoluminescent detectors, optically stimulated luminescence detectors, radiochromic film and alanine. In this work, we review all of the dosimetric brachytherapy audits that have been conducted in recent years, look at current audits in progress and propose required directions for brachytherapy dosimetric audit in the future. The concern over accurate source strength measurement may be essentially resolved with modern equipment and calibration methods, but brachytherapy is a rapidly developing field and dosimetric audit must keep pace. PMID:24807068

  12. [Safety in brachytherapy].

    PubMed

    Marcié, S; Marinello, G; Peiffert, D; Lartigau, É

    2013-04-01

    No technique can now be used without previously considering the safety of patients, staff and public and risk management. This is the case for brachytherapy. The various aspects of brachytherapy are discussed for both the patient and the staff. For all, the risks must be minimized while achieving a treatment of quality. It is therefore necessary to establish a list as comprehensive as possible regardless of the type of brachytherapy (low, high, pulsed dose-rate). Then, their importance must be assessed with the help of their criticality. Radiation protection of personnel and public must take into account the many existing regulation texts. Four axes have been defined for the risk management for patients: organization, preparation, planning and implementation of treatment. For each axis, a review of risks is presented, as well as administrative, technical and medical dispositions for staff and the public. PMID:23465784

  13. Patient effective dose from endovascular brachytherapy with 192Ir sources.

    PubMed

    Perma, L; Bianchi, C; Nicolini, G; Novario, R; Tanzi, F; Conte, L

    2002-01-01

    The growing use of endovascular brachytherapy has been accompanied by the publication of a large number of studies in several fields, but few studies on patient dose have been found in the literature. Moreover, these studies were carried out on the basis of Monte Carlo simulation. The aim of the present study was to estimate the effective dose to the patient undergoing endovascular brachytherapy treatment with 112Ir sources, by means of experimental measurements. Two standard treatments were taken into account: an endovascular brachytherapy of the coronary artery corresponding to the activity x time product of 184 GBq.min and an endovascular brachytherapy of the renal artery (898 GBq.min). Experimental assessment was accomplished by thermoluminescence dosemeters positioned in more than 300 measurement points in a properly adapted Rqndo phantom. A method has been developed to estimate the mean organ doses for all tissues and organs concerned in order to calculate the effective dose associated with intravascular brachytherapy. The normalised organ doses resulting from cronary treatment were 2.4 x 10(-2) mSv.GBq(-1).min(-1) for lung, 0.9 x 10(-2) mSv.GBSq(-1).min(-1) for oesophagus and 0.48 x 10(-2) mS.GBq(-1).min(-1) for bone marrow. During brachytherapy of the renal artery, the corresponding normalised doses were 4.2 x 10(-2) mS.GBq(-1).min(-1) for colon, 7.8 x 10(-2) mSv.GBq(-1).min(-1) for stomach and 1.7 x 10(-2) mSv.GBq(-1).min(-1) for liver. Coronary treatment iJnvlled an efl'fective dose of (0.046 mSv.GBq(-1).min(-1), whereas the treatment of the renal artery resulted in an effective dose of 0.15 mSv.GBq(-1).min(-1); there were many similarities with data from former studies. Based on these results it can be concluded that the dose level of patients exposed during brachytherapy treatment is low.

  14. Endosulfan poisoning with intravascular hemolysis.

    PubMed

    Ramaswamy, Shankar; Puri, Goverdhan Dutt; Rajeev, Subramanyam

    2008-04-01

    We describe a 26-year-old female patient, who had attempted suicide with Endosulfan, and who presented to the Emergency Department with status epilepticus. She subsequently developed hypotension refractory to inotropes, intravascular hemolysis, disseminated intravascular coagulation (DIC), metabolic acidosis and, finally, cardiac arrest and death. Endosulfan is a chlorinated insecticide that causes central nervous system hyperstimulation. It is absorbed from the gastrointestinal tract, skin, and respiratory tract, and leads to nausea, vomiting, paraesthesia, giddiness, convulsion, coma, respiratory failure, and congestive cardiac failure. Hepatic, renal and myocardial toxicity, agranulocytosis, aplastic anemia, cerebral edema, DIC, thrombocytopenia, and skin reaction also have been reported. Management includes decontamination of skin and gastrointestinal tract, supportive care including treatment of status epilepticus, dysrhythmias, and mechanical ventilation. Mortality and morbidity rates are very high and there is no specific antidote. Atropine and catecholamines should be avoided.

  15. Image Processing in Intravascular OCT

    NASA Astrophysics Data System (ADS)

    Wang, Zhao; Wilson, David L.; Bezerra, Hiram G.; Rollins, Andrew M.

    Coronary artery disease is the leading cause of death in the world. Intravascular optical coherence tomography (IVOCT) is rapidly becoming a promising imaging modality for characterization of atherosclerotic plaques and evaluation of coronary stenting. OCT has several unique advantages over alternative technologies, such as intravascular ultrasound (IVUS), due to its better resolution and contrast. For example, OCT is currently the only imaging modality that can measure the thickness of the fibrous cap of an atherosclerotic plaque in vivo. OCT also has the ability to accurately assess the coverage of individual stent struts by neointimal tissue over time. However, it is extremely time-consuming to analyze IVOCT images manually to derive quantitative diagnostic metrics. In this chapter, we introduce some computer-aided methods to automate the common IVOCT image analysis tasks.

  16. [High dose rate brachytherapy].

    PubMed

    Aisen, S; Carvalho, H A; Chavantes, M C; Esteves, S C; Haddad, C M; Permonian, A C; Taier, M do C; Marinheiro, R C; Feriancic, C V

    1992-01-01

    The high dose rate brachytherapy uses a single source os 192Ir with 10Ci of nominal activity in a remote afterloading machine. This technique allows an outpatient treatment, without the inconveniences of the conventional low dose rate brachytherapy such as use of general anesthesia, rhachianesthesia, prolonged immobilization, and personal exposition to radiation. The radiotherapy department is now studying 5 basic treatment schemes concerning carcinomas of the uterine cervix, endometrium, lung, esophagus and central nervous system tumors. With the Micro Selectron HDR, 257 treatment sessions were done in 90 patients. Mostly were treated with weekly fractions, receiving a total of three to four treatments each. No complications were observed neither during nor after the procedure. Doses, fraction and ideal associations still have to be studied, so that a higher therapeutic ratio can be reached.

  17. Fibrinolysis in disseminated intravascular coagulation.

    PubMed

    Hack, C E

    2001-12-01

    Studies in experimental models for sepsis, the most common cause of disseminated intravascular coagulation (DIC), have put forward the concept of a procoagulant state that is characterized by thrombin generation exceeding that of plasmin. Convincing evidence indicates that this imbalance between coagulation and fibrinolysis is due to increased levels of plasminogen activator inhibitor type 1 (PAI-1). Levels of this fibrinolysis inhibitor indeed correlate with outcome and severity of multiple organ failure in patients with sepsis, as well as in patients with DIC from other causes. Hence we suggest that PAI-1 constitutes an important target for therapy in patients with DIC.

  18. Salvage Brachytherapy for Biochemically Recurrent Prostate Cancer following Primary Brachytherapy

    PubMed Central

    Lacy, John M.; Wilson, William A.; Bole, Raevti; Chen, Li; Meigooni, Ali S.; Rowland, Randall G.; Clair, William H. St.

    2016-01-01

    Purpose. In this study, we evaluated our experience with salvage brachytherapy after discovery of biochemical recurrence after a prior brachytherapy procedure. Methods and Materials. From 2001 through 2012 twenty-one patients treated by brachytherapy within University of Kentucky or from outside centers developed biochemical failure and had no evidence of metastases. Computed tomography (CT) scans were evaluated; patients who had an underseeded portion of their prostate were considered for reimplantation. Results. The majority of the patients in this study (61.9%) were low risk and median presalvage PSA was 3.49 (range 17.41–1.68). Mean follow-up was 61 months. At last follow-up after reseeding, 11/21 (52.4%) were free of biochemical recurrence. There was a trend towards decreased freedom from biochemical recurrence in low risk patients (p = 0.12). International Prostate Symptom Scores (IPSS) increased at 3-month follow-up visits but decreased and were equivalent to baseline scores at 18 months. Conclusions. Salvage brachytherapy after primary brachytherapy is possible; however, in our experience the side-effect profile after the second brachytherapy procedure was higher than after the first brachytherapy procedure. In this cohort of patients we demonstrate that approximately 50% oncologic control, low risk patients appear to have better outcomes than others. PMID:27092279

  19. Acute Disseminated Intravascular Coagulation in Neuroendocrine Carcinoma

    PubMed Central

    Teh, Ru-Wen; Tsoi, Daphne T.

    2012-01-01

    Malignancy is a common cause of disseminated intravascular coagulation and usually presents as a chronic disorder in solid organ tumours. We present a rare case of recurrent acute disseminated intravascular coagulation in neuroendocrine carcinoma after manipulation, firstly, by core biopsy and, later, by cytotoxic therapy causing a release of procoagulants and cytokines from lysed tumour cells. This is reminiscent of tumour lysis syndrome where massive quantities of intracellular electrolytes and nucleic acid are released, causing acute metabolic imbalance and renal failure. This case highlights the potential complication of acute disseminated intravascular coagulation after trauma to malignant cells. PMID:23139666

  20. Disseminated intravascular coagulation in sepsis.

    PubMed

    Zeerleder, Sacha; Hack, C Erik; Wuillemin, Walter A

    2005-10-01

    Disseminated intravascular coagulation is a frequent complication of sepsis. Coagulation activation, inhibition of fibrinolysis, and consumption of coagulation inhibitors lead to a procoagulant state resulting in inadequate fibrin removal and fibrin deposition in the microvasculature. As a consequence, microvascular thrombosis contributes to promotion of organ dysfunction. Recently, three randomized, double-blind, placebo-controlled trials investigated the efficacy of antithrombin, activated protein C (APC), and tissue factor pathway inhibitor, respectively, in sepsis patients. A significant reduction in mortality was demonstrated in the APC trial. In this article, we first discuss the physiology of coagulation and fibrinolysis activation. Then, the pathophysiology of coagulation activation, consumption of coagulation inhibitors, and the inhibition of fibrinolysis leading to a procoagulant state are described in more detail. Moreover, therapeutic concepts as well as the three randomized, double-blind, placebo-controlled studies are discussed.

  1. Obstetrical disseminated intravascular coagulation score.

    PubMed

    Kobayashi, Takao

    2014-06-01

    Obstetrical disseminated intravascular coagulation (DIC) is usually a very acute, serious complication of pregnancy. The obstetrical DIC score helps with making a prompt diagnosis and starting treatment early. This DIC score, in which higher scores are given for clinical parameters rather than for laboratory parameters, has three components: (i) the underlying diseases; (ii) the clinical symptoms; and (iii) the laboratory findings (coagulation tests). It is justifiably appropriate to initiate therapy for DIC when the obstetrical DIC score reaches 8 points or more before obtaining the results of coagulation tests. Improvement of blood coagulation tests and clinical symptoms are essential to the efficacy evaluation for treatment after a diagnosis of obstetrical DIC. Therefore, the efficacy evaluation criteria for obstetrical DIC are also defined to enable follow-up of the clinical efficacy of DIC therapy.

  2. Treatment of Disseminated Intravascular Coagulation.

    PubMed

    Makruasi, Nisa

    2015-11-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic activation of blood coagulation, generation of thrombin, and leading to disturbance of the microvasculature. In this article, definition and diagnostic criteria of DIC depend on the International Society of Thrombosis and Haemostasis (ISTH). There is no gold standard for diagnosis of DIC, only low quality evidence is used in general practice. Many diagnostic tests and repeated measurement are required. For the treatment of DIC, there is no good quality evidence. The most important treatment for DIC is the specific treatment of the conditions associated DIC. Platelets and/or plasma transfusion may be also necessary if indicated. Nevertheless, there is no gold standard for diagnosis and treatment of DIC, we use only low quality evidence in general practice.

  3. Pulmonary intravascular lipid in neonatal necropsy specimens.

    PubMed

    Puntis, J W; Rushton, D I

    1991-01-01

    The lungs of 482 liveborn infants were examined at necropsy for the presence of intravascular lipid. Forty one patients had received parenteral feeding (including lipid emulsion in 30), and 441 had died before starting feeds or had received enteral feeds alone. Tissue was processed into wax and then stained with Sudan black; intravascular lipid was found in 15 of 30 infants who had received intravenous fat (Intralipid), but in no others. Those patients with positive lipid staining had received significantly more fat during parenteral nutrition than those in whom intravascular lipid was not found but the two groups were otherwise clinically indistinguishable. Using this staining technique intravascular lipid can be shown relatively often, although only in patients who have received intravenous lipid emulsion. The location of fat, predominantly in small pulmonary capillaries, and the absence of lipid emboli in other organs, suggests that lipid coalescence takes place before death and is not a postmortem artefact. The clinical relevance remains uncertain. PMID:1899990

  4. Pulmonary intravascular lipid in neonatal necropsy specimens.

    PubMed

    Puntis, J W; Rushton, D I

    1991-01-01

    The lungs of 482 liveborn infants were examined at necropsy for the presence of intravascular lipid. Forty one patients had received parenteral feeding (including lipid emulsion in 30), and 441 had died before starting feeds or had received enteral feeds alone. Tissue was processed into wax and then stained with Sudan black; intravascular lipid was found in 15 of 30 infants who had received intravenous fat (Intralipid), but in no others. Those patients with positive lipid staining had received significantly more fat during parenteral nutrition than those in whom intravascular lipid was not found but the two groups were otherwise clinically indistinguishable. Using this staining technique intravascular lipid can be shown relatively often, although only in patients who have received intravenous lipid emulsion. The location of fat, predominantly in small pulmonary capillaries, and the absence of lipid emboli in other organs, suggests that lipid coalescence takes place before death and is not a postmortem artefact. The clinical relevance remains uncertain.

  5. Recurrent abscess after MammoSite brachytherapy.

    PubMed

    Lopchinsky, Richard A; Giles, Kristina A

    2004-01-01

    Recently a new catheter was introduced to facilitate brachytherapy in a lumpectomy cavity. Data are limited on the side effects of high-dose brachytherapy to the lumpectomy cavity with the MammoSite catheter. We present a case of recurrent abscesses over a 7-month period in the lumpectomy cavity after MammoSite brachytherapy.

  6. [A method for studying intravascular platelet aggregation in vitro].

    PubMed

    Ikonnikova, E I; Chernousova, L A; Moshkina, I R

    1999-06-01

    A simple available method for evaluating intravascular platelet aggregation is proposed. It consists in graphic recording of disaggregation of platelet-rich citrate plasma, which indicates the degree of intravascular aggregation. Intravascular aggregation is notably increased in coronary patients and negligible in normal subjects. The method may be used for the diagnosis of diseases with a high thrombogenic risk.

  7. Brachytherapy in Gynecologic Cancers: Why Is It Underused?

    PubMed

    Han, Kathy; Viswanathan, Akila N

    2016-04-01

    Despite its established efficacy, brachytherapy is underused in the management of cervical and vaginal cancers in some parts of the world. Possible reasons for the underutilization of brachytherapy include the adoption of less invasive techniques, such as intensity-modulated radiotherapy; reimbursement policies favoring these techniques over brachytherapy; poor physician or patient access to brachytherapy; inadequate maintenance of brachytherapy skills among practicing radiation oncologists; transitioning to high-dose-rate (HDR) brachytherapy with increased time requirements; and insufficient training of radiation oncology residents.

  8. Utility of intravascular ultrasound in peripheral interventions.

    PubMed Central

    White, R A; Donayre, C E; Kopchok, G E; Walot, I; Mehringer, C M

    1997-01-01

    Endovascular imaging techniques encompass a variety of methods, including angiography, computed tomography, magnetic resonance imaging, angioscopy, and intravascular ultrasound. Each method provides unique information regarding the continuity of vascular structures and the morphology and distribution of lesions. Although arteriography has been the "gold standard" for imaging arterial anatomy, recent data have confirmed that even sophisticated arteriographic imaging substantially underestimates the degree of residual lesions, and that future observations and end-points for treatment will most likely be determined by data accumulated by computed tomography, magnetic resonance imaging, angioscopy, and intravascular ultrasound. Successful therapeutic applications of endovascular devices have developed because of improved patient selection using computed tomography, spiral computed tomography, magnetic resonance imaging, and computerized high-resolution angiography. Procedural success has been enhanced by improved mobile cinefluoroscopy, angioscopy, intraluminal ultrasound monitoring of angioplasty procedures, and the use of intravascular ultrasound for stent and stent-graft sizing and deployment. Newly developed methods and low-profile delivery systems enabling deployment and fixation of vascular prostheses by an endoluminal approach have heightened the interest of many interventionalists, particularly surgeons, in the use of endovascular surgical techniques. The evolution of this method promises to add a new dimension to the treatment of vascular lesions and relies heavily on the incorporation of miniaturized imaging systems, such as intravascular ultrasound, as a means to provide precise placement of devices. Images PMID:9068136

  9. [Possibilities for cardiac defibrillation using intravascular electrodes].

    PubMed

    Amosov, G G; Tolpekin, V E; Gasanov, E K; Fomichev, D I

    1987-05-01

    The efficiency of electric defibrillation of the heart was assessed in 17 experiments where the position of action electrodes varied. It is suggested that intravascular application of one electrode plus extravascular application of the other gives the optimum effect. The duration of unassisted reversible fibrillation averaged 3 minutes.

  10. Brachytherapy dosimeter with silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Moutinho, L. M.; Castro, I. F. C.; Peralta, L.; Abreu, M. C.; Veloso, J. F. C. A.

    2015-07-01

    In-vivo and in-situ measurement of the radiation dose administered during brachytherapy faces several technical challenges, requiring a very compact, tissue-equivalent, linear and highly sensitive dosimeter, particularly in low-dose rate brachytherapy procedures, which use radioactive seeds with low energy and low dose deposition rate. In this work we present a scintillating optical fiber dosimeter composed of a flexible sensitive probe and a dedicated electronic readout system based on silicon photomultiplier photodetection, capable of operating both in pulse and current modes. The performance of the scintillating fiber optic dosimeter was evaluated in low energy regimes, using an X-ray tube operating at voltages of 40-50 kV and currents below 1 mA, to assess minimum dose response of the scintillating fiber. The dosimeter shows a linear response with dose and is capable of detecting mGy dose variations like an ionization chamber. Besides fulfilling all the requirements for a dosimeter in brachytherapy, the high sensitivity of this device makes it a suitable candidate for application in low-dose rate brachytherapy. According to Peralta and Rego [1], the BCF-10 and BCF-60 scintillating optical fibers used in dosimetry exhibit high variations in their sensitivity for photon beams in the 25-100 kVp energy range. Energy linearity for energies below 50 keV needs to be further investigated, using monochromatic X-ray photons.

  11. Feasibility of functional imaging for brachytherapy

    PubMed Central

    2009-01-01

    This review summarizes the current understanding of the feasibility of functional imaging for brachytherapy. In following subsections the role of ultrasound, power doppler imaging, positron emission tomography, magnetic resonance imaging, dynamic dose calculation and targeted brachytherapy is analyzed. The combination of functional imaging with the new tools for intraoperative dose calculation and optimization opens new and exciting times in brachytherapy. New optimized protocols are needed and should be tested in controlled trials, to demonstrate an advantage of such a new paradigm.

  12. Image-based brachytherapy for cervical cancer.

    PubMed

    Vargo, John A; Beriwal, Sushil

    2014-12-10

    Cervical cancer is the third most common cancer in women worldwide; definitive radiation therapy and concurrent chemotherapy is the accepted standard of care for patients with node positive or locally advanced tumors > 4 cm. Brachytherapy is an important part of definitive radiotherapy shown to improve overall survival. While results for two-dimensional X-ray based brachytherapy have been good in terms of local control especially for early stage disease, unexplained toxicities and treatment failures remain. Improvements in brachytherapy planning have more recently paved the way for three-dimensional image-based brachytherapy with volumetric optimization which increases tumor control, reduces toxicity, and helps predict outcomes. Advantages of image-based brachytherapy include: improved tumor coverage (especially for large volume disease), decreased dose to critical organs (especially for small cervix), confirmation of applicator placement, and accounting for sigmoid colon dose. A number of modalities for image-based brachytherapy have emerged including: magnetic resonance imaging (MRI), computed tomography (CT), CT-MRI hybrid, and ultrasound with respective benefits and outcomes data. For practical application of image-based brachytherapy the Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology Working Group and American Brachytherapy Society working group guideline serve as invaluable tools, additionally here-in we outline our institutional clinical integration of these guidelines. While the body of literature supporting image-based brachytherapy continues to evolve a number of uncertainties and challenges remain including: applicator reconstruction, increasing resource/cost demands, mobile four-dimensional targets and organs-at-risk, and accurate contouring of "grey zones" to avoid marginal miss. Ongoing studies, including the prospective EMBRACE (an international study of MRI-guided brachytherapy in locally advanced cervical

  13. Intravascular access in pediatric cardiac arrest.

    PubMed

    Brunette, D D; Fischer, R

    1988-11-01

    All cases of patients aged less than 48 months who presented in cardiac arrest to the Hennepin County Medical Center's emergency department (ED) during the years 1984 to 1986 were reviewed retrospectively. The ED record, initial and subsequent chest radiographs, hospital charts, and autopsy reports were analyzed. A total of 33 cases were reviewed. The average patient age was 5 months. The average time needed to establish intravascular access was 7.9 +/- 4.2 minutes. Success rates were 77% for central venous catheterization, 81% for surgical vein cutdown, 83% for intraosseous infusion, and 17% for percutaneous peripheral catheterization. Percutaneous peripheral catheterization, when successful, and bone marrow needle placement were the fastest methods of obtaining intravascular access. There were no major immediate complications, and delayed complications were minimal. Attempts at peripheral intravenous catheter placement should be brief, with rapid progression to intraosseous infusion if peripheral attempts are not successful. PMID:3178949

  14. [Intravascular lymphoma: Report of one case].

    PubMed

    Young, Pablo; Massa, María; Finn, Bárbara C; Fleire, Gonzalo; Stemmelin, Germán R; Ruades, Amanda; Sutovsky, Daniel; Casas, José G; Dezanzo, Pablo; Vigovich, Félix; Bruetman, Julio E

    2015-08-01

    Intravascular lymphoma is a rare subtype of extranodal diffuse large B-cell lymphoma characterized by clonal proliferation of lymphocytes inside of small and medium caliber vessels. Its incidence is estimated at one case per million. The clinical picture is very variable, but frequently has skin and central nervous system involvement. It is diagnosed by demonstrating pathological blood vessel infiltration by lymphoma cells. We report a 44 years old male presenting with fever, malaise and erythematous lesions in the abdominal wall. An abdominal wall biopsy showed dilated vascular vessels with atypical cells in their lumen, compatible with large B-cell intravascular lymphoma. He was treated with rituximab, cyclophosphamide, adriamycin, vincristine and prednisone and an autologous hematopoietic stem cell transplantation, achieving a complete remission that has lasted two years. PMID:26436939

  15. Techniques for Intravascular Foreign Body Retrieval

    SciTech Connect

    Woodhouse, Joe B.; Uberoi, Raman

    2013-08-01

    As endovascular therapies increase in frequency, the incidence of lost or embolized foreign bodies is increasing. The presence of an intravascular foreign body (IFB) is well recognized to have the potential to cause serious complications. IFB can embolize and impact critical sites such as the heart, with subsequent significant morbidity or mortality. Intravascular foreign bodies most commonly result from embolized central line fragments, but they can originate from many sources, both iatrogenic and noniatrogenic. The percutaneous approach in removing an IFB is widely perceived as the best way to retrieve endovascular foreign bodies. This minimally invasive approach has a high success rate with a low associated morbidity, and it avoids the complications related to open surgical approaches. We examined the characteristics, causes, and incidence of endovascular embolizations and reviewed the various described techniques that have been used to facilitate subsequent explantation of such materials.

  16. [Disseminated intravascular coagulation in solid tumours].

    PubMed

    Ferrand, François Régis; Garcia-Hejl, Carine; Moussaid, Yassine; Schernberg, Antoine; Bidard, François-Clément; Pavic, Michel; Khenifer, Safia; Stoclin, Annabelle

    2014-06-01

    Disseminated intravascular coagulation (DIC) is a complex abnormality of hemostasis with dramatic consequences and long described as associated with tumors. Yet the diagnosis and management of paraneoplastic DIC are poorly defined. The purpose of this paper is to review DIC associated with solid tumors, at the pathophysiological and therapeutic levels in particular. We also report data from a recent retrospective series of patients with DIC in the context of a solid tumor, to illustrate the epidemiological, clinical and prognostic.

  17. Percutaneous Retrieval of Chronic Intravascular Foreign Bodies

    SciTech Connect

    Savage, Clare; Ozkan, Orhan S.; Walser, Eric M.; Wang Dongfang; Zwischenberger, Joseph B.

    2003-09-15

    To evaluate the feasibility of intravascular retrieval of chronic foreign bodies, we retrospectively reviewed an 8 year experience (1993-2001) of percutaneous retrieval of chronically retained intravascular foreign bodies (n = 6). In 6 of 6 cases (4 catheter fragments, 2 guidewires), 5-90 days elapsed before retrieval via the femoral or internal jugular vein. Under fluoroscopy, we determined the foreign body's course, position and size. A guidewire was advanced through a multipurpose catheter to the foreign body. The multipurpose catheter was replaced with a gooseneck snare catheter and the snare advanced to grasp and remove the foreign body. Percutaneous retrieval was successful in all 6 cases. One patient experienced mild hemoptysis, which resolved within 24 hr of observation. No patient experienced long-term sequelae. Given the potential life-threatening complications from intravascular foreign bodies and the low complication rate from percutaneous retrieval, we recommend extraction of the foreign body even if it is asymptomatic in the chronic setting (> 24 hr)

  18. Diagnosis and treatment of disseminated intravascular coagulation.

    PubMed

    Levi, M

    2014-06-01

    Disseminated intravascular coagulation (DIC) is a condition in which systemic activation of coagulation without a specific localization occurs, resulting in extensive formation of intravascular fibrin, particularly in small and midsize vessels. Disseminated intravascular coagulation may lead to several altered coagulation parameters, including a low platelet count, abnormal global clotting assays, low levels of physiological anticoagulant proteases, or increased fibrin degradation products. Also, more complex assays for activation of coagulation factors or pathways may indicate involvement of these molecules in DIC. None of these tests alone, however, can accurately ascertain or rebuff a diagnosis of DIC. Nonetheless, a combination of readily available routine assays may be instrumental in establishing a diagnosis of DIC and can also be useful to point to a subset of patients with DIC that may need definite, often costly, interventions in the hemostatic system. Current insights on relevant etiological pathways that may contribute to the occurrence of DIC have led to innovative therapeutic and adjunctive approaches to patient with DIC. Management options directed at the amelioration of hemostatic activation may tentatively be indicated and were found to be advantageous in experimental and clinical investigations. These treatments encompass elimination of tissue factor-mediated thrombin generation or restitution of normal anticoagulant function.

  19. Afterloading: The Technique That Rescued Brachytherapy

    SciTech Connect

    Aronowitz, Jesse N.

    2015-07-01

    Although brachytherapy had been established as a highly effective modality for the treatment of cancer, its application was threatened by mid-20th century due to appreciation of the radiation hazard to health care workers. This review examines how the introduction of afterloading eliminated exposure and ushered in a brachytherapy renaissance.

  20. Testicular shielding in penile brachytherapy

    PubMed Central

    Bindal, Arpita; Tambe, Chandrashekhar M.; Ghadi, Yogesh; Murthy, Vedang; Shrivastava, Shyam Kishore

    2015-01-01

    Purpose Penile cancer, although rare, is one of the common genitourinary cancers in India affecting mostly aged uncircumcised males. For patients presenting with small superficial lesions < 3 cm restricted to glans, surgery, radical external radiation or brachytherapy may be offered, the latter being preferred as it allows organ and function preservation. In patients receiving brachytherapy, testicular morbidity is not commonly addressed. With an aim to minimize and document the doses to testis after adequate shielding during radical interstitial brachytherapy for penile cancers, we undertook this study in 2 patients undergoing brachytherapy and forms the basis of this report. Material and methods Two patients with early stage penile cancer limited to the glans were treated with radical high-dose-rate (HDR) brachytherapy using interstitial implant. A total of 7-8 tubes were implanted in two planes, parallel to the penile shaft. A total dose of 44-48 Gy (55-60 Gy EQD2 doses with α/β = 10) was delivered in 11-12 fractions of 4 Gy each delivered twice daily. Lead sheets adding to 11 mm (4-5 half value layer) were interposed between the penile shaft and scrotum. The testicular dose was measured using thermoluminescent dosimeters. For each patient, dosimetry was done for 3 fractions and mean calculated. Results The cumulative testicular dose to left and right testis was 31.68 cGy and 42.79 cGy for patient A, and 21.96 cGy and 23.28 cGy for patient B. For the same patients, the mean cumulative dose measured at the posterior aspect of penile shaft was 722.15 cGy and 807.72 cGy, amounting to 16.4% and 16.8% of the prescribed dose. Hence, the application of lead shield 11 mm thick reduced testicular dose from 722-808 cGy to 21.96-42.57 cGy, an “absolute reduction” of 95.99 ± 1.5%. Conclusions With the use of a simple lead shield as described, we were able to effectively reduce testicular dose from “spermicidal” range to “oligospermic” range with possible

  1. Dynamic rotating-shield brachytherapy

    SciTech Connect

    Liu, Yunlong; Flynn, Ryan T.; Kim, Yusung; Yang, Wenjun; Wu, Xiaodong

    2013-12-15

    Purpose: To present dynamic rotating shield brachytherapy (D-RSBT), a novel form of high-dose-rate brachytherapy (HDR-BT) with electronic brachytherapy source, where the radiation shield is capable of changing emission angles during the radiation delivery process.Methods: A D-RSBT system uses two layers of independently rotating tungsten alloy shields, each with a 180° azimuthal emission angle. The D-RSBT planning is separated into two stages: anchor plan optimization and optimal sequencing. In the anchor plan optimization, anchor plans are generated by maximizing the D{sub 90} for the high-risk clinical-tumor-volume (HR-CTV) assuming a fixed azimuthal emission angle of 11.25°. In the optimal sequencing, treatment plans that most closely approximate the anchor plans under the delivery-time constraint will be efficiently computed. Treatment plans for five cervical cancer patients were generated for D-RSBT, single-shield RSBT (S-RSBT), and {sup 192}Ir-based intracavitary brachytherapy with supplementary interstitial brachytherapy (IS + ICBT) assuming five treatment fractions. External beam radiotherapy doses of 45 Gy in 25 fractions of 1.8 Gy each were accounted for. The high-risk clinical target volume (HR-CTV) doses were escalated such that the D{sub 2cc} of the rectum, sigmoid colon, or bladder reached its tolerance equivalent dose in 2 Gy fractions (EQD2 with α/β= 3 Gy) of 75 Gy, 75 Gy, or 90 Gy, respectively.Results: For the patients considered, IS + ICBT had an average total dwell time of 5.7 minutes/fraction (min/fx) assuming a 10 Ci{sup 192}Ir source, and the average HR-CTV D{sub 90} was 78.9 Gy. In order to match the HR-CTV D{sub 90} of IS + ICBT, D-RSBT required an average of 10.1 min/fx more delivery time, and S-RSBT required 6.7 min/fx more. If an additional 20 min/fx of delivery time is allowed beyond that of the IS + ICBT case, D-RSBT and S-RSBT increased the HR-CTV D{sub 90} above IS + ICBT by an average of 16.3 Gy and 9.1 Gy, respectively

  2. High dose rate brachytherapy for oral cancer

    PubMed Central

    YamazakI, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. PMID:23179377

  3. Hypothesis: Disseminated Intravascular Inflammation as the Inflammatory Counterpart to Disseminated Intravascular Coagulation

    NASA Astrophysics Data System (ADS)

    Bull, Brian S.; Bull, Maureen H.

    1994-08-01

    We have identified a leukocyte activation syndrome that is occasionally associated with the transfusion of intraoperatively recovered erythrocytes. This syndrome appears to result from intravascular damage caused by leukocytes activated during the erythrocyte salvage process. We hypothesize that this syndrome is part of a larger disease grouping: disseminated intravascular inflammation (DII). DII is the analog of the coagulation disorder disseminated intravascular coagulation. In disseminated intravascular coagulation, the organ damage results from uncontrolled activation of the clotting pathway; in DII the damage is caused by leukocytes that have become activated by direct contact with bacteria or in rare instances-such as erythrocyte salvage-in the absence of bacteria and bacterial products. Recent studies of the hazards associated with intraoperative blood salvage indicate that activation of leukocytes can be achieved by exposure to activated platelets alone. If such activated leukocytes are reinfused along with the washed erythrocytes, widespread organ damage may result. The lung is the organ most severely affected by activated leukocytes. Adult respiratory distress syndrome is one outcome. It is likely that DII is a presently unrecognized pathophysiological process that complicates a variety of primary disease states and increases their lethality.

  4. Multi-Frequency Intravascular Ultrasound (IVUS) Imaging

    PubMed Central

    Ma, Teng; Yu, Mingyue; Chen, Zeyu; Fei, Chunlong; Shung, K. Kirk; Zhou, Qifa

    2015-01-01

    Acute coronary syndrome (ACS) is frequently associated with the sudden rupture of a vulnerable atherosclerotic plaque within the coronary artery. Several unique physiological features, including a thin fibrous cap accompanied by a necrotic lipid core, are the targeted indicators for identifying the vulnerable plaques. Intravascular ultrasound (IVUS), a catheter-based imaging technology, has been routinely performed in clinics for more than 20 years to describe the morphology of the coronary artery and guide percutaneous coronary interventions. However, conventional IVUS cannot facilitate the risk assessment of ACS because of its intrinsic limitations, such as insufficient resolution. Renovation of the IVUS technology is essentially needed to overcome the limitations and enhance the coronary artery characterization. In this paper, a multi-frequency intravascular ultrasound (IVUS) imaging system was developed by incorporating a higher frequency IVUS transducer (80 to 150 MHz) with the conventional IVUS (30–50 MHz) system. The newly developed system maintains the advantage of deeply penetrating imaging with the conventional IVUS, while offering an improved higher resolution image with IVUS at a higher frequency. The prototyped multi-frequency catheter has a clinically compatible size of 0.95 mm and a favorable capability of automated image co-registration. In vitro human coronary artery imaging has demonstrated the feasibility and superiority of the multi-frequency IVUS imaging system to deliver a more comprehensive visualization of the coronary artery. This ultrasonic-only intravascular imaging technique, based on a moderate refinement of the conventional IVUS system, is not only cost-effective from the perspective of manufacturing and clinical practice, but also holds the promise of future translation into clinical benefits. PMID:25585394

  5. Disseminated intravascular coagulation in meningococcal sepsis. Case 7.

    PubMed

    Zeerleder, S; Zürcher Zenklusen, R; Hack, C E; Wuillemin, W A

    2003-08-01

    We report on a man (age: 49 years), who died from severe meningococcal sepsis with disseminated intravascular coagulation (DIC), multiple organ dysfunction syndrome and extended skin necrosis. We discuss in detail the pathophysiology of the activation of coagulation and fibrinolysis during sepsis. The article discusses new therapeutic concepts in the treatment of disseminated intravascular coagulation in meningococcal sepsis, too.

  6. Intravascular imaging with a storage phosphor detector

    NASA Astrophysics Data System (ADS)

    Shikhaliev, Polad M.; Petrek, Peter; Matthews, Kenneth L., II; Fritz, Shannon G.; Bujenovic, L. Steven; Xu, Tong

    2010-05-01

    The aim of this study is to develop and test an intravascular positron imaging system based on a storage phosphor detector for imaging and detecting vulnerable plaques of human coronary arteries. The radiotracer F18-FDG accumulates in vulnerable plaques with inflammation of the overlying cap. The vulnerable plaques can, therefore, be imaged by recording positrons emitted from F18-FDG with a detector inserted into the artery. A prototype intravascular detector was constructed based on storage phosphor. The detector uses a flexible storage phosphor tube with 55 mm length, 2 mm diameter and 0.28 mm wall thickness. The intravascular detector is guided into the vessel using x-ray fluoroscopy and the accumulated x-ray signal must be erased prior to positron imaging. For this purpose, a light diffuser, 0.9 mm in diameter and 55 mm in length, was inserted into the detector tube. The light diffuser was connected to a laser source through a 2 m long optical fiber. The diffuser redirected the 0.38 W laser light to the inner surface of the phosphor detector to erase it. A heart phantom with 300 cm3 volume and three coronary arteries with 3.2 mm diameter and with several plaques was constructed. FDG solution with 0.5 µCi cm-3 activity concentration was filled in the heart and coronary arteries. The detector was inserted in a coronary artery and the signal from the plaques and surrounding background activity was recorded for 2 min. Then the phosphor detector was extracted and read out using a storage phosphor reader. The light diffuser erased the signal resulting from fluoroscopic exposure to level below that encountered during positron imaging. Vulnerable plaques with area activities higher than 1.2 nCi mm-2 were visualized by the detector. This activity is a factor of 10-20 lower than that expected in human vulnerable plaques. The detector was able to image the internal surface of the coronary vessels with 50 mm length and 360° circumference. Spatial resolution was 0

  7. Positron autoradiography for intravascular imaging: feasibility evaluation

    NASA Astrophysics Data System (ADS)

    Shikhaliev, Polad M.; Xu, Tong; Ducote, Justin L.; Easwaramoorthy, Balasubramaniam; Mukherjee, Jogeshwar; Molloi, Sabee

    2006-02-01

    Approximately 70% of acute coronary artery disease is caused by unstable (vulnerable) plaques with an inflammation of the overlying cap and high lipid content. A rupturing of the inflamed cap of the plaque results in propagation of the thrombus into the lumen, blockage of the artery and acute ischaemic syndrome or sudden death. Morphological imaging such as angiography or intravascular ultrasound cannot determine inflammation status of the plaque. A radiotracer such as 18F-FDG is accumulated in vulnerable plaques due to higher metabolic activity of the inflamed cap and could be used to detect a vulnerable plaque. However, positron emission tomography (PET) cannot detect the FDG-labelled plaques because of respiratory and heart motions, small size and low activity of the plaques. Plaques can be detected using a miniature particle (positron) detector inserted into the artery. In this work, a new detector concept is investigated for intravascular imaging of the plaques. The detector consists of a storage phosphor tip bound to the end of an intravascular catheter. It can be inserted into an artery, absorb the 18F-FDG positrons from the plaques, withdrawn from the artery and read out. Length and diameter of the storage phosphor tip can be matched to the length and the diameter of the artery. Monte Carlo simulations and experimental evaluations of coronary plaque imaging with the proposed detector were performed. It was shown that the sensitivity of the storage phosphor detector to the positrons of 18F-FDG is sufficient to detect coronary plaques with 1 mm and 2 mm sizes and 590 Bq and 1180 Bq activities in the arteries with 2 mm and 3 mm diameters, respectively. An experimental study was performed using plastic tubes with 2 mm diameter filled with an FDG solution, which simulates blood. FDG spots simulating plaques were placed over the surface of the tube. A phosphor tip was inserted into the tube and imaged the plaques. Exposure time was 1 min in all simulations and

  8. International Standardization of the Clinical Dosimetry of Beta Radiation Brachytherapy Sources: Progress of an ISO Standard

    NASA Astrophysics Data System (ADS)

    Soares, Christopher

    2006-03-01

    In 2004 a new work item proposal (NWIP) was accepted by the International Organization for Standardization (ISO) Technical Committee 85 (TC85 -- Nuclear Energy), Subcommittee 2 (Radiation Protection) for the development of a standard for the clinical dosimetry of beta radiation sources used for brachytherapy. To develop this standard, a new Working Group (WG 22 - Ionizing Radiation Dosimetry and Protocols in Medical Applications) was formed. The standard is based on the work of an ad-hoc working group initiated by the Dosimetry task group of the Deutsches Insitiut für Normung (DIN). Initially the work was geared mainly towards the needs of intravascular brachytherapy, but with the decline of this application, more focus has been placed on the challenges of accurate dosimetry for the concave eye plaques used to treat ocular melanoma. Guidance is given for dosimetry formalisms, reference data to be used, calibrations, measurement methods, modeling, uncertainty determinations, treatment planning and reporting, and clinical quality control. The document is currently undergoing review by the ISO member bodies for acceptance as a Committee Draft (CD) with publication of the final standard expected by 2007. There are opportunities for other ISO standards for medical dosimetry within the framework of WG22.

  9. New intravascular flow sensor using fiber optics

    NASA Astrophysics Data System (ADS)

    Stenow, Erik N. D.

    1994-12-01

    A new sensor using fiber optics is suggested for blood flow measurements in small vessels. The sensor principle and a first evaluation on a flow model are presented. The new sensor uses small CO2 gas bubbles as flow markers for optical detection. When the bubbles pass an optical window, light emitted from one fiber is reflected and scattered into another fiber. The sensor has been proven to work in a 3 mm flow model using two 110 micrometers optical fibers and a 100 micrometers steel capillary inserted into a 1 mm guide wire. The evaluation of a sensor archetype shows that the new sensor provides a promising method for intravascular blood flow measurement in small vessels. The linearity for steady state flow is studied in the flow interval 30 - 130 ml/min. comparison with ultrasound Doppler flowmetry was performed for pulsatile flow in the interval 25 - 125 ml/min. with a pulse length between 0.5 and 2 s. The use of intravascular administered CO2 in small volumes is harmless because the gas is rapidly dissolved in whole blood.

  10. Pulsed liquid microjet for intravascular injection

    NASA Astrophysics Data System (ADS)

    Palanker, Daniel V.; Fletcher, Daniel A.; Miller, Jason; Huie, Philip; Marmor, Michael; Blumenkranz, Mark S.

    2002-06-01

    Occlusions of the retinal veins and arteries are associated with common diseases such as hypertension and arteriosclerosis and usually cause severe and irreversible loss of vision. Treatments for these vascular diseases have been unsatisfactory to date in part because of the difficulty of delivering thrombolytic drugs locally within the eye. In this article we describe a pulsed liquid microjet for minimally invasive intra-vascular drug delivery. The microjet is driven by a vapor bubble following an explosive evaporation of saline, produced by a microsecond-long electric discharge in front of the 25 micrometers electrode inside the micronozzle. Expansion of the transient vapor bubble produces a water jet with a diameter equal to the diameter of the nozzle, and with a velocity and duration that are controlled by the pulse energy. We found that fluid could be injected through the wall of a 60-micrometers -diameter artery in choriallantoic membrane using a 15-micrometers diameter liquid jet traveling at more than 60 m/s. Histological analysis of these arteries showed that the width of the perforation is limited to the diameter of the micronozzle, and the penetration depth of the jet is controlled by the discharge energy. The pulsed liquid microjet offers a promising technique for precise and needle-free intravascular delivery of thrombolytic drugs for localized treatment of retinal vascular occlusions.

  11. Fast integrated intravascular photoacoustic/ultrasound catheter

    NASA Astrophysics Data System (ADS)

    Choi, Changhoon; Cho, Seunghee; Kim, Taehoon; Park, Sungjo; Park, Hyoeun; Kim, Jinmoo; Lee, Seunghoon; Kang, Yeonsu; Jang, Kiyuk; Kim, Chulhong

    2016-03-01

    In cardiology, a vulnerable plaque is considered to be a key subject because it is strongly related to atherosclerosis and acute myocardial infarction. Because conventional intravascular imaging devices exhibit several limitations with regard to vulnerable plaque detection, the need for an effective lipid imaging modality has been continuously suggested. Photoacoustic (PA) imaging is a medical imaging technique with a high level of ultrasound (US) resolution and strong optical contrast. In this study, we successfully developed an integrated intravascular photoacoustic/ultrasound (IV-PAUS) imaging system with a catheter diameter of 1.2 mm for lipid-rich atherosclerosis imaging. An Nd:YAG pulsed laser with an excitation wavelength of 1064 nm was utilized. IV-PAUS offers 5-mm depth penetration and axial and lateral PA imaging resolutions of 94 μm and 203 μm, respectively, as determined by imaging a 6-μm carbon fiber. We initially obtained 3-dimensional (3D) co-registered PA/US images of metal stents. Subsequently, we successfully obtained 3D coregistered PA/US ex vivo images using an iliac artery from a rabbit atherosclerosis model. Accordingly, lipid-rich plaques were sufficiently differentiated from normal tissue in the ex vivo experiment. We validated these findings histologically to confirm the lipid content.

  12. Intravascular behavior of a perfluorochemical emulsion.

    PubMed

    Tsuda, Y; Yamanouchi, K; Okamoto, H; Yokoyama, K; Heldebrant, C

    1990-03-01

    The purpose of this study was to clarify the reason why two similar perfluorochemical (PFC) emulsions, namely a mixed PFC (perfluorodecalin: FDC and perfluorotripropylamine: FTPA) and an FDC emulsion, resulted in a very different survival time for the exchange-transfused rats. Supposing that some difference in the intravascular behavior of both emulsions would account for such a difference in efficacy, experiments on behavior of PFC emulsions were carried out focusing on the particle size. It was reconfirmed that larger PFC particles were eliminated from the blood stream much more rapidly than smaller particles with three FMIQ (perfluoro-N-methyldecahydroisoquinoline) emulsions. After the FDC + FTPA emulsion or the FDC emulsion were injected into rabbits, PFC particles in the blood tended to decrease in size. When each of the collected blood samples was incubated at 37 degrees C for 24 h, the FDC emulsion enlarged in size markedly, but the FDC + FTPA emulsion showed no change. The retention of PFC particles appeared to depend on the emulsion stability rather than simply on the emulsifying agent alone. These data showed that some differences were observed in intravascular persistence of the FDC + FTPA emulsion and the FDC emulsion, and suggested that the efficacy of PFC emulsions would reflect their behavior in the circulation. PMID:2374085

  13. Clinical implementation of a new electronic brachytherapy system for skin brachytherapy.

    PubMed

    Pons-Llanas, Olga; Ballester-Sánchez, Rosa; Celada-Álvarez, Francisco Javier; Candela-Juan, Cristian; García-Martínez, Teresa; Llavador-Ros, Margarita; Botella-Estrada, Rafael; Barker, Christopher A; Ballesta, Antonio; Tormo-Micó, Alejandro; Rodríguez, Silvia; Perez-Calatayud, Jose

    2015-01-01

    Although surgery is usually the first-line treatment for nonmelanoma skin cancers, radiotherapy (RT) may be indicated in selected cases. Radiation therapy as primary therapy can result in excellent control rates, cosmetics, and quality of life. Brachytherapy is a radiation treatment modality that offers the most conformal option to patients. A new modality for skin brachytherapy is electronic brachytherapy. This involves the placement of a high dose rate X-ray source directly in a skin applicator close to the skin surface, and therefore combines the benefits of brachytherapy with those of low energy X-ray radiotherapy. The Esteya electronic brachytherapy system is specifically designed for skin surface brachytherapy procedures. The purpose of this manuscript is to describe the clinical implementation of the new Esteya electronic brachytherapy system, which may provide guidance for users of this system. The information covered includes patient selection, treatment planning (depth evaluation and margin determination), patient marking, and setup. The justification for the hypofractionated regimen is described and compared with others protocols in the literature. Quality assurance (QA) aspects including daily testing are also included. We emphasize that these are guidelines, and clinical judgment and experience must always prevail in the care of patients, as with any medical treatment. We conclude that clinical implementation of the Esteya brachytherapy system is simple for patients and providers, and should allow for precise and safe treatment of nonmelanoma skin cancers. PMID:25834587

  14. Intravascular spill of hyperosmolar urea during induced midtrimester abortion.

    PubMed

    Kovasznay, B M; Burkman, R T; Atienza, M F; King, T M

    1979-01-01

    Intravascular spill of hypertonic sodium chloride and the resultant serious and occasionally fatal consquences have been reported in association with induced midtrimester abortion. This report details 3 cases of intravascular spill of hyperosmolar urea. Although urea may pose less concern, because of its ability to readily cross cell membranes and its action as an osmotic diuretic, inadvertent intravascular spill can produce symptoms that include nausea, headache, sensations of warmth, and intense uterine cramping. In addition, abnormal blood pigments may occasionally be noted in the urine. Treatment includes intravenous hydration, careful monitoring of fluid/electrolyte balance and renal function, and avoiding the use of oxytocic agents.

  15. Quinine-Induced Disseminated Intravascular Coagulation.

    PubMed

    Abed, Firas; Baniya, Ramkaji; Bachuwa, Ghassan

    2016-01-01

    Every drug comes with some side effect. It is the benefit/risk ratio that determines the medical use of the drug. Quinine, a known antimalarial drug, has been used for nocturnal leg cramps since the 1930s; it is associated with severe life-threatening hematological and cardiovascular side effects. Disseminated intravascular coagulation (DIC), albeit rare, is a known coagulopathy associated with Quinine. It is imperative to inquire about the Quinine intake in medication history in patients with coagulopathy, as most patients still consider it a harmless home remedy for nocturnal leg cramps. In this report, we present a case of coagulopathy in a middle-aged woman, who gave a history of taking Quinine for nocturnal leg cramps, as her home remedy. Early identification of the offending agent led to the diagnosis, prompt discontinuation of the medication, and complete recovery and prevented the future possibility of recurrence. PMID:27293443

  16. [Disseminated intravascular coagulation: clinical and biological diagnosis].

    PubMed

    Touaoussa, Aziz; El Youssi, Hind; El Hassani, Imane; Hanouf, Daham; El Bergui, Imane; Zoulati, Ghizlane; Amrani Hassani, Moncef

    2015-01-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by the systemic activation of blood coagulation. Its pathophysiological mechanisms are complex and dependent on the underlying pathology, making the clinical and biological expression of quite variable DIC. Among the various biological parameters disrupted, most are not specific, and none of them allows in itself to make the diagnosis. All this does not facilitate the task of the practitioner for diagnosis of overt DIC, much less that of the non-overt DIC, early stage whose treatment would improve the prognosis. These considerations have led to develop scores, combining several parameters depending on their availability in daily practice, as well as their diagnostic relevance. Of all the scores, the ISTH (International society of thrombosis and hemostasis) remains the most used.

  17. Disseminated intravascular coagulation in burn injury.

    PubMed

    Lippi, Giuseppe; Ippolito, Luigi; Cervellin, Gianfranco

    2010-06-01

    Disseminated intravascular coagulation (DIC) is a complex and multifaceted disorder characterized by the activation of coagulation and fibrinolytic pathways, consumption of coagulation factors, and depletion of coagulation regulatory proteins. The introduction into the circulation of cellular debris characterized by strong thromboplastic activity due to tissue factor exposition or release (in or from burned tissues), which can thereby activate extrinsic pathway of coagulation system and trigger massive thrombin generation when present in sufficient concentration, represents the most plausible biological explanation to support the development of intravascular coagulation in patients with burn injury. Severe burns left untreated might also lead to an immunological and inflammatory response (activation of the complement cascade), which can amplify fibrinolysis and blood clotting. Overall, the real prevalence of DIC in patients with burns is as yet unclear. Postmortem, retrospective, and even longitudinal investigations are in fact biased by several factors, such as the objective difficulty to establish whether DIC might have occurred as a primary complication of burns or rather as a consequence of other superimposed pathologies (e.g., sepsis, multiple organ failure), the different diagnostic criteria for assessing DIC, and the heterogeneity of the patient samples studied. Nevertheless, the current scientific evidence is consistent with the hypothesis that biochemical changes suggestive for DIC (hypercoagulability, hypo- and hyperfibrinolysis) are commonplace in patients with burn trauma, and their severity increases exponentially with the severity of injury. Overt DIC seems to occur especially in critically ill burn patients or in those with severe burns (up to third degree) and large involvement of body surface area, in whom an appropriate therapy might be effective to prevent the otherwise fulminant course. Although early prophylaxis with antithrombin concentrates

  18. Dosimetric Characteristics for Brachytherapy Sources

    SciTech Connect

    DeWerd, Larry A.; Davis, Stephen D.

    2011-05-05

    Brachytherapy sources are characterized by the dosimetric parameters in a protocol such as the American Association of Physicists in Medicine Task Group 43. The air-kerma strength is measured and traceable to a primary standard. Then the parameters such as dose-rate constant, radial dose function, and anisotropy function are measured and related back to the primary standard. This is normally accomplished with thermoluminescent dosimeters (TLDs). Since radial dose function and anisotropy function are relative parameters, some of the dosimetric corrections are negligible. For the dose-rate constant, parameters such as the energy dependence compared with a calibration beam such as {sup 60}Co need to be accounted for. A description of the primary standard measurements and TLD measurements will be discussed.

  19. In vivo dosimetry in brachytherapy

    SciTech Connect

    Tanderup, Kari; Beddar, Sam; Andersen, Claus E.; Kertzscher, Gustavo; Cygler, Joanna E.

    2013-07-15

    In vivo dosimetry (IVD) has been used in brachytherapy (BT) for decades with a number of different detectors and measurement technologies. However, IVD in BT has been subject to certain difficulties and complexities, in particular due to challenges of the high-gradient BT dose distribution and the large range of dose and dose rate. Due to these challenges, the sensitivity and specificity toward error detection has been limited, and IVD has mainly been restricted to detection of gross errors. Given these factors, routine use of IVD is currently limited in many departments. Although the impact of potential errors may be detrimental since treatments are typically administered in large fractions and with high-gradient-dose-distributions, BT is usually delivered without independent verification of the treatment delivery. This Vision 20/20 paper encourages improvements within BT safety by developments of IVD into an effective method of independent treatment verification.

  20. Brachytherapy next generation: robotic systems

    PubMed Central

    Popescu, Tiberiu; Kacsó, Alex Cristian; Pisla, Doina

    2015-01-01

    In a field dominated by external beam radiation therapy (EBRT), both the therapeutic and technical possibilities of brachytherapy (BT) are underrated, shadowed by protons and intensity modulated radiotherapy. Decreasing expertise and indications, as well as increasing lack of specific BT training for radiation therapy (RT) residents led to the real need of shortening its learning curve and making it more popular. Developing robotic BT devices can be a way to mitigate the above issues. There are many teams working at custom-made robotic BT platforms to perfect and overcome the limitations of the existing systems. This paper provides a picture of the current state-of-the-art in robotic assisted BT, as it also conveys the author's solution to the problem, a parallel robot that uses CT-guidance. PMID:26816510

  1. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radionuclide brachytherapy source. 892.5730... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5730 Radionuclide brachytherapy source. (a) Identification. A radionuclide brachytherapy source is a device that consists of...

  2. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.432 Calibration measurements of brachytherapy sources. (a) Before the first medical use of...

  3. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Radionuclide brachytherapy source. 892.5730... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5730 Radionuclide brachytherapy source. (a) Identification. A radionuclide brachytherapy source is a device that consists of...

  4. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.432 Calibration measurements of brachytherapy sources. (a) Before the first medical use of...

  5. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.406 Brachytherapy sources accountability. (a) A licensee shall maintain accountability at all...

  6. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.406 Brachytherapy sources accountability. (a) A licensee shall maintain accountability at all...

  7. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.432 Calibration measurements of brachytherapy sources. (a) Before the first medical use of...

  8. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.432 Calibration measurements of brachytherapy sources. (a) Before the first medical use of...

  9. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.432 Calibration measurements of brachytherapy sources. (a) Before the first medical use of...

  10. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.406 Brachytherapy sources accountability. (a) A licensee shall maintain accountability at all...

  11. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.406 Brachytherapy sources accountability. (a) A licensee shall maintain accountability at all...

  12. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Radionuclide brachytherapy source. 892.5730... (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Therapeutic Devices § 892.5730 Radionuclide brachytherapy source. (a) Identification. A radionuclide brachytherapy source is a device that consists of...

  13. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.406 Brachytherapy sources accountability. (a) A licensee shall maintain accountability at all...

  14. {sup 106}Ruthenium Brachytherapy for Retinoblastoma

    SciTech Connect

    Abouzeid, Hana; Moeckli, Raphael; Gaillard, Marie-Claire; Beck-Popovic, Maja; Pica, Alessia; Zografos, Leonidas; Balmer, Aubin; Pampallona, Sandro; Munier, Francis L.

    2008-07-01

    Purpose: To evaluate the efficacy of {sup 106}Ru plaque brachytherapy for the treatment of retinoblastoma. Methods and Materials: We reviewed a retrospective, noncomparative case series of 39 children with retinoblastoma treated with {sup 106}Ru plaques at the Jules-Gonin Eye Hospital between October 1992 and July 2006, with 12 months of follow-up. Results: A total of 63 tumors were treated with {sup 106}Ru brachytherapy in 41 eyes. The median patient age was 27 months. {sup 106}Ru brachytherapy was the first-line treatment for 3 tumors (4.8%), second-line treatment for 13 (20.6%), and salvage treatment for 47 tumors (74.6%) resistant to other treatment modalities. Overall tumor control was achieved in 73% at 1 year. Tumor recurrence at 12 months was observed in 2 (12.5%) of 16 tumors for which {sup 106}Ru brachytherapy was used as the first- or second-line treatment and in 15 (31.9%) of 47 tumors for which {sup 106}Ru brachytherapy was used as salvage treatment. Eye retention was achieved in 76% of cases (31 of 41 eyes). Univariate and multivariate analyses revealed no statistically significant risk factors for tumor recurrence. Radiation complications included retinal detachment in 7 (17.1%), proliferative retinopathy in 1 (2.4%), and subcapsular cataract in 4 (9.7%) of 41 eyes. Conclusion: {sup 106}Ru brachytherapy is an effective treatment for retinoblastoma, with few secondary complications. Local vitreous seeding can be successfully treated with {sup 106}Ru brachytherapy.

  15. 21 CFR 882.5150 - Intravascular occluding catheter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... Class III (premarket approval). (c) Date PMA or notice of completion of a PDP is required. A PMA or a... intravascular occluding catheter shall have an approved PMA or a declared completed PDP in effect before...

  16. 21 CFR 882.5150 - Intravascular occluding catheter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... Class III (premarket approval). (c) Date PMA or notice of completion of a PDP is required. A PMA or a... intravascular occluding catheter shall have an approved PMA or a declared completed PDP in effect before...

  17. Intravascular laser therapy in different forms of lung diseases

    NASA Astrophysics Data System (ADS)

    Kirillov, M. N.; Reshetnikov, V. A.; Kazhekin, O. A.; Shepelenko, A. F.

    1993-06-01

    The potentions of laser intravascular therapy in elimination of pyogenic and inflammatory intoxication in cases of acute pneumonia, pyo-destructive diseases (including posttraumatic diseases) of the lungs are studied clinically.

  18. Image guided Brachytherapy: The paradigm of Gynecologic and Partial Breast HDR Brachytherapy

    NASA Astrophysics Data System (ADS)

    Diamantopoulos, S.; Kantemiris, I.; Konidari, A.; Zaverdinos, P.

    2015-09-01

    High dose rate (HDR) brachytherapy uses high strength radioactive sources and temporary interstitial implants to conform the dose to target and minimize the treatment time. The advances of imaging technology enable accurate reconstruction of the implant and exact delineation of high-risk CTV and the surrounding critical structures. Furthermore, with sophisticated treatment planning systems, applicator devices and stepping source afterloaders, brachytherapy evolved to a more precise, safe and individualized treatment. At the Radiation Oncology Department of Metropolitan Hospital Athens, MRI guided HDR gynecologic (GYN) brachytherapy and accelerated partial breast irradiation (APBI) with brachytherapy are performed routinely. Contouring and treatment planning are based on the recommendations of the GEC - ESTRO Working group. The task of this presentation is to reveal the advantages of 3D image guided brachytherapy over 2D brachytherapy. Thus, two patients treated at our department (one GYN and one APBI) will be presented. The advantage of having adequate dose coverage of the high risk CTV and simultaneous low doses to the OARs when using 3D image- based brachytherapy will be presented. The treatment techniques, equipment issues, as well as implantation, imaging and treatment planning procedures will be described. Quality assurance checks will be treated separately.

  19. Intravascular probe for detection of vulnerable plaque

    NASA Astrophysics Data System (ADS)

    Patt, Bradley E.; Iwanczyk, Jan S.; MacDonald, Lawrence R.; Yamaguchi, Yuko; Tull, Carolyn R.; Janecek, Martin; Hoffman, Edward J.; Strauss, H. William; Tsugita, Ross; Ghazarossian, Vartan

    2001-12-01

    Coronary angiography is unable to define the status of the atheroma, and only measures the luminal dimensions of the blood vessel, without providing information about plaque content. Up to 70% of heart attacks are caused by minimally obstructive vulnerable plaques, which are too small to be detected adequately by angiography. We have developed an intravascular imaging detector to identify vulnerable coronary artery plaques. The detector works by sensing beta or conversion electron radiotracer emissions from plaque-binding radiotracers. The device overcomes the technical constraints of size, sensitivity and conformance to the intravascular environment. The detector at the distal end of the catheter uses six 7mm long by 0.5mm diameter scintillation fibers coupled to 1.5m long plastic fibers. The fibers are offset from each other longitudinally by 6mm and arranged spirally around a guide wire in the catheter. At the proximal end of the catheter the optical fibers are coupled to an interface box with a snap on connector. The interface box contains a position sensitive photomultiplier tube (PSPMT) to decode the individual fibers. The whole detector assembly fits into an 8-French (2.7 mm in diameter) catheter. The PSPMT image is further decoded with software to give a linear image, the total instantaneous count rate and an audio output whose tone corresponds to the count rate. The device was tested with F-18 and Tl-204 sources. Spectrometric response, spatial resolution, sensitivity and beta to background ratio were measured. System resolution is 6 mm and the sensitivity is >500 cps / micrometers Ci when the source is 1 mm from the detector. The beta to background ratio was 11.2 for F-18 measured on a single fiber. The current device will lead to a system allowing imaging of labeled vulnerable plaque in coronary arteries. This type of signature is expected to enable targeted and cost effective therapies to prevent acute coronary artery diseases such as: unstable angina

  20. Cardiac phase detection in intravascular ultrasound images

    NASA Astrophysics Data System (ADS)

    Matsumoto, Monica M. S.; Lemos, Pedro Alves; Yoneyama, Takashi; Furuie, Sergio Shiguemi

    2008-03-01

    Image gating is related to image modalities that involve quasi-periodic moving organs. Therefore, during intravascular ultrasound (IVUS) examination, there is cardiac movement interference. In this paper, we aim to obtain IVUS gated images based on the images themselves. This would allow the reconstruction of 3D coronaries with temporal accuracy for any cardiac phase, which is an advantage over the ECG-gated acquisition that shows a single one. It is also important for retrospective studies, as in existing IVUS databases there are no additional reference signals (ECG). From the images, we calculated signals based on average intensity (AI), and, from consecutive frames, average intensity difference (AID), cross-correlation coefficient (CC) and mutual information (MI). The process includes a wavelet-based filter step and ascendant zero-cross detection in order to obtain the phase information. Firstly, we tested 90 simulated sequences with 1025 frames each. Our method was able to achieve more than 95.0% of true positives and less than 2.3% of false positives ratio, for all signals. Afterwards, we tested in a real examination, with 897 frames and ECG as gold-standard. We achieved 97.4% of true positives (CC and MI), and 2.5% of false positives. For future works, methodology should be tested in wider range of IVUS examinations.

  1. Immunological characterization of pulmonary intravascular macrophages

    NASA Technical Reports Server (NTRS)

    Chitko-McKown, C. G.; Reddy, D. N.; Chapes, S. K.; McKown, R. D.; Blecha, F.; Spooner, B. S. (Principal Investigator)

    1992-01-01

    Pulmonary intravascular macrophages (PIMs) are lung macrophages found apposed to the endothelium of pulmonary capillaries. In many species, they are responsible for the clearance of blood-borne particulates and pathogens; however, little else is known about their roles as immunologic effector cells. We compared PIMs with pulmonary alveolar macrophages (PAMs) to determine the relative immunological activities of these two cell populations. Our results suggested that both populations possess similar phagocytic and bactericidal activities. In assays measuring cytotoxicity, PIMs were more cytotoxic than PAMs against virally infected target cells; however, differences between these macrophage populations were not as marked when noninfected targets were used. LPS-stimulated PIMs produced more T-cell proliferative cytokines than PAMs, and both populations of nonstimulated macrophages produced similar amounts of the cytokines. In contrast, PAMs produced more TNF alpha and NO2- than PIMs when both populations were stimulated with LPS; however, nonstimulated PAMs and PIMs produced similar amounts of TNF alpha and NO2. These data suggest that bovine PIMs are immunologically active. Differences between the degrees of activity of PIMs and PAMs indicate that these macrophage populations may have different roles in lung surveillance.

  2. [Infection prevention and control in intravascular devices].

    PubMed

    Colombo, D; Russolillo, C

    2003-04-01

    Intravascular devices (IVD) are indispensable in the care of the critical patient; even so, their use can be complicated by infection, which is generally associated with longer hospital stay and ensuing higher hospital costs. It is therefore imperative that guidelines are applied that constitute a basis of information upon which the individual facility can develop its own strategy. The strategy can be outlined under the following points: a) staff training, b) surveillance of IVD-associated infections, c) hand washing, d) barrier measures during catheter introduction and management, e) insertion site management and medication systems for the insertion site, f) choice and replacement of the IVD, g) replacement of intravenous administration devices and liquids, h) antimicrobial prophylaxis. In the management of central venous catheters (CVC), recommendations call for: 1) the use of a single lumen CVC, unless multiple accesses are needed; 2) the peripheral placement of CVCs, both in the use of tunneled catheters and/or implantable vascular devices in patients over 4 years of age in which long-term vascular access (> 30 days) is planned; 3) the use of completely implantable devices in pediatric patients less than 4 years of age requiring long-term vascular access; 4) the use of the subclavian artery as the site of CVC insertion unless clinically contraindicated (e.g. coagulopathy, anatomic alterations); 5) the application of barrier precautions during CVC introduction and in the management of the catheter and the insertion site. PMID:12766724

  3. Laboratory testing in disseminated intravascular coagulation.

    PubMed

    Favaloro, Emmanuel J

    2010-06-01

    The diagnosis of disseminated intravascular coagulation (DIC) relies on clinical signs and symptoms, identification of the underlying disease, the results of laboratory testing, and differentiation from other pathologies. The clinical features mainly depend on the underlying cause of the DIC. The laboratory diagnosis of DIC uses a combination of tests because no single test result alone can firmly establish or rule out the diagnosis. Global tests of hemostasis may initially provide evidence of coagulation activation and later in the process provide evidence of consumption of coagulation factors, but their individual diagnostic efficiency is limited. Fibrinolytic markers, in particular D-dimer, are reflective of activation of both coagulation and fibrinolysis, so that a normal finding can be useful for ruling-out DIC. Decreased levels of the natural anticoagulants (in particular, antithrombin and protein C) are frequently observed in patients with DIC, but their measurement is not normally incorporated into standard diagnostic algorithms. New tests are being explored for utility in DIC, and some additional tests may be useful on a case-by-case basis, depending on the proposed cause of the DIC or their local availability. For example, clot waveform analysis is useful but currently limited to a single instrument. Also, procalcitonin is an inflammatory biomarker that may be useful within the context of septic DIC, and activated factor X clotting time is an emerging test of procoagulant phospholipids that also seems to hold promise in DIC.

  4. Intravascular Neural Interface with Nanowire Electrode

    PubMed Central

    Watanabe, Hirobumi; Takahashi, Hirokazu; Nakao, Masayuki; Walton, Kerry; Llinás, Rodolfo R.

    2010-01-01

    Summary A minimally invasive electrical recording and stimulating technique capable of simultaneously monitoring the activity of a significant number (e.g., 103 to 104) of neurons is an absolute prerequisite in developing an effective brain–machine interface. Although there are many excellent methodologies for recording single or multiple neurons, there has been no methodology for accessing large numbers of cells in a behaving experimental animal or human individual. Brain vascular parenchyma is a promising candidate for addressing this problem. It has been proposed [1, 2] that a multitude of nanowire electrodes introduced into the central nervous system through the vascular system to address any brain area may be a possible solution. In this study we implement a design for such microcatheter for ex vivo experiments. Using Wollaston platinum wire, we design a submicron-scale electrode and develop a fabrication method. We then evaluate the mechanical properties of the electrode in a flow when passing through the intricacies of the capillary bed in ex vivo Xenopus laevis experiments. Furthermore, we demonstrate the feasibility of intravascular recording in the spinal cord of Xenopus laevis. PMID:21572940

  5. Endotoxin Induced Disseminated Intravascular Coagulation in Cattle

    PubMed Central

    Thomson, G. W.; McSherry, B. J.; Valli, V. E. O.

    1974-01-01

    Endotoxin administered intravenously to a group of four calves resulted in disseminated intravascular coagulation. A sublethal dose of piromen, a commercially available Pseudomonas spp endotoxin, was used. Serial measurements of total plasma fibrinogen, soluble fibrin levels, ethanol gelation tests, protamine sulfate tests, fibrinogen-fibrin-related antigen (FR-antigen) and prothrombin and thrombin times were done. Initial depression of plasma fibrinogen with a nadir of about 40% of pre-endotoxin levels at eight to 11 hours post-endotoxin (+8 to +11 hours) followed by an overcompensation to 180% at +60 to +108 hours was shown. Soluble fibrin was demonstrated in plasma from +2 to +22 hours with a peak of 100-114 mg/100 ml at +4 to +9 hours. Positive plasma ethanol gelation and protamine sulfate tests, as well as the presence of serum FR-antigen, occurred consistently following endotoxin administration. Significant increases in prothrombin times (PT) from +4 to +40 hours and in thrombin times (TT) from +4 to +16 hours were demonstrated. The peak increase of PT at +8 to +10 hours was 180%. The peak increase of TT at +6 to +9 hours was 260-290%. ImagesFig. 1.Fig. 2.Fig. 3.Fig. 4. PMID:4279765

  6. The basics of intravascular optical coherence tomography.

    PubMed

    Roleder, Tomasz; Jąkała, Jacek; Kałuża, Grzegorz L; Partyka, Łukasz; Proniewska, Klaudia; Pociask, Elżbieta; Zasada, Wojciech; Wojakowski, Wojciech; Gąsior, Zbigniew; Dudek, Dariusz

    2015-01-01

    Optical coherence tomography (OCT) has opened new horizons for intravascular coronary imaging. It utilizes near-infrared light to provide a microscopic insight into the pathology of coronary arteries in vivo. Optical coherence tomography is also capable of identifying the chemical composition of atherosclerotic plaques and detecting traits of their vulnerability. At present it is the only tool to measure the thickness of the fibrous cap covering the lipid core of the atheroma, and thus it is an exceptional modality to detect plaques that are prone to rupture (thin fibrous cap atheromas). Moreover, it facilitates distinguishing between plaque rupture and plaque erosion as a cause of acute intracoronary thrombosis. Optical coherence tomography is applied to guide angioplasties of coronary lesions and to assess outcomes of percutaneous coronary interventions broadly. It identifies stent malapposition, dissections, and thrombosis with unprecedented precision. Furthermore, OCT helps to monitor vessel healing after stenting. It evaluates the coverage of stent struts by the neointima and detects in-stent neoatherosclerosis. With so much potential, new studies are warranted to determine OCT's clinical impact. The following review presents the technical background, basics of OCT image interpretation, and practical tips for adequate OCT imaging, and outlines its established and potential clinical application.

  7. Rotational multispectral fluorescence lifetime imaging and intravascular ultrasound: bimodal system for intravascular applications

    PubMed Central

    Ma, Dinglong; Bec, Julien; Yankelevich, Diego R.; Gorpas, Dimitris; Fatakdawala, Hussain; Marcu, Laura

    2014-01-01

    Abstract. We report the development and validation of a hybrid intravascular diagnostic system combining multispectral fluorescence lifetime imaging (FLIm) and intravascular ultrasound (IVUS) for cardiovascular imaging applications. A prototype FLIm system based on fluorescence pulse sampling technique providing information on artery biochemical composition was integrated with a commercial IVUS system providing information on artery morphology. A customized 3-Fr bimodal catheter combining a rotational side-view fiberoptic and a 40-MHz IVUS transducer was constructed for sequential helical scanning (rotation and pullback) of tubular structures. Validation of this bimodal approach was conducted in pig heart coronary arteries. Spatial resolution, fluorescence detection efficiency, pulse broadening effect, and lifetime measurement variability of the FLIm system were systematically evaluated. Current results show that this system is capable of temporarily resolving the fluorescence emission simultaneously in multiple spectral channels in a single pullback sequence. Accurate measurements of fluorescence decay characteristics from arterial segments can be obtained rapidly (e.g., 20 mm in 5 s), and accurate co-registration of fluorescence and ultrasound features can be achieved. The current finding demonstrates the compatibility of FLIm instrumentation with in vivo clinical investigations and its potential to complement conventional IVUS during catheterization procedures. PMID:24898604

  8. Quantitative blood speed imaging with intravascular ultrasound.

    PubMed

    Crowe, J R; O'Donnell, M

    2001-03-01

    Previously, we presented a method of real-time arterial color flow imaging using an intravascular ultrasound (IVUS) imaging system, where real-time RF A-scans were processed with an FIR (finite-impulse response) filter bank to estimate relative blood speed. Although qualitative flow measurements are clinically valuable, realizing the full potential of blood flow imaging requires quantitative flow speed and volume measurements in real time. Unfortunately, the rate of RF echo-to-echo decorrelation is not directly related to scatterer speed in a side-looking IVUS system because the elevational extent of the imaging slice varies with range. Consequently, flow imaging methods using any type of decorrelation processing to estimate blood speed without accounting for spatial variation of the radiation pattern will have estimation errors that prohibit accurate comparison of speed estimates from different depths. The FIR filter bank approach measures the rate of change of the ultrasound signal by estimating the slow-time spectrum of RF echoes. A filter bank of M bandpass filters is applied in parallel to estimate M components of the slow-time DFT (discrete Fourier transform). The relationship between the slow-time spectrum, aperture diffraction pattern, and scatterer speed is derived for a simplified target. Because the ultimate goal of this work is to make quantitative speed measurements, we present a method to map slow time spectral characteristics to a quantitative estimate. Results of the speed estimator are shown for a simulated circumferential catheter array insonifying blood moving uniformly past the array (i.e., plug flow) and blood moving with a parabolic profile (i.e., laminar flow). PMID:11370361

  9. An Open System for Intravascular Ultrasound Imaging

    PubMed Central

    Qiu, Weibao; Chen, Yan; Li, Xiang; Yu, Yanyan; Cheng, Wang Fai; Tsang, Fu Keung; Zhou, Qifa; Shung, K. Kirk; Dai, Jiyan; Sun, Lei

    2013-01-01

    Visualization of the blood vessels can provide valuable morphological information for diagnosis and therapy strategies for cardiovascular disease. Intravascular ultrasound (IVUS) is able to delineate internal structures of vessel wall with fine spatial resolution. However, the developed IVUS is insufficient to identify the fibrous cap thickness and tissue composition of atherosclerotic lesions. Novel imaging strategies have been proposed, such as increasing the center frequency of ultrasound or using a modulated excitation technique to improve the accuracy of diagnosis. Dual-mode tomography combining IVUS with optical tomography has also been developed to determine tissue morphology and characteristics. The implementation of these new imaging methods requires an open system that allows users to customize the system for various studies. This paper presents the development of an IVUS system that has open structures to support various imaging strategies. The system design is based on electronic components and printed circuit board, and provides reconfigurable hardware implementation, programmable image processing algorithms, flexible imaging control, and raw RF data acquisition. In addition, the proposed IVUS system utilized a miniaturized ultrasound transducer constructed using PMN-PT single crystal for better piezoelectric constant and electromechanical coupling coefficient than traditional lead zirconate titanate (PZT) ceramics. Testing results showed that the IVUS system could offer a minimum detectable signal of 25 μV, allowing a 51 dB dynamic range at 47 dB gain, with a frequency range from 20 to 80 MHz. Finally, phantom imaging, in vitro IVUS vessel imaging, and multimodality imaging with photoacoustics were conducted to demonstrate the performance of the open system. PMID:23143570

  10. Early voiding dysfunction associated with prostate brachytherapy.

    PubMed

    Wagner; Nag; Young; Bahnson

    2000-12-15

    Introduction: Transperineal prostate brachytherapy is gaining popularity as a treatment for clinically localized carcinoma of the prostate. Very little prospective data exists addressing the issue of complications associated with this procedure. We present an analysis of the early voiding dysfunction associated with prostate brachytherapy. Materials and Methods: Forty-six consecutive patients who underwent Palladium-103 (Pd-103) seed placement for clinically localized prostate carcinoma were evaluated prospectively for any morbidity associated with the procedure. Twenty-three patients completed an International Prostate Symptom Score (IPSS) questionnaire preoperatively, at their first postoperative visit, and at their second postoperative visit. The total IPSS, each of the seven individual components, and the "bother" score were evaluated separately for each visit, and statistical significance was determined. Results: Urinary retention occurred in 7/46 patients (15%). Of these, 5 were able to void spontaneously after catheter removal. One patient is maintained with a suprapubic tube, and one patient is currently on continuous intermittent catheterization. Baseline IPSS was 7.1 and this went to 20.0 at the first postoperative visit (p<0.001). By the second postoperative visit, the IPSS was 8.0. Conclusions: In our experience, prostate brachytherapy for localized carcinoma of the prostate is associated with a 15% catheterization rate and a significant increase in the IPSS (7.1 to 20.0). This increase in the IPSS seems to be self-limited. Patients need to be educated on these issues prior to prostate brachytherapy. PMID:11113369

  11. The American Brachytherapy Society Treatment Recommendations for Locally Advanced Carcinoma of the Cervix Part II: High Dose-Rate Brachytherapy

    PubMed Central

    Viswanathan, Akila N.; Beriwal, Sushil; De Los Santos, Jennifer; Demanes, D. Jeffrey; Gaffney, David; Hansen, Jorgen; Jones, Ellen; Kirisits, Christian; Thomadsen, Bruce; Erickson, Beth

    2012-01-01

    Purpose This report presents the 2011 update to the American Brachytherapy Society (ABS) high-dose-rate (HDR) brachytherapy guidelines for locally advanced cervical cancer. Methods Members of the American Brachytherapy Society (ABS) with expertise in cervical cancer brachytherapy formulated updated guidelines for HDR brachytherapy using tandem and ring, ovoids, cylinder or interstitial applicators for locally advanced cervical cancer were revised based on medical evidence in the literature and input of clinical experts in gynecologic brachytherapy. Results The Cervical Cancer Committee for Guideline Development affirms the essential curative role of tandem-based brachytherapy in the management of locally advanced cervical cancer. Proper applicator selection, insertion, and imaging are fundamental aspects of the procedure. Three-dimensional imaging with magnetic resonance or computed tomography or radiographic imaging may be used for treatment planning. Dosimetry must be performed after each insertion prior to treatment delivery. Applicator placement, dose specification and dose fractionation must be documented, quality assurance measures must be performed, and follow-up information must be obtained. A variety of dose/fractionation schedules and methods for integrating brachytherapy with external-beam radiation exist. The recommended tumor dose in 2 Gray (Gy) per fraction radiobiologic equivalence (EQD2) is 80–90 Gy, depending on tumor size at the time of brachytherapy. Dose limits for normal tissues are discussed. Conclusion These guidelines update those of 2000 and provide a comprehensive description of HDR cervical cancer brachytherapy in 2011. PMID:22265437

  12. A Review of Intravascular Ultrasound–Based Multimodal Intravascular Imaging: The Synergistic Approach to Characterizing Vulnerable Plaques

    PubMed Central

    Ma, Teng; Zhou, Bill; Hsiai, Tzung K.; Shung, K. Kirk

    2015-01-01

    Catheter-based intravascular imaging modalities are being developed to visualize pathologies in coronary arteries, such as high-risk vulnerable atherosclerotic plaques known as thin-cap fibroatheroma, to guide therapeutic strategy at preventing heart attacks. Mounting evidences have shown three distinctive histopathological features—the presence of a thin fibrous cap, a lipid-rich necrotic core, and numerous infiltrating macrophages—are key markers of increased vulnerability in atherosclerotic plaques. To visualize these changes, the majority of catheter-based imaging modalities used intravascular ultrasound (IVUS) as the technical foundation and integrated emerging intravascular imaging techniques to enhance the characterization of vulnerable plaques. However, no current imaging technology is the unequivocal “gold standard” for the diagnosis of vulnerable atherosclerotic plaques. Each intravascular imaging technology possesses its own unique features that yield valuable information although encumbered by inherent limitations not seen in other modalities. In this context, the aim of this review is to discuss current scientific innovations, technical challenges, and prospective strategies in the development of IVUS-based multi-modality intravascular imaging systems aimed at assessing atherosclerotic plaque vulnerability. PMID:26400676

  13. Management of cancer-associated disseminated intravascular coagulation.

    PubMed

    Levi, Marcel

    2016-04-01

    Cancer may be complicated by the occurrence of disseminated intravascular coagulation (DIC). DIC is characterized by a widespread and intravascular activation of coagulation (leading to intravascular fibrin deposition) and simultaneous consumption of coagulation factors and platelets (potentially resulting in bleeding). Clinically, DIC in cancer has in general a less fulminant presentation than the types of DIC complicating sepsis and trauma. A more gradual, but also more chronic, systemic activation of coagulation can proceed subclinically. Eventually this process may lead to exhaustion of platelets and coagulation factors and bleeding (for example at the site of the tumor) may be the first clinical symptom indicating the presence of DIC. In some cases, the clinical presentation of DIC in cancer may be reminiscent of thrombotic microangiopathies, which is understandable in view of the role of endothelium in both conditions. The therapeutic cornerstone of DIC is treatment of the underlying disorder but supportive treatment, specifically aimed at the hemostatic system may be required. PMID:27067981

  14. 21 CFR 880.5970 - Percutaneous, implanted, long-term intravascular catheter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Percutaneous, implanted, long-term intravascular... and Personal Use Therapeutic Devices § 880.5970 Percutaneous, implanted, long-term intravascular catheter. (a) Identification. A percutaneous, implanted, long-term intravascular catheter is a device...

  15. Automated intraoperative calibration for prostate cancer brachytherapy

    SciTech Connect

    Kuiran Chen, Thomas; Heffter, Tamas; Lasso, Andras; Pinter, Csaba; Abolmaesumi, Purang; Burdette, E. Clif; Fichtinger, Gabor

    2011-11-15

    Purpose: Prostate cancer brachytherapy relies on an accurate spatial registration between the implant needles and the TRUS image, called ''calibration''. The authors propose a new device and a fast, automatic method to calibrate the brachytherapy system in the operating room, with instant error feedback. Methods: A device was CAD-designed and precision-engineered, which mechanically couples a calibration phantom with an exact replica of the standard brachytherapy template. From real-time TRUS images acquired from the calibration device and processed by the calibration system, the coordinate transformation between the brachytherapy template and the TRUS images was computed automatically. The system instantly generated a report of the target reconstruction accuracy based on the current calibration outcome. Results: Four types of validation tests were conducted. First, 50 independent, real-time calibration trials yielded an average of 0.57 {+-} 0.13 mm line reconstruction error (LRE) relative to ground truth. Second, the averaged LRE was 0.37 {+-} 0.25 mm relative to ground truth in tests with six different commercial TRUS scanners operating at similar imaging settings. Furthermore, testing with five different commercial stepper systems yielded an average of 0.29 {+-} 0.16 mm LRE relative to ground truth. Finally, the system achieved an average of 0.56 {+-} 0.27 mm target registration error (TRE) relative to ground truth in needle insertion tests through the template in a water tank. Conclusions: The proposed automatic, intraoperative calibration system for prostate cancer brachytherapy has achieved high accuracy, precision, and robustness.

  16. Brachytherapy in pelvic malignancies: a review for radiologists.

    PubMed

    Vicens, Rafael A; Rodriguez, Joshua; Sheplan, Lawrence; Mayo, Cody; Mayo, Lauren; Jensen, Corey

    2015-10-01

    Brachytherapy, also known as sealed source or internal radiation therapy, involves placement of a radioactive source immediately adjacent to or within tumor, thus enabling delivery of a localized high dose of radiation. Compared with external beam radiation which must first pass through non-target tissues, brachytherapy results in less radiation dose to normal tissues. In the past decade, brachytherapy use has markedly increased, thus radiologists are encountering brachytherapy devices and their associated post-treatment changes to increasing degree. This review will present a variety of brachytherapy devices that radiologists may encounter during diagnostic pelvic imaging with a focus on prostate and gynecologic malignancies. The reader will become familiar with the function, correct position, and potential complications of brachytherapy devices in an effort to improve diagnostic reporting and communication with clinicians.

  17. Incidental Intravascular Lipoleiomyomatosis in A Hysterectomy Specimen: How To Manage?

    PubMed Central

    Aslanova, Rakhshanda; Can, Nuray; Okten, Sabri Berkem; Aslan, Mehmet Musa

    2015-01-01

    Leiomyomas are common benign tumors in female gynaecologic surgery. They are originated from smooth muscle cells of the uterus and/or sometimes of the uterine vessels. Intravascular lipoleiomyomatosis is a very rare form of leiomyomas which grow within veins and can extend up to vena cava inferior and right heart chamber with cardiac symptoms and is diagnosed by cardiovascular surgeons. We report a case of incidental intravascular lipoleiomyomatosis which was confined to the uterus being diagnosed after a total abdominal hysterectomy by pathology and its management strategy. PMID:25738043

  18. Current concepts in the management of disseminated intravascular coagulation.

    PubMed

    Thachil, Jecko; Toh, Cheng Hock

    2012-04-01

    Disseminated Intravascular Coagulation is a clinicopathological syndrome where widespread intravascular coagulation occurs in response to an inciting process. The pathophysiology for this disorder is complex with an important role for thrombin, the central regulator of the coagulation process. Since the clinical spectrum of DIC is variable due to its dynamic nature, the laboratory diagnosis should ideally be not based on a single marker or an isolated set of results. The treatment should primary focus on the management of the underlying triggering condition with blood products used as resuscitative measures. Newer therapeutic modalities have been recently tried with success although the management of DIC still remains a major challenge.

  19. Incidence of intravascular penetration in transforaminal cervical epidural steroid injections.

    PubMed

    Furman, Michael B; Giovanniello, Michael T; O'Brien, Erin M

    2003-01-01

    STUDY DESIGN A prospective, observational, human, study was conducted. OBJECTIVES To evaluate the incidence of vascular penetration during fluoroscopically guided, contrast-enhanced transforaminal cervical epidural steroid injections, and to determine whether the observation of blood in the needle hub can be used to predict a vascular injection. SUMMARY OF BACKGROUND DATA Incorrectly placed intravascular cervical spinal injections result in medication flow systemically and not to the desired target. A recently published study demonstrates a high incidence of intravascular injections in transforaminal lumbosacral epidural injections. No studies so far have evaluated the incidence of vascular injections in transforaminal cervical epidural steroid injections, nor have they calculated the ability of observed blood in the needle hub to predict a vascular injection in the cervical spine.METHODS The incidence of fluoroscopically confirmed intravascular uptake of contrast was prospectively observed in 337 patients treated with cervical transforaminal epidural steroid injections. The ability of observed blood in the needle hub to predict intravascular injection was also investigated. For each subject, the injection level was chosen on the basis of the clinical scenario including history, physical examination, and review of imaging studies. Some patients had multilevel injections. Using fluoroscopic guidance, the authors placed a 25-gauge needle into the epidural space using a transforaminal approach according to accepted standard technique. Needle tip location was confirmed with biplanar imaging. The presence or absence of blood in the needle hub spontaneously ("flash") and after attempted aspiration by pulling back on the syringe's plunger was documented. Contrast then was injected under real-time fluoroscopy to determine whether the location of the needle tip was intravascular. The results were recorded in a prospective manner indicating the presence or absence of blood

  20. A Prognostic Dilemma of Basal Cell Carcinoma with Intravascular Invasion

    PubMed Central

    Niumsawatt, Vachara; Castley, Andrew

    2016-01-01

    Summary: Basal cell carcinoma is the most common malignancy; however, it very rarely metastasizes. Despite the low mortality caused by this cancer, once it spreads, it has dim prognosis. We report a case of basal cell carcinoma with rare intravascular invasion and review the literature for risk factors and management of metastasis.

  1. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cardiovascular intravascular filter. 870.3375 Section 870.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... side of the heart and the pulmonary circulation. (b) Classification. Class II. The special controls...

  2. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cardiovascular intravascular filter. 870.3375 Section 870.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... side of the heart and the pulmonary circulation. (b) Classification. Class II. The special controls...

  3. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cardiovascular intravascular filter. 870.3375 Section 870.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices §...

  4. 21 CFR 870.3375 - Cardiovascular intravascular filter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cardiovascular intravascular filter. 870.3375 Section 870.3375 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices §...

  5. Intravascular Ultrasound and Virtual Histology of Basilar Artery Atherosclerotic Lesion

    PubMed Central

    López-Rueda, A.; González García, A.; Aguilar Pérez, M.; Gutiérrez Jarrín, R.K.; Mayol Deyá, A.

    2011-01-01

    Summary To our knowledge, this paper presents the first intravascular ultrasound and virtual histology (IVUS-VH) study in the basilar artery. IVUS-VH serves to characterize and determine the extension of the plaque and we also to check stent placement. PMID:22192552

  6. Modern head and neck brachytherapy: from radium towards intensity modulated interventional brachytherapy

    PubMed Central

    2014-01-01

    Intensity modulated brachytherapy (IMBT) is a modern development of classical interventional radiation therapy (brachytherapy), which allows the application of a high radiation dose sparing severe adverse events, thereby further improving the treatment outcome. Classical indications in head and neck (H&N) cancers are the face, the oral cavity, the naso- and oropharynx, the paranasal sinuses including base of skull, incomplete resections on important structures, and palliation. The application type can be curative, adjuvant or perioperative, as a boost to external beam radiation as well as without external beam radiation and with palliative intention. Due to the frequently used perioperative application method (intraoperative implantation of inactive applicators and postoperative performance of radiation), close interdisciplinary cooperation between surgical specialists (ENT-, dento-maxillary-facial-, neuro- and orbital surgeons), as well interventional radiotherapy (brachytherapy) experts are obligatory. Published results encourage the integration of IMBT into H&N therapy, thereby improving the prognosis and quality of life of patients. PMID:25834586

  7. 10 CFR 35.67 - Requirements for possession of sealed sources and brachytherapy sources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... brachytherapy sources. 35.67 Section 35.67 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT... brachytherapy sources. (a) A licensee in possession of any sealed source or brachytherapy source shall follow... brachytherapy sources, except for gamma stereotactic radiosurgery sources, shall conduct a semi-annual...

  8. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  9. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  10. 10 CFR 35.67 - Requirements for possession of sealed sources and brachytherapy sources.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... brachytherapy sources. 35.67 Section 35.67 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT... brachytherapy sources. (a) A licensee in possession of any sealed source or brachytherapy source shall follow... brachytherapy sources, except for gamma stereotactic radiosurgery sources, shall conduct a semi-annual...

  11. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  12. 10 CFR 35.67 - Requirements for possession of sealed sources and brachytherapy sources.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... brachytherapy sources. 35.67 Section 35.67 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT... brachytherapy sources. (a) A licensee in possession of any sealed source or brachytherapy source shall follow... brachytherapy sources, except for gamma stereotactic radiosurgery sources, shall conduct a semi-annual...

  13. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  14. 10 CFR 35.67 - Requirements for possession of sealed sources and brachytherapy sources.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... brachytherapy sources. 35.67 Section 35.67 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT... brachytherapy sources. (a) A licensee in possession of any sealed source or brachytherapy source shall follow... brachytherapy sources, except for gamma stereotactic radiosurgery sources, shall conduct a semi-annual...

  15. 10 CFR 35.67 - Requirements for possession of sealed sources and brachytherapy sources.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... brachytherapy sources. 35.67 Section 35.67 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT... brachytherapy sources. (a) A licensee in possession of any sealed source or brachytherapy source shall follow... brachytherapy sources, except for gamma stereotactic radiosurgery sources, shall conduct a semi-annual...

  16. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  17. The evolution of brachytherapy treatment planning.

    PubMed

    Rivard, Mark J; Venselaar, Jack L M; Beaulieu, Luc

    2009-06-01

    Brachytherapy is a mature treatment modality that has benefited from technological advances. Treatment planning has advanced from simple lookup tables to complex, computer-based dose-calculation algorithms. The current approach is based on the AAPM TG-43 formalism with recent advances in acquiring single-source dose distributions. However, this formalism has clinically relevant limitations for calculating patient dose. Dose-calculation algorithms are being developed based on Monte Carlo methods, collapsed cone, and solving the linear Boltzmann transport equation. In addition to improved dose-calculation tools, planning systems and brachytherapy treatment planning will account for material heterogeneities, scatter conditions, radiobiology, and image guidance. The AAPM, ESTRO, and other professional societies are working to coordinate clinical integration of these advancements. This Vision 20/20 article provides insight into these endeavors.

  18. Rotating-shield brachytherapy for cervical cancer

    NASA Astrophysics Data System (ADS)

    Yang, Wenjun; Kim, Yusung; Wu, Xiaodong; Song, Qi; Liu, Yunlong; Bhatia, Sudershan K.; Sun, Wenqing; Flynn, Ryan T.

    2013-06-01

    In this treatment planning study, the potential benefits of a rotating shield brachytherapy (RSBT) technique based on a partially-shielded electronic brachytherapy source were assessed for treating cervical cancer. Conventional intracavitary brachytherapy (ICBT), intracavitary plus supplementary interstitial (IS+ICBT), and RSBT treatment plans for azimuthal emission angles of 180° (RSBT-180) and 45° (RSBT-45) were generated for five patients. For each patient, high-risk clinical target volume (HR-CTV) equivalent dose in 2 Gy fractions (EQD2) (α/β = 10 Gy) was escalated until bladder, rectum, or sigmoid colon tolerance EQD2 values were reached. External beam radiotherapy dose (1.8 Gy × 25) was accounted for, and brachytherapy was assumed to have been delivered in 5 fractions. IS+ICBT provided a greater HR-CTV D90 (minimum EQD2 to the hottest 90%) than ICBT. D90 was greater for RSBT-45 than IS+ICBT for all five patients, and greater for RSBT-180 than IS+ICBT for two patients. When the RSBT-45/180 plan with the lowest HR-CTV D90 that was greater than the D90 the ICBT or IS+ICBT plan was selected, the average (range) of D90 increases for RSBT over ICBT and IS+ICBT were 16.2 (6.3-27.2)and 8.5 (0.03-20.16) Gy, respectively. The average (range) treatment time increase per fraction of RSBT was 34.56 (3.68-70.41) min over ICBT and 34.59 (3.57-70.13) min over IS+ICBT. RSBT can increase D90 over ICBT and IS+ICBT without compromising organ-at-risk sparing. The D90 and treatment time improvements from RSBT depend on the patient and shield emission angle.

  19. Erectile Function Durability Following Permanent Prostate Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Kurko, Brian S.; Anderson, Richard; Lief, Jonathan H.

    2009-11-01

    Purpose: To evaluate long-term changes in erectile function following prostate brachytherapy. Methods and Materials: This study included 226 patients with prostate cancer and preimplant erectile function assessed by the International Index of Erectile Function-6 (IIEF-6) who underwent brachytherapy in two prospective randomized trials between February 2001 and January 2003. Median follow-up was 6.4 years. Pre- and postbrachytherapy potency was defined as IIEF-6 >= 13 without pharmacologic or mechanical support. The relationship among clinical, treatment, and dosimetric parameters and erectile function was examined. Results: The 7-year actuarial rate of potency preservation was 55.6% with median postimplant IIEF of 22 in potent patients. Potent patients were statistically younger (p = 0.014), had a higher preimplant IIEF (p < 0.001), were less likely to be diabetic (p = 0.002), and were more likely to report nocturnal erections (p = 0.008). Potency preservation in men with baseline IIEF scores of 29-30, 24-28, 18-23, and 13-17 were 75.5% vs. 73.6%, 51.7% vs. 44.8%, 48.0% vs. 40.0%, and 23.5% vs. 23.5% in 2004 vs. 2008. In multivariate Cox regression analysis, preimplant IIEF, hypertension, diabetes, prostate size, and brachytherapy dose to proximal penis strongly predicted for potency preservation. Impact of proximal penile dose was most pronounced for men with IIEF of 18-23 and aged 60-69. A significant minority of men who developed postimplant impotence ultimately regained erectile function. Conclusion: Potency preservation and median IIEF scores following brachytherapy are durable. Thoughtful dose sparing of proximal penile structures and early penile rehabilitation may further improve these results.

  20. Design and optimization of a brachytherapy robot

    NASA Astrophysics Data System (ADS)

    Meltsner, Michael A.

    Trans-rectal ultrasound guided (TRUS) low dose rate (LDR) interstitial brachytherapy has become a popular procedure for the treatment of prostate cancer, the most common type of non-skin cancer among men. The current TRUS technique of LDR implantation may result in less than ideal coverage of the tumor with increased risk of negative response such as rectal toxicity and urinary retention. This technique is limited by the skill of the physician performing the implant, the accuracy of needle localization, and the inherent weaknesses of the procedure itself. The treatment may require 100 or more sources and 25 needles, compounding the inaccuracy of the needle localization procedure. A robot designed for prostate brachytherapy may increase the accuracy of needle placement while minimizing the effect of physician technique in the TRUS procedure. Furthermore, a robot may improve associated toxicities by utilizing angled insertions and freeing implantations from constraints applied by the 0.5 cm-spaced template used in the TRUS method. Within our group, Lin et al. have designed a new type of LDR source. The "directional" source is a seed designed to be partially shielded. Thus, a directional, or anisotropic, source does not emit radiation in all directions. The source can be oriented to irradiate cancerous tissues while sparing normal ones. This type of source necessitates a new, highly accurate method for localization in 6 degrees of freedom. A robot is the best way to accomplish this task accurately. The following presentation of work describes the invention and optimization of a new prostate brachytherapy robot that fulfills these goals. Furthermore, some research has been dedicated to the use of the robot to perform needle insertion tasks (brachytherapy, biopsy, RF ablation, etc.) in nearly any other soft tissue in the body. This can be accomplished with the robot combined with automatic, magnetic tracking.

  1. Brachytherapy needle deflection evaluation and correction

    SciTech Connect

    Wan Gang; Wei Zhouping; Gardi, Lori; Downey, Donal B.; Fenster, Aaron

    2005-04-01

    In prostate brachytherapy, an 18-gauge needle is used to implant radioactive seeds. This thin needle can be deflected from the preplanned trajectory in the prostate, potentially resulting in a suboptimum dose pattern and at times requiring repeated needle insertion to achieve optimal dosimetry. In this paper, we report on the evaluation of brachytherapy needle deflection and bending in test phantoms and two approaches to overcome the problem. First we tested the relationship between needle deflection and insertion depth as well as whether needle bending occurred. Targeting accuracy was tested by inserting a brachytherapy needle to target 16 points in chicken tissue phantoms. By implanting dummy seeds into chicken tissue phantoms under 3D ultrasound guidance, the overall accuracy of seed implantation was determined. We evaluated methods to overcome brachytherapy needle deflection with three different insertion methods: constant orientation, constant rotation, and orientation reversal at half of the insertion depth. Our results showed that needle deflection is linear with needle insertion depth, and that no noticeable bending occurs with needle insertion into the tissue and agar phantoms. A 3D principal component analysis was performed to obtain the population distribution of needle tip and seed position relative to the target positions. Our results showed that with the constant orientation insertion method, the mean needle targeting error was 2.8 mm and the mean seed implantation error was 2.9 mm. Using the constant rotation and orientation reversal at half insertion depth methods, the deflection error was reduced. The mean needle targeting errors were 0.8 and 1.2 mm for the constant rotation and orientation reversal methods, respectively, and the seed implantation errors were 0.9 and 1.5 mm for constant rotation insertion and orientation reversal methods, respectively.

  2. Boost in radiotherapy: external beam sunset, brachytherapy sunrise

    PubMed Central

    2009-01-01

    Radiobiological limitations for dose escalation in external radiotherapy are presented. Biological and clinical concept of brachytherapy boost to increase treatment efficacy is discussed, and different methods are compared. Oncentra Prostate 3D conformal real-time ultrasound-guided brachytherapy is presented as a solution for boost or sole therapy.

  3. 10 CFR 35.2406 - Records of brachytherapy source accountability.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Records of brachytherapy source accountability. 35.2406 Section 35.2406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2406 Records of brachytherapy source accountability. (a) A licensee shall maintain a record of...

  4. 10 CFR 35.2406 - Records of brachytherapy source accountability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Records of brachytherapy source accountability. 35.2406 Section 35.2406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2406 Records of brachytherapy source accountability. (a) A licensee shall maintain a record of...

  5. 10 CFR 35.2406 - Records of brachytherapy source accountability.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Records of brachytherapy source accountability. 35.2406 Section 35.2406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2406 Records of brachytherapy source accountability. (a) A licensee shall maintain a record of...

  6. 10 CFR 35.2406 - Records of brachytherapy source accountability.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Records of brachytherapy source accountability. 35.2406 Section 35.2406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2406 Records of brachytherapy source accountability. (a) A licensee shall maintain a record of...

  7. 10 CFR 35.2406 - Records of brachytherapy source accountability.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Records of brachytherapy source accountability. 35.2406 Section 35.2406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2406 Records of brachytherapy source accountability. (a) A licensee shall maintain a record of...

  8. Ultrasound use in gynecologic brachytherapy: Time to focus the beam.

    PubMed

    van Dyk, Sylvia; Schneider, Michal; Kondalsamy-Chennakesavan, Srinivas; Bernshaw, David; Narayan, Kailash

    2015-01-01

    There is wide disparity in the practice of brachytherapy for cervical cancer around the world. Although select well-resourced centers advocate use of MRI for all insertions, planar X-ray imaging remains the most commonly used imaging modality to assess intracavitary implants, particularly where the burden of cervical cancer is high. Incorporating soft tissue imaging into brachytherapy programs has been shown to improve the technical accuracy of implants, which in turn has led to improved local control and decreased toxicity. These improvements have a positive effect on the quality of life of patients undergoing brachytherapy for cervical cancer. Finding an accessible soft tissue imaging modality is essential to enable these improvements to be available to all patients. A modality that has good soft tissue imaging capabilities, is widely available, portable, and economical, is needed. Ultrasound fulfils these requirements and offers the potential of soft tissue image guidance to a much wider brachytherapy community. Although use of ultrasound is the standard of care in brachytherapy for prostate cancer, it only seems to have limited uptake in gynecologic brachytherapy. This article reviews the role of ultrasound in gynecologic brachytherapy and highlights the potential applications for use in brachytherapy for cervical cancer.

  9. Penile brachytherapy: Results for 49 patients

    SciTech Connect

    Crook, Juanita M. . E-mail: juanita.crook@rmp.uhn.on.ca; Jezioranski, John; Grimard, Laval; Esche, Bernd; Pond, G.

    2005-06-01

    Purpose: To report results for 49 men with squamous cell carcinoma (SCC) of the penis treated with primary penile interstitial brachytherapy at one of two institutions: the Ottawa Regional Cancer Center, Ottawa, and the Princess Margaret Hospital, Toronto, Ontario, Canada. Methods and Materials: From September 1989 to September 2003, 49 men (mean age, 58 years; range, 22-93 years) had brachytherapy for penile SCC. Fifty-one percent of tumors were T1, 33% T2, and 8% T3; 4% were in situ and 4% Tx. Grade was well differentiated in 31%, moderate in 45%, and poor in 2%; grade was unspecified for 20%. One tumor was verrucous. All tumors in Toronto had pulsed dose rate (PDR) brachytherapy (n = 23), whereas those in Ottawa had either Iridium wire (n 22) or seeds (n = 4). Four patients had a single plane implant with a plastic tube technique, and all others had a volume implant with predrilled acrylic templates and two or three parallel planes of needles (median, six needles). Mean needle spacing was 13.5 mm (range, 10-18 mm), mean dose rate was 65 cGy/h (range, 33-160 cGy/h), and mean duration was 98.8 h (range, 36-188 h). Dose rates for PDR brachytherapy were 50-61.2 cGy/h, with no correction in total dose, which was 60 Gy in all cases. Results: Median follow-up was 33.4 months (range, 4-140 months). At 5 years, actuarial overall survival was 78.3% and cause-specific survival 90.0%. Four men died of penile cancer, and 6 died of other causes with no evidence of recurrence. The cumulative incidence rate for never having experienced any type of failure at 5 years was 64.4% and for local failure was 85.3%. All 5 patients with local failure were successfully salvaged by surgery; 2 other men required penectomy for necrosis. The soft tissue necrosis rate was 16% and the urethral stenosis rate 12%. Of 8 men with regional failure, 5 were salvaged by lymph node dissection with or without external radiation. All 4 men with distant failure died of disease. Of 49 men, 42 had an intact

  10. Characterization of coronary atherosclerosis by intravascular imaging modalities.

    PubMed

    Honda, Satoshi; Kataoka, Yu; Kanaya, Tomoaki; Noguchi, Teruo; Ogawa, Hisao; Yasuda, Satoshi

    2016-08-01

    Coronary artery disease (CAD) is highly prevalent in Western countries and is associated with morbidity, mortality, and a significant economic burden. Despite the development of anti-atherosclerotic medical therapies, many patients still continue to suffer from coronary events. This residual risk indicates the need for better risk stratification and additional therapies to achieve more reductions in cardiovascular risk. Recent advances in imaging modalities have contributed to visualizing atherosclerotic plaques and defining lesion characteristics in vivo. This innovation has been applied to refining revascularization procedure, assessment of anti-atherosclerotic drug efficacy and the detection of high-risk plaques. As such, intravascular imaging plays an important role in further improvement of cardiovascular outcomes in patients with CAD. The current article reviews available intravascular imaging modalities with regard to its method, advantage and disadvantage. PMID:27500094

  11. Disseminated intravascular coagulation in term and preterm neonates.

    PubMed

    Veldman, Alex; Fischer, Doris; Nold, Marcel F; Wong, Flora Y

    2010-06-01

    Among critically ill patients, the risk of developing disseminated intravascular coagulation (DIC) is probably highest in neonates. Low plasma reserves in pro- and anticoagulant coagulation factors, intravascular volume contraction after birth, and a high incidence of hypoxia and sepsis in critically ill newborns rapidly lead to a decompensation of the coagulation system in this population. Global coagulation tests and single-factor plasma levels have to be interpreted in the context of age-corrected normal ranges. Platelet consumption and reduced protein C plasma levels have diagnostic value; the latter also has prognostic potential in neonates with DIC and sepsis. Therapeutic success relies heavily on reversal of the underlying condition. Some coagulation-specific therapies have been explored in small studies and case series with varying success and sometimes conflicting results. Therefore, larger controlled trials in this common and serious condition are urgently needed.

  12. Intravascular photoacoustic tomography for characterization of atherosclerotic lipid and inflammation

    NASA Astrophysics Data System (ADS)

    Zhang, Jian; Qin, Huan; Shi, Yujiao; Yang, Sihua; Xing, Da

    2014-09-01

    Photoacoustic imaging is a fast growing imaging technology depending on its high optical resolution of optics while taking the advantage of the high penetration depth of ultrasound. In this paper, we demonstrate the new progress in the photoacoustic imaging. Atherosclerosis is characterized by a progressive build-up of lipid in the arterial wall, which is known as plaque. Histological studies demonstrate that the primary cause of acute cardiovascular events is the rupture of atherosclerotic plaques. Lipid and inflammation within the plaque are related to influence the propensity of plaques to disrupt. Photoacoustic intravascular tomography (IVPAT) holds a great advantage in providing comprehensive morphological and functional information of plaques. Lipid relative concentration maps of atherosclerotic aorta were obtained and compared with histology. Furthermore, by selectively targeting the intravascular inflammatory cytokines, IVPAT is also capable of mapping the inflamed area and determining the degree of inflammation.

  13. Integrated intravascular optical coherence tomography ultrasound imaging system

    NASA Astrophysics Data System (ADS)

    Yin, Jiechen; Yang, Hao-Chung; Li, Xiang; Zhang, Jun; Zhou, Qifa; Hu, Changhong; Shung, K. Kirk; Chen, Zhongping

    2010-01-01

    We report on a dual-modality optical coherence tomography (OCT) ultrasound (US) system for intravascular imaging. To the best of our knowledge, we have developed the first integrated OCT-US probe that combines OCT optical components with an US transducer. The OCT optical components mainly consist of a single-mode fiber, a gradient index lens for light-beam focusing, and a right-angled prism for reflecting light into biological tissue. A 40-MHz piezoelectric transducer (PZT-5H) side-viewing US transducer was fabricated to obtain the US image. These components were integrated into a single probe, enabling both OCT and US imaging at the same time. In vitro OCT and ultrasound images of a rabbit aorta were obtained using this dual-modality imaging system. This study demonstrates the feasibility of an OCT-US system for intravascular imaging, which is expected to have a prominent impact on early detection and characterization of atherosclerosis.

  14. Characterization of coronary atherosclerosis by intravascular imaging modalities

    PubMed Central

    Honda, Satoshi; Kanaya, Tomoaki; Noguchi, Teruo; Ogawa, Hisao; Yasuda, Satoshi

    2016-01-01

    Coronary artery disease (CAD) is highly prevalent in Western countries and is associated with morbidity, mortality, and a significant economic burden. Despite the development of anti-atherosclerotic medical therapies, many patients still continue to suffer from coronary events. This residual risk indicates the need for better risk stratification and additional therapies to achieve more reductions in cardiovascular risk. Recent advances in imaging modalities have contributed to visualizing atherosclerotic plaques and defining lesion characteristics in vivo. This innovation has been applied to refining revascularization procedure, assessment of anti-atherosclerotic drug efficacy and the detection of high-risk plaques. As such, intravascular imaging plays an important role in further improvement of cardiovascular outcomes in patients with CAD. The current article reviews available intravascular imaging modalities with regard to its method, advantage and disadvantage. PMID:27500094

  15. Three-Dimensional Imaging in Gynecologic Brachytherapy: A Survey of the American Brachytherapy Society

    SciTech Connect

    Viswanathan, Akila N.; Erickson, Beth A.

    2010-01-15

    Purpose: To determine current practice patterns with regard to three-dimensional (3D) imaging for gynecologic brachytherapy among American Brachytherapy Society (ABS) members. Methods and Materials: Registered physician members of the ABS received a 19-item survey by e-mail in August 2007. This report excludes physicians not performing brachytherapy for cervical cancer. Results: Of the 256 surveys sent, we report results for 133 respondents who perform one or more implantations per year for locally advanced cervical cancer. Ultrasound aids 56% of physicians with applicator insertion. After insertion, 70% of physicians routinely obtain a computed tomography (CT) scan. The majority (55%) use CT rather than X-ray films (43%) or magnetic resonance imaging (MRI; 2%) for dose specification to the cervix. However, 76% prescribe to Point A alone instead of using a 3D-derived tumor volume (14%), both Point A and tumor volume (7%), or mg/h (3%). Those using 3D imaging routinely contour the bladder and rectum (94%), sigmoid (45%), small bowel (38%), and/or urethra (8%) and calculate normal tissue dose-volume histogram (DVH) analysis parameters including the D2cc (49%), D1cc (36%), D0.1cc (19%), and/or D5cc (19%). Respondents most commonly modify the treatment plan based on International Commission on Radiation Units bladder and/or rectal point dose values (53%) compared with DVH values (45%) or both (2%). Conclusions: More ABS physician members use CT postimplantation imaging than plain films for visualizing the gynecologic brachytherapy apparatus. However, the majority prescribe to Point A rather than using 3D image based dosimetry. Use of 3D image-based treatment planning for gynecologic brachytherapy has the potential for significant growth in the United States.

  16. Central Venous Catheter Intravascular Malpositioning: Causes, Prevention, Diagnosis, and Correction

    PubMed Central

    Roldan, Carlos J.; Paniagua, Linda

    2015-01-01

    Despite the level of skill of the operator and the use of ultrasound guidance, central venous catheter (CVC) placement can result in CVC malpositioning, an unintended placement of the catheter tip in an inadequate vessel. CVC malpositioning is not a complication of central line insertion; however, undiagnosed CVC malpositioning can be associated with significant morbidity and mortality. The objectives of this review were to describe factors associated with intravascular malpositioning of CVCs inserted via the neck and chest and to offer ways of preventing, identifying, and correcting such malpositioning. A literature search of PubMed, Cochrane Library, and MD Consult was performed in June 2014. By searching for “Central line malposition” and then for “Central venous catheters intravascular malposition,” we found 178 articles written in English. Of those, we found that 39 were relevant to our objectives and included them in our review. According to those articles, intravascular CVC malpositioning is associated with the presence of congenital and acquired anatomical variants, catheter insertion in left thoracic venous system, inappropriate bevel orientation upon needle insertion, and patient’s body habitus variants. Although plain chest radiography is the standard imaging modality for confirming catheter tip location, signs and symptoms of CVC malpositioning even in presence of normal or inconclusive conventional radiography findings should prompt the use of additional diagnostic methods to confirm or rule out CVC malpositioning. With very few exceptions, the recommendation in cases of intravascular CVC malpositioning is to remove and relocate the catheter. Knowing the mechanisms of CVC malpositioning and how to prevent, identify, and correct CVC malpositioning could decrease harm to patients with this condition. PMID:26587087

  17. Transponder system for non-invasive measurement of intravascular pressure.

    PubMed

    Schnakenberg, U; Krüger, C; Pfeffer, J G; Mokwa, W; von Bögel, G; Günther, R; Schmitz-Rode, Th

    2002-01-01

    Monitoring of blood pressure and pulse rate offers diagnostical and therapeutical opportunities in hypertension disease and arrhythmia, respectively. This paper presents an intravascular pressure monitoring system consisting of an implantable silicone capsule, which can be placed in an arterial system via a catheter. The capsule contains a pressure sensor and signal conditioning circuits for wireless data and energy transfer using 6.78 MHz transponder technology.

  18. Disseminated intravascular coagulation and hepatocellular necrosis due to clove oil.

    PubMed

    Brown, S A; Biggerstaff, J; Savidge, G F

    1992-10-01

    We describe the case of a 2-year-old child who suffered from disseminated intravascular coagulation (DIC) and hepatocellular necrosis, following ingestion of clove oil. The patient was treated with heparin and fresh frozen plasma, and, following specific haemostasis assays, with appropriate coagulation factor and inhibitor concentrates. The case demonstrates how this approach can be successfully used in the management of DIC with coexisting liver failure. PMID:1450336

  19. Silent intravascular lymphoma initially manifesting as a unilateral adrenal incidentaloma.

    PubMed

    Takahashi, Yoshiko; Iida, Keiji; Hino, Yasuhisa; Ohara, Takeshi; Kurahashi, Toshifumi; Tashiro, Takashi; Chihara, Kazuo

    2012-01-01

    Intravascular large B-cell lymphoma (IVLBCL) is a rare subtype of malignant lymphoma. Although the involvement of adrenal glands in IVLBCL is often observed, primary adrenal IVLBCL is rare. Most reported cases of adrenal IVLBCL showed bilateral lesions resulting in rapidly progressive adrenal failure and poor prognosis. Here, we report a case of slowly progressive primary adrenal IVLBCL manifesting initially with unilateral adrenal incidentaloma. This case is a silent IVLBCL and shows that the enlargement of both adrenal glands can be followed.

  20. Optical device for intravascular low-power laser illumination

    NASA Astrophysics Data System (ADS)

    Grobelny, Andrzej; Palasz, Zbigniew; Beres-Pawlik, Elzbieta M.; Abramski, Krzysztof M.; Derkacz, Arkadiusz; Bialy, Dariusz; Protasiewicz, Marcin

    2003-04-01

    The treatment method presented in this paper is an adjunct to coronary angioplasty. It consists in irradiating a previously dilated artery with laser light which stimulates endothelium proliferation and reduces local inflammation. The influence of 808 nm laser light on the endothelium was studied in vitro. Because of the location of atherosclerotic plaques, illumination of the endothelium poses a problem. To overcome it, we have designed and built a laser set-up for homogeneous intravascular illumination in vivo.

  1. Central Venous Catheter Intravascular Malpositioning: Causes, Prevention, Diagnosis, and Correction.

    PubMed

    Roldan, Carlos J; Paniagua, Linda

    2015-09-01

    Despite the level of skill of the operator and the use of ultrasound guidance, central venous catheter (CVC) placement can result in CVC malpositioning, an unintended placement of the catheter tip in an inadequate vessel. CVC malpositioning is not a complication of central line insertion; however, undiagnosed CVC malpositioning can be associated with significant morbidity and mortality. The objectives of this review were to describe factors associated with intravascular malpositioning of CVCs inserted via the neck and chest and to offer ways of preventing, identifying, and correcting such malpositioning. A literature search of PubMed, Cochrane Library, and MD Consult was performed in June 2014. By searching for "Central line malposition" and then for "Central venous catheters intravascular malposition," we found 178 articles written in English. Of those, we found that 39 were relevant to our objectives and included them in our review. According to those articles, intravascular CVC malpositioning is associated with the presence of congenital and acquired anatomical variants, catheter insertion in left thoracic venous system, inappropriate bevel orientation upon needle insertion, and patient's body habitus variants. Although plain chest radiography is the standard imaging modality for confirming catheter tip location, signs and symptoms of CVC malpositioning even in presence of normal or inconclusive conventional radiography findings should prompt the use of additional diagnostic methods to confirm or rule out CVC malpositioning. With very few exceptions, the recommendation in cases of intravascular CVC malpositioning is to remove and relocate the catheter. Knowing the mechanisms of CVC malpositioning and how to prevent, identify, and correct CVC malpositioning could decrease harm to patients with this condition.

  2. Vascular wall stress during intravascular optical coherence tomography imaging

    NASA Astrophysics Data System (ADS)

    Sun, Cuiru; Yang, Victor

    2015-03-01

    Biomechanical properties of arterial wall is crucial for understanding the changes in the cardiovascular system. Catheters are used during intravascular optical coherence tomography (IVOCT) imaging. The presence of a catheter alters the flow field, pressure distribution and frictional resistance to flow in an artery. In this paper, we first study the transmural stress distribution of the catheterized vessel. COMSOL (COMSOL 4.4) was used to simulate the blood flow induced deformation in a catheterized vessel. Blood is modeled as an incompressible Newtonian fluid. Stress distribution from an three-layer vascular model with an eccentric catheter are simulated, which provides a general idea about the distribution of the displacement and the stress. Optical coherence elastography techniques were then applied to porcine carotid artery samples to look at the deformation status of the vascular wall during saline or water injection. Preliminary simulation results show nonuniform stress distribution in the circumferential direction of the eccentrically catheterized vascular model. Three strain rate methods were tested for intravascular OCE application. The tissue Doppler method has the potential to be further developed to image the vascular wall biomechnical properties in vivo. Although results in this study are not validated quantitatively, the experiments and methods may be valuable for intravascular OCE studies, which may provide important information for cardiovascular disease prevention, diagnosis and treatment.

  3. Integrated intravascular optical coherence tomography (OCT) - ultrasound (US) imaging system

    NASA Astrophysics Data System (ADS)

    Yin, Jiechen; Yang, Hao-Chung; Li, Xiang; Zhou, Qifa; Hu, Changhong; Zhang, Jun; Shung, K. Kirk; Chen, Zhongping

    2010-02-01

    Optical coherence tomography (OCT) and intravascular ultrasound (IVUS) are considered two complementary imaging techniques in the detection and diagnosis of atherosclerosis. OCT permits visualization of micron-scale features of atherosclerosis plaque, and IVUS offers full imaging depth of vessel wall. Under the guidance of IVUS, minimal amount of flushing agent will be needed to obtain OCT imaging of the interested area. We report on a dual-modality optical coherence tomography (OCT) - ultrasound (US) system for intravascular imaging. To the best of our knowledge, we have developed the first integrated OCT-US probe that combines OCT optical components with an ultrasound transducer. The OCT optical components mainly consist of a single mode fiber, a gradient index (GRIN) lens for light beam focusing, and a right-angled prism for reflecting light into biological tissue. A 40MHz PZT-5H side-viewing ultrasound transducer was fabricated to obtain the ultrasound image. These components were integrated into a single probe, enabling both OCT and ultrasound imaging at the same time. In vitro OCT and ultrasound images of a rabbit aorta were obtained using this dual-modality imaging system. This study demonstrates the feasibility of an OCT-US system for intravascular imaging which is expected to have a prominent impact on early detection and characterization of atherosclerosis.

  4. [Current status of intravascular ultrasound in interventional cardiology].

    PubMed

    Kovárník, Tomáš

    2014-12-01

    Although intravascular ultrasound has been used for decades, its common application in catheterization centres during coronary interventions is very rare and merely reaches few percents. The reason is the lack of randomized trials of its use and often few experiences in evaluation of ultrasound findings. Data based on meta-analysis of observational studies clearly demonstrated the positive effect on the most important parameters for the treatment of patients with ischemic heart disease, such as mortality and incidence of myocardial infarction after coronary interventions. Therefore, according to the latest guidelines for myocardial revascularization of the European Society of Cardiology is level of recommendation in category IIa for the use of intravascular ultrasound. IVUS continues to be an important part of new investigation methods which try to better describe coronary atherosclerosis. Particularly, it is the method NIRS (near-infrared spectroscopy) and other new methods of evaluating the composition and mechanical properties of plaque. These facts suggest that IVUS maintains its contribution in time of optical coherence tomography (OCT) and the emphasis put on the functional assessment of coronary stenoses.Key words: coronary atherosclerosis - intravascular ultrasound - percutaneous coronary intervention. PMID:25692833

  5. Renal denervation by intravascular ultrasound: Preliminary in vivo study

    NASA Astrophysics Data System (ADS)

    Sinelnikov, Yegor; McClain, Steve; Zou, Yong; Smith, David; Warnking, Reinhard

    2012-10-01

    Ultrasound denervation has recently become a subject of intense research in connection with the treatment of complex medical conditions including neurological conditions, development of pain management, reproduction of skin sensation, neuropathic pain and spasticity. The objective of this study is to investigate the use of intravascular ultrasound to produce nerve damage in renal sympathetic nerves without significant injury to the renal artery. This technique may potentially be used to treat various medical conditions, such as hypertension. The study was approved by the Institutional Animal Care and Use Committee. Ultrasound was applied to renal nerves of the swine model for histopathological evaluation. Therapeutic ultrasound energy was delivered circumferentially by an intravascular catheter maneuvered into the renal arteries. Fluoroscopic imaging was conducted pre-and post-ultrasound treatment. Animals were recovered and euthanized up to 30 hours post procedure, followed by necropsy and tissue sample collection. Histopathological examination showed evidence of extensive damage to renal nerves, characterized by nuclear pyknosis, hyalinization of stroma and multifocal hemorrhages, with little or no damage to renal arteries. This study demonstrates the feasibility of intravascular ultrasound as a minimally invasive renal denervation technique. Further studies are necessary to evaluate the long-term safety and efficacy of this technique and its related clinical significance.

  6. Caudal epidural anesthesia during intracavitary brachytherapy for cervical cancer.

    PubMed

    Isoyama-Shirakawa, Yuko; Nakamura, Katsumasa; Abe, Madoka; Kunitake, Naonobu; Matsumoto, Keiji; Ohga, Saiji; Sasaki, Tomonari; Uehara, Satoru; Okushima, Kazuhiro; Shioyama, Yoshiyuki; Honda, Hiroshi

    2015-05-01

    It has been suggested that pain control during intracavitary brachytherapy for cervical cancer is insufficient in most hospitals in Japan. Our hospital began using caudal epidural anesthesia during high-dose-rate (HDR) intracavitary brachytherapy in 2011. The purpose of the present study was to retrospectively investigate the effects of caudal epidural anesthesia during HDR intracavitary brachytherapy for cervical cancer patients. Caudal epidural anesthesia for 34 cervical cancer patients was performed during HDR intracavitary brachytherapy between October 2011 and August 2013. We used the patients' self-reported Numeric Rating Scale (NRS) score at the first session of HDR intracavitary brachytherapy as a subjective evaluation of pain. We compared NRS scores of the patients with anesthesia with those of 30 patients who underwent HDR intracavitary brachytherapy without sacral epidural anesthesia at our hospital between May 2010 and August 2011. Caudal epidural anesthesia succeeded in 33 patients (97%), and the NRS score was recorded in 30 patients. The mean NRS score of the anesthesia group was 5.17 ± 2.97, significantly lower than that of the control group's 6.80 ± 2.59 (P = 0.035). The caudal epidural block resulted in no side-effects. Caudal epidural anesthesia is an effective and safe anesthesia option during HDR intracavitary brachytherapy for cervical cancer.

  7. Recent developments and best practice in brachytherapy treatment planning

    PubMed Central

    2014-01-01

    Brachytherapy has evolved over many decades, but more recently, there have been significant changes in the way that brachytherapy is used for different treatment sites. This has been due to the development of new, technologically advanced computer planning systems and treatment delivery techniques. Modern, three-dimensional (3D) imaging modalities have been incorporated into treatment planning methods, allowing full 3D dose distributions to be computed. Treatment techniques involving online planning have emerged, allowing dose distributions to be calculated and updated in real time based on the actual clinical situation. In the case of early stage breast cancer treatment, for example, electronic brachytherapy treatment techniques are being used in which the radiation dose is delivered during the same procedure as the surgery. There have also been significant advances in treatment applicator design, which allow the use of modern 3D imaging techniques for planning, and manufacturers have begun to implement new dose calculation algorithms that will correct for applicator shielding and tissue inhomogeneities. This article aims to review the recent developments and best practice in brachytherapy techniques and treatments. It will look at how imaging developments have been incorporated into current brachytherapy treatment and how these developments have played an integral role in the modern brachytherapy era. The planning requirements for different treatments sites are reviewed as well as the future developments of brachytherapy in radiobiology and treatment planning dose calculation. PMID:24734939

  8. The dosimetry of brachytherapy-induced erectile dysfunction

    SciTech Connect

    Merrick, Gregory S.; Butler, Wayne M

    2003-12-31

    There is emerging evidence that brachytherapy-induced erectile dysfunction (ED) is technique-related and may be minimized by careful attention to source placement. Herein, we review the relationship between radiation doses to the prostate gland/surrounding structures and the development of brachytherapy-induced ED. The permanent prostate brachytherapy literature was reviewed using MEDLINE searches to ensure completeness. Although the site-specific structure associated with brachytherapy-induced ED remains unknown, there is an increasing body of data implicating the proximal penis. With day 0 CT-based dosimetry, the dose to 50% (D{sub 50}) and 25% (D{sub 25}) of the bulb of the penis should be maintained below 40% and 60% mPD, respectively, while the crura D{sub 50} should be maintained below 28% mPD to maximize post-brachytherapy potency. To date, there is no data to suggest that either radiation doses to the neurovascular bundles or choice of isotope is associated with brachytherapy-induced ED, while conflicting data has been reported regarding radiation dose to the prostate and the use of supplemental external beam radiation therapy. Although the etiology of brachytherapy-induced ED is likely multifactorial, the available data supports the proximal penis as an important site-specific structure. Refinements in implant technique, including preplanning and intraoperative seed placement, will result in lower radiation doses to the proximal penis with potential improvement in potency preservation.

  9. Disseminated intravascular large-cell lymphoma with initial presentation mimicking Guillain-Barré syndrome.

    PubMed

    Jiang, Qin Li; Pytel, Peter; Rowin, Julie

    2010-07-01

    We report a patient with intravascular large B-cell lymphoma who initially presented with acute ascending weakness and sensory changes. Electrodiagnostic testing and cerebral spinal fluid (CSF) studies were initially suggestive of a demyelinating polyneuropathy. Further clinical evaluation and testing were consistent with mononeuropathy multiplex. Autopsy revealed disseminated intravascular large-cell lymphoma. Intravascular large-cell lymphoma should be considered in the differential diagnosis of a rapidly evolving neuropathy associated with other organ involvement.

  10. Multihelix rotating shield brachytherapy for cervical cancer

    SciTech Connect

    Dadkhah, Hossein; Kim, Yusung; Flynn, Ryan T.; Wu, Xiaodong

    2015-11-15

    Purpose: To present a novel brachytherapy technique, called multihelix rotating shield brachytherapy (H-RSBT), for the precise angular and linear positioning of a partial shield in a curved applicator. H-RSBT mechanically enables the dose delivery using only linear translational motion of the radiation source/shield combination. The previously proposed approach of serial rotating shield brachytherapy (S-RSBT), in which the partial shield is rotated to several angular positions at each source dwell position [W. Yang et al., “Rotating-shield brachytherapy for cervical cancer,” Phys. Med. Biol. 58, 3931–3941 (2013)], is mechanically challenging to implement in a curved applicator, and H-RSBT is proposed as a feasible solution. Methods: A Henschke-type applicator, designed for an electronic brachytherapy source (Xoft Axxent™) and a 0.5 mm thick tungsten partial shield with 180° or 45° azimuthal emission angles and 116° asymmetric zenith angle, is proposed. The interior wall of the applicator contains six evenly spaced helical keyways that rigidly define the emission direction of the partial radiation shield as a function of depth in the applicator. The shield contains three uniformly distributed protruding keys on its exterior wall and is attached to the source such that it rotates freely, thus longitudinal translational motion of the source is transferred to rotational motion of the shield. S-RSBT and H-RSBT treatment plans with 180° and 45° azimuthal emission angles were generated for five cervical cancer patients with a diverse range of high-risk target volume (HR-CTV) shapes and applicator positions. For each patient, the total number of emission angles was held nearly constant for S-RSBT and H-RSBT by using dwell positions separated by 5 and 1.7 mm, respectively, and emission directions separated by 22.5° and 60°, respectively. Treatment delivery time and tumor coverage (D{sub 90} of HR-CTV) were the two metrics used as the basis for evaluation and

  11. Design, construction, and validation of a rotary multifunctional intravascular diagnostic catheter combining multispectral fluorescence lifetime imaging and intravascular ultrasound.

    PubMed

    Bec, Julien; Xie, Hongtao; Yankelevich, Diego R; Zhou, Feifei; Sun, Yang; Ghata, Narugopal; Aldredge, Ralph; Marcu, Laura

    2012-10-01

    We report the development and validation of an intravascular rotary catheter for bimodal interrogation of arterial pathologies. This is based on a point-spectroscopy scanning time-resolved fluorescence spectroscopy technique enabling reconstruction of fluorescence lifetime images (FLIm) and providing information on arterial intima composition and intravascular ultrasound (IVUS) providing information on arterial wall morphology. The catheter design allows for independent rotation of the ultrasonic and optical channels within an 8 Fr outer diameter catheter sheath and integrates a low volume flushing channel for blood removal in the optical pathways. In the current configuration, the two channels consist of (a) a standard 3 Fr IVUS catheter with single element transducer (40 MHz) and (b) a side-viewing fiber optic (400 μm core). Experiments conducted in tissue phantoms showed the ability of the catheter to operate in an intraluminal setting and to generate coregistered FLIm and IVUS in one pull-back scan. Current results demonstrate the feasibility of the catheter for simultaneous bimodal interrogation of arterial lumen and for generation of robust fluorescence lifetime data under IVUS guidance. These results facilitate further development of a FLIm-IVUS technique for intravascular diagnosis of atherosclerotic cardiovascular diseases including vulnerable plaques.

  12. Design, construction, and validation of a rotary multifunctional intravascular diagnostic catheter combining multispectral fluorescence lifetime imaging and intravascular ultrasound

    NASA Astrophysics Data System (ADS)

    Bec, Julien; Xie, Hongtao; Yankelevich, Diego R.; Zhou, Feifei; Sun, Yang; Ghata, Narugopal; Aldredge, Ralph; Marcu, Laura

    2012-10-01

    We report the development and validation of an intravascular rotary catheter for bimodal interrogation of arterial pathologies. This is based on a point-spectroscopy scanning time-resolved fluorescence spectroscopy technique enabling reconstruction of fluorescence lifetime images (FLIm) and providing information on arterial intima composition and intravascular ultrasound (IVUS) providing information on arterial wall morphology. The catheter design allows for independent rotation of the ultrasonic and optical channels within an 8 Fr outer diameter catheter sheath and integrates a low volume flushing channel for blood removal in the optical pathways. In the current configuration, the two channels consist of (a) a standard 3 Fr IVUS catheter with single element transducer (40 MHz) and (b) a side-viewing fiber optic (400 μm core). Experiments conducted in tissue phantoms showed the ability of the catheter to operate in an intraluminal setting and to generate coregistered FLIm and IVUS in one pull-back scan. Current results demonstrate the feasibility of the catheter for simultaneous bimodal interrogation of arterial lumen and for generation of robust fluorescence lifetime data under IVUS guidance. These results facilitate further development of a FLIm-IVUS technique for intravascular diagnosis of atherosclerotic cardiovascular diseases including vulnerable plaques.

  13. Brachytherapy in the treatment of cervical cancer: a review

    PubMed Central

    Banerjee, Robyn; Kamrava, Mitchell

    2014-01-01

    Dramatic advances have been made in brachytherapy for cervical cancer. Radiation treatment planning has evolved from two-dimensional to three-dimensional, incorporating magnetic resonance imaging and/or computed tomography into the treatment paradigm. This allows for better delineation and coverage of the tumor, as well as improved avoidance of surrounding organs. Consequently, advanced brachytherapy can achieve very high rates of local control with a reduction in morbidity, compared with historic approaches. This review provides an overview of state-of-the-art gynecologic brachytherapy, with a focus on recent advances and their implications for women with cervical cancer. PMID:24920937

  14. Dosimetric characterization and output verification for conical brachytherapy surface applicators. Part I. Electronic brachytherapy source

    SciTech Connect

    Fulkerson, Regina K. Micka, John A.; DeWerd, Larry A.

    2014-02-15

    Purpose: Historically, treatment of malignant surface lesions has been achieved with linear accelerator based electron beams or superficial x-ray beams. Recent developments in the field of brachytherapy now allow for the treatment of surface lesions with specialized conical applicators placed directly on the lesion. Applicators are available for use with high dose rate (HDR){sup 192}Ir sources, as well as electronic brachytherapy sources. Part I of this paper will discuss the applicators used with electronic brachytherapy sources; Part II will discuss those used with HDR {sup 192}Ir sources. Although the use of these applicators has gained in popularity, the dosimetric characteristics including depth dose and surface dose distributions have not been independently verified. Additionally, there is no recognized method of output verification for quality assurance procedures with applicators like these. Existing dosimetry protocols available from the AAPM bookend the cross-over characteristics of a traditional brachytherapy source (as described by Task Group 43) being implemented as a low-energy superficial x-ray beam (as described by Task Group 61) as observed with the surface applicators of interest. Methods: This work aims to create a cohesive method of output verification that can be used to determine the dose at the treatment surface as part of a quality assurance/commissioning process for surface applicators used with HDR electronic brachytherapy sources (Part I) and{sup 192}Ir sources (Part II). Air-kerma rate measurements for the electronic brachytherapy sources were completed with an Attix Free-Air Chamber, as well as several models of small-volume ionization chambers to obtain an air-kerma rate at the treatment surface for each applicator. Correction factors were calculated using MCNP5 and EGSnrc Monte Carlo codes in order to determine an applicator-specific absorbed dose to water at the treatment surface from the measured air-kerma rate. Additionally

  15. Improving photoacoustic imaging contrast of brachytherapy seeds

    NASA Astrophysics Data System (ADS)

    Pan, Leo; Baghani, Ali; Rohling, Robert; Abolmaesumi, Purang; Salcudean, Septimiu; Tang, Shuo

    2013-03-01

    Prostate brachytherapy is a form of radiotherapy for treating prostate cancer where the radiation sources are seeds inserted into the prostate. Accurate localization of seeds during prostate brachytherapy is essential to the success of intraoperative treatment planning. The current standard modality used in intraoperative seeds localization is transrectal ultrasound. Transrectal ultrasound, however, suffers in image quality due to several factors such speckle, shadowing, and off-axis seed orientation. Photoacoustic imaging, based on the photoacoustic phenomenon, is an emerging imaging modality. The contrast generating mechanism in photoacoustic imaging is optical absorption that is fundamentally different from conventional B-mode ultrasound which depicts changes in acoustic impedance. A photoacoustic imaging system is developed using a commercial ultrasound system. To improve imaging contrast and depth penetration, absorption enhancing coating is applied to the seeds. In comparison to bare seeds, approximately 18.5 dB increase in signal-to-noise ratio as well as a doubling of imaging depth are achieved. Our results demonstrate that the coating of the seeds can further improve the discernibility of the seeds.

  16. Coregistered photoacoustic-ultrasound imaging applied to brachytherapy

    NASA Astrophysics Data System (ADS)

    Harrison, Tyler; Zemp, Roger J.

    2011-08-01

    Brachytherapy is a form of radiation therapy commonly used in the treatment of prostate cancer wherein sustained radiation doses can be precisely targeted to the tumor area by the implantation of small radioactive seeds around the treatment area. Ultrasound is a popular imaging mode for seed implantation, but the seeds are difficult to distinguish from the tissue structure. In this work, we demonstrate the feasibility of photoacoustic imaging for identifying brachytherapy seeds in a tissue phantom, comparing the received intensity to endogenous contrast. We have found that photoacoustic imaging at 1064 nm can identify brachytherapy seeds uniquely at laser penetration depths of 5 cm in biological tissue at the ANSI limit for human exposure with a contrast-to-noise ratio of 26.5 dB. Our realtime combined photoacoustic-ultrasound imaging approach may be suitable for brachytherapy seed placement and post-placement verification, potentially allowing for realtime dosimetry assessment during implantation.

  17. Patient release criteria for low dose rate brachytherapy implants.

    PubMed

    Boyce, Dale E; Sheetz, Michael A

    2013-04-01

    A lack of consensus regarding a model governing the release of patients following sealed source brachytherapy has led to a set of patient release policies that vary from institution to institution. The U.S. Nuclear Regulatory Commission has issued regulatory guidance on patient release in NUREG 1556, Volume 9, Rev. 2, Appendix U, which allows calculation of release limits following implant brachytherapy. While the formalism presented in NUREG is meaningful for the calculation of release limits in the context of relatively high energy gamma emitters, it does not estimate accurately the effective dose equivalent for the common low dose rate brachytherapy sources Cs, I, and Pd. NUREG 1556 states that patient release may be based on patient-specific calculations as long as the calculation is documented. This work is intended to provide a format for patient-specific calculations to be used for the consideration of patients' release following the implantation of certain low dose rate brachytherapy isotopes. PMID:23439145

  18. Image-Based Brachytherapy for the Treatment of Cervical Cancer

    SciTech Connect

    Harkenrider, Matthew M. Alite, Fiori; Silva, Scott R.; Small, William

    2015-07-15

    Cervical cancer is a disease that requires considerable multidisciplinary coordination of care and labor in order to maximize tumor control and survival while minimizing treatment-related toxicity. As with external beam radiation therapy, the use of advanced imaging and 3-dimensional treatment planning has generated a paradigm shift in the delivery of brachytherapy for the treatment of cervical cancer. The use of image-based brachytherapy, most commonly with magnetic resonance imaging (MRI), requires additional attention and effort by the treating physician to prescribe dose to the proper volume and account for adjacent organs at risk. This represents a dramatic change from the classic Manchester approach of orthogonal radiographic images and prescribing dose to point A. We reviewed the history and currently evolving data and recommendations for the clinical use of image-based brachytherapy with an emphasis on MRI-based brachytherapy.

  19. Bothrops jararaca envenomation: Pathogenesis of hemostatic disturbances and intravascular hemolysis

    PubMed Central

    Senise, Luana V; Yamashita, Karine M

    2015-01-01

    To attain fully functional biological activity, vitamin-K dependent coagulation factors (VKDCF) are γ-carboxylated prior to secretion from liver. Warfarin impairs the γ-carboxylation, and consequently their physiological function. Bothrops jararaca snake venom (BjV) contains several activators of blood coagulation, especially procoagulant enzymes (prothrombin and factor X activators) and thrombin-like enzymes. In order to clarify the relative contribution of prothrombin and factor X activators to the hemostatic disturbances occurring during experimental B. jararaca envenomation, warfarin was used to deplete VKDCF, prior to BjV administration. Male Wistar rats were pretreated with saline (Sal) or warfarin (War) and inoculated subsequently with BjV or saline, thus forming four groups: Sal + Sal (negative control), Sal + BjV (positive control), War + Sal (warfarinization control), and War + BjV. Three hours after inoculation, prothrombin and factor X levels fell 40% and 50%, respectively; levels of both factors decreased more than 97% in the War + Sal and War + BjV groups. Platelet counts dropped 93% and 76% in Sal + BjV and War + BjV, respectively, and plasma fibrinogen levels decreased 86% exclusively in Sal + BjV. After 6 and 24 h, platelet counts and fibrinogen levels increased progressively. A dramatic augmentation in plasma hemoglobin levels and the presence of schizocytes and microcytes in the Sal + BjV group indicated the development of intravascular hemolysis, which was prevented by warfarin pretreatment. Our findings show that intravascular thrombin generation has the foremost role in the pathogenesis of coagulopathy and intravascular hemolysis, but not in the development of thrombocytopenia, in B. jararaca envenomation in rats; in addition, fibrinogenases (metalloproteinases) may contribute to coagulopathy more than thrombin-like enzymes. PMID:26080462

  20. The evolution of computerized treatment planning for brachytherapy: American contributions

    PubMed Central

    Rivard, Mark J.

    2014-01-01

    Purpose To outline the evolution of computerized brachytherapy treatment planning in the United States through a review of technological developments and clinical practice refinements. Material and methods A literature review was performed and interviews were conducted with six participants in the development of computerized treatment planning for brachytherapy. Results Computerized brachytherapy treatment planning software was initially developed in the Physics Departments of New York's Memorial Hospital (by Nelson, Meurk and Balter), and Houston's M. D. Anderson Hospital (by Stovall and Shalek). These public-domain programs could be used by institutions with adequate computational resources; other clinics had access to them via Memorial's and Anderson's teletype-based computational services. Commercial brachytherapy treatment planning programs designed to run on smaller computers (Prowess, ROCS, MMS), were developed in the late 1980s and early 1990s. These systems brought interactive dosimetry into the clinic and surgical theatre. Conclusions Brachytherapy treatment planning has evolved from systems of rigid implant rules to individualized pre- and intra-operative treatment plans, and post-operative dosimetric assessments. Brachytherapy dose distributions were initially calculated on public domain programs on large regionally located computers. With the progression of computer miniaturization and increase in processor speeds, proprietary software was commercially developed for microcomputers that offered increased functionality and integration with clinical practice. PMID:25097560

  1. 21 CFR 880.5970 - Percutaneous, implanted, long-term intravascular catheter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...: “Guidance on Premarket Notification Submission for Short-Term and Long-Term Intravascular Catheters.” ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Percutaneous, implanted, long-term intravascular... and Personal Use Therapeutic Devices § 880.5970 Percutaneous, implanted, long-term...

  2. 21 CFR 880.5970 - Percutaneous, implanted, long-term intravascular catheter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...: “Guidance on Premarket Notification Submission for Short-Term and Long-Term Intravascular Catheters.” ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Percutaneous, implanted, long-term intravascular... and Personal Use Therapeutic Devices § 880.5970 Percutaneous, implanted, long-term...

  3. 21 CFR 880.5970 - Percutaneous, implanted, long-term intravascular catheter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...: “Guidance on Premarket Notification Submission for Short-Term and Long-Term Intravascular Catheters.” ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Percutaneous, implanted, long-term intravascular... and Personal Use Therapeutic Devices § 880.5970 Percutaneous, implanted, long-term...

  4. [Incidence of biological intravascular coagulation in legal induced abortions].

    PubMed

    Boudaoud, S; Eurin, B; Drouet, L; Alhomme, P; Dreyfus, R; Serfaty, D

    1986-01-01

    A prospective study was designed to evaluate coagulation abnormalities induced by early abortion (before ten weeks of pregnancy). Fifty-two women underwent suction abortion, under diazepam-fentanyl anaesthesia with spontaneous ventilation; they were screened for coagulation parameters before and after surgery. Eight tests were carried out: prothrombin time, activated partial thromboplastin time (APTT), thrombin time platelet count, fibrinogen levels, fibrin split products, fibrin soluble complexes and euglobulin lysis time. Results were consistent with activation. Consequences were limited and one general test (APTT) was not significantly modified. Suction abortion, even performed in early pregnancy, exposed to biological disseminated intravascular coagulation with a general risk of venous thrombosis.

  5. Disseminated Intravascular Coagulation after Surgery for Facial Injury

    PubMed Central

    Tachibana, Hirohiko; Ishikawa, Shigeo; Yusa, Kazuyuki; Kitabatake, Kenichirou; Iino, Mitsuyoshi

    2016-01-01

    A case of disseminated intravascular coagulation (DIC) presenting after surgery for facial trauma associated with multiple facial bone fractures is described. With regard to the oral and maxillofacial region, DIC has been described in the literature following head trauma, infection, and metastatic disease. Until now, only 5 reports have described DIC after surgery for facial injury. DIC secondary to facial injury is thus rare. The patient in this case was young and had no medical history. Preoperative hemorrhage or postoperative septicemia may thus induce DIC. PMID:27313913

  6. Application of tissue characterization in intravascular ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Mullen, William L.; Fitzgerald, Peter J.; Yock, Paul G.

    1994-05-01

    Current intravascular ultrasound imaging technology is able to determine the extent and distribution of pathologic processes within the vessel wall, but is not highly sensitive in discriminating between certain types of tissue. `Tissue characterization' refers to a set of computer-based techniques that utilize features of the ultrasound signal beyond basic amplitude to help define the composition of the tissue of interest. This technique involves quantitative analysis of the ultrasound signals reflected from tissue before these signals pass through the processing steps in the ultrasound instrument.

  7. Venous gas embolism - Time course of residual pulmonary intravascular bubbles

    NASA Technical Reports Server (NTRS)

    Butler, B. D.; Luehr, S.; Katz, J.

    1989-01-01

    A study was carried out to determine the time course of residual pulmonary intravascular bubbles after embolization with known amounts of venous air, using an N2O challenge technique. Attention was also given to the length of time that the venous gas emboli remained as discrete bubbles in the lungs with 100 percent oxygen ventilation. The data indicate that venous gas emboli can remain in the pulmonary vasculature as discrete bubbles for periods lasting up to 43 + or - 10.8 min in dogs ventilated with oxygen and nitrogen. With 100 percent oxygen ventilation, these values are reduced significantly to 19 + or - 2.5 min.

  8. Intravascular filarial parasites elaborate cyclooxygenase-derived eicosanoids

    PubMed Central

    1990-01-01

    The nematode parasites that cause human lymphatic filariasis survive for long periods in their vascular habitats despite continual exposure to host cells. Since prostanoids formed from arachidonic acid can modulate interactions among platelets, leukocytes, and endothelial cells, we examined whether intravascular nematode parasites can elaborate prostanoids. Microfilariae of Brugia malayi utilize exogenous and endogenous arachidonic acid to generate and release two predominant prostanoids, prostacyclin and prostaglandin E2. Filarial metabolism of host fatty acids to form these vasodilatory, antiaggregatory, and immunomodulatory eicosanoids provides a means by which these helminthic parasites may influence host immune and other cellular responses. PMID:2117642

  9. Removal of Chronic Intravascular Blood Clots using Liquid Plasma

    NASA Astrophysics Data System (ADS)

    Jung, Jae-Chul; Choi, Myeong; Koo, Il; Yu, Zengqi; Collins, George

    2011-10-01

    An electrical embolectomy device for removing chronic intravascular blood clots using liquid plasma under saline environment was demonstrated. We employed a proxy experimental blood clot model of deep vein thrombosis (DVT) and actual equine blood clot. Thermal damage to contiguous tissue and the collagen denaturing via the plasma irradiation were investigated by histological analysis using birefringence of the tissue and verified by FT-IR spectroscopic study, respectively, which showed the high removal rate up to 2 mm per minute at room temperature and small thermal damage less than 200 μm.

  10. Predictors of Metastatic Disease After Prostate Brachytherapy

    SciTech Connect

    Forsythe, Kevin; Burri, Ryan; Stone, Nelson; Stock, Richard G.

    2012-06-01

    Purpose: To identify predictors of metastatic disease after brachytherapy treatment for prostate cancer. Methods and Materials: All patients who received either brachytherapy alone (implant) or brachytherapy in combination with external beam radiation therapy for treatment of localized prostate cancer at The Mount Sinai Hospital between June 1990 and March 2007 with a minimum follow-up of 2 years were included. Univariate and multivariable analyses were performed on the following variables: risk group, Gleason score (GS), clinical T stage, pretreatment prostate-specific antigen level, post-treatment prostate-specific antigen doubling time (PSA-DT), treatment type (implant vs. implant plus external beam radiation therapy), treatment era, total biological effective dose, use of androgen deprivation therapy, age at diagnosis, and race. PSA-DT was analyzed in the following ordinate groups: 0 to 90 days, 91 to 180 days, 180 to 360 days, and greater than 360 days. Results: We included 1,887 patients in this study. Metastases developed in 47 of these patients. The 10-year freedom from distant metastasis (FFDM) rate for the entire population was 95.1%. Median follow-up was 6 years (range, 2-15 years). The only two significant predictors of metastatic disease by multivariable analyses were GS and PSA-DT (p < 0.001 for both variables). Estimated 10-year FFDM rates for GS of 6 or less, GS of 7, and GS of 8 or greater were 97.9%, 94.3%, and 76.1%, respectively (p < 0.001). Estimated FFDM rates for PSA-DT of 0 to 90 days, 91 to 180 days, 181 to 360 days, and greater than 360 days were 17.5%, 67.9%, 74%, and 94.8%, respectively (p < 0.001). Estimated 10-year FFDM rates for the low-, intermediate-, and high-risk groups were 98.6%, 96.2%, and 86.7%, respectively. A demographic shift to patients presenting with higher-grade disease in more recent years was observed. Conclusions: GS and post-treatment PSA-DT are both statistically significant independent predictors of metastatic

  11. Dose characterization in the near-source region for two high dose rate brachytherapy sources.

    PubMed

    Wang, Ruqing; Li, X Allen

    2002-08-01

    High dose rate (HDR) 192Ir sources are currently used in intravascular brachytherapy (IVB) for the peripheral arterial system. This poses a demand on evaluating accurate dose parameters in the near-source region for such sources. The purpose of this work is to calculate the dose parameters for the old VariSource HDR 192Ir source and the new microSelectron HDR 192Ir source, using Monte Carlo electron and photon transport simulation. The two-dimensional (2D) dose rate distributions and the air kerma strengths for the two HDR sources were calculated by EGSnrc and EGS4 Monte Carlo codes. Based on these data, the dose parameters proposed in the AAPM TG-60 protocol were derived. The dose rate constants obtained are 13.119+/-0.028 cGy h(-1) U(-1) for the old VariSource source, and 22.751+/-0.031 cGy h(-1) U(-1) for the new microSelectron source at the reference point (r0 = 2 mm, theta = pi/2). The 2D dose rate distributions, the radial dose functions, and the anisotropy functions presented for the two sources cover radial distances ranging from 0.5 to 10 mm. In the near-source region on the transverse plane, the dose effects of the charged particle nonequilibrium and the beta-particle dose contribution were studied. It is found that at radial distances ranging from 0.5 to 2 mm, these effects increase the calculated dose rates by up to 29% for the old VariSource source, and by up to 12% for the new microSelectron source, which, in turn, change values of the radial dose function and the anisotropy function. The present dose parameters, which account for the charged particle nonequilibrium and the beta particle contribution, may be used for accurate IVB dose calculation. PMID:12201413

  12. A dynamic dosimetry system for prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Kuo, Nathanael; Dehghan, Ehsan; Deguet, Anton; Song, Danny Y.; Prince, Jerry L.; Lee, Junghoon

    2013-03-01

    The lack of dynamic dosimetry tools for permanent prostate brachytherapy causes otherwise avoidable problems in prostate cancer patient care. The goal of this work is to satisfy this need in a readily adoptable manner. Using the ubiquitous ultrasound scanner and mobile non-isocentric C-arm, we show that dynamic dosimetry is now possible with only the addition of an arbitrarily configured marker-based fiducial. Not only is the system easily configured from accessible hardware, but it is also simple and convenient, requiring little training from technicians. Furthermore, the proposed system is built upon robust algorithms of seed segmentation, fiducial detection, seed reconstruction, and image registration. All individual steps of the pipeline have been thoroughly tested, and the system as a whole has been validated on a study of 25 patients. The system has shown excellent results of accurately computing dose, and does so with minimal manual intervention, therefore showing promise for widespread adoption of dynamic dosimetry.

  13. Paddle-based rotating-shield brachytherapy

    SciTech Connect

    Liu, Yunlong; Xu, Weiyu; Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Buatti, John M.; Dadkhah, Hossein; Wu, Xiaodong

    2015-10-15

    Purpose: The authors present a novel paddle-based rotating-shield brachytherapy (P-RSBT) method, whose radiation-attenuating shields are formed with a multileaf collimator (MLC), consisting of retractable paddles, to achieve intensity modulation in high-dose-rate brachytherapy. Methods: Five cervical cancer patients using an intrauterine tandem applicator were considered to assess the potential benefit of the P-RSBT method. The P-RSBT source used was a 50 kV electronic brachytherapy source (Xoft Axxent™). The paddles can be retracted independently to form multiple emission windows around the source for radiation delivery. The MLC was assumed to be rotatable. P-RSBT treatment plans were generated using the asymmetric dose–volume optimization with smoothness control method [Liu et al., Med. Phys. 41(11), 111709 (11pp.) (2014)] with a delivery time constraint, different paddle sizes, and different rotation strides. The number of treatment fractions (fx) was assumed to be five. As brachytherapy is delivered as a boost for cervical cancer, the dose distribution for each case includes the dose from external beam radiotherapy as well, which is 45 Gy in 25 fx. The high-risk clinical target volume (HR-CTV) doses were escalated until the minimum dose to the hottest 2 cm{sup 3} (D{sub 2cm{sup 3}}) of either the rectum, sigmoid colon, or bladder reached their tolerance doses of 75, 75, and 90 Gy{sub 3}, respectively, expressed as equivalent doses in 2 Gy fractions (EQD2 with α/β = 3 Gy). Results: P-RSBT outperformed the two other RSBT delivery techniques, single-shield RSBT (S-RSBT) and dynamic-shield RSBT (D-RSBT), with a properly selected paddle size. If the paddle size was angled at 60°, the average D{sub 90} increases for the delivery plans by P-RSBT on the five cases, compared to S-RSBT, were 2.2, 8.3, 12.6, 11.9, and 9.1 Gy{sub 10}, respectively, with delivery times of 10, 15, 20, 25, and 30 min/fx. The increases in HR-CTV D{sub 90}, compared to D-RSBT, were 16

  14. Automatic Brachytherapy Seed Placement Under MRI Guidance

    PubMed Central

    Patriciu, Alexandru; Petrisor, Doru; Muntener, Michael; Mazilu, Dumitru; Schär, Michael; Stoianovici, Dan

    2011-01-01

    The paper presents a robotic method of performing low dose rate prostate brachytherapy under magnetic resonance imaging (MRI) guidance. The design and operation of a fully automated MR compatible seed injector is presented. This is used with the MrBot robot for transperineal percutaneous prostate access. A new image-registration marker and algorithms are also presented. The system is integrated and tested with a 3T MRI scanner. Tests compare three different registration methods, assess the precision of performing automated seed deployment, and use the seeds to assess the accuracy of needle targeting under image guidance. Under the ideal conditions of the in vitro experiments, results show outstanding image-guided needle and seed placement accuracy. PMID:17694871

  15. An overview of interstitial brachytherapy and hyperthermia

    SciTech Connect

    Brandt, B.B.; Harney, J.

    1989-11-01

    Interstitial thermoradiotherapy, an experimental cancer treatment that combines interstitial radiation implants (brachytherapy) and interstitial hyperthermia, is in the early stages of investigation. In accordance with the procedure used in a current national trial protocol, a 60-minute hyperthermia treatment is administered after catheters are placed into the tumor area while the patient is under general anesthesia. This is immediately followed by loading of radioactive Iridium-192 seeds into the catheters for a defined period of time. Once the prescribed radiation dose is delivered, the radioactive sources are removed and a second, 60-minute hyperthermia treatment is administered. Clinical trials with hyperthermia in combination with radiation have increased in recent years. Nurses caring for these patients need to become more knowledgeable about this investigational therapy. This paper provides an overview of the biologic rationale for this therapy, as well as a description of the delivery method and clinical application. Specific related nursing interventions are defined in a nursing protocol.23 references.

  16. 10 CFR 35.2432 - Records of calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Records of calibration measurements of brachytherapy... Records § 35.2432 Records of calibration measurements of brachytherapy sources. (a) A licensee shall maintain a record of the calibrations of brachytherapy sources required by § 35.432 for 3 years after...

  17. 10 CFR 35.2432 - Records of calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Records of calibration measurements of brachytherapy... Records § 35.2432 Records of calibration measurements of brachytherapy sources. (a) A licensee shall maintain a record of the calibrations of brachytherapy sources required by § 35.432 for 3 years after...

  18. 10 CFR 35.2432 - Records of calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Records of calibration measurements of brachytherapy... Records § 35.2432 Records of calibration measurements of brachytherapy sources. (a) A licensee shall maintain a record of the calibrations of brachytherapy sources required by § 35.432 for 3 years after...

  19. 10 CFR 35.2432 - Records of calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Records of calibration measurements of brachytherapy... Records § 35.2432 Records of calibration measurements of brachytherapy sources. (a) A licensee shall maintain a record of the calibrations of brachytherapy sources required by § 35.432 for 3 years after...

  20. 10 CFR 35.2432 - Records of calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Records of calibration measurements of brachytherapy... Records § 35.2432 Records of calibration measurements of brachytherapy sources. (a) A licensee shall maintain a record of the calibrations of brachytherapy sources required by § 35.432 for 3 years after...

  1. Intravascular photoacoustic imaging at 35 and 80 MHz

    PubMed Central

    Li, Xiang; Wei, Wei; Shung, K. Kirk

    2012-01-01

    Abstract. The catheter-based intravascular photoacoustic (IVPA) imaging for diagnosing atherosclerosis, which can provide optical absorption contrast of the arterial wall besides acoustic scattering contrast from the conventional intravascular ultrasound (IVUS) imaging, has been intensively researched recently. The resolution of IVPA is determined by the frequency bandwidth of an ultrasonic transducer. Higher resolution can be achieved by increasing the transducer’s working frequency and bandwidth. We introduce IVPA imaging at 35 and 80 MHz by using newly designed integrated IVUS/IVPA probes. This is the first time IVPA has been achieved as high as 80 MHz. Six-micrometer tungsten wires were imaged to evaluate the probes’ spatial resolutions and beam patterns. Healthy rabbit aorta was imaged in vitro. Imaging results show that IVPA has superior contrast over IVUS in identifying the arterial wall, and IVPA at 80 MHz demonstrates extraordinary resolution (35 μm) compared to 35 MHz. PMID:23224004

  2. Thyroid Storm Complicated by Bicytopenia and Disseminated Intravascular Coagulation

    PubMed Central

    Tokushima, Yoshinori; Sakanishi, Yuta; Nagae, Kou; Tokushima, Midori; Tago, Masaki; Tomonaga, Motosuke; Yoshioka, Tsuneaki; Hyakutake, Masaki; Sugioka, Takashi; Yamashita, Shu-ichi

    2014-01-01

    Patient: Male, 23 Final Diagnosis: Thyroid storm Symptoms: Delirium • diarrhea • fever • hypertension • hyperventilation • tachycardia • weight loss Medication: — Clinical Procedure: — Specialty: Endocrinology and Metabolic Objective: Unusual clinical course Background: The clinical presentation of thyroid storm includes fever, tachycardia, hypertension, and neurological abnormalities. It is a serious condition with a high mortality rate. Furthermore, some other complications affect the clinical course of thyroid storm. Although it is reported that prognosis is poor when thyroid storm is complicated by disseminated intravascular coagulation syndrome (DIC) and leukopenia, reports of such cases are rare. Case Report: A 23-year-old man presented with delirium, high pyrexia, diarrhea, and weight loss of 18 kg over 2 months. According to the criteria of Burch and Wartofsky, he was diagnosed with thyroid storm on the basis of his symptom-complex and laboratory data that confirmed the presence of hyperthyroidism. Investigations also found leukopenia, thrombocytopenia, and disseminated intravascular coagulation, all of which are very rare complications of thyroid storm. We successfully treated him with combined therapy including anti-thyroid medication, despite leukopenia. Conclusions: Early diagnosis and treatment are essential in ensuring a good outcome for patients with this rare combination of medical problems. PMID:25072662

  3. [Disseminated intravascular coagulation. Case series and literature review].

    PubMed

    Del Carpio-Orantes, Luis; García-Ortiz, Jorge José

    2014-01-01

    INTRODUCCIÓN: la coagulación intravascular diseminada es una entidad caracteriza por activación de la cascada de la coagulación y fibrinólisis endógena, que puede provocar la muerte. Nuestros objetivos fueron identificar la incidencia de coagulación intravascular diseminada, sus agentes etiológicos y la correlación entre la puntuación de la escala Apache II y la propuesta por la Sociedad Internacional de Trombosis y Hemostasia para el diagnóstico de esta entidad. MÉTODOS: estudio retrospectivo, observacional y descriptivo de pacientes atendidos en una unidad de cuidados intensivos en un periodo de 17 meses. Se analizó etiología, edad, sexo, conteo de plaquetas, coagulograma, niveles de fibrinógeno sérico y cuantificación del dímero D. Se calculó la puntuación de la escala propuesta por la Sociedad Internacional de Trombosis y Hemostasia y de la escala APACHE II.

  4. A short contemporary history of disseminated intravascular coagulation.

    PubMed

    Levi, Marcel; van der Poll, Tom

    2014-11-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic intravascular activation of coagulation, leading to a widespread deposition of fibrin in the circulation. There is ample experimental and pathological evidence that the fibrin deposition contributes to multiple organ failure. The massive and ongoing activation of coagulation may result in depletion of platelets and coagulation factors, which may cause bleeding (consumption coagulopathy). The syndrome of DIC is well known in the medical literature for centuries, although a more precise description of the underlying mechanisms had to await the 20th century. Initial ideas on a role of the contact activation system as the primary trigger for the systemic activation of coagulation as well as a presumed hyperfibrinolytic response in DIC have been found to be misconceptions. Experimental and clinical evidence now indicate that the initiation of coagulation in DIC is caused by tissue factor expression, which in combination with downregulated physiological anticoagulant pathways and impaired fibrinolysis leads to widespread fibrin deposition. In addition, an extensive bidirectional interaction between coagulation and inflammation may further contribute to the pathogenesis of DIC.

  5. Fatal Cryocrystalglobulinemia With Intravascular and Renal Tubular Crystalline Deposits.

    PubMed

    DeLyria, Paul A; Avedschmidt, Sarah E; Yamada, Chisa; Farkash, Evan A

    2016-05-01

    Cryocrystalglobulinemia is a rare variant of cryoglobulinemia in which monoclonal immunoglobulins self-assemble into crystalline arrays. We report a case of a 53-year-old man who presented with systemic thrombotic microangiopathy causing multiorgan failure, including decreased kidney, lung, and gastrointestinal function; skin necrosis; and mental status changes. Skin and kidney biopsy specimens showed intravascular thrombi, along with intravascular, intratubular, and periglomerular crystalline deposits. Typical morphologic features of cryoglobulinemia, such as a leukocytoclastic vasculitis and pseudothrombi, were absent. Spindled crystals precipitated in the cryoglobulin assay, and immunofixation showed them to be composed of monoclonal immunoglobulin G κ light chains. Ultrastructural analysis demonstrated deposits to have an array-like substructure. The patient was successfully treated with a combination of plasmapheresis, steroids, and bortezomib, but experienced a relapse and died 12 months after his initial diagnosis. Cryocrystalglobulinemia causes significant morbidity and mortality and should be classified as a monoclonal gammopathy of renal significance when it occurs in patients not meeting diagnostic criteria for multiple myeloma. PMID:26775022

  6. Development of catheters for combined intravascular ultrasound and photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Karpiouk, Andrei B.; Wang, Bo; Emelianov, Stanislav Y.

    2009-02-01

    Coronary atherosclerosis is a complex disease accompanied by the development of plaques in the arterial wall. Since the vulnerability of the plaques depends on their composition, the appropriate treatment of the arteriosclerosis requires a reliable characterization of the plaques' geometry and content. The intravascular ultrasound (IVUS) imaging is capable of providing structural details of the plaques as well as some functional information. In turn, more functional information about the same plaques can be obtained from intravascular photoacoustic (IVPA) images since the optical properties of the plaque's components differ from that of their environment. The combined IVUS/IVPA imaging is capable of simultaneously detecting and differentiating the plaques, thus determining their vulnerability. The potential of combined IVUS/IVPA imaging has already been demonstrated in phantoms and ex-vivo experiments. However, for in-vivo or clinical imaging, an integrated IVUS/IVPA catheter is required. In this paper, we introduce two prototypes of integrated IVUS/IVPA catheters for in-vivo imaging based on a commercially available single-element IVUS imaging catheter. The light delivery systems are developed using multimode optical fibers with custom-designed distal tips. Both prototypes were tested and compared using an arterial mimicking phantom. The advantages and limitations of both designs are discussed. Overall, the results of our studies suggest that both designs of integrated IVUS/IVPA catheter have a potential for in-vivo IVPA/IVUS imaging of atherosclerotic plaques.

  7. High speed intravascular photoacoustic imaging of atherosclerotic arteries (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Piao, Zhonglie; Ma, Teng; Qu, Yueqiao; Li, Jiawen; Yu, Mingyue; He, Youmin; Shung, K. Kirk; Zhou, Qifa; Kim, Chang-Seok; Chen, Zhongping

    2016-02-01

    Cardiovascular disease is the leading cause of death in the industrialized nations. Accurate quantification of both the morphology and composition of lipid-rich vulnerable atherosclerotic plaque are essential for early detection and optimal treatment in clinics. In previous works, intravascular photoacoustic (IVPA) imaging for detection of lipid-rich plaque within coronary artery walls has been demonstrated in ex vivo, but the imaging speed is still limited. In order to increase the imaging speed, a high repetition rate laser is needed. In this work, we present a high speed integrated IVPA/US imaging system with a 500 Hz optical parametric oscillator laser at 1725 nm. A miniature catheter with 1.0 mm outer diameter was designed with a 200 μm multimode fiber and an ultrasound transducer with 45 MHz center frequency. The fiber was polished at 38 degree and enclosed in a glass capillary for total internal reflection. An optical/electrical rotary junction and pull-back mechanism was applied for rotating and linearly scanning the catheter to obtain three-dimensional imaging. Atherosclerotic rabbit abdominal aorta was imaged as two frame/second at 1725 nm. Furthermore, by wide tuning range of the laser wavelength from 1680 nm to 1770 nm, spectroscopic photoacoustic analysis of lipid-mimicking phantom and an human atherosclerotic artery was performed ex vivo. The results demonstrated that the developed IVPA/US imaging system is capable for high speed intravascular imaging for plaque detection.

  8. Dominant neurologic symptomatology in intravascular large B-cell lymphoma.

    PubMed

    Kubisova, K; Martanovic, P; Sisovsky, V; Tomleinova, Z; Steno, A; Janega, P; Rychly, B; Babal, P

    2016-01-01

    Intravascular large B-cell lymphoma (IVLBCL) is a rare variant of extranodal large B-cell lymphoma and it is characterized by selective intravascular proliferation of malignant cells. Typical features of the disease include aggressive behavior, rapid and frequently fatal course. Clinical picture is non-specific and heterogeneous, depending on the affected organ. It is not uncommon that this unique type of lymphoma is diagnosed post mortem. Herein, we report two cases of IVLBCL with neurologic symptomatology. In our clinical study patient 1 was an 80-year-old male with mixed paraparesis of lower extremities and difficulties with sphincter control. Patient 2 (56-year-old male) had vision malfunction, mental status changes and defect in phatic and motor functions. In both cases definite diagnosis was established by histological examination of necroptic material. We propose to include IVLBCL in differential diagnostic considerations in patients presenting with gradually impairing neurological status and spinal cord damage of unknown etiology (Fig. 2, Ref. 9). PMID:27546361

  9. Dual-element needle transducer for intravascular ultrasound imaging

    PubMed Central

    Yoon, Sangpil; Kim, Min Gon; Williams, Jay A.; Yoon, Changhan; Kang, Bong Jin; Cabrera-Munoz, Nestor; Shung, K. Kirk; Kim, Hyung Ham

    2015-01-01

    Abstract. A dual-element needle transducer for intravascular ultrasound imaging has been developed. A low-frequency element and a high-frequency element were integrated into one device to obtain images which conveyed both low- and high-frequency information from a single scan. The low-frequency element with a center frequency of 48 MHz was fabricated from the single crystal form of lead magnesium niobate-lead titanate solid solution with two matching layers (MLs) and the high frequency element with a center frequency of 152 MHz was fabricated from lithium niobate with one ML. The measured axial and lateral resolutions were 27 and 122  μm, respectively, for the low-frequency element, and 14 and 40  μm, respectively, for the high-frequency element. The performance of the dual-element needle transducer was validated by imaging a tissue-mimicking phantom with lesion-mimicking area, and ex vivo rabbit aortas in water and rabbit whole blood. The results suggest that a low-frequency element effectively provides depth resolved images of the whole vessel and its adjacent tissue, and a high-frequency element visualizes detailed structure near the surface of the lumen wall in the presence of blood within the lumen. The advantages of a dual-element approach for intravascular imaging are also discussed. PMID:26158118

  10. Focused intravascular ultrasonic probe using dimpled transducer elements.

    PubMed

    Chen, Y; Qiu, W B; Lam, K H; Liu, B Q; Jiang, X P; Zheng, H R; Luo, H S; Chan, H L W; Dai, J Y

    2015-02-01

    High-frequency focused intravascular ultrasonic probes were fabricated in this study using dimple technique based on PMN-PT single crystal and lead-free KNN-KBT-Mn ceramic. The center frequency, bandwidth, and insertion loss of the PMN-PT transducer were 34 MHz, 75%, and 22.9 dB, respectively. For the lead-free probe, the center frequency, bandwidth, and insertion loss were found to be 40 MHz, 72%, and 28.8 dB, respectively. The ultrasonic images of wire phantom and vessels with good resolution were obtained to evaluate the transducer performance. The -6 dB axial and lateral resolutions of the PMN-PT probe were determined to be 58 μm and 131 μm, respectively. For the lead-free probe, the axial and lateral resolutions were found to be 44 μm and 125 μm, respectively. These results suggest that the mechanical dimpling technique has good potential in preparing focused transducers for intravascular ultrasound applications. PMID:25108608

  11. The syndrome of pneumococcemia, disseminated intravascular coagulation and asplenia.

    PubMed Central

    Kingston, M E; MacKenzie, C R

    1979-01-01

    A 58-year-old man who survived an episode of fulminant pneumococcal septicemia with disseminated intravascular coagulation had undergone splenectomy 23 years previously. In the literature there are 25 reported cases of fulminant septicemia and disseminated intravascular coagulation associated with asplenia in adults (excluding cases in which corticosteroid or immunosuppressive therapy was given). The pneumococcus was responsible for all of these cases as well. The mortality in this series was more than 90%, and death occurred within 24 hours of presentation at hospital in almost 70% of the fatal cases and was associated with high-density bacteremia and adrenal hemorrhage. Gram-staining of the buffy coat of the peripheral blood or the exudate from purpuric skin lesions was carried out in only 6 of the 26 cases but yielded positive results in all but 1. It is concluded that a diagnosis of septicemia in asplenic adults can be established within a short time of presentation on the basis of statistical probability and the results of Gram-staining of the peripheral blood and exudate from the skin lesions. Prevention appears to be the cornerstone of management because of the variable interval from splenectomy to the onset of the syndrome and the high mortality. Images FIG. 1 PMID:38002

  12. Incorporating seed orientation in brachytherapy implant reconstruction

    NASA Astrophysics Data System (ADS)

    Zhou, Yu; Jain, Ameet K.; Chirikjian, Gregory S.; Fichtinger, Gabor

    2006-03-01

    Intra-operative quality assurance and dosimetry optimization in prostate brachytherapy critically depends on the ability of discerning the locations of implanted seeds. Various methods exist for seed matching and reconstruction from multiple segmented C-arm images. Unfortunately, using three or more images makes the problem NP-hard, i.e. no polynomial-time algorithm can provably compute the complete matching. Typically, a statistical analysis of performance is considered sufficient. Hence it is of utmost importance to exploit all the available information in order to minimize the matching and reconstruction errors. Current algorithms use only the information about seed centers, disregarding the information about the orientations and length of seeds. While the latter has little dosimetric impact, it can positively contribute to improving seed matching rate and 3D implant reconstruction accuracy. It can also become critical information when hidden and spuriously segmented seeds need to be matched, where reliable and generic methods are not yet available. Expecting orientation information to be useful in reconstructing large and dense implants, we have developed a method which incorporates seed orientation information into our previously proposed reconstruction algorithm (MARSHAL). Simulation study shows that under normal segmentation errors, when considering seed orientations, implants of 80 to 140 seeds with the density of 2.0- 3.0 seeds/cc give an average matching rate >97% using three-image matching. It is higher than the matching rate of about 96% when considering only seed positions. This means that the information of seed orientations appears to be a valuable additive to fluoroscopy-based brachytherapy implant reconstruction.

  13. A Novel Device for Intravaginal Electronic Brachytherapy

    SciTech Connect

    Schneider, Frank Fuchs, Holger; Lorenz, Friedlieb; Steil, Volker; Ziglio, Francesco; Kraus-Tiefenbacher, Uta; Lohr, Frank; Wenz, Frederik

    2009-07-15

    Purpose: Postoperative intravaginal brachytherapy for endometrial carcinoma is usually performed with {sup 192}Ir high-dose rate (HDR) afterloading. A potential alternative is treatment with a broadband 50kV X-ray point source, the advantage being its low energy and the consequential steep dose gradient. The aim of this study was to create and evaluate a homogeneous cylindrical energy deposition around a newly designed vaginal applicator. Methods and Materials: To create constant isodose layers along the cylindrical plastic vaginal applicator, the source (INTRABEAM system) was moved in steps of 17-19.5 mm outward from the tip of the applicator. Irradiation for a predetermined time was performed at each position. The axial shift was established by a stepping mechanism that was mounted on a table support. The total dose/dose distribution was determined using film dosimetry (Gafchromic EBT) in a 'solid water' phantom. The films were evaluated with Mathematica 5.2 and OmniPro-I'mRT 1.6. The results (dose D0/D5/D10 in 0/5/10 mm tissue depth) were compared with an {sup 192}Ir HDR afterloading plan for multiple sampling points around the applicator. Results: Three different dose distributions with lengths of 3.9-7.3 cm were created. The irradiation time based on the delivery of 5/7 Gy to a 5 mm tissue depth was 19/26 min to 27/38 min. D0/D5/D10 was 150%/100%/67% for electronic brachytherapy and 140%/100%/74% for the afterloading technique. The deviation for repeated measurements in the phantom was <7%. Conclusions: It is possible to create a homogeneous cylindrical dose distribution, similar to {sup 192}Ir HDR afterloading, through the superimposition of multiple spherical dose distributions by stepping a kilovolt point source.

  14. Intravascular ultrasound imaging of peripheral arteries as an adjunct to balloon angioplasty and atherectomy.

    PubMed

    Korogi, Y; Hirai, T; Takahashi, M

    1996-01-01

    This article reviews many of the applications of intravascular ultrasound (US) imaging for peripheral arterial diseases. In vitro studies demonstrate an excellent correlation between ultrasound measurements of lumen and plaque cross-sectional area compared with histologic sections. In vivo clinical studies reveal the enhanced diagnostic capabilities of this technology compared with angiography. Intravascular US imaging can provide valuable information on the degree, eccentricity, and histologic type of stenosis before intervention, and on the morphological changes in the arterial wall and the extent of excision after intervention. Intravascular US may also serve as a superior index for gauging the diameter of balloon, stent, laser probe, and/or atherectomy catheter appropriate for a proposed intervention. Significant new insights into the mechanisms of balloon angioplasty and atherectomy have been established by intravascular US findings. Intravascular US imaging has been shown to be a more accurate method than angiography for determining the cross-sectional area of the arterial lumen, and for assessing severity of stenosis. Quantitative assessment of the luminal cross-sectional area after the balloon dilatation should be more accurate than angiography as intimal tears or dissections produced by the dilatation may not be accurately evaluated with angiography. At the present time, intravascular US is still a controversial imaging technique. Outcome studies are currently being organized to assess the clinical value and cost effectiveness of intravascular ultrasound in the context of these interventional procedures. PMID:8653738

  15. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    PubMed Central

    Smith, Grace L; Huo, Jinhai; Giordano, Sharon H.; Hunt, Kelly K.; Buchholz, Thomas A; Smith, Benjamin D

    2015-01-01

    Background Breast brachytherapy after lumpectomy is controversial in younger patients, as effectiveness is unclear and selection criteria are debated. Methods Using MarketScan® healthcare claims data, we identified 45,884 invasive breast cancer patients (ages 18–64), treated from 2003–2010 with lumpectomy, followed by brachytherapy (n=3,134) or whole breast irradiation (WBI) (n=42,750). We stratified patients into risk groups, based on age (Age<50 vs. Age≥50) and endocrine therapy status (Endocrine− vs. Endocrine+). “Endocrine+” patients filled an endocrine therapy prescription within 1 year after lumpectomy. Pathologic hormone receptor status was not available in this dataset. In brachytherapy vs. WBI patients, utilization trends and 5-year subsequent mastectomy risks were compared. Stratified, adjusted subsequent mastectomy risks were calculated using proportional hazards regression. Results Brachytherapy utilization increased from 2003 to 2010: In patients Age<50, from 0.6% to 4.9%; patients Age≥50 from 2.2% to 11.3%; Endocrine− patients, 1.3% to 9.4%; Endocrine+ patients, 1.9% to 9.7%. Age influenced treatment selection more than endocrine status: 17% of brachytherapy patients were Age<50 vs. 32% of WBI patients (P<0.001); while 41% of brachytherapy patients were Endocrine- vs. 44% of WBI patients (P=0.003). Highest absolute 5-year subsequent mastectomy risks occurred in Endocrine−/Age<50 patients (24.4% after brachytherapy vs. 9.0% after WBI (Hazard ratio[HR]=2.18, 1.37–3.47); intermediate risks in Endocrine−/Age≥50 patients (8.6% vs. 4.9%; HR=1.76, 1.26–2.46); and lowest risks in Endocrine+ patients of any age: Endocrine+/Age<50 (5.5% vs. 4.5%; HR=1.18, 0.61–2.31); Endocrine+/Age≥50 (4.2% vs. 2.4%; HR=1.71, 1.16–2.51). Conclusion In this younger cohort, endocrine status was a valuable discriminatory factor predicting subsequent mastectomy risk after brachytherapy vs. WBI and therefore may be useful for selecting appropriate

  16. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    SciTech Connect

    Smith, Grace L.; Huo, Jinhai; Giordano, Sharon H.; Hunt, Kelly K.; Buchholz, Thomas A.; Smith, Benjamin D.

    2015-09-01

    Purpose: To directly compare (1) radiation treatment utilization patterns; (2) risks of subsequent mastectomy; and (3) costs of radiation treatment in patients treated with brachytherapy versus whole-breast irradiation (WBI), in a national, contemporary cohort of women with incident breast cancer, aged 64 years and younger. Methods and Materials: Using MarketScan health care claims data, we identified 45,884 invasive breast cancer patients (aged 18-64 years), treated from 2003 to 2010 with lumpectomy, followed by brachytherapy (n=3134) or whole-breast irradiation (n=42,750). We stratified patients into risk groups according to age (Age<50 vs Age≥50) and endocrine therapy status (Endocrine− vs Endocrine+). “Endocrine+” patients filled an endocrine therapy prescription within 1 year after lumpectomy. Pathologic hormone receptor status was not available in this dataset. In brachytherapy versus WBI patients, utilization trends and 5-year subsequent mastectomy risks were compared. Stratified, adjusted subsequent mastectomy risks were calculated using proportional hazards regression. Results: Brachytherapy utilization increased from 2003 to 2010: in patients Age<50, from 0.6% to 4.9%; patients Age≥50 from 2.2% to 11.3%; Endocrine− patients, 1.3% to 9.4%; Endocrine+ patients, 1.9% to 9.7%. Age influenced treatment selection more than endocrine status: 17% of brachytherapy patients were Age<50 versus 32% of WBI patients (P<.001); whereas 41% of brachytherapy patients were Endocrine–versus 44% of WBI patients (P=.003). Highest absolute 5-year subsequent mastectomy risks occurred in Endocrine−/Age<50 patients (24.4% after brachytherapy vs 9.0% after WBI (hazard ratio [HR] 2.18, 95% confidence interval [CI] 1.37-3.47); intermediate risks in Endocrine−/Age≥50 patients (8.6% vs 4.9%; HR 1.76, 95% CI 1.26-2.46); and lowest risks in Endocrine+ patients of any age: Endocrine+/Age<50 (5.5% vs 4.5%; HR 1.18, 95% CI 0.61-2.31); Endocrine+/Age≥50 (4.2% vs 2

  17. Prostate brachytherapy in patients with median lobe hyperplasia.

    PubMed

    Wallner, K; Smathers, S; Sutlief, S; Corman, J; Ellis, W

    2000-06-20

    Our aim was to document the technical and clinical course of prostate brachytherapy patients with radiographic evidence of median lobe hyperplasia (MLH). Eight patients with MLH were identified during our routine brachytherapy practice, representing 9% of the 87 brachytherapy patients treated during a 6-month period. No effort was made to avoid brachytherapy in patients noted to have MLH on diagnostic work-up. Cystoscopic evaluation was not routinely performed. Postimplant axial computed tomographic (CT) images of the prostate were obtained at 0.5 cm intervals. Preimplant urinary obstructive symptoms were quantified by the criteria of the American Urologic Association (AUA). Each patient was contacted during the writing of this report to update postimplant morbidity information. There was no apparent association between the degree of MLH and preimplant prostate volume or AUA score. Intraoperatively, we were able to visualize MLH by transrectal ultrasound and did not notice any particular difficulty placing sources in the MLH tissue or migration of sources out of the tissue. The prescription isodose covered from 81% to 99% of the postimplant CT-defined target volume, achieving adequate dose to the median lobe tissue in all patients. Two of the eight patients developed acute, postimplant urinary retention. The first patient required intermittent self-catheterization for 3 months and then resumed spontaneous urination. MLH does not appear to be a strong contraindication to prostate brachytherapy, and prophylactic resection of hypertrophic tissue in such patients is probably not warranted. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 152-156 (2000). PMID:10900427

  18. Intravascular ultrasound and optical coherence tomography imaging of coronary atherosclerosis.

    PubMed

    Costopoulos, Charis; Brown, Adam J; Teng, Zhongzhao; Hoole, Stephen P; West, Nick E J; Samady, Habib; Bennett, Martin R

    2016-01-01

    Invasive imaging modalities, in particular intravascular ultrasound (IVUS) and optical coherence tomography (OCT), have become established tools for the in vivo study of coronary atherosclerosis. Their use in clinical studies has confirmed histopathological observations that certain important plaque features, such as thin fibrous caps and large lipid cores, are associated with plaque rupture, the precipitating event for the majority of myocardial infarctions. Serial imaging studies have also successfully been used for the evaluation of potential disease modifying pharmacological agents. Recent prospective IVUS studies have confirmed specific baseline imaging features associated with subsequent adverse clinical outcomes, although absolute event rates were too low for clinical utility. Development of hybrid IVUS-OCT imaging or integration of novel techniques, including near-infrared spectroscopy, plaque structural and endothelial shear stress, have great potential to improve our current ability to identify and stratify atheromatous plaques at risk of rupture.

  19. Acute renal failure and intravascular hemolysis following henna ingestion.

    PubMed

    Qurashi, Hala E A; Qumqumji, Abbas A A; Zacharia, Yasir

    2013-05-01

    The powder of henna plant (Lawsonia inermis Linn.) is extensively used as a decorative skin paint for nail coloring and as a hair dye. Most reports of henna toxicity have been attributed to adding a synthetic dye para-phenylenediamine (PPD). PPD is marketed as black henna added to natural henna to accentuate the dark color and shorten the application time. PPD toxicity is well known and extensively reported in medical literature. We report a case of a young Saudi male who presented with characteristic features of acute renal failure and intravascular hemolysis following ingestion of henna mixture. Management of PPD poisoning is only supportive and helpful only if instituted early. Diagnosis requires a high degree of clinical suspicion, as the clinical features are quite distinctive. PMID:23640630

  20. Mathematical Modeling of Intravascular Blood Coagulation under Wall Shear Stress.

    PubMed

    Rukhlenko, Oleksii S; Dudchenko, Olga A; Zlobina, Ksenia E; Guria, Georgy Th

    2015-01-01

    Increased shear stress such as observed at local stenosis may cause drastic changes in the permeability of the vessel wall to procoagulants and thus initiate intravascular blood coagulation. In this paper we suggest a mathematical model to investigate how shear stress-induced permeability influences the thrombogenic potential of atherosclerotic plaques. Numerical analysis of the model reveals the existence of two hydrodynamic thresholds for activation of blood coagulation in the system and unveils typical scenarios of thrombus formation. The dependence of blood coagulation development on the intensity of blood flow, as well as on geometrical parameters of atherosclerotic plaque is described. Relevant parametric diagrams are drawn. The results suggest a previously unrecognized role of relatively small plaques (resulting in less than 50% of the lumen area reduction) in atherothrombosis and have important implications for the existing stenting guidelines.

  1. Basic studies on intravascular low-intensity laser therapy

    NASA Astrophysics Data System (ADS)

    Liu, Timon Cheng-Yi; Duan, Rui; Wang, Shuang-Xi; Liu, Jiang; Cui, Li-Ping; Jin, Hua; Liu, Song-Hao

    2006-09-01

    Intravascular low intensity laser therapy (ILILT) was originally put forward in USA in 1982, but popularized in Russia in 1980s and in China in 1990s, respectively. A randomized placebo-controlled study has shown ILILT clinical efficacy in patients suffering from rheumatoid arthritis. As Chinese therapeutic applications of ILILT were the most widely in the world, its basic research, such as intracellular signal transduction research, blood research in vitro, animal blood research in vivo, human blood research in vivo and traditional Chinese medicine research, was also very progressive in China. Its basic studies will be reviewed in terms of the biological information model of photobiomodulation in this paper. ILILT might work in view of its basic studies, but the further randomized placebo-controlled trial and the further safety research should be done.

  2. [Traumatic abruption of the placenta with disseminated intravascular coagulation].

    PubMed

    Benz, R; Malär, A-U; Benz-Wörner, J; Scherer, M; Hodel, M; Gähler, A; Haberthür, C; Konrad, C

    2012-10-01

    Trauma in pregnancy is infrequent and a systematic primary strategy constitutes a real challenge for the interdisciplinary team. With a high fetal mortality rate and a substantial maternal mortality rate traumatic placental abruption is a severe emergency which every anesthetist should be aware of. After hemodynamic stabilization of the mother and control of the viability of the fetus the therapy of traumatic placental abruption consists mostly of an immediate caesarean section. Coagulopathy by depletion of coagulation factors as well as disseminated intravascular coagulation (DIC) have to be expected and consequently a massive blood loss must be anticipated. Thrombelastography provides assistance for fast differential diagnosis and goal-directed treatment of the disturbed sections of the coagulation cascade.

  3. Thrombocytopenia and thrombosis in disseminated intravascular coagulation (DIC).

    PubMed

    Kitchens, Craig S

    2009-01-01

    Disseminated intravascular coagulation (DIC) is the physiologic result of pathologic overstimulation of the coagulation system. Despite multiple triggers, a myriad of laboratory abnormalities, and a clinical presentation ranging from gross hemostatic failure to life-threatening thrombosis, or even both simultaneously, a simplified clinical approach augmented by a few readily available tests allows prompt identification of the process and elucidation of treatment opportunities. Platelet counts in DIC may be low, especially in acute sepsis-associated DIC, yet increased in malignancy-associated chronic DIC. Thrombotic risk is not a function of the platelet count, and thrombocytopenia does not protect the patient from thrombosis. The stratification of both thrombotic risk and hemorrhagic risk will be addressed.

  4. Disseminated intravascular coagulation in obstetric and gynecologic disorders.

    PubMed

    Montagnana, Martina; Franchi, Massimo; Danese, Elisa; Gotsch, Francesca; Guidi, Gian Cesare

    2010-06-01

    Disseminated intravascular coagulation (DIC) is a syndrome characterized by a massive, widespread, and ongoing activation of the coagulation system, secondary to a variety of clinical conditions. Many obstetric complications, such as abruptio placentae, amniotic fluid embolism, endotoxin sepsis, retained dead fetus, post-hemorrhagic shock, hydatidiform mole, and gynecologic malignancies, might trigger DIC. In these gynecologic and obstetric settings, DIC is usually associated with high mortality and morbidity rates. No single laboratory test is sensitive or specific enough to diagnose DIC definitively, but it can be diagnosed by using a combination of multiple clinical and laboratory tests that reflect the pathophysiology of the syndrome. At present, the therapeutical approach to pregnancy- and gynecologic-related DIC comprises the specific and aggressive treatment of the underlying disease, eventually followed by a supportive blood product replacement therapy and restoration of physiological anticoagulant pathways. This article reviews the etiopathogenesis, clinical manifestations, laboratory diagnosis, and therapy of pregnancy- and gynecologic-related DIC.

  5. Potential diagnostic markers for disseminated intravascular coagulation of sepsis.

    PubMed

    Iba, Toshiaki; Ito, Takashi; Maruyama, Ikuro; Jilma, Bernd; Brenner, Thorsten; Müller, Marcella C A; Juffermans, Nicole P; Thachil, Jecko

    2016-03-01

    Disseminated intravascular coagulation (DIC) is an acquired thrombo-haemorrhagic disorder which arises in clinical scenarios like sepsis, trauma and malignancies. The clinic-laboratory diagnosis of DIC is made in a patient who develops the combination of laboratory abnormalities in the appropriate clinical scenario. The most common laboratory parameters in this setting have been the clotting profile, platelet count, serum fibrinogen and fibrin degradation markers. These tests had the advantage that they could be performed easily and in most laboratories. However, with the better understanding of the pathophysiology of DIC, in recent years, more specific tests have been suggested to be useful in this setting. The newer tests can also prove to be useful in prognostication in DIC. In addition, they may provide assistance in the selection and monitoring of patients diagnosed with DIC.

  6. Adaptive Estimation of Intravascular Shear Rate Based on Parameter Optimization

    NASA Astrophysics Data System (ADS)

    Nitta, Naotaka; Takeda, Naoto

    2008-05-01

    The relationships between the intravascular wall shear stress, controlled by flow dynamics, and the progress of arteriosclerosis plaque have been clarified by various studies. Since the shear stress is determined by the viscosity coefficient and shear rate, both factors must be estimated accurately. In this paper, an adaptive method for improving the accuracy of quantitative shear rate estimation was investigated. First, the parameter dependence of the estimated shear rate was investigated in terms of the differential window width and the number of averaged velocity profiles based on simulation and experimental data, and then the shear rate calculation was optimized. The optimized result revealed that the proposed adaptive method of shear rate estimation was effective for improving the accuracy of shear rate calculation.

  7. Advanced Congestive Heart Failure Associated With Disseminated Intravascular Coagulopathy.

    PubMed

    Sarcon, Annahita; Liu, Xiaoli; Ton, David; Haywood, James; Hitchcock, Todd

    2015-01-01

    Background. Disseminated intravascular coagulopathy (DIC) is a complication of an underlying disease and not a primary illness. It is most commonly associated with sepsis, trauma, obstetrical complications, and malignancies. There are very few cases in the literature illustrating the association between DIC and congestive heart failure. Findings. In this report, we present a case of severe congestive heart failure, leading to biventricular thrombi and subsequently DIC. Conclusion. We suggest that the association between congestive heart failure and DIC is an underrecognized one. Congestive heart failure continues to remain a major cause of morbidity and mortality despite advances in medical therapies. Thus far, the precise role of coagulation factors in congestive heart failure is unknown. Further investigations are needed to elucidate the pathophysiology of congestive heart failure and coagulation factors.

  8. Analysis of gas composition of intravascular bubbles produced by decompression.

    PubMed

    Ishiyama, A

    1983-06-01

    The gas composition of intravascular bubbles produced by decompression was investigated in rabbits using gas chromatography. The animals were exposed to 8 ATA for 30 min. All samples of bubbles were taken from the animals under 0.2 ATA pressure gradient so that no air could enter the sampling system from the outside. The percentage of carbon dioxide in the bubbles tended to decrease at first and then increased with post-decompression time. On the other hand, the percentage of oxygen tended to change in the opposite manner. Actual analysis of bubbles in the living decompressed animals indicates that carbon dioxide may be an outstanding factor in the initiation and early growth of bubbles. In view of this, Haldane's classical maximum supersaturation limit for avoiding decompression sickness should be examined and possibly modified for gases other than nitrogen.

  9. Intravascular Myopericytoma in the Heel: Case Report and Literature Review

    PubMed Central

    Valero, José; Salcini, José L.; Gordillo, Luis; Gallart, José; González, David; Deus, Javier; Lahoz, Manuel

    2015-01-01

    Abstract Intravascular myopericytoma (IVMP), regarded as a variant of myopericytoma, is a rare tumor. Very few cases have been described, none in the foot. The first case of IVMP located in the heel of the foot is described in this article. A literature review is reported of all cases of IVMP published in the English literature. A 48-year-old man possessed an IVMP on the heel of the right foot. The physical examination and histopathological and ultrasound studies are described. The literature review yielded 5 cases of IVMP, 2 of which were in the thigh and 1 each in the oral mucosa, the periorbital region, and the leg. The possibility that these lesions may be malignant suggests that the histopathological study of vascular tumors should include immunohistochemical tests. PMID:25789958

  10. Mathematical Modeling of Intravascular Blood Coagulation under Wall Shear Stress

    PubMed Central

    Rukhlenko, Oleksii S.; Dudchenko, Olga A.; Zlobina, Ksenia E.; Guria, Georgy Th.

    2015-01-01

    Increased shear stress such as observed at local stenosis may cause drastic changes in the permeability of the vessel wall to procoagulants and thus initiate intravascular blood coagulation. In this paper we suggest a mathematical model to investigate how shear stress-induced permeability influences the thrombogenic potential of atherosclerotic plaques. Numerical analysis of the model reveals the existence of two hydrodynamic thresholds for activation of blood coagulation in the system and unveils typical scenarios of thrombus formation. The dependence of blood coagulation development on the intensity of blood flow, as well as on geometrical parameters of atherosclerotic plaque is described. Relevant parametric diagrams are drawn. The results suggest a previously unrecognized role of relatively small plaques (resulting in less than 50% of the lumen area reduction) in atherothrombosis and have important implications for the existing stenting guidelines. PMID:26222505

  11. Impact of Intravascular Hemolysis in Malaria on Liver Dysfunction

    PubMed Central

    Dey, Sumanta; Bindu, Samik; Goyal, Manish; Pal, Chinmay; Alam, Athar; Iqbal, Mohd. Shameel; Kumar, Rahul; Sarkar, Souvik; Bandyopadhyay, Uday

    2012-01-01

    We have investigated the impact of persistent intravascular hemolysis on liver dysfunction using the mouse malaria model. Intravascular hemolysis showed a positive correlation with liver damage along with the increased accumulation of free heme and reactive oxidants in liver. Hepatocytes overinduced heme oxygenase-1 (HO-1) to catabolize free heme in building up defense against this pro-oxidant milieu. However, in a condition of persistent free heme overload in malaria, the overactivity of HO-1 resulted in continuous transient generation of free iron to favor production of reactive oxidants as evident from 2′,7′-dichlorofluorescein fluorescence studies. Electrophoretic mobility shift assay documented the activation of NF-κB, which in turn up-regulated intercellular adhesion molecule 1 as evident from chromatin immunoprecipitation studies. NF-κB activation also induced vascular cell adhesion molecule 1, keratinocyte chemoattractant, and macrophage inflammatory protein 2, which favored neutrophil extravasation and adhesion in liver. The infiltration of neutrophils correlated positively with the severity of hemolysis, and neutrophil depletion significantly prevented liver damage. The data further documented the elevation of serum TNFα in infected mice, and the treatment of anti-TNFα antibodies also significantly prevented neutrophil infiltration and liver injury. Deferoxamine, which chelates iron, interacts with free heme and bears antioxidant properties that prevented oxidative stress, NF-κB activation, neutrophil infiltration, hepatocyte apoptosis, and liver damage. Furthermore, the administration of N-acetylcysteine also prevented NF-κB activation, neutrophil infiltration, hepatocyte apoptosis, and liver damage. Thus, hepatic free heme accumulation, TNFα release, oxidative stress, and NF-κB activation established a link to favor neutrophil infiltration in inducing liver damage during hemolytic conditions in malaria. PMID:22696214

  12. Interstitial rotating shield brachytherapy for prostate cancer

    SciTech Connect

    Adams, Quentin E. Xu, Jinghzu; Breitbach, Elizabeth K.; Li, Xing; Rockey, William R.; Kim, Yusung; Wu, Xiaodong; Flynn, Ryan T.; Enger, Shirin A.

    2014-05-15

    Purpose: To present a novel needle, catheter, and radiation source system for interstitial rotating shield brachytherapy (I-RSBT) of the prostate. I-RSBT is a promising technique for reducing urethra, rectum, and bladder dose relative to conventional interstitial high-dose-rate brachytherapy (HDR-BT). Methods: A wire-mounted 62 GBq{sup 153}Gd source is proposed with an encapsulated diameter of 0.59 mm, active diameter of 0.44 mm, and active length of 10 mm. A concept model I-RSBT needle/catheter pair was constructed using concentric 50 and 75 μm thick nickel-titanium alloy (nitinol) tubes. The needle is 16-gauge (1.651 mm) in outer diameter and the catheter contains a 535 μm thick platinum shield. I-RSBT and conventional HDR-BT treatment plans for a prostate cancer patient were generated based on Monte Carlo dose calculations. In order to minimize urethral dose, urethral dose gradient volumes within 0–5 mm of the urethra surface were allowed to receive doses less than the prescribed dose of 100%. Results: The platinum shield reduced the dose rate on the shielded side of the source at 1 cm off-axis to 6.4% of the dose rate on the unshielded side. For the case considered, for the same minimum dose to the hottest 98% of the clinical target volume (D{sub 98%}), I-RSBT reduced urethral D{sub 0.1cc} below that of conventional HDR-BT by 29%, 33%, 38%, and 44% for urethral dose gradient volumes within 0, 1, 3, and 5 mm of the urethra surface, respectively. Percentages are expressed relative to the prescription dose of 100%. For the case considered, for the same urethral dose gradient volumes, rectum D{sub 1cc} was reduced by 7%, 6%, 6%, and 6%, respectively, and bladder D{sub 1cc} was reduced by 4%, 5%, 5%, and 6%, respectively. Treatment time to deliver 20 Gy with I-RSBT was 154 min with ten 62 GBq {sup 153}Gd sources. Conclusions: For the case considered, the proposed{sup 153}Gd-based I-RSBT system has the potential to lower the urethral dose relative to HDR-BT by 29

  13. Urethral toxicity after LDR brachytherapy: experience in Japan.

    PubMed

    Tanaka, Nobumichi; Asakawa, Isao; Hasegawa, Masatoshi; Fujimoto, Kiyohide

    2015-01-01

    Urinary toxicity is common after low-dose-rate (LDR) brachytherapy, and the resolution of urinary toxicity is a concern. In particular, urinary frequency is the most common adverse event among the urinary toxicities. We have previously reported that approximately 70% of patients experience urinary frequency during the first 6 months after seed implantation. Most urinary adverse events were classified as Grade 1, and Grade 2 or higher adverse events were rare. The incidence of urinary retention was approximately 2-4%. A high International Prostate Symptom Score before seed implantation was an independent predictor of acute urinary toxicity of Grade 2 or higher. Several previous reports from the United States also supported this trend. In Japan, LDR brachytherapy was legally approved in 2003. A nationwide prospective cohort study entitled Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation was initiated in July 2005. It is an important issue to limit urinary toxicities in patients who undergo LDR brachytherapy.

  14. Brachytherapy in the treatment of skin cancer: an overview.

    PubMed

    Skowronek, Janusz

    2015-10-01

    The incidence of skin cancer worldwide is constantly growing and it is the most frequently diagnosed tumor. Brachytherapy (BT) in particular localizations is a valuable tool of the exact radiation depot inside the tumor mass. In localizations such as the face, skull skin and inoperable tumors, relapses after surgery, radiotherapy are usually not suitable for primary or secondary invasive treatment. Brachytherapy is a safe procedure for organs at risk according to rapid fall of a dose outside the axis of the applicator with satisfactory dose localization inside the target. The complications rate is acceptable and treatment costs are low. In some tumors (great skin lesions in the scalp, near eyes or on the nose) BT allows for a great dose reduction in surrounding healthy tissues. Brachytherapy provides minimal dose delivery to surrounding healthy tissue, thus enabling good functional and cosmetic results. Treatment is possible almost in all cases on an outpatient basis. PMID:26759545

  15. Validation of GPUMCD for low-energy brachytherapy seed dosimetry

    SciTech Connect

    Hissoiny, Sami; Ozell, Benoit; Despres, Philippe; Carrier, Jean-Francois

    2011-07-15

    Purpose: To validate GPUMCD, a new package for fast Monte Carlo dose calculations based on the GPU (graphics processing unit), as a tool for low-energy single seed brachytherapy dosimetry for specific seed models. As the currently accepted method of dose calculation in low-energy brachytherapy computations relies on severe approximations, a Monte Carlo based approach would result in more accurate dose calculations, taking in to consideration the patient anatomy as well as interseed attenuation. The first step is to evaluate the capability of GPUMCD to reproduce low-energy, single source, brachytherapy calculations which could ultimately result in fast and accurate, Monte Carlo based, brachytherapy dose calculations for routine planning. Methods: A mixed geometry engine was integrated to GPUMCD capable of handling parametric as well as voxelized geometries. In order to evaluate GPUMCD for brachytherapy calculations, several dosimetry parameters were computed and compared to values found in the literature. These parameters, defined by the AAPM Task-Group No. 43, are the radial dose function, the 2D anisotropy function, and the dose rate constant. These three parameters were computed for two different brachytherapy sources: the Amersham OncoSeed 6711 and the Imagyn IsoStar IS-12501. Results: GPUMCD was shown to yield dosimetric parameters similar to those found in the literature. It reproduces radial dose functions to within 1.25% for both sources in the 0.5< r <10 cm range. The 2D anisotropy function was found to be within 3% at r = 5 cm and within 4% at r = 1 cm. The dose rate constants obtained were within the range of other values reported in the literature.Conclusion: GPUMCD was shown to be able to reproduce various TG-43 parameters for two different low-energy brachytherapy sources found in the literature. The next step is to test GPUMCD as a fast clinical Monte Carlo brachytherapy dose calculations with multiple seeds and patient geometry, potentially providing

  16. Current state of the art brachytherapy treatment planning dosimetry algorithms

    PubMed Central

    Pantelis, E; Karaiskos, P

    2014-01-01

    Following literature contributions delineating the deficiencies introduced by the approximations of conventional brachytherapy dosimetry, different model-based dosimetry algorithms have been incorporated into commercial systems for 192Ir brachytherapy treatment planning. The calculation settings of these algorithms are pre-configured according to criteria established by their developers for optimizing computation speed vs accuracy. Their clinical use is hence straightforward. A basic understanding of these algorithms and their limitations is essential, however, for commissioning; detecting differences from conventional algorithms; explaining their origin; assessing their impact; and maintaining global uniformity of clinical practice. PMID:25027247

  17. Dosimetric characteristics of a new unit for electronic skin brachytherapy

    PubMed Central

    Garcia-Martinez, Teresa; Chan, Jan-Pieter; Perez-Calatayud, Jose

    2014-01-01

    Purpose Brachytherapy with radioactive high dose rate (HDR) 192Ir source is applied to small skin cancer lesions, using surface applicators, i.e. Leipzig or Valencia type. New developments in the field of radiotherapy for skin cancer include electronic brachytherapy. This technique involves the placement of an HDR X-ray source close to the skin, therefore combining the benefits of brachytherapy with the reduced shielding requirements and targeted energy of low energy X-rays. Recently, the Esteya® Electronic Brachytherapy System (Esteya EBS, Elekta AB-Nucletron, Stockholm, Sweden) has been developed specifically for HDR brachytherapy treatment of surface lesions. The system provides radionuclide free HDR brachytherapy by means of a small 69.5 kV X-ray source. The purpose of this study is to obtain the dosimetric characterization required for clinical implementation, providing the detailed methodology to perform the commissioning. Material and methods Flatness, symmetry and penumbra, percentage of depth dose (PDD), kV stability, HVL, output, spectrum, linearity, and leakage have been evaluated for a set of applicators (from 10 mm to 30 mm in diameter). Results Flatness and symmetry resulted better than 5% with around 1 mm of penumbra. The depth dose gradient is about 7%/mm. A kV value of 68.4 ± 1.0 kV (k = 1) was obtained, in good agreement with manufacturer data (69.5 kV). HVL was 1.85 mm Al. Dose rate for a typical 6 Gy to 7 Gy prescription resulted about 3.3 Gy/min and the leakage value was < 100 µGy/min. Conclusions The new Esteya® Electronic Brachytherapy System presents excellent flatness and penumbra as with the Valencia applicator case, combined with an improved PDD, allowing treatment of lesions of up to a depth of 5 mm in combination with reduced treatment duration. The Esteya unit allows HDR brachytherapy superficial treatment within a minimally shielded environment due its low energy. PMID:24790622

  18. Imaging method for monitoring delivery of high dose rate brachytherapy

    DOEpatents

    Weisenberger, Andrew G; Majewski, Stanislaw

    2012-10-23

    A method for in-situ monitoring both the balloon/cavity and the radioactive source in brachytherapy treatment utilizing using at least one pair of miniature gamma cameras to acquire separate images of: 1) the radioactive source as it is moved in the tumor volume during brachytherapy; and 2) a relatively low intensity radiation source produced by either an injected radiopharmaceutical rendering cancerous tissue visible or from a radioactive solution filling a balloon surgically implanted into the cavity formed by the surgical resection of a tumor.

  19. Intravascular large B-cell lymphoma with hemophagocytic syndrome (Asian variant) in a Caucasian patient.

    PubMed

    Fung, Kar-Ming; Chakrabarty, Jennifer H; Kern, William F; Magharyous, Hany; Gehrs, Bradley C; Li, Shibo

    2012-01-01

    Intravascular lymphoma is an aggressive and extremely rare extranodal lymphoma with neoplastic lymphoid cells confined exclusively within intravascular spaces. The histopathologic findings are subtle due to the rarity of the neoplastic cells in blood vessels. Clinical presentations are non-specific and focal space-occupying lesions or lymphoadenopathy are always lacking. It is a diagnostic challenge. Secondary hemophagocytic syndrome is uncommon and is typically associated with infection, malignancy, and suppressed immune states. Intravascular lymphoma has a strong association with hemophagocytic syndrome in Asian patients, the so-called "Asian variant", but not in Western patients. We report a case of intravascular B-cell lymphoma in a Caucasian patient associated with secondary hemophagocytic syndrome. The patient was diagnosed by core liver biopsy and successfully treated. This case demonstrates the importance of high index of suspicion and astute histopathologic examination in recognition of this unusual clinical and pathologic combination.

  20. [The usefulness of intravascular echography during the percutaneous dilatation of aortic coarctation].

    PubMed

    Goicolea, F J; Macaya, C; Iñíguez, A; Alfonso, F; Hernández Antolín, R; Vila i Costa, I; Zamorano, J; Egocheaga, I; Zarco, P

    1992-01-01

    An intravascular ultrasound study was performed in a patient, to assess the anatomy of aortic coarctation and the results obtained after percutaneous dilation with a balloon catheter. Intravascular ultrasound imaging provides important additional information, not obtainable with other diagnostic procedures, regarding aortic wall structure and thickness. After balloon dilation, aortic disruption was clearly observed, accounting, together with the stretching of the outer layers of the aortic wall, for the increase in aortic luminal area. Intravascular ultrasound permitted also the accurate assessment of the improvement obtained. Intravascular imaging was clearly superior not only to conventional angiography, but also to transesophageal echocardiography in detecting the mechanism of dilation. We conclude that ultravascular ultrasound, with the additional information that it provides, may help in the selection of patients for percutaneous dilation of the coarctation as well as contributing to the identification of the mechanism of dilation.

  1. Calibration of multiple LDR brachytherapy sources

    SciTech Connect

    DeWerd, Larry A.; Micka, John A.; Holmes, Shannon M.; Bohm, Tim D.

    2006-10-15

    A trend is underway toward the use of prepackaged low dose rate brachytherapy sources, which come in the form of strands, coiled line sources, preloaded needles, and sterile cartridge packs. Since the medical physicist is responsible for verification of source strength prior to patient treatment, development of prepackaged source strength verification methods is needed. Existing guidelines are reviewed to establish the situation that medical physicists find with respect to prepackaged sources. This investigation presents an experimental evaluation of the effect of some of these multiseed geometries on source strength measurements. Multiseed strands and coils, whether {sup 125}I, {sup 103}Pd, or {sup 192}Ir can be measured in a chamber with a long, sensitive axial length with a uniform response. Sterile seed cartridge packs can also be measured but require a correction factor to be applied. Sources in needles, however, cannot be measured in the needle since there is too great a variation in needle composition and needle tolerance thickness. Removing these seeds from the needle into a sterile measurement insert, which maintains sterility is a practical source strength verification method, similar to those done for multiple seed configurations in a well chamber with adequate axial uniformity. Values are compared with individual air kerma strength calibrations, and correction factors, are presented where needed. In each case, care must be taken to maintain sterility as multiple seeds are measured in well chamber inserts.

  2. Radiotherapy and brachytherapy for recurrent colorectal cancer

    SciTech Connect

    Nag, S. )

    1991-05-01

    Radical surgical excision of locoregional recurrence of colorectal carcinoma usually produces the best survival and should be attempted whenever possible. However, recurrences are often unresectable; hence palliative local therapy may be indicated. There are several options for the radiation therapy of local, unresectable, recurrent, or metastatic colorectal cancer. Whole pelvis irradiation of 4,000-5,000 cGy followed by a coned-down boost of 1,000-1,500 cGy generally provides good symptomatic palliation in 80-90% of patients, but long-term control or cure is rarely achieved. External beam irradiation of 2,000-3,000 cGy to the whole liver with or without concurrent chemotherapy may be used for palliation of metastatic disease to the liver. A combination of intraoperative radiation therapy applied directly to the tumor bed and external beam irradiation may improve local control and survival rates. Multiple options are available for the intraoperative use of brachytherapy which can deliver high radiation doses to the residual tumor, or tumor bed, sparing normal tissue.

  3. New trick for removal of intravascular retained foreign body: a case report and review of literature.

    PubMed

    Mousa, Albeir Y; Gill, Gurpreet; Aburahma, Ali F

    2014-01-01

    A 54-year-old male presented to the vascular service for an urgent inpatient consultation. During an infusaport removal, the catheter was accidentally disconnected and lost intravascularly within the left subclavian vein, with the tip still in the right ventricle. We report on a novel technique for removing such intravascular foreign bodies (FBs), which will add a valuable technical option to our existing armamentarium regarding intracorporeal FB removal.

  4. Intravascular Large B-Cell Lymphoma: A Difficult Diagnostic Challenge.

    PubMed

    Khan, Maria S; McCubbin, Mark; Nand, Sucha

    2014-01-01

    Case Presentation. A 69-year-old Hispanic male, with a past history of diabetes and coronary disease, was admitted for fever, diarrhea, and confusion of 4 weeks duration. Physical examination showed a disoriented patient with multiple ecchymoses, possible ascites, and bilateral scrotal swelling. Hemoglobin was 6.7, prothrombin time (PT) 21.4 seconds with international normalized ratio 2.1, partial thromboplastin time (PTT) 55.6 seconds, fibrin split 10 µg/L, and lactate dehydrogenase (LDH) 1231 IU/L. Except for a positive DNA test for Epstein-Barr virus (EBV) infection, extensive diagnostic workup for infections, malignancy, or a neurological cause was negative. Mixing studies revealed a nonspecific inhibitor of PT and PTT but Factor VIII levels were normal. The patient was empirically treated with antibiotics but developed hypotension and died on day 27 of admission. At autopsy, patient was found to have intravascular diffuse large B-cell lymphoma involving skin, testes, lung, and muscles. The malignant cells were positive for CD20, CD791, Mum-1, and Pax-5 and negative for CD3, CD5, CD10, CD30, and Bcl-6. The malignant cells were 100% positive for Ki-67. Discussion. Intravascular large cell B-cell lymphoma (IVLBCL) is rare form of diffuse large B-cell lymphoma and tends to proliferate within small blood vessels, particularly capillaries and postcapillary venules. The cause of its affinity for vascular bed remains unknown. In many reports, IVLBCL was associated with HIV, HHV8, and EBV infections. The fact that our case showed evidence of EBV infection lends support to the association of this diagnosis to viral illness. The available literature on this subject is scant, and in many cases, the diagnosis was made only at autopsy. The typical presentation of this disorder is with B symptoms, progressive neurologic deficits, and skin findings. Bone marrow, spleen, and liver are involved in a minority of patients. Nearly all patients have elevated LDH, and about 65% are

  5. Intravascular papillary endothelial hyperplasia: histomorphological and immunohistochemical features

    PubMed Central

    2013-01-01

    Background Intravascular papillary endothelial hyperplasia (IPEH) is a benign intravascular process with features mimicking other benign and malignant vascular proliferations. IPEH lesions predominate in the head-neck region and the extremities. The characteristic histomorphological feature of IPEH is a papillary structure covered with hyperplastic endothelial cells within the vascular lumen. It is critical that this clinically benign lesion should not be mistaken for well-differentiated vascular tumors. In addition to the characteristic histological features, other useful diagnostic features included the intra-luminal location of the lesion, an intimate association with the organizing thrombus, the absence of necrosis, cellular pleomorphism, and mitotic activity. In addition, immunohistochemistry may indicate the vascular origin and proliferative index. In this study, we evaluated histomorphological and immunohistochemical findings (CD31, CD34, FVIII, type IV collagen, SMA, MSA, CD105, and Ki-67 staining) of ten IPEH cases. Methods Ten IPEH cases were re-examined for a panel of histomorphological and immunohistochemical features. CD31, CD34, FVIII, Type IV collagen, SMA and MSA antibodies utilized for immunohistochemical analysis. The histomorphological and immunohistochemical findings were evaluated by two independent pathologists using light microscopy. Results All ten cases involved intraluminal lesions with characteristic features of IPEH. All ten cases (100%) were stained positive for CD31 and CD34. The degree of staining with FVIII, type IV collagen, SMA, and MSA was variable. Conclusion In this series of specimens, CD31 and CD34 were the most sensitive markers indicating the vascular origin of the lesion. Staining for the other vascular markers (FVIII, type IV collagen, SMA and MSA) was variable. Different maturation degrees of lesions may account for the variation in immunohistochemical staining. Few previous investigations evaluated a wide range of

  6. Initial application of digital tomosynthesis to improve brachytherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Baydush, Alan H.; Mirzaei McKee, Mahta; King, June; Godfrey, Devon J.

    2007-03-01

    We present preliminary investigations that examine the feasibility of incorporating volumetric images generated using digital tomosynthesis into brachytherapy treatment planning. The Integrated Brachytherapy Unit (IBU) at our facility consists of an L-arm, C-arm isocentric motion system with an x-ray tube and fluoroscopic imager attached. Clinically, this unit is used to generate oblique, anterior-posterior, and lateral images for simple treatment planning and dose prescriptions. Oncologists would strongly prefer to have volumetric data to better determine three dimensional dose distributions (dose-volume histograms) to the target area and organs at risk. Moving the patient back and forth to CT causes undo stress on the patient, allows extensive motion of organs and treatment applicators, and adds additional time to patient treatment. We propose to use the IBU imaging system with digital tomosynthesis to generate volumetric patient data, which can be used for improving treatment planning and overall reducing treatment time. Initial image data sets will be acquired over a limited arc of a human-like phantom composed of real bones and tissue equivalent material. A brachytherapy applicator will be incorporated into one of the phantoms for visualization purposes. Digital tomosynthesis will be used to generate a volumetric image of this phantom setup. This volumetric image set will be visually inspected to determine the feasibility of future incorporation of these types of images into brachytherapy treatment planning. We conclude that initial images using the tomosynthesis reconstruction technique show much promise and bode well for future work.

  7. Introduction of Transperineal Image-Guided Prostate Brachytherapy

    SciTech Connect

    Aronowitz, Jesse N.

    2014-07-15

    The modern prostate brachytherapy procedure is characterized by ultrasound guidance, template assistance, and a return to a “closed” transperineal approach. This review traces the introduction and evolution of these elements and charts the development of the procedure from the ashes of previous, failed efforts.

  8. Verification of Oncentra brachytherapy planning using independent calculation

    NASA Astrophysics Data System (ADS)

    Safian, N. A. M.; Abdullah, N. H.; Abdullah, R.; Chiang, C. S.

    2016-03-01

    This study was done to investigate the verification technique of treatment plan quality assurance for brachytherapy. It is aimed to verify the point doses in 192Ir high dose rate (HDR) brachytherapy between Oncentra Masterplan brachytherapy treatment planning system and independent calculation software at a region of rectum, bladder and prescription points for both pair ovoids and full catheter set ups. The Oncentra TPS output text files were automatically loaded into the verification programme that has been developed based on spreadsheets. The output consists of source coordinates, desired calculation point coordinates and the dwell time of a patient plan. The source strength and reference dates were entered into the programme and then dose point calculations were independently performed. The programme shows its results in a comparison of its calculated point doses with the corresponding Oncentra TPS outcome. From the total of 40 clinical cases that consisted of two fractions for 20 patients, the results that were given in term of percentage difference, it shows an agreement between TPS and independent calculation are in the range of 2%. This programme only takes a few minutes to be used is preferably recommended to be implemented as the verification technique in clinical brachytherapy dosimetry.

  9. Photoacoustic imaging of prostate brachytherapy seeds with transurethral light delivery

    NASA Astrophysics Data System (ADS)

    Lediju Bell, Muyinatu A.; Guo, Xiaoyu; Song, Danny Y.; Boctor, Emad M.

    2014-03-01

    We present a novel approach to photoacoustic imaging of prostate brachytherapy seeds utilizing an existing urinary catheter for transurethral light delivery. Two canine prostates were surgically implanted with brachyther- apy seeds under transrectal ultrasound guidance. One prostate was excised shortly after euthanasia and fixed in gelatin. The second prostate was imaged in the native tissue environment shortly after euthanasia. A urinary catheter was inserted in the urethra of each prostate. A 1-mm core diameter optical fiber coupled to a 1064 nm Nd:YAG laser was inserted into the urinary catheter. Light from the fiber was either directed mostly parallel to the fiber axis (i.e. end-fire fire) or mostly 90° to the fiber axis (i.e. side-fire fiber). An Ultrasonix SonixTouch scanner, transrectal ultrasound probe with curvilinear (BPC8-4) and linear (BPL9-5) arrays, and DAQ unit were utilized for synchronized laser light emission and photoacoustic signal acquisition. The implanted brachytherapy seeds were visualized at radial distances of 6-16 mm from the catheter. Multiple brachytherapy seeds were si- multaneously visualized with each array of the transrectal probe using both delay-and-sum (DAS) and short-lag spatial coherence (SLSC) beamforming. This work is the first to demonstrate the feasibility of photoacoustic imaging of prostate brachytherapy seeds using a transurethral light delivery method.

  10. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Radionuclide brachytherapy source. 892.5730 Section 892.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... a source of nuclear radiation for therapy. (b) Classification. Class II....

  11. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Radionuclide brachytherapy source. 892.5730 Section 892.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... a source of nuclear radiation for therapy. (b) Classification. Class II....

  12. Photoacoustic imaging of prostate brachytherapy seeds in ex vivo prostate

    NASA Astrophysics Data System (ADS)

    Kuo, Nathanael; Kang, Hyun Jae; DeJournett, Travis; Spicer, James; Boctor, Emad

    2011-03-01

    The localization of brachytherapy seeds in relation to the prostate is a key step in intraoperative treatment planning (ITP) for improving outcomes in prostate cancer patients treated with low dose rate prostate brachytherapy. Transrectal ultrasound (TRUS) has traditionally been the modality of choice to guide the prostate brachytherapy procedure due to its relatively low cost and apparent ease of use. However, TRUS is unable to visualize seeds well, precluding ITP and producing suboptimal results. While other modalities such as X-ray and magnetic resonance imaging have been investigated to localize seeds in relation to the prostate, photoacoustic imaging has become an emerging and promising modality to solve this challenge. Moreover, photoacoustic imaging may be more practical in the clinical setting compared to other methods since it adds little additional equipment to the ultrasound system already adopted in procedure today, reducing cost and simplifying engineering steps. In this paper, we demonstrate the latest efforts of localizing prostate brachytherapy seeds using photoacoustic imaging, including visualization of multiple seeds in actual prostate tissue. Although there are still several challenges to be met before photoacoustic imaging can be used in the operating room, we are pleased to present the current progress in this effort.

  13. Human factors evaluation of remote afterloading brachytherapy - an overview

    SciTech Connect

    Schoenfeld, I.

    1994-12-31

    This report presents information from a research project aimed at understanding the causes of human errors in remote afterloading brachytherapy. The analysis determined functions, tasks, equipment, and personnel involoved, as well as cognitive, perceptual, and motor skills needed to perform the tasks.

  14. Monolithic CMUT on CMOS Integration for Intravascular Ultrasound Applications

    PubMed Central

    Zahorian, Jaime; Hochman, Michael; Xu, Toby; Satir, Sarp; Gurun, Gokce; Karaman, Mustafa; Degertekin, F. Levent

    2012-01-01

    One of the most important promises of capacitive micromachined ultrasonic transducer (CMUT) technology is integration with electronics. This approach is required to minimize the parasitic capacitances in the receive mode, especially in catheter based volumetric imaging arrays where the elements need to be small. Furthermore, optimization of the available silicon area and minimized number of connections occurs when the CMUTs are fabricated directly above the associated electronics. Here, we describe successful fabrication and performance evaluation of CMUT arrays for intravascular imaging on custom designed CMOS receiver electronics from a commercial IC foundry. The CMUT on CMOS process starts with surface isolation and mechanical planarization of the CMOS electronics to reduce topography. The rest of the CMUT fabrication is achieved by modifying a low temperature micromachining process through the addition of a single mask and developing a dry etching step to produce sloped sidewalls for simple and reliable CMUT to CMOS interconnection. This CMUT to CMOS interconnect method reduced the parasitic capacitance by a factor of 200 when compared with a standard wire bonding method. Characterization experiments indicate that the CMUT on CMOS elements are uniform in frequency response and are similar to CMUTs simultaneously fabricated on standard silicon wafers without electronics integration. Experiments on a 1.6 mm diameter dual-ring CMUT array with a 15 MHz center frequency show that both the CMUTs and the integrated CMOS electronics are fully functional. The SNR measurements indicate that the performance is adequate for imaging CTOs located 1 cm away from the CMUT array. PMID:23443701

  15. Role of Intravascular Ultrasound in Patients with Acute Myocardial Infarction

    PubMed Central

    Hong, Young Joon; Ahn, Youngkeun

    2015-01-01

    Rupture of a vulnerable plaque and subsequent thrombus formation are important mechanisms leading to the development of an acute myocardial infarction (AMI). Typical intravascular ultrasound (IVUS) features of AMI include plaque rupture, thrombus, positive remodeling, attenuated plaque, spotty calcification, and thin-cap fibroatheroma. No-reflow phenomenon was attributable to the embolization of thrombus and plaque debris that results from mechanical fragmentation of the vulnerable plaque by percutaneous coronary intervention (PCI). Several grayscale IVUS features including plaque rupture, thrombus, positive remodeling, greater plaque burden, decreased post-PCI plaque volume, and tissue prolapse, and virtual histology-IVUS features such as large necrotic corecontaining lesion and thin-cap fibroatheroma were the independent predictors of no-reflow phenomenon in AMI patients. Non-culprit lesions associated with recurrent events were more likely than those not associated with recurrent events to be characterized by a plaque burden of ≥70%, a minimal luminal area of ≤4.0 mm2, or to be classified as thin-cap fibroatheromas. PMID:26240578

  16. Quantitative recovery of pulmonary intravascular macrophages from sheep lungs.

    PubMed

    Rogers, R A; Tasat, D R; Warner, A E; Brain, J D

    1994-12-01

    Pulmonary intravascular macrophages (PIMs) adhere to the endothelium of lung capillaries and sequester circulating particles and pathogens from the blood. Iron oxide (gamma Fe2O3) 5 mg/kg, administered intravenously, specifically labeled PIMs in situ within the living sheep. Attempts to isolate gamma Fe2O3-labeled PIMs using vascular perfusion (VP) procedures yielded few cells. To improve recovery of PIMs, a proteolytic lung digestion (PLD) procedure was developed. Following PLD, gamma Fe2O3-containing PIMs were recovered by magnets and the amount of gamma Fe2O3 present measured by fluxgate magnetometry. Proteolytic lung digestion recovered 34% of the total gamma Fe2O3 in lung samples and yielded 2 x 10(5) PIMs/g lung with 95% viability. In contrast, VP recovered only 3% of the total gamma Fe2O3 in the lung; furthermore, less than 2% of the recovered gamma Fe2O3 was cell associated. Proteolytic lung digestion followed by magnetic separation is an effective way to recover viable sheep PIMs for in vitro study. PMID:7996045

  17. Microbial diversity on intravascular catheters from paediatric patients.

    PubMed

    Zhang, L; Marsh, N; Long, D; Wei, M; Morrison, M; Rickard, C M

    2015-12-01

    Microorganisms play important roles in intravascular catheter (IVC)-related infections, which are the most serious complications in children with IVCs, leading to increased hospitalisation, intensive care admissions, extensive antibiotic treatment and mortality. A greater understanding of bacterial communities is needed in order to improve the management of infections. We describe here the systematic culture-independent evaluation of IVC bacteriology in IVC biofilms. Twenty-four IVC samples (six peripherally inserted central catheters, eight central venous catheters and ten arterial catheters) were collected from 24 paediatric patients aged 0 to 14 years old. Barcoded amplicon libraries produced from genes coding 16S rRNA and roll-plate culture methods were used to determine the microbial composition of these samples. From a total of 1,043,406 high-quality sequence reads, eight microbial phyla and 136 diverse microbial genera were detected, separated into 12,224 operational taxonomic units (OTUs). Three phyla (Actinobacteria, Firmicutes and Proteobacteria) predominate the microorganism on the IVC surfaces, with Firmicutes representing nearly half of the OTUs found. Among the Firmicutes, Staphylococcus (15.0% of 16S rRNA reads), Streptococcus (9.6%) and Bacillus (6.1%) were the most common. Community composition did not appear to be affected by patients' age, gender, antibiotic treatment or IVC type. Differences in IVC microbiota were more likely associated with events arising from catheter dwell time, rather than the type of IVC used. PMID:26515578

  18. Impact of microbial attachment on intravascular catheter-related infections.

    PubMed

    Zhang, Li; Gowardman, John; Rickard, Claire M

    2011-07-01

    Intravascular catheters (IVCs) are the most frequently used medical devices in hospitals. However, they are associated with life-threatening IVC-related bloodstream infection (IVC-BSI), which is one of the main hospital-acquired infections, and continue to be associated with morbidity, mortality and additional medical cost. Most published studies focus on measuring the rate of IVC-BSIs and addressing their importance, but only a few studies have mentioned the possible routes for microbes entering the bloodstream, which would help in developing effective prevention methods, and large trial studies are lacking. Some studies on IVC-BSIs have reported the most frequently isolated microbes, but caution needs to be made since many fastidious microbes are not isolated under current laboratory conditions. Although it is known that microbes colonise IVC surfaces and develop biofilms, leading to IVC-BSI, the relationships of microbial biofilms with patients' symptoms or outcomes remain unclear. Here we discuss the knowledge gained from microbial research in other (non-IVC) medical and non-medical applications that may be helpful in understanding the IVC context. In addition, published theory and data regarding microbial colonisation and biofilm development specifically in IVCs are reviewed. More research is needed to explore mechanisms of IVC-BSI and to provide superior prevention strategies.

  19. Acoustic determination of early stages of intravascular blood coagulation.

    PubMed

    Uzlova, Svetlana G; Guria, Konstantin G; Guria, Georgy Th

    2008-10-13

    The blood coagulation system (BCS) is a complex biological system playing a principal role in the maintenance of haemostasis. Insufficient activity of the BCS may lead to bleeding and blood loss (e.g. in the case of haemophilia). On the other hand, excessive activity may cause intravascular blood coagulation, thromboses and embolization. Most of the methods currently used for BCS monitoring suffer from the major disadvantage of being invasive. The purpose of the present work is to demonstrate the feasibility of using ultrasonic methods for non-invasive registration of the early stages of blood coagulation processes in intensive flows. With this purpose, a special experimental set-up was designed, facilitating the simultaneous detection of optical and acoustic signals during the clotting process. It was shown that (i) as microemboli appear in the flow during the early stage of blood coagulation, the intensity of the Doppler signal increases twofold, and (ii) microemboli formation in the early stages of blood clotting always reveals itself through an acoustic contrast. Both of these effects are well defined, so we hope that they may be used for non-invasive BCS monitoring in clinical practice.

  20. [Progress in diagnosis and treatment for disseminated intravascular coagulation].

    PubMed

    Wada, Hideo; Matsumoto, Takeshi; Aota, Takumi; Yamashita, Yoshiki

    2015-02-01

    As the development of a hypercoagulable state in the setting of disseminated intravascular coagulation (DIC) induces localized infection, therapy for DIC should be evaluated according to the findings of examinations for both severe sepsis and DIC. DIC is classified into the following types: "bleeding type," "organ failure type," "asymptomatic type," and "complication type." The "bleeding type" and "organ failure type" are considered to reflect the "plasmin inhibitor (PI) deficiency type" and "antithrombin (AT) deficiency type," respectively. In order to improve the diagnosis of DIC, in particular limitations in global coagulation tests, the Japanese Society of Thrombosis and Hemostasis recently proposed tentative diagnostic criteria for DIC using hemostatic molecular markers and AT. The recommendations for treatment of DIC, especially the use of AT concentrates, recombinant activated protein C and thrombomodulin, vary among several guidelines for the management of DIC. These agents inhibit the effects of key proteases in activating coagulation and consequently exert an anti-inflammatory effect on DIC. Hence, it is necessary to extensively evaluate these agents in well-conducted clinical trials.

  1. Back to the future: testing in disseminated intravascular coagulation.

    PubMed

    Toh, Cheng-Hock; Downey, Colin

    2005-11-01

    Following on from the first clinical observations on disseminated intravascular coagulation (DIC) in the nineteenth century, the dawn of laboratory testing for DIC began with the availability of assays that characterized the extrinsic and intrinsic pathways of coagulation. Markedly increased clotting times were the hallmark of DIC. As the understanding of the biochemistry of haemostasis and thrombosis improved, new tests were developed based on the molecular players that participate in the process. However, many are non-specific for DIC and/or are unwieldy in performance to keep apace with the demands of the acute clinical setting. The renewed emphasis in DIC for the modern laboratory of the twenty-first century has seen a return to the simple, rapid and practical global tests of coagulation within scoring systems that also capture the pathophysiological continuum by trend analysis. Additionally, new technologies based on these simple tests of coagulation hold promise in also indicating the in vivo interplay between coagulation and inflammation during DIC.

  2. Diagnostic criteria and laboratory tests for disseminated intravascular coagulation.

    PubMed

    Wada, Hideo; Matsumoto, Takeshi; Hatada, Tuyoshi

    2012-12-01

    Three diagnostic criteria for disseminated intravascular coagulation (DIC) have been established by the Japanese Ministry of Health, Labor and Welfare, the International Society on Thrombosis and Hemostasis (ISTH) and the Japanese Association for Acute Medicine. The diagnostic criteria involving global coagulation tests, such as the Japanese Ministry of Health, Labor and Welfare criteria and the ISTH overt diagnostic criteria, are first-generation DIC diagnostic criteria, those involving global coagulation tests and changes in these tests such as the Japanese Association for Acute Medicine criteria, are second-generation DIC diagnostic criteria, and those including non-overt DIC diagnostic criteria involving global coagulation tests, changes in these tests and hemostatic molecular markers will be the future (third-generation) DIC diagnostic criteria. There are no significant differences in the three diagnostic criteria with respect to predicting poor outcomes. Therefore, the third generation of diagnostic criteria including hemostatic molecular markers is expected to be established. Standardization and the determination of adequate cutoff values should be required for each laboratory test.

  3. Disseminated intravascular coagulopathy: manifestations after a routine dental extraction.

    PubMed

    Peters, Kelly A; Triolo, Peter T; Darden, Daryle L

    2005-04-01

    Clinical signs and symptoms of acute disseminated intravascular coagulopathy (DIC) include bleeding from body orifices, such as the nose, mouth, or ear, bleeding from an intravenous (IV) site, areas of ecchymosis, or blood in the urine or stool. The underlying disease triggering DIC usually determines the clinical presentation. However, patients with chronic DIC (compensated DIC) may possess subclinical signs and symptoms, and the bleeding disorder may only be identified through laboratory findings. In this compensated form, the triggering factor is exposed slowly and in small amounts (seen in malignancies and vasculitis), allowing replenishing of the augmented factors by the liver, adequate reticuloendothelial clearance of fibrin degradation products, and increased production of platelets, which prevent secondary fibrinolysis and the signs of bleeding. 1,4 We report a case of an 82-year-old male who presented to the emergency room 24 hours after a routine dental extraction with bleeding from the tooth socket, severe hypotension, and presence of ecchymosis on his chest. Clinical and radiographic exam revealed multiple thoracic and abdominal aortic aneurysms, as well as infrarenal and iliac aneurysms, continuous oral hemorrhage, and a unique presentation rarely documented in the literature: a bleeding tooth socket as the initial clinical sign and presentation of DIC.

  4. Low-artifact intravascular devices: MR imaging evaluation.

    PubMed

    Teitelbaum, G P; Ortega, H V; Vinitski, S; Stern, H; Tsuruda, J S; Mitchell, D G; Rifkin, M D; Bradley, W G

    1988-09-01

    Flow-phantom magnetic resonance (MR) imaging, with use of both spin-echo (SE) and gradient-echo (GRE) techniques at 1.5 T, was performed on the percutaneous Greenfield (beta-III titanium alloy [TMA wire]), Amplatz (MP32-N alloy), and Simon nitinol filters and TMA wire facsimiles of the bird's nest, Gunther, new retrievable, and Amplatz vena caval filters. SE imaging allowed detection of thrombi as small as 5 X 5 mm trapped within the percutaneous Greenfield, Simon nitinol, and TMA-wire facsimile filters; with the MP32-N Amplatz filter, a larger volume of thrombus (10 X 20-mm clots) was necessary for clot detection. GRE imaging allowed detection of intraluminal tilting of the percutaneous Greenfield and facsimile Amplatz (TMA-wire) filters. GRE imaging was useful for demonstrating postfilter turbulence due to clots, which was greatest for the Amplatz filter. Imaging of facsimile vascular devices made of tantalum or TMA wire did not cause the severe "black-hole" MR artifacts typical of the stainless-steel devices. SE and GRE imaging were very useful for determining caval patency in two patients with previously placed Mobin-Uddin filters. Noninvasive MR evaluation of blood vessels in the presence of a variety of low-artifact intravascular devices appears feasible. PMID:3406402

  5. Effect of intravascular cellular aggregate dissolution in postoperative patients.

    PubMed Central

    Dawidson, I; Barrett, J; Miller, E; Litwin, M S

    1975-01-01

    It was the purpose of this study to confirm whether the increase in packed cell (PC) viscosity that occurs in humans after elective surgery is accompanied by a decrease in total body O2 consumption as previously noted in animals, and further to define the effect of resolution of intravascular cellular aggregates (ICA) on these parameters. Thirty nine patients were studied. Total body O2 consumption was 76% of normal 6 hours postop, 81% of normal 24 hours postop and 87% of normal 48 hours postop. Twenty four hours after operation PC viscosity and increased markedly. Saline infusion had no significant effect on total body O2 consumption or PC viscosity, either pre- or postop, but WB viscosity decreased linearly in proportion in the drop in hematocrit. Resolution of ICA by dextran-40 infusion was associated with return of total body O2 consumption and PC viscosity to normal; a decrease in WB viscosity was disproportionately greater than would have been seen had the decrease been due solely to the drop in hematocrit. It is concluded that in humans surgical trauma causes an increase in PC viscosity and microcirculatory impairment as evidenced by a decrease in total body O2 consumption. Resolution of ICA by dextran-40 infusion reverses that detrimental changes. PMID:1190882

  6. Heartbeat OCT: in vivo intravascular megahertz-optical coherence tomography

    PubMed Central

    Wang, Tianshi; Pfeiffer, Tom; Regar, Evelyn; Wieser, Wolfgang; van Beusekom, Heleen; Lancee, Charles T.; Springeling, Geert; Krabbendam, Ilona; van der Steen, Antonius F.W.; Huber, Robert; van Soest, Gijs

    2015-01-01

    Cardiac motion artifacts, non-uniform rotational distortion and undersampling affect the image quality and the diagnostic impact of intravascular optical coherence tomography (IV-OCT). In this study we demonstrate how these limitations of IV-OCT can be addressed by using an imaging system that we called “Heartbeat OCT”, combining a fast Fourier Domain Mode Locked laser, fast pullback, and a micromotor actuated catheter, designed to examine a coronary vessel in less than one cardiac cycle. We acquired in vivo data sets of two coronary arteries in a porcine heart with both Heartbeat OCT, working at 2.88 MHz A-line rate, 4000 frames/s and 100 mm/s pullback speed, and with a commercial system. The in vivo results show that Heartbeat OCT provides faithfully rendered, motion-artifact free, fully sampled vessel wall architecture, unlike the conventional IV-OCT data. We present the Heartbeat OCT system in full technical detail and discuss the steps needed for clinical translation of the technology. PMID:26713214

  7. Calculated and measured brachytherapy dosimetry parameters in water for the Xoft Axxent X-Ray Source: An electronic brachytherapy source

    SciTech Connect

    Rivard, Mark J.; Davis, Stephen D.; DeWerd, Larry A.; Rusch, Thomas W.; Axelrod, Steve

    2006-11-15

    A new x-ray source, the model S700 Axxent trade mark sign X-Ray Source (Source), has been developed by Xoft Inc. for electronic brachytherapy. Unlike brachytherapy sources containing radionuclides, this Source may be turned on and off at will and may be operated at variable currents and voltages to change the dose rate and penetration properties. The in-water dosimetry parameters for this electronic brachytherapy source have been determined from measurements and calculations at 40, 45, and 50 kV settings. Monte Carlo simulations of radiation transport utilized the MCNP5 code and the EPDL97-based mcplib04 cross-section library. Inter-tube consistency was assessed for 20 different Sources, measured with a PTW 34013 ionization chamber. As the Source is intended to be used for a maximum of ten treatment fractions, tube stability was also assessed. Photon spectra were measured using a high-purity germanium (HPGe) detector, and calculated using MCNP. Parameters used in the two-dimensional (2D) brachytherapy dosimetry formalism were determined. While the Source was characterized as a point due to the small anode size, <1 mm, use of the one-dimensional (1D) brachytherapy dosimetry formalism is not recommended due to polar anisotropy. Consequently, 1D brachytherapy dosimetry parameters were not sought. Calculated point-source model radial dose functions at g{sub P}(5) were 0.20, 0.24, and 0.29 for the 40, 45, and 50 kV voltage settings, respectively. For 1

  8. HHV-8 and EBV-positive intravascular lymphoma: an unusual presentation of extracavitary primary effusion lymphoma

    PubMed Central

    Crane, Genevieve M.; Ambinder, Richard F.; Shirley, Courtney M.; Fishman, Elliot K.; Kasamon, Yvette L.; Taube, Janis M.; Borowitz, Michael J.; Duffield, Amy S.

    2014-01-01

    Intravascular lymphomas are rare and aggressive hematolymphoid tumors. Here we describe a human herpesvirus type-8/Kaposi sarcoma-associated herpesvirus (HHV-8/KSHV) and Epstein-Barr virus (EBV) positive intravascular lymphoma. The patient was a 59 year-old HIV-positive man who presented with diarrhea, abdominal pain, fevers, night sweats, and weight loss. Radiographic studies of the abdomen and pelvis revealed numerous subcentimeter nodules within the subcutaneous fat that lacked connection to the skin. An excisional biopsy demonstrated large atypical cells within vessels in the deep subcutaneous fat, and many of the vessels contained extensive organizing thrombi. The atypical cells lacked strong expression of most B-cell markers but were positive for MUM-1 and showed partial expression of several T-cell markers. An immunohistochemical stain for HHV-8 and an in situ hybridization for EBV were both positive in the neoplastic cells. The disease had a rapidly progressive and fatal course. This lymphoma appears to represent an entirely intravascular form of primary effusion lymphoma, and highlights the propensity for HHV-8 and EBV-positive lymphoid neoplasms to show aberrant expression of T-cell markers, illustrates the utility of skin biopsies for the diagnosis of intravascular lymphoma, and suggests that biopsies to evaluate for intravascular lymphoma should be relatively deep and include subcutaneous fat. PMID:24525514

  9. Percutaneous Retrieval of Misplaced Intravascular Foreign Objects with the Dormia Basket: An Effective Solution

    SciTech Connect

    Sheth, Rahul Someshwar, Vimal; Warawdekar, Gireesh

    2007-02-15

    Purpose. We report our experience of the retrieval of intravascular foreign body objects by the percutaneous use of the Gemini Dormia basket. Methods. Over a period of 2 years we attempted the percutaneous removal of intravascular foreign bodies in 26 patients. Twenty-six foreign bodies were removed: 8 intravascular stents, 4 embolization coils, 9 guidewires, 1 pacemaker lead, and 4 catheter fragments. The percutaneous retrieval was achieved with a combination of guide catheters and the Gemini Dormia basket. Results. Percutaneous retrieval was successful in 25 of 26 patients (96.2%). It was possible to remove all the intravascular foreign bodies with a combination of guide catheters and the Dormia basket. No complication occurred during the procedure, and no long-term complications were registered during the follow-up period, which ranged from 6 months to 32 months (mean 22.4 months overall). Conclusion. Percutaneous retrieval is an effective and safe technique that should be the first choice for removal of an intravascular foreign body.

  10. Imminent Cardiac Risk Assessment via Optical Intravascular Biochemical Analysis

    SciTech Connect

    Wetzel, D.; Wetzel, L; Wetzel, M; Lodder, R

    2009-01-01

    Heart disease is by far the biggest killer in the United States, and type II diabetes, which affects 8% of the U.S. population, is on the rise. In many cases, the acute coronary syndrome and/or sudden cardiac death occurs without warning. Atherosclerosis has known behavioral, genetic and dietary risk factors. However, our laboratory studies with animal models and human post-mortem tissue using FT-IR microspectroscopy reveal the chemical microstructure within arteries and in the arterial walls themselves. These include spectra obtained from the aortas of ApoE-/- knockout mice on sucrose and normal diets showing lipid deposition in the former case. Also pre-aneurysm chemical images of knockout mouse aorta walls, and spectra of plaque excised from a living human patient are shown for comparison. In keeping with the theme of the SPEC 2008 conference Spectroscopic Diagnosis of Disease this paper describes the background and potential value of a new catheter-based system to provide in vivo biochemical analysis of plaque in human coronary arteries. We report the following: (1) results of FT-IR microspectroscopy on animal models of vascular disease to illustrate the localized chemical distinctions between pathological and normal tissue, (2) current diagnostic techniques used for risk assessment of patients with potential unstable coronary syndromes, and (3) the advantages and limitations of each of these techniques illustrated with patent care histories, related in the first person, by the physician coauthors. Note that the physician comments clarify the contribution of each diagnostic technique to imminent cardiac risk assessment in a clinical setting, leading to the appreciation of what localized intravascular chemical analysis can contribute as an add-on diagnostic tool. The quality of medical imaging has improved dramatically since the turn of the century. Among clinical non-invasive diagnostic tools, laboratory tests of body fluids, EKG, and physical examination are

  11. [Relationship between the state of intravascular bubbles and microcirculation system].

    PubMed

    Yuan, J; Pan, L; Wang, Q; Ji, Z; Gao, J

    1996-08-01

    To confirm the hypothesis that air bubbles were unable to block the blood vessels and that the state of the intravascular bubbles was determined by the function of the circulatory system, 35 guinea pigs were pressurized then were decompressed to normal pressure. Microscopic observation was made of the bulbar conjunctival, dorsum auricular and subcutaneous vessels in 33 surviving animals. Air bubbles of different amounts, sizes and shapes were found in the dorsum auricular and subcutaneous vein of all the amimals and in the bulbar conjunctival oriridal artery of 16 animals, and in some cases the vessels were even filled with bubbles. The bubbles ran in the same direction and at the same speed as the blood flow. They could run in a backward, to-and-fro or sluggish flow. The bubbles looked shapeless and tended to break and divided into branch flows where the vessel branches. The bubbles were motionless at the proximal end of the artery occluded due to spasm or when the blood was stagnated. Under the action of the blood pressure the bubbles could expand the vessel and push forward. The bubbles showed a tendency of flowing with ease with the function of the vessel recovered. The results suggest that bubbles of any size in the vessel could easily change their shape under the action of the blood flow and pressure, and pass through vessels of any diameter and circulate with the blood. Only when a vessel was occluded due to spasm or the blood in a vessel was stagnated could the bubbles be motionless, but it was not that the bubbles blocked the vessel.

  12. Protection against high intravascular pressure in giraffe legs.

    PubMed

    Petersen, Karin K; Hørlyck, Arne; Ostergaard, Kristine H; Andresen, Joergen; Broegger, Torbjoern; Skovgaard, Nini; Telinius, Niklas; Laher, Ismael; Bertelsen, Mads F; Grøndahl, Carsten; Smerup, Morten; Secher, Niels H; Brøndum, Emil; Hasenkam, John M; Wang, Tobias; Baandrup, Ulrik; Aalkjaer, Christian

    2013-11-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along the artery. Histology of the isolated median artery confirmed dense sympathetic innervation at the narrowing. Structure and contractility of small arteries from muscular beds in the leg and neck were compared. The arteries from the legs demonstrated an increased media thickness-to-lumen diameter ratio, increased media volume, and increased numbers of smooth muscle cells per segment length and furthermore, they contracted more strongly than arteries from the neck (500 ± 49 vs. 318 ± 43 mmHg; n = 6 legs and neck, respectively). Finally, the transient increase in interstitial fluid pressure following injection of saline was 5.5 ± 1.7 times larger (n = 8) in the leg than in the neck. We conclude that 1) tissue compliance in the legs is low; 2) large arteries of the legs function as resistance arteries; and 3) structural adaptation of small muscle arteries allows them to develop an extraordinary tension. All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure.

  13. Mechanotransductional basis of endothelial cell response to intravascular bubbles.

    PubMed

    Klinger, Alexandra L; Pichette, Benjamin; Sobolewski, Peter; Eckmann, David M

    2011-10-01

    Vascular air embolism resulting from too rapid decompression is a well-known risk in deep-sea diving, aviation and space travel. It is also a common complication during surgery or other medical procedures when air or other endogenously administered gas is entrained in the circulation. Preventive and post-event treatment options are extremely limited for this dangerous condition, and none of them address the poorly understood pathophysiology of endothelial response to intravascular bubble presence. Using a novel apparatus allowing precise manipulation of microbubbles in real time fluorescence microscopy studies, we directly measure human umbilical vein endothelial cell responses to bubble contact. Strong intracellular calcium transients requiring extracellular calcium are observed upon cell-bubble interaction. The transient is eliminated both by the presence of the stretch activated channel inhibitor, gadolinium, and the transient receptor potential vanilliod family inhibitor, ruthenium red. No bubble induced calcium upsurge occurs if the cells are pretreated with an inhibitor of actin polymerization, cytochalasin-D. This study explores the biomechanical mechanisms at play in bubble interfacial interactions with endothelial surface layer (ESL) macromolecules, reassessing cell response after selective digestion of glycocalyx glycosoaminoglycans, hyaluran (HA) and heparin sulfate (HS). HA digestion causes reduction of cell-bubble adherence and a more rapid induction of calcium influx after contact. HS depletion significantly decreases calcium transient amplitudes, as does pharmacologically induced sydencan ectodomain shedding. The surfactant perfluorocarbon Oxycyte abolishes any bubble induced calcium transient, presumably through direct competition with ESL macromolecules for interfacial occupancy, thus attenuating the interactions that trigger potentially deleterious biochemical pathways.

  14. Supportive management strategies for disseminated intravascular coagulation. An international consensus.

    PubMed

    Squizzato, Alessandro; Hunt, Beverley J; Kinasewitz, Gary T; Wada, Hideo; Ten Cate, Hugo; Thachil, Jecko; Levi, Marcel; Vicente, Vicente; D'Angelo, Armando; Di Nisio, Marcello

    2016-05-01

    The cornerstone of the management of disseminated intravascular coagulation (DIC) is the treatment of the underlying condition triggering the coagulopathy. However, a number of uncertainties remain over the optimal supportive treatment. The aim of this study was to provide evidence and expert-based recommendations on the optimal supportive haemostatic and antithrombotic treatment strategies for patients with DIC. A working group defined five relevant clinical scenarios. Published studies were systematically searched in the MEDLINE and EMBASE databases (up to May 2014). Seven internationally recognised experts were asked to independently provide clinical advice. A two-phase blinded data collection technique was used to reach consensus. Only three randomised controlled trials (RCTs) on the supportive management of DIC were identified. The RCTs (overall less than 100 patients) investigated the use of fresh frozen plasma and platelet transfusion and found no differences in survival between the intervention and control groups. The experts' approach was heterogeneous, although there was consensus that supportive management should vary according to the underlying cause, clinical manifestations and severity of blood test abnormalities. Platelet transfusion should be given to maintain platelet count > 50×10⁹/l in case of bleeding while a lower threshold of 20 to 30×10⁹/l may be used in DIC without bleeding. Thromboprophylaxis with low-molecular-weight heparin is advised until bleeding ensues or platelet count drops below 30×10⁹/l. In conclusion, in the absence of solid evidence from RCTs, an individualised supportive management of DIC is advisable based on the type of underlying disease, presence of bleeding or thrombotic complications and laboratory tests results.

  15. Thromboelastometry in patients with severe sepsis and disseminated intravascular coagulation.

    PubMed

    Sivula, Mirka; Pettilä, Ville; Niemi, Tomi T; Varpula, Marjut; Kuitunen, Anne H

    2009-09-01

    Severe sepsis induces coagulopathy, which may lead to disseminated intravascular coagulation (DIC). Thromboelastometry is a point-of-care whole blood coagulation monitor, which has been validated in human endotoxemia model. We assessed thromboelastometry in severe sepsis and overt DIC and investigated its applicability in differentiating sepsis-related coagulation disturbances. Thromboelastometry (EXTEM and FIBTEM tests) and traditional coagulation assays were analyzed in 28 patients with severe sepsis, 12 of who fulfilled the criteria of overt DIC on admission. Ten healthy persons served as controls. Coagulation parameters, clotting time, clot formation time (CFT), alpha angle, maximal clot firmness (MCF) and lysis index at 60 min, were registered. In patients with overt DIC, EXTEM MCF, CFT and alpha angle differed from that in both healthy controls and patients without DIC, indicating hypocoagulation (MCF 52, 63 and 68 mm; CFT 184, 88 and 73 s; and alpha angle 58, 72 and 76 degrees , respectively, P < 0.01 for all). In patients without DIC, the trend was toward hypercoagulation in EXTEM and FIBTEM MCF (68 vs. 63 mm, P = 0.042 and 23 vs. 15 mm, P = 0.034, respectively). Receiver operating characteristic curves showed that MCF, CFT and alpha angle discriminated patients with overt DIC moderately (area under curve 0.891, 0.815 and 0.828, respectively, P < 0.001 for all). Traditional coagulation assays showed progressively worsening coagulopathy from controls to septic patients without DIC and further to those with overt DIC. We conclude that thromboelastometry may be a valuable tool in assessing whole blood coagulation capacity in patients with severe sepsis with and without overt DIC.

  16. Protection against high intravascular pressure in giraffe legs.

    PubMed

    Petersen, Karin K; Hørlyck, Arne; Ostergaard, Kristine H; Andresen, Joergen; Broegger, Torbjoern; Skovgaard, Nini; Telinius, Niklas; Laher, Ismael; Bertelsen, Mads F; Grøndahl, Carsten; Smerup, Morten; Secher, Niels H; Brøndum, Emil; Hasenkam, John M; Wang, Tobias; Baandrup, Ulrik; Aalkjaer, Christian

    2013-11-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along the artery. Histology of the isolated median artery confirmed dense sympathetic innervation at the narrowing. Structure and contractility of small arteries from muscular beds in the leg and neck were compared. The arteries from the legs demonstrated an increased media thickness-to-lumen diameter ratio, increased media volume, and increased numbers of smooth muscle cells per segment length and furthermore, they contracted more strongly than arteries from the neck (500 ± 49 vs. 318 ± 43 mmHg; n = 6 legs and neck, respectively). Finally, the transient increase in interstitial fluid pressure following injection of saline was 5.5 ± 1.7 times larger (n = 8) in the leg than in the neck. We conclude that 1) tissue compliance in the legs is low; 2) large arteries of the legs function as resistance arteries; and 3) structural adaptation of small muscle arteries allows them to develop an extraordinary tension. All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure. PMID:24005251

  17. Monte Carlo radiation dose simulations and dosimetric comparison of the model 6711 and 9011 {sup 125}I brachytherapy sources

    SciTech Connect

    Rivard, Mark J.

    2009-02-15

    Smaller diameter brachytherapy seeds for permanent interstitial implantation allow for use of smaller diameter implant needles. The use of smaller diameter needles may provide a lower incidence of healthy-tissue complications. This study determines the brachytherapy dosimetry parameters for the smaller diameter source (model 9011) and comments on the dosimetric comparison between this new source and the conventional brachytherapy seed (model 6711).

  18. Dosimetric analysis and comparison of IMRT and HDR brachytherapy in treatment of localized prostate cancer.

    PubMed

    Murali, V; Kurup, P G G; Mahadev, P; Mahalakshmi, S

    2010-04-01

    Radical radiotherapy is one of the options for the management of prostate cancer. In external beam therapy, 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) are the options for delivery of increased radiation dose, as vital organs are very close to the prostate and a higher dose to these structures leads to an increased toxicity. In brachytherapy, low dose rate brachytherapy with permanent implant of radioactive seeds and high dose rate brachytherapy (HDR) with remote after loaders are available. A dosimetric analysis has been made on IMRT and HDR brachytherapy plans. Ten cases from each IMRT and HDR brachytherapy have been taken for the study. The analysis includes comparison of conformity and homogeneity indices, D100, D95, D90, D80, D50, D10 and D5 of the target. For the organs at risk (OAR), namely rectum and bladder, V100, V90 and V50 are compared. In HDR brachytherapy, the doses to 1 cc and 0.1 cc of urethra have also been studied. Since a very high dose surrounds the source, the 300% dose volumes in the target and within the catheters are also studied in two plans, to estimate the actual volume of target receiving dose over 300%. This study shows that the prescribed dose covers 93 and 92% of the target volume in IMRT and HDR brachytherapy respectively. HDR brachytherapy delivers a much lesser dose to OAR, compared to the IMRT. For rectum, the V50 in IMRT is 34.0cc whilst it is 7.5cc in HDR brachytherapy. With the graphic optimization tool in HDR brachytherapy planning, the dose to urethra could be kept within 120% of the target dose. Hence it is concluded that HDR brachytherapy may be the choice of treatment for cancer of prostate in the early stage.

  19. Trends in the Utilization of Brachytherapy in Cervical Cancer in the United States

    SciTech Connect

    Han, Kathy; Milosevic, Michael; Fyles, Anthony; Pintilie, Melania; Viswanathan, Akila N.

    2013-09-01

    Purpose: To determine the trends in brachytherapy use in cervical cancer in the United States and to identify factors and survival benefits associated with brachytherapy treatment. Methods and Materials: Using the Surveillance, Epidemiology, and End Results (SEER) database, we identified 7359 patients with stages IB2-IVA cervical cancer treated with external beam radiation therapy (EBRT) between 1988 and 2009. Propensity score matching was used to adjust for differences between patients who received brachytherapy and those who did not from 2000 onward (after the National Cancer Institute alert recommending concurrent chemotherapy). Results: Sixty-three percent of the 7359 women received brachytherapy in combination with EBRT, and 37% received EBRT alone. The brachytherapy utilization rate has decreased from 83% in 1988 to 58% in 2009 (P<.001), with a sharp decline of 23% in 2003 to 43%. Factors associated with higher odds of brachytherapy use include younger age, married (vs single) patients, earlier years of diagnosis, earlier stage and certain SEER regions. In the propensity score-matched cohort, brachytherapy treatment was associated with higher 4-year cause-specific survival (CSS; 64.3% vs 51.5%, P<.001) and overall survival (OS; 58.2% vs 46.2%, P<.001). Brachytherapy treatment was independently associated with better CSS (hazard ratio [HR], 0.64; 95% confidence interval [CI], 0.57-0.71), and OS (HR 0.66; 95% CI, 0.60 to 0.74). Conclusions: This population-based analysis reveals a concerning decline in brachytherapy utilization and significant geographic disparities in the delivery of brachytherapy in the United States. Brachytherapy use is independently associated with significantly higher CSS and OS and should be implemented in all feasible cases.

  20. Dosimetric analysis and comparison of IMRT and HDR brachytherapy in treatment of localized prostate cancer

    PubMed Central

    Murali, V.; Kurup, P. G. G.; Mahadev, P.; Mahalakshmi, S.

    2010-01-01

    Radical radiotherapy is one of the options for the management of prostate cancer. In external beam therapy, 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) are the options for delivery of increased radiation dose, as vital organs are very close to the prostate and a higher dose to these structures leads to an increased toxicity. In brachytherapy, low dose rate brachytherapy with permanent implant of radioactive seeds and high dose rate brachytherapy (HDR) with remote after loaders are available. A dosimetric analysis has been made on IMRT and HDR brachytherapy plans. Ten cases from each IMRT and HDR brachytherapy have been taken for the study. The analysis includes comparison of conformity and homogeneity indices, D100, D95, D90, D80, D50, D10 and D5 of the target. For the organs at risk (OAR), namely rectum and bladder, V100, V90 and V50 are compared. In HDR brachytherapy, the doses to 1 cc and 0.1 cc of urethra have also been studied. Since a very high dose surrounds the source, the 300% dose volumes in the target and within the catheters are also studied in two plans, to estimate the actual volume of target receiving dose over 300%. This study shows that the prescribed dose covers 93 and 92% of the target volume in IMRT and HDR brachytherapy respectively. HDR brachytherapy delivers a much lesser dose to OAR, compared to the IMRT. For rectum, the V50 in IMRT is 34.0cc whilst it is 7.5cc in HDR brachytherapy. With the graphic optimization tool in HDR brachytherapy planning, the dose to urethra could be kept within 120% of the target dose. Hence it is concluded that HDR brachytherapy may be the choice of treatment for cancer of prostate in the early stage. PMID:20589121

  1. High-sensitivity intravascular photoacoustic imaging of lipid–laden plaque with a collinear catheter design

    PubMed Central

    Cao, Yingchun; Hui, Jie; Kole, Ayeeshik; Wang, Pu; Yu, Qianhuan; Chen, Weibiao; Sturek, Michael; Cheng, Ji-Xin

    2016-01-01

    A highly sensitive catheter probe is critical to catheter-based intravascular photoacoustic imaging. Here, we present a photoacoustic catheter probe design on the basis of collinear alignment of the incident optical wave and the photoacoustically generated sound wave within a miniature catheter housing for the first time. Such collinear catheter design with an outer diameter of 1.6 mm provided highly efficient overlap between optical and acoustic waves over an imaging depth of >6 mm in D2O medium. Intravascular photoacoustic imaging of lipid-laden atherosclerotic plaque and perivascular fat was demonstrated, where a lab-built 500 Hz optical parametric oscillator outputting nanosecond optical pulses at a wavelength of 1.7 μm was used for overtone excitation of C-H bonds. In addition to intravascular imaging, the presented catheter design will benefit other photoacoustic applications such as needle-based intramuscular imaging. PMID:27121894

  2. High-sensitivity intravascular photoacoustic imaging of lipid-laden plaque with a collinear catheter design.

    PubMed

    Cao, Yingchun; Hui, Jie; Kole, Ayeeshik; Wang, Pu; Yu, Qianhuan; Chen, Weibiao; Sturek, Michael; Cheng, Ji-Xin

    2016-01-01

    A highly sensitive catheter probe is critical to catheter-based intravascular photoacoustic imaging. Here, we present a photoacoustic catheter probe design on the basis of collinear alignment of the incident optical wave and the photoacoustically generated sound wave within a miniature catheter housing for the first time. Such collinear catheter design with an outer diameter of 1.6 mm provided highly efficient overlap between optical and acoustic waves over an imaging depth of >6 mm in D2O medium. Intravascular photoacoustic imaging of lipid-laden atherosclerotic plaque and perivascular fat was demonstrated, where a lab-built 500 Hz optical parametric oscillator outputting nanosecond optical pulses at a wavelength of 1.7 μm was used for overtone excitation of C-H bonds. In addition to intravascular imaging, the presented catheter design will benefit other photoacoustic applications such as needle-based intramuscular imaging. PMID:27121894

  3. Changes in morphology and permeability of perfused rabbit arteries during acute elevation of the intravascular pressure

    SciTech Connect

    Voino-Yasenetskaya, T.A.; Skuratovskaya, L.N.

    1986-12-01

    This paper presents a study on whether a short-term increase of intravascular pressure causes morphological injuries to the endothelium or accelerates the accumulation of /sup 125/I-labeled low-density lipoproteins (/sup 125/I-LDL) in the wall of perfused arteries of healthy rabbits, and how a raised hydrostatic pressure affects /sup 125/I-LDL transport in denuded areas of perfused arteries. The average number of cells per 1 mm/sup 2/ of luminal surface during perfusion under a pressure of 100-250 mm Hg is shown. Also, the morphology of endothelial lining of rabbit aorta under increased intravascular pressure is presented, as is the incorporation of /sup 125/I-LDL into wall of rabbit aorta under increased intravascular pressure.

  4. Chronic biliary obstruction induces pulmonary intravascular phagocytosis and endotoxin sensitivity in rats.

    PubMed Central

    Chang, S W; Ohara, N

    1994-01-01

    Endotoxin sensitivity varies among animal species and appears to correlate with the presence of pulmonary intravascular macrophage (PIM). In rats, which lack PIM, we investigated the hypothesis that chronic cholestatic liver injury leads to induction of PIM and endotoxin sensitivity. Rats were randomized to either common bile duct ligation (BDL) or sham-surgery and studied at 1 wk (acute cholestasis), 2 wk (cholestasis, early cirrhosis), and 4 wk (cholestasis, established cirrhosis) after surgery. Intravascularly injected fluorescent latex microspheres (1 micron diameter) were taken up by large phagocytic cells in lung parenchyma of BDL rats (at 2 and 4 wk), while no uptake was observed in lungs from control rats. Electronmicroscopy revealed accumulation of large, mononuclear, macrophage-like cells containing ingested latex particles within the pulmonary capillaries. Pulmonary intravascular phagocytosis, as reflected in lung uptake of 99mTc microaggregated albumin (Microlite, mean particle diameter = 1 micron), averaged 0.7 +/- 0.1% (mean +/- SEM) of total injected dose in 13 control rats and progressively increased with time after BDL (1 wk, 1.7 +/- 0.2%; 2 wk, 10.0 +/- 3.0%; 4 wk 35.1 +/- 5.9%). Rats with biliary cirrhosis were markedly sensitive to the lethal effects of low dose endotoxin and demonstrated marked lung edema at the time of death. Furthermore, the lung uptake of intravascular 125I-lipopolysaccharide was increased five-fold in cirrhotic rats. We conclude that chronic biliary obstruction leads to the induction of pulmonary intravascular phagocytes and enhances endotoxin sensitivity in rats. Pulmonary intravascular phagocytosis in patients with advanced cirrhosis may account for their increased susceptibility to sepsis-induced adult respiratory distress syndrome. Images PMID:7962547

  5. Review of advanced catheter technologies in radiation oncology brachytherapy procedures

    PubMed Central

    Zhou, Jun; Zamdborg, Leonid; Sebastian, Evelyn

    2015-01-01

    The development of new catheter and applicator technologies in recent years has significantly improved treatment accuracy, efficiency, and outcomes in brachytherapy. In this paper, we review these advances, focusing on the performance of catheter imaging and reconstruction techniques in brachytherapy procedures using magnetic resonance images and electromagnetic tracking. The accuracy of catheter reconstruction, imaging artifacts, and other notable properties of plastic and titanium applicators in gynecologic treatments are reviewed. The accuracy, noise performance, and limitations of electromagnetic tracking for catheter reconstruction are discussed. Several newly developed applicators for accelerated partial breast irradiation and gynecologic treatments are also reviewed. New hypofractionated high dose rate treatment schemes in prostate cancer and accelerated partial breast irradiation are presented. PMID:26203277

  6. Metal artefacts in MRI-guided brachytherapy of cervical cancer

    PubMed Central

    Owrangi, Amir; Ravi, Ananth; Song, William Y.

    2016-01-01

    The importance of assessing the metal-induced artefacts in magnetic resonance imaging (MRI)-guided brachytherapy is growing along with the increasing interest of integrating MRI into the treatment procedure of cervical cancer. Examples of metal objects in use include intracavitary cervical applicators and interstitial needles. The induced artefacts increase the uncertainties in the clinical workflow and can be a potential obstacle for the accurate delivery of the treatment. Overcoming this problem necessitates a good understanding of its originating sources. Several efforts are recorded in the literature to quantify the extent of such artefacts, in phantoms and in clinical practice. Here, we elaborate on the origin of metal-induced artefacts in the light of brachytherapy applications, while summarizing recent efforts that have been made to assess and overcome the induced distortions.

  7. Cataract extraction after brachytherapy for malignant melanoma of the choroid

    SciTech Connect

    Fish, G.E.; Jost, B.F.; Snyder, W.I.; Fuller, D.G.; Birch, D.G. )

    1991-05-01

    Thirteen eyes of 55 consecutive patients treated with brachytherapy for malignant melanoma of the choroid developed postirradiation cataracts. Cataract development was more common in older patients and in patients with larger and more anterior tumors. Eleven eyes had extracapsular cataract extraction and intraocular lens implantation. Initial visual improvement occurred in 91% of eyes, with an average improvement of 5.5 lines. Visual acuity was maintained at 20/60 or better in 55% of the eyes over an average period of follow-up of 24 months (range, 6 to 40 months). These data suggest that, visually, cataract extraction can be helpful in selected patients who develop a cataract after brachytherapy for malignant melanoma of the choroid.

  8. [Basic principles and results of brachytherapy in gynecological oncology].

    PubMed

    Kanaev, S V; Turkevich, V G; Baranov, S B; Savel'eva, V V

    2014-01-01

    The fundamental basics of contact radiation therapy (brachytherapy) for gynecological cancer are presented. During brachytherapy the principles of conformal radiotherapy should be implemented, the aim of which is to sum the maximum possible dose of radiation to the tumor and decrease the dose load in adjacent organs and tissues, which allows reducing the frequency of radiation damage at treatment of primary tumors. It is really feasible only on modern technological level, thanks to precision topometry preparation, optimal computer dosimetrical and radiobiological planning of each session and radiotherapy in general. Successful local and long-term results of the contact radiation therapy for cancer of cervix and endometrium are due to optimal anatomical and topometrical ratio of the tumor localization, radioactive sources, and also physical and radiobiological laws of distribution and effects of ionizing radiation, the dose load accounting rules.

  9. Distortions induced by radioactive seeds into interstitial brachytherapy dose distributions.

    PubMed

    Zhou, Chuanyu; Inanc, Feyzi; Modrick, Joseph M

    2004-12-01

    In a previous article, we presented development and verification of an integral transport equation-based deterministic algorithm for computing three-dimensional brachytherapy dose distributions. Recently, we have included fluorescence radiation physics and parallel computation to the standing algorithms so that we can compute dose distributions for a large set of seeds without resorting to the superposition methods. The introduction of parallel computing capability provided a means to compute the dose distribution for multiple seeds in a simultaneous manner. This provided a way to study strong heterogeneity and shadow effects induced by the presence of multiple seeds in an interstitial brachytherapy implant. This article presents the algorithm for computing fluorescence radiation, algorithm for parallel computing, and display results for an 81-seed implant that has a perfect and imperfect lattice. The dosimetry data for a single model 6711 seeds is presented for verification and heterogeneity factor computations using simultaneous and superposition techniques are presented.

  10. Metal artefacts in MRI-guided brachytherapy of cervical cancer.

    PubMed

    Soliman, Abraam S; Owrangi, Amir; Ravi, Ananth; Song, William Y

    2016-08-01

    The importance of assessing the metal-induced artefacts in magnetic resonance imaging (MRI)-guided brachytherapy is growing along with the increasing interest of integrating MRI into the treatment procedure of cervical cancer. Examples of metal objects in use include intracavitary cervical applicators and interstitial needles. The induced artefacts increase the uncertainties in the clinical workflow and can be a potential obstacle for the accurate delivery of the treatment. Overcoming this problem necessitates a good understanding of its originating sources. Several efforts are recorded in the literature to quantify the extent of such artefacts, in phantoms and in clinical practice. Here, we elaborate on the origin of metal-induced artefacts in the light of brachytherapy applications, while summarizing recent efforts that have been made to assess and overcome the induced distortions. PMID:27648092

  11. Intraoperative interstitial microwave-induced hyperthermia and brachytherapy.

    PubMed

    Coughlin, C T; Wong, T Z; Strohbehn, J W; Colacchio, T A; Sutton, J E; Belch, R Z; Douple, E B

    1985-09-01

    Intra-operative placement of 11-gauge nylon catheters into deep-seated unresectable tumors for interstitial brachytherapy permits localized heating of tumors (hyperthermia) using microwave (915 MHz) antennas which are inserted into these catheters. Four preliminary cases are described where epithelial tumors at various sites were implanted with an antenna array and heated for 1 hour, both before and after the iridium-192 brachytherapy. Temperatures were monitored in catheters required for the appropriate radiation dosimetry but not required for the interstitial microwave antenna array hyperthermia (IMAAH) system. Additional thermometry was obtained using nonperturbed fiberoptic thermometry probes inserted into the catheters' housing antennas. No significant complications, such as bleeding or infection, were observed. This approach to cancer therapy is shown to be feasible and it produces controlled, localized hyperthermia, with temperatures of 50 degrees C or more in tumors. This technique may offer a therapeutic option for pelvic, intra-abdominal and head and neck tumors.

  12. Metal artefacts in MRI-guided brachytherapy of cervical cancer

    PubMed Central

    Owrangi, Amir; Ravi, Ananth; Song, William Y.

    2016-01-01

    The importance of assessing the metal-induced artefacts in magnetic resonance imaging (MRI)-guided brachytherapy is growing along with the increasing interest of integrating MRI into the treatment procedure of cervical cancer. Examples of metal objects in use include intracavitary cervical applicators and interstitial needles. The induced artefacts increase the uncertainties in the clinical workflow and can be a potential obstacle for the accurate delivery of the treatment. Overcoming this problem necessitates a good understanding of its originating sources. Several efforts are recorded in the literature to quantify the extent of such artefacts, in phantoms and in clinical practice. Here, we elaborate on the origin of metal-induced artefacts in the light of brachytherapy applications, while summarizing recent efforts that have been made to assess and overcome the induced distortions. PMID:27648092

  13. Metal artefacts in MRI-guided brachytherapy of cervical cancer.

    PubMed

    Soliman, Abraam S; Owrangi, Amir; Ravi, Ananth; Song, William Y

    2016-08-01

    The importance of assessing the metal-induced artefacts in magnetic resonance imaging (MRI)-guided brachytherapy is growing along with the increasing interest of integrating MRI into the treatment procedure of cervical cancer. Examples of metal objects in use include intracavitary cervical applicators and interstitial needles. The induced artefacts increase the uncertainties in the clinical workflow and can be a potential obstacle for the accurate delivery of the treatment. Overcoming this problem necessitates a good understanding of its originating sources. Several efforts are recorded in the literature to quantify the extent of such artefacts, in phantoms and in clinical practice. Here, we elaborate on the origin of metal-induced artefacts in the light of brachytherapy applications, while summarizing recent efforts that have been made to assess and overcome the induced distortions.

  14. Compound dual radiation action theory for 252Cf brachytherapy.

    PubMed

    Wang, C K; Zhang, X

    2004-01-01

    The existing dosimetry protocol that uses the concept of RBE for 252Cf brachytherapy contains large uncertainties. A new formula has been developed to correlate the biological effect (i.e. cell survival fraction) resulting from a mixed n + gamma radiation field with two physical quantities and two biological quantities. The formula is based on a pathway model evolved from that of the compound-dual-radiation-action (CDRA) theory, previously proposed by Rossi and Zaider. The new model employs the recently published data on radiation-induced DNA lesions. The new formula is capable of predicting quantitatively the synergistic effect caused by the interactions between neutron events and gamma ray events, and it is intended to be included into a new dosimetry protocol for future 252Cf brachytherapy.

  15. High dose rate (HDR) brachytherapy quality assurance: a practical guide

    PubMed Central

    Wilkinson, DA

    2006-01-01

    The widespread adoption of high dose rate brachytherapy with its inherent dangers necessitates adoption of appropriate quality assurance measures to minimize risks to both patients and medical staff. This paper is aimed at assisting someone who is establishing a new program or revising one already in place into adhere to the recently issued Nuclear Regulatory Commission (USA) regulations and the guidelines from the American Association of Physicists in Medicine. PMID:21614233

  16. Brachytherapy in Lip Carcinoma: Long-Term Results

    SciTech Connect

    Guibert, Mireille; David, Isabelle; Vergez, Sebastien; Rives, Michel; Filleron, Thomas; Bonnet, Jacques; Delannes, Martine

    2011-12-01

    Purpose: The aim of this study was to evaluate the effectiveness of low-dose-rate brachytherapy for local control and relapse-free survival in squamous cell and basal cell carcinomas of the lips. We compared two groups: one with tumors on the skin and the other with tumors on the lip. Patients and methods: All patients had been treated at Claudius Regaud Cancer Centre from 1990 to 2008 for squamous cell or basal cell carcinoma. Low-dose-rate brachytherapy was performed with iridium 192 wires according to the Paris system rules. On average, the dose delivered was 65 Gy. Results: 172 consecutive patients were included in our study; 69 had skin carcinoma (squamous cell or basal cell), and 92 had squamous cell mucosal carcinoma. The average follow-up time was 5.4 years. In the skin cancer group, there were five local recurrences and one lymph node recurrence. In the mucosal cancer group, there were ten local recurrences and five lymph node recurrences. The 8-year relapse-free survival for the entire population was 80%. The 8-year relapse-free survival was 85% for skin carcinoma 75% for mucosal carcinoma, with no significant difference between groups. The functional results were satisfactory for 99% of patients, and the cosmetic results were satisfactory for 92%. Maximal toxicity observed was Grade 2. Conclusions: Low-dose-rate brachytherapy can be used to treat lip carcinomas at Stages T1 and T2 as the only treatment with excellent results for local control and relapse-free survival. The benefits of brachytherapy are also cosmetic and functional, with 91% of patients having no side effects.

  17. Californium-252 brachytherapy for anal and ano-rectal carcinoma

    SciTech Connect

    Cross, B.; Maruyama, Y.; Proudfoot, W.; Malcolm, A.

    1986-01-01

    Surgery has historically been the standard treatment for anal, ano-rectal and rectal carcinoma but is prone to local or regional failure. Over the past 15 years there has been increasing interest in and success with radiation therapy and combined chemoradiotherapy for treatment of anal and ano-rectal cancers. Cf-252 brachytherapy combined with external beam teletherapy has been investigated for anal and ano-rectal lesions at the Univ. of Kentucky with encouraging results.

  18. Serum Testosterone Kinetics After Brachytherapy for Clinically Localized Prostate Cancer

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan H.; Allen, Zachariah A.; Wallner, Kent E.

    2012-01-01

    Purpose: To evaluate temporal changes in testosterone after prostate brachytherapy and investigate the potential impact of these changes on response to treatment. Methods and Materials: Between January 2008 and March 2009, 221 consecutive patients underwent Pd-103 brachytherapy without androgen deprivation for clinically localized prostate cancer. Prebrachytherapy prostate-specific antigen (PSA) and serum testosterone were obtained for each patient. Repeat levels were obtained 3 months after brachytherapy and at least every 6 months thereafter. Multiple clinical, treatment, and dosimetric parameters were evaluated to determine an association with temporal testosterone changes. In addition, analysis was conducted to determine if there was an association between testosterone changes and treatment outcomes or the occurrence of a PSA spike. Results: There was no significant difference in serum testosterone over time after implant (p = 0.57). 29% of men experienced an increase {>=}25%, 23% of men experienced a decrease {>=}25%, and the remaining 48% of men had no notable change in testosterone over time. There was no difference in testosterone trends between men who received external beam radiotherapy and those who did not (p = 0.12). On multivariate analysis, preimplant testosterone was the only variable that consistently predicted for changes in testosterone over time. Men with higher than average testosterone tended to experience drop in testosterone (p < 0.001), whereas men with average or below average baseline testosterone had no significant change. There was no association between men who experienced PSA spike and testosterone temporal trends (p = 0.50) nor between initial PSA response and testosterone trends (p = 0.21). Conclusion: Prostate brachytherapy does not appear to impact serum testosterone over time. Changes in serum testosterone do not appear to be associated with PSA spike phenomena nor with initial PSA response to treatment; therefore, PSA response

  19. Cable attachment for a radioactive brachytherapy source capsule

    DOEpatents

    Gross, Ian G; Pierce, Larry A

    2006-07-18

    In cancer brachytherapy treatment, a small californium-252 neutron source capsule is attached to a guide cable using a modified crimping technique. The guide cable has a solid cylindrical end, and the attachment employs circumferential grooves micromachined in the solid cable end. The attachment was designed and tested, and hardware fabricated for use inside a radioactive hot cell. A welding step typically required in other cable attachments is avoided.

  20. Leiomyosarcoma of the Uterus with Intravascular Tumor Extension and Pulmonary Tumor Embolism

    SciTech Connect

    McDonald, Douglas K.; Kalva, Sanjeeva P. Fan, C.-M.; Vasilyev, Aleksandr

    2007-02-15

    We report the case of a 48-year-old woman presenting with recurrent uterine leiomyosarcoma (LMS) associated with right iliac vein and inferior vena cava (IVC) invasion and left lower lobe pulmonary tumor embolus. Because the prognosis and treatment differ from that of thrombotic pulmonary emboli, the differentiating imaging characteristics of intravascular tumor embolism are reviewed. To our knowledge, only two other cases of intravenous uterine leiomyosarcomatosis have been described in the existing literature, and this is the first reported case of the entity with associated intravascular tumor embolism.

  1. Study of dose calculation on breast brachytherapy using prism TPS

    NASA Astrophysics Data System (ADS)

    Fendriani, Yoza; Haryanto, Freddy

    2015-09-01

    PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm3. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm3. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy.

  2. Implicit active contours for automatic brachytherapy seed segmentation in fluoroscopy

    NASA Astrophysics Data System (ADS)

    Moult, Eric; Burdette, Clif; Song, Danny; Fichtinger, Gabor; Fallavollita, Pascal

    2012-02-01

    Motivation: In prostate brachytherapy, intra-operative dosimetry would be ideal to allow for rapid evaluation of the implant quality while the patient is still in the treatment position. Such a mechanism, however, requires 3-D visualization of the currently deposited seeds relative to the prostate. Thus, accurate, robust, and fully-automatic seed segmentation is of critical importance in achieving intra-operative dosimetry. Methodology: Implanted brachytherapy seeds are segmented by utilizing a region-based implicit active contour approach. Overlapping seed clusters are then resolved using a simple yet effective declustering technique. Results: Ground-truth seed coordinates were obtained via a published segmentation technique. A total of 248 clinical C-arm images from 16 patients were used to validate the proposed algorithm resulting in a 98.4% automatic detection rate with a corresponding 2.5% false-positive rate. The overall mean centroid error between the ground-truth and automatic segmentations was measured to be 0.42 pixels, while the mean centroid error for overlapping seed clusters alone was measured to be 0.67 pixels. Conclusion: Based on clinical data evaluation and validation, robust, accurate, and fully-automatic brachytherapy seed segmentation can be achieved through the implicit active contour framework and subsequent seed declustering method.

  3. Accelerated partial breast irradiation utilizing brachytherapy: patient selection and workflow.

    PubMed

    Shah, Chirag; Wobb, Jessica; Manyam, Bindu; Khan, Atif; Vicini, Frank

    2016-02-01

    Accelerated partial breast irradiation (APBI) represents an evolving technique that is a standard of care option in appropriately selected woman following breast conserving surgery. While multiple techniques now exist to deliver APBI, interstitial brachytherapy represents the technique used in several randomized trials (National Institute of Oncology, GEC-ESTRO). More recently, many centers have adopted applicator-based brachytherapy to deliver APBI due to the technical complexities of interstitial brachytherapy. The purpose of this article is to review methods to evaluate and select patients for APBI, as well as to define potential workflow mechanisms that allow for the safe and effective delivery of APBI. Multiple consensus statements have been developed to guide clinicians on determining appropriate candidates for APBI. However, recent studies have demonstrated that these guidelines fail to stratify patients according to the risk of local recurrence, and updated guidelines are expected in the years to come. Critical elements of workflow to ensure safe and effective delivery of APBI include a multidisciplinary approach and evaluation, optimization of target coverage and adherence to normal tissue guideline constraints, and proper quality assurance methods. PMID:26985202

  4. A compilation of current regulations, standards and guidelines in remote afterloading brachytherapy

    SciTech Connect

    Tortorelli, J.P.; Simion, G.P.; Kozlowski, S.D.

    1994-10-01

    Over a dozen government and professional organizations in the United States and Europe have issued regulations and guidance concerning quality management in the practice of remote afterloading brachytherapy. Information from the publications of these organizations was collected and collated for this report. This report provides the brachytherapy licensee access to a broad field of quality management information in a single, topically organized document.

  5. Report of a consensus meeting on focal low dose rate brachytherapy for prostate cancer.

    PubMed

    Langley, Stephen; Ahmed, Hashim U; Al-Qaisieh, Bashar; Bostwick, David; Dickinson, Louise; Veiga, Francisco Gomez; Grimm, Peter; Machtens, Stefan; Guedea, Ferran; Emberton, Mark

    2012-02-01

    What's known on the subject? and What does the study add? Whole gland brachytherapy has been used to successfully treat prostate cancer but the protocol for focal therapy has not previously been established. The consensus findings provide guidance on patient selection for focal brachytherapy as well as recommendations for conducting therapy and patient follow-up. Low dose rate prostate brachytherapy is an effective treatment for localized prostate cancer. Recently, it has been considered for use in a focused manner whereby treatment is targeted only to areas of prostate cancer. The objective of focal brachytherapy is to provide effective cancer control for low-risk disease but with reduced genitourinary and rectal side-effects in a cost-effective way. We report on the outputs of a consensus meeting of international experts in brachytherapy and focal therapy convened to consider the feasibility and potential development of focal brachytherapy. A number of factors were considered for focal brachytherapy including optimal patient selection, disease characterization and localization, treatment protocols and outcome measures. The consensus meeting also addressed the design of a clinical trial that would assess the oncological outcomes and side-effect profiles resulting from focal brachytherapy. PMID:22239224

  6. [Brachytherapy in France: current situation and economic outlook due to the unavailability of iridium wires].

    PubMed

    Le Vu, B; Boucher, S

    2014-10-01

    In 2013, about 6000 patients were treated with brachytherapy, the number diminishing by 2.6% per year since 2008. Prostate, breast and gynecological cancers are the most common types of cancers. Since 2008, the number of brachytherapy facilities has decreased by 18%. In medicoeconomic terms, brachytherapy faces many problems: the coding system is outdated; brachytherapy treatments cost as much as internal radiation; fees do not cover costs; since iridium wire has disappeared from the market, the technique will be transferred to more expensive high-speed or pulse dose rates. The French financing grid based on the national study of costs lags behind changes in such treatments and in the best of cases, hospitals resorting to alternatives such as in-hospital brachytherapy are funded at 46% of their additional costs. Brachytherapy is a reference technique. With intense pressure on hospital pricing, financing brachytherapy facilities will become even more problematic as a consequence of the disappearance of iridium 192 wires. The case of brachytherapy illustrates the limits of the French financing system and raises serious doubts as to its responsiveness. PMID:25195115

  7. IMPACT OF OBESITY ON ENDOTOXIN-INDUCED DISSEMINATED INTRAVASCULAR COAGULATION.

    PubMed

    Duburcq, Thibault; Tournoys, Antoine; Gnemmi, Viviane; Hubert, Thomas; Gmyr, Valery; Pattou, François; Jourdain, Mercé

    2015-10-01

    An early activation of coagulation and fibrinolysis occurs during sepsis, leading to the syndrome of disseminated intravascular coagulation (DIC). Obesity has been demonstrated to be a hypercoagulable and hypofibrinolytic state, but its impact on DIC has never been studied. In this study, we aimed to determine if obesity impairs DIC in an acute endotoxic shock model using minipigs. This was a prospective, comparative, and experimental ancillary study approved by the Animal Ethics Committee. Pigs were chosen as a clinically relevant species, resembling humans in coagulation reactions. Four groups of five "Yucatan" minipigs were studied: lean and obese control groups, a lean lipopolysaccharide (LPS) group receiving Escherichia coli endotoxin (LPS), and an obese LPS group receiving the same endotoxin dose. We measured standard coagulation parameters (prothrombin time [PT], platelet count, and fibrinogen levels), thrombin-antithrombin complexes, tissue-type plasminogen activator, and plasminogen activator inhibitor-1. All measurements were performed at baseline and 30, 60, 90, 150, and 300 min. Results were given as median with interquartile ranges. At baseline, platelet count (477 [428 - 532] G/L vs. 381 [307 - 442] G/L; P = 0.005) and fibrinogen levels (4.6 [3.8 - 5.2] g/L vs. 2 [1.8 - 2.9] g/L; P < 0.001) were significantly higher, whereas PT (80% [76% - 92%] vs. 96% [89% - 100%]; P = 0.01) was significantly lower in obese pigs compared with lean pigs. In the LPS groups, administration of endotoxin resulted in a typical hypokinetic shock with DIC. The decrease in coagulation parameters (PT, platelet count, and fibrinogen levels) and the increase in thrombin-antithrombin complexes (581 [382 - 1,057] μg/mL vs. 247 [125 - 369] μg/mL at 150 min; P = 0.03) were significantly more important in the obese LPS group compared with those in the lean LPS group. Concerning the fibrinolytic reaction, we found a slightly more elevated increase of plasminogen

  8. Meta-analysis on intravascular low energy laser therapy

    NASA Astrophysics Data System (ADS)

    Zhao, Shu-Dong; Liu, Timon Cheng-Yi; Wang, Yan-Fang; Liu, Song-Hao

    2008-12-01

    Intravascular low energy laser therapy (ILELT) was put forward for cardiocirculatory diseases in USA in 1982, was popular in Russia in 1980s, and then in China in 1990s. The therapeutic effects of ILELT and drugs in comparison with drugs only on Chinese patients and their blood parameters were analyzed with meta-analyses and reported as (OR, 95%CI) for patient improvement and (WMD, 95% CI) for blood parameter improvement, where 95%CI, OR and WMD denoted 95% confidence intervals, odds ratio and weighted mean difference, respectively. It was found that the patients of cerebral infarction (2.39, 2.09~2.74) and cerebrovascular diseases (2.97, 1.69~2.53) were cured, respectively, (P < 0.01), and the symptom improvement of patients of cerebral infarction, cerebrovascular diseases and diabetes were significant (3.13, 2.79~3.51), (4.92, 3.39~7.14) , and (3.80, 2.79~5.18), and mild (3.66, 3.15~4.24), (4.95, 2.77~8.84), and (7.11, 4.54~11.13), respectively, (P < 0.01). It was also found that the blood parameters such as cholesterol (-0.78, -1.32~-0.24), total cholesterol (-1.08, -1.80~-0.36), low density lipoprotein cholesterol (-0.6, -1.01~-0.19), triacylglycerol (0.63, -0.83~-0.42), high density lipoprotein (0.34, 0.10~0.59), erythrocyte aggregation index (-0.24, -0.27~-0.21), erythrocyte Sedimentation Rate (-4.57, -7.26~-1.89), fibrinogen (-0.76, -1.31~-0.21), whole blood contrast viscosity (-0.40, -0.69~-0.12), low cut blood viscosity (-1.2, -1.93~-0.48), high cut blood viscosity (-0.62, -0.92~-0.32), whole blood viscosity(-1.2, -1.85~-0.54) and plasma blood contrast viscosity(-0.07, -0.12~-0.03) were found improved (P < 0.05). It is concluded that the patients of cerebral infarction, cerebrovascular diseases and diabetes might be improved with ILELT, which might be mediated by blood parameter improvement.

  9. Novel treatment options for nonmelanoma skin cancer: focus on electronic brachytherapy.

    PubMed

    Kasper, Michael E; Chaudhary, Ahmed A

    2015-01-01

    Nonmelanoma skin cancer (NMSC) is an increasing health care issue in the United States, significantly affecting quality of life and impacting health care costs. Radiotherapy has a long history in the treatment of NMSC. Shortly after the discovery of X-rays and (226)Radium, physicians cured patients with NMSC using these new treatments. Both X-ray therapy and brachytherapy have evolved over the years, ultimately delivering higher cure rates and lower toxicity. Electronic brachytherapy for NMSC is based on the technical and clinical data obtained from radionuclide skin surface brachytherapy and the small skin surface applicators developed over the past 25 years. The purpose of this review is to introduce electronic brachytherapy in the context of the history, data, and utilization of traditional radiotherapy and brachytherapy.

  10. Air kerma and absorbed dose standards for reference dosimetry in brachytherapy

    PubMed Central

    2014-01-01

    This article reviews recent developments in primary standards for the calibration of brachytherapy sources, with an emphasis on the currently most common photon-emitting radionuclides. The introduction discusses the need for reference dosimetry in brachytherapy in general. The following section focuses on the three main quantities, i.e. reference air kerma rate, air kerma strength and absorbed dose rate to water, which are currently used for the specification of brachytherapy photon sources and which can be realized with primary standards from first principles. An overview of different air kerma and absorbed dose standards, which have been independently developed by various national metrology institutes over the past two decades, is given in the next two sections. Other dosimetry techniques for brachytherapy will also be discussed. The review closes with an outlook on a possible transition from air kerma to absorbed dose to water-based calibrations for brachytherapy sources in the future. PMID:24814696

  11. Novel treatment options for nonmelanoma skin cancer: focus on electronic brachytherapy.

    PubMed

    Kasper, Michael E; Chaudhary, Ahmed A

    2015-01-01

    Nonmelanoma skin cancer (NMSC) is an increasing health care issue in the United States, significantly affecting quality of life and impacting health care costs. Radiotherapy has a long history in the treatment of NMSC. Shortly after the discovery of X-rays and (226)Radium, physicians cured patients with NMSC using these new treatments. Both X-ray therapy and brachytherapy have evolved over the years, ultimately delivering higher cure rates and lower toxicity. Electronic brachytherapy for NMSC is based on the technical and clinical data obtained from radionuclide skin surface brachytherapy and the small skin surface applicators developed over the past 25 years. The purpose of this review is to introduce electronic brachytherapy in the context of the history, data, and utilization of traditional radiotherapy and brachytherapy. PMID:26648763

  12. Novel treatment options for nonmelanoma skin cancer: focus on electronic brachytherapy

    PubMed Central

    Kasper, Michael E; Chaudhary, Ahmed A

    2015-01-01

    Nonmelanoma skin cancer (NMSC) is an increasing health care issue in the United States, significantly affecting quality of life and impacting health care costs. Radiotherapy has a long history in the treatment of NMSC. Shortly after the discovery of X-rays and 226Radium, physicians cured patients with NMSC using these new treatments. Both X-ray therapy and brachytherapy have evolved over the years, ultimately delivering higher cure rates and lower toxicity. Electronic brachytherapy for NMSC is based on the technical and clinical data obtained from radionuclide skin surface brachytherapy and the small skin surface applicators developed over the past 25 years. The purpose of this review is to introduce electronic brachytherapy in the context of the history, data, and utilization of traditional radiotherapy and brachytherapy. PMID:26648763

  13. ALGEBRA: ALgorithm for the heterogeneous dosimetry based on GEANT4 for BRAchytherapy.

    PubMed

    Afsharpour, H; Landry, G; D'Amours, M; Enger, S; Reniers, B; Poon, E; Carrier, J-F; Verhaegen, F; Beaulieu, L

    2012-06-01

    Task group 43 (TG43)-based dosimetry algorithms are efficient for brachytherapy dose calculation in water. However, human tissues have chemical compositions and densities different than water. Moreover, the mutual shielding effect of seeds on each other (interseed attenuation) is neglected in the TG43-based dosimetry platforms. The scientific community has expressed the need for an accurate dosimetry platform in brachytherapy. The purpose of this paper is to present ALGEBRA, a Monte Carlo platform for dosimetry in brachytherapy which is sufficiently fast and accurate for clinical and research purposes. ALGEBRA is based on the GEANT4 Monte Carlo code and is capable of handling the DICOM RT standard to recreate a virtual model of the treated site. Here, the performance of ALGEBRA is presented for the special case of LDR brachytherapy in permanent prostate and breast seed implants. However, the algorithm is also capable of handling other treatments such as HDR brachytherapy.

  14. Dosimetry Modeling for Focal Low-Dose-Rate Prostate Brachytherapy

    SciTech Connect

    Al-Qaisieh, Bashar; Mason, Josh; Bownes, Peter; Henry, Ann; Dickinson, Louise; Ahmed, Hashim U.; Emberton, Mark; Langley, Stephen

    2015-07-15

    Purpose: Focal brachytherapy targeted to an individual lesion(s) within the prostate may reduce side effects experienced with whole-gland brachytherapy. The outcomes of a consensus meeting on focal prostate brachytherapy were used to investigate optimal dosimetry of focal low-dose-rate (LDR) prostate brachytherapy targeted using multiparametric magnetic resonance imaging (mp-MRI) and transperineal template prostate mapping (TPM) biopsy, including the effects of random and systematic seed displacements and interseed attenuation (ISA). Methods and Materials: Nine patients were selected according to clinical characteristics and concordance of TPM and mp-MRI. Retrospectively, 3 treatment plans were analyzed for each case: whole-gland (WG), hemi-gland (hemi), and ultra-focal (UF) plans, with 145-Gy prescription dose and identical dose constraints for each plan. Plan robustness to seed displacement and ISA were assessed using Monte Carlo simulations. Results: WG plans used a mean 28 needles and 81 seeds, hemi plans used 17 needles and 56 seeds, and UF plans used 12 needles and 25 seeds. Mean D90 (minimum dose received by 90% of the target) and V100 (percentage of the target that receives 100% dose) values were 181.3 Gy and 99.8% for the prostate in WG plans, 195.7 Gy and 97.8% for the hemi-prostate in hemi plans, and 218.3 Gy and 99.8% for the focal target in UF plans. Mean urethra D10 was 205.9 Gy, 191.4 Gy, and 92.4 Gy in WG, hemi, and UF plans, respectively. Mean rectum D2 cm{sup 3} was 107.5 Gy, 77.0 Gy, and 42.7 Gy in WG, hemi, and UF plans, respectively. Focal plans were more sensitive to seed displacement errors: random shifts with a standard deviation of 4 mm reduced mean target D90 by 14.0%, 20.5%, and 32.0% for WG, hemi, and UF plans, respectively. ISA has a similar impact on dose-volume histogram parameters for all plan types. Conclusions: Treatment planning for focal LDR brachytherapy is feasible. Dose constraints are easily met with a notable

  15. Third-party brachytherapy source calibrations and physicist responsibilities: Report of the AAPM Low Energy Brachytherapy Source Calibration Working Group

    SciTech Connect

    Butler, Wayne M.; Bice, William S. Jr.; DeWerd, Larry A.; Hevezi, James M.; Huq, M. Saiful; Ibbott, Geoffrey S.; Palta, Jatinder R.; Rivard, Mark J.; Seuntjens, Jan P.; Thomadsen, Bruce R.

    2008-09-15

    The AAPM Low Energy Brachytherapy Source Calibration Working Group was formed to investigate and recommend quality control and quality assurance procedures for brachytherapy sources prior to clinical use. Compiling and clarifying recommendations established by previous AAPM Task Groups 40, 56, and 64 were among the working group's charges, which also included the role of third-party handlers to perform loading and assay of sources. This document presents the findings of the working group on the responsibilities of the institutional medical physicist and a clarification of the existing AAPM recommendations in the assay of brachytherapy sources. Responsibility for the performance and attestation of source assays rests with the institutional medical physicist, who must use calibration equipment appropriate for each source type used at the institution. Such equipment and calibration procedures shall ensure secondary traceability to a national standard. For each multi-source implant, 10% of the sources or ten sources, whichever is greater, are to be assayed. Procedures for presterilized source packaging are outlined. The mean source strength of the assayed sources must agree with the manufacturer's stated strength to within 3%, or action must be taken to resolve the difference. Third party assays do not absolve the institutional physicist from the responsibility to perform the institutional measurement and attest to the strength of the implanted sources. The AAPM leaves it to the discretion of the institutional medical physicist whether the manufacturer's or institutional physicist's measured value should be used in performing dosimetry calculations.

  16. Third-party brachytherapy source calibrations and physicist responsibilities: report of the AAPM Low Energy Brachytherapy Source Calibration Working Group.

    PubMed

    Butler, Wayne M; Bice, William S; DeWerd, Larry A; Hevezi, James M; Huq, M Saiful; Ibbott, Geoffrey S; Palta, Jatinder R; Rivard, Mark J; Seuntjens, Jan P; Thomadsen, Bruce R

    2008-09-01

    The AAPM Low Energy Brachytherapy Source Calibration Working Group was formed to investigate and recommend quality control and quality assurance procedures for brachytherapy sources prior to clinical use. Compiling and clarifying recommendations established by previous AAPM Task Groups 40, 56, and 64 were among the working group's charges, which also included the role of third-party handlers to perform loading and assay of sources. This document presents the findings of the working group on the responsibilities of the institutional medical physicist and a clarification of the existing AAPM recommendations in the assay of brachytherapy sources. Responsibility for the performance and attestation of source assays rests with the institutional medical physicist, who must use calibration equipment appropriate for each source type used at the institution. Such equipment and calibration procedures shall ensure secondary traceability to a national standard. For each multi-source implant, 10% of the sources or ten sources, whichever is greater, are to be assayed. Procedures for presterilized source packaging are outlined. The mean source strength of the assayed sources must agree with the manufacturer's stated strength to within 3%, or action must be taken to resolve the difference. Third party assays do not absolve the institutional physicist from the responsibility to perform the institutional measurement and attest to the strength of the implanted sources. The AAPM leaves it to the discretion of the institutional medical physicist whether the manufacturer's or institutional physicist's measured value should be used in performing dosimetry calculations. PMID:18841836

  17. WE-F-BRD-01: HDR Brachytherapy II: Integrating Imaging with HDR

    SciTech Connect

    Craciunescu, O; Todor, D; Leeuw, A de

    2014-06-15

    In recent years, with the advent of high/pulsed dose rate afterloading technology, advanced treatment planning systems, CT/MRI compatible applicators, and advanced imaging platforms, image-guided adaptive brachytherapy treatments (IGABT) have started to play an ever increasing role in modern radiation therapy. The most accurate way to approach IGABT treatment is to provide the infrastructure that combines in a single setting an appropriate imaging device, a treatment planning system, and a treatment unit. The Brachytherapy Suite is not a new concept, yet the modern suites are incorporating state-of-the-art imaging (MRI, CBCT equipped simulators, CT, and /or US) that require correct integration with each other and with the treatment planning and delivery systems. Arguably, an MRI-equipped Brachytherapy Suite is the ideal setup for real-time adaptive brachytherapy treatments. The main impediment to MRI-IGABT adoption is access to MRI scanners. Very few radiation oncology departments currently house MRI scanners, and even fewer in a dedicated Brachytherapy Suite. CBCT equipped simulators are increasingly offered by manufacturers as part of a Brachytherapy Suite installation. If optimized, images acquired can be used for treatment planning, or can be registered with other imaging modalities. This infrastructure is relevant for all forms of brachytherapy, especially those utilizing multi-fractionated courses of treatment such as prostate and cervix. Moreover, for prostate brachytherapy, US imaging systems can be part of the suite to allow for real-time HDR/LDR treatments. Learning Objectives: Understand the adaptive workflow of MR-based IGBT for cervical cancer. Familiarize with commissioning aspects of a CBCT equipped simulator with emphasis on brachytherapy applications Learn about the current status and future developments in US-based prostate brachytherapy.

  18. Ocular Response of Choroidal Melanoma With Monosomy 3 Versus Disomy 3 After Iodine-125 Brachytherapy

    SciTech Connect

    Marathe, Omkar S.; Wu, Jeffrey; Lee, Steve P.; Yu Fei; Burgess, Barry L.; Leu Min; Straatsma, Bradley R.; McCannel, Tara A.

    2011-11-15

    Purpose: To report the ocular response of choroidal melanoma with monosomy 3 vs. disomy 3 after {sup 125}I brachytherapy. Methods and Materials: We evaluated patients with ciliochoroidal melanoma managed with fine needle aspiration biopsy immediately before plaque application for {sup 125}I brachytherapy between January 1, 2005 and December 31, 2008. Patients with (1) cytopathologic diagnosis of melanoma, (2) melanoma chromosome 3 status identified by fluorescence in situ hybridization, and (3) 6 or more months of follow-up after brachytherapy were sorted by monosomy 3 vs. disomy 3 and compared by Kruskal-Wallis test. Results: Among 40 ciliochoroidal melanomas (40 patients), 15 had monosomy 3 and 25 had disomy 3. Monosomy 3 melanomas had a median greatest basal diameter of 12.00 mm and a median tumor thickness of 6.69 mm before brachytherapy; at a median of 1.75 years after brachytherapy, median thickness was 3.10 mm. Median percentage decrease in tumor thickness was 48.3%. Disomy 3 melanomas had a median greatest basal diameter of 10.00 mm and median tumor thickness of 3.19 mm before brachytherapy; at a median of 2.00 years after brachytherapy, median tumor thickness was 2.37 mm. The median percentage decrease in tumor thickness was 22.7%. Monosomy 3 melanomas were statistically greater in size than disomy 3 melanomas (p < 0.001) and showed a greater decrease in tumor thickness after brachytherapy (p = 0.006). Conclusion: In this study, ciliochoroidal melanomas with monosomy 3 were significantly greater in size than disomy 3 melanoma and showed a significantly greater decrease in thickness at a median of 1.75 years after brachytherapy. The greater decrease in monosomy 3 melanoma thickness after brachytherapy is consistent with other malignancies in which more aggressive pathology has been shown to be associated with a greater initial response to radiotherapy.

  19. 21 CFR 880.5965 - Subcutaneous, implanted, intravascular infusion port and catheter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... port and catheter. 880.5965 Section 880.5965 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... port and catheter. (a) Identification. A subcutaneous, implanted, intravascular infusion port and... catheter is either preattached to the port or attached to the port at the time of device placement....

  20. Microfluidics in the Undergraduate Laboratory: Device Fabrication and an Experiment to Mimic Intravascular Gas Embolism

    ERIC Educational Resources Information Center

    Jablonski, Erin L.; Vogel, Brandon M.; Cavanagh, Daniel P.; Beers, Kathryn L.

    2010-01-01

    A method to fabricate microfluidic devices and an experimental protocol to model intravascular gas embolism for undergraduate laboratories are presented. The fabrication process details how to produce masters on glass slides; these masters serve as molds to pattern channels in an elastomeric polymer that can be adhered to a substrate, resulting in…

  1. Treatment of acute intravascular thrombi with diagnostic ultrasound and intravenous microbubbles.

    PubMed

    Xie, Feng; Lof, John; Everbach, Carr; He, Anming; Bennett, Richard M; Matsunaga, Terry; Johanning, Jason; Porter, Thomas R

    2009-04-01

    The purpose of this study was to determine whether high mechanical index (MI) impulses from diagnostic ultrasound (DUS) could dissolve intravascular thrombi using intravenous microbubbles. Using a canine model, DUS was applied during a continuous intravenous infusion of microbubbles. Completely thrombosed grafts were assigned to 2 treatment regimens: low-MI (<0.5-MI) ultrasound alone; or intermittent high-MI impulses (1.9-MI) guided by low-MI ultrasound (contrast pulse sequencing). A 20-MHz cavitation detector was placed confocal to the ultrasound transducer to make intravascular cavitation measurements in 1 dog. Intravascular cavitational activity was detected when an MI of >0.5 was applied. In grafts treated with intermittent high-MI ultrasound, angiographic success was 71% at 30 min and 79% at 45 min, compared with 20% and 30% at these times in the low-MI ultrasound alone group (p < 0.05). We conclude that a commercially available DUS transducer can successfully recanalize acute intravascular thrombi during a continuous microbubble infusion. PMID:19580735

  2. Research of epidermal cellular vegetal cycle of intravascular low level laser irradiation in treatment of psoriasis

    NASA Astrophysics Data System (ADS)

    Zhu, Jing; Bao, Xiaoqing; Zhang, Mei-Jue

    2005-07-01

    Objective: To research epidermal cellular vegetal cycle and the difference of DNA content between pre and post Intravascular Low Level Laser Irradiation treatment of psoriasis. Method: 15 patients suffered from psoriasis were treated by intravascular low level laser irradiation (output power: 4-5mw, 1 hour per day, a course of treatment is 10 days). We checked the different DNA content of epidermal cell between pre and post treatment of psoriasis and 8 natural human. Then the percentage of each phase among the whole cellular cycle was calculated and the statistical analysis was made. Results: The mean value of G1/S phase is obviously down while G2+M phase increased obviously. T test P<0.05.The related statistical analysis showed significant difference between pre and post treatments. Conclusions: The Intravascular Low Level Laser Irradiation (ILLLI) in treatment of psoriasis is effective according to the research of epidermal cellular vegetal cycle and the difference DNA content of Intravascular Low Level Laser Irradiation between pre and post treatment of psoriasis

  3. [Rhabdomyolysis, disseminated intravascular coagulation and multiple organ failure in a patient with cocaine and heroine poisoning].

    PubMed

    Vreugdenhil, G; Ligthart, J; de Leeuw, P W

    1992-06-20

    A 19-year-old female patient with cocaine and heroin intoxication is described in whom several life threatening complications such as hypovolemic shock, cardiopulmonary insufficiency, rhabdomyolysis, diffuse intravascular coagulation and multiple organ failure occurred. The patient survived the intoxication after quick intensive treatment.

  4. Intravascular Optical-Resolution Photoacoustic Tomography with a 1.1 mm Diameter Catheter

    PubMed Central

    Bai, Xiaosong; Gong, Xiaojing; Hau, William; Lin, Riqiang; Zheng, Jiaxiang; Liu, Chengbo; Zeng, Chengzhi; Zou, Xin; Zheng, Hairong; Song, Liang

    2014-01-01

    Photoacoustic imaging is an emerging technology that can provide anatomic, functional, and molecular information about biological tissue. Intravascular spectroscopic and molecular photoacoustic imaging can potentially improve the identification of atherosclerotic plaque composition, the detection of inflammation, and ultimately the risk stratification of atherosclerosis. In this study, a first-of-its-kind intravascular optical-resolution photoacoustic tomography (OR-PAT) system with a 1.1 mm diameter catheter is developed, offering optical-diffraction limited transverse resolution as fine as 19.6 μm, ∼10-fold finer than that of conventional intravascular photoacoustic and ultrasonic imaging. To offer complementary imaging information and depth, the system also acquires co-registered intravascular ultrasound images in parallel. Imaging of an iliac stent and a lipid phantom shows that the high resolution and contrast of OR-PAT can enable improved stent implantation guidance and lipid identification. In the future, these capabilities may ultimately improve the diagnosis and interventional treatment of vulnerable atherosclerotic plaques, which are prone to cause thrombotic complications such as myocardial infarction and stroke. PMID:24651256

  5. Radiological imaging of florid intravascular papillary endothelial hyperplasia in the mandibule: case report and literature review.

    PubMed

    Xu, Sheng-Sheng; Li, Dan

    2014-01-01

    Intravascular papillary endothelial hyperplasia was a rare benign vascular proliferative process as a result of papillary proliferation of the endothelial cells within the vessels. To our knowledge, we reported the second case occurring in the madibule, and the first reported in 1984 in the literature. We discussed manifestations of multislice computed tomography and panoramic radiography about the lesion and relevant literature was reviewed.

  6. Dynamic modulated brachytherapy (DMBT) and intensity modulated brachytherapy (IMBT) for the treatment of rectal and breast carcinomas

    NASA Astrophysics Data System (ADS)

    Webster, Matthew Julian

    The ultimate goal of any treatment of cancer is to maximize the likelihood of killing the tumor while minimizing the chance of damaging healthy tissues. One of the most effective ways to accomplish this is through radiation therapy, which must be able to target the tumor volume with a high accuracy while minimizing the dose delivered to healthy tissues. A successful method of accomplishing this is brachytherapy which works by placing the radiation source in very close proximity to the tumor. However, most current applications of brachytherapy rely mostly on the geometric manipulation of isotropic sources, which limits the ability to specifically target the tumor. The purpose of this work is to introduce several types of shielded brachytherapy applicators which are capable of targeting tumors with much greater accuracy than existing technologies. These applicators rely on the modulation of the dose profile through a high-density tungsten alloy shields to create anisotropic dose distributions. Two classes of applicators have been developed in this work. The first relies on the active motion of the shield, to aim a highly directional radiation profile. This allows for very precise control of the dose distribution for treatment, achieving unparalleled dose coverage to the tumor while sparing healthy tissues. This technique has been given the moniker of Dynamic Modulated Brachytherapy (DMBT). The second class of applicators, designed to reduce treatment complexity uses static applicators. These applicators retain the use of the tungsten shield, but the shield is motionless during treatment. By intelligently designing the shield, significant improvements over current methods have been demonstrated. Although these static applicators fail to match the dosimetric quality of DMBT applicators the simplified setup and treatment procedure gives them significant appeal. The focus of this work has been to optimize these shield designs, specifically for the treatment of rectal and

  7. Evaluation of Intravascular Hemolysis With Erythrocyte Creatine in Patients With Aortic Stenosis.

    PubMed

    Sugiura, Tetsuro; Okumiya, Toshika; Kubo, Toru; Takeuchi, Hiroaki; Matsumura, Yoshihisa

    2016-07-27

    Chronic intravascular hemolysis has been identified in patients with cardiac valve prostheses, but only a few case reports have evaluated intravascular hemolysis in patients with native valvular heart disease. To detect intravascular hemolysis in patients with aortic stenosis, erythrocyte creatine was evaluated with hemodynamic indices obtained by echocardiography.Erythrocyte creatine, a marker of erythrocyte age, was assayed in 30 patients with aortic stenosis and 10 aged matched healthy volunteers. Peak flow velocity of the aortic valve was determined by continuous-wave Doppler echocardiography. Twenty of 30 patients with aortic stenosis had high erythrocyte creatine levels (> 1.8 µmol/g Hb) and erythrocyte creatine was significantly higher as compared with control subjects (1.98 ± 0.49 versus 1.52 ± 0.19 µmol/g Hb, P = 0.007). Peak transvalvular pressure gradient ranged from 46 to 142 mmHg and peak flow velocity ranged from 3.40 to 5.95 m/second. Patients with aortic stenosis had a significantly lower erythrocyte count (387 ± 40 versus 436 ± 42 × 10(4) µL, P = 0.002) and hemoglobin (119 ± 11 versus 135 ± 11 g/L, P < 0.001) as compared with control subjects. Erythrocyte creatine had a fair correlation with peak flow velocity (r = 0.55, P = 0.002).In conclusion, intravascular hemolysis due to destruction of erythrocytes was detected in patients with moderate to severe aortic stenosis and the severity of intravascular hemolysis was related to valvular flow velocity of the aortic valve.

  8. Asphyxia by Drowning Induces Massive Bleeding Due To Hyperfibrinolytic Disseminated Intravascular Coagulation

    PubMed Central

    Schwameis, Michael; Schober, Andreas; Schörgenhofer, Christian; Sperr, Wolfgang Reinhard; Schöchl, Herbert; Janata-Schwatczek, Karin; Kürkciyan, Erol Istepan; Sterz, Fritz

    2015-01-01

    Objective: To date, no study has systematically investigated the impact of drowning-induced asphyxia on hemostasis. Our objective was to test the hypothesis that asphyxia induces bleeding by hyperfibrinolytic disseminated intravascular coagulation. Design: Observational study. Setting: A 2,100-bed tertiary care facility in Vienna, Austria, Europe. Patients: All cases of drowning-induced asphyxia (n = 49) were compared with other patients with cardiopulmonary resuscitation (n = 116) and to patients with acute promyelocytic leukemia (n = 83). Six drowning victims were investigated prospectively. To study the mechanism, a forearm-ischemia model was used in 20 volunteers to investigate whether hypoxia releases tissue plasminogen activator. Interventions: None. Measurements and Main Results: Eighty percent of patients with drowning-induced asphyxia developed overt disseminated intravascular coagulation within 24 hours. When compared with nondrowning cardiac arrest patients, drowning patients had a 13 times higher prevalence of overt disseminated intravascular coagulation at admission (55% vs 4%; p < 0.001). Despite comparable disseminated intravascular coagulation scores, acute promyelocytic leukemia patients had higher fibrinogen but lower d-dimer levels and platelet counts than drowning patients (p < 0.001). Drowning victims had a three-fold longer activated partial thromboplastin time (124 s; p < 0.001) than both nondrowning cardiac arrest and acute promyelocytic leukemia patients. Hyperfibrinolysis was reflected by up to 1,000-fold increased d-dimer levels, greater than 5-fold elevated plasmin antiplasmin levels, and a complete absence of thrombelastometric clotting patterns, which was reversed by antifibrinolytics and heparinase. Thirty minutes of forearm-ischemia increased tissue plasminogen activator 31-fold (p < 0.001). Conclusions: The vast majority of drowning patients develops overt hyperfibrinolytic disseminated intravascular coagulation, partly caused by

  9. Intravascular pressure augments cerebral arterial constriction by inducing voltage-insensitive Ca2+ waves.

    PubMed

    Mufti, Rania E; Brett, Suzanne E; Tran, Cam Ha T; Abd El-Rahman, Rasha; Anfinogenova, Yana; El-Yazbi, Ahmed; Cole, William C; Jones, Peter P; Chen, S R Wayne; Welsh, Donald G

    2010-10-15

    This study examined whether elevated intravascular pressure stimulates asynchronous Ca(2+) waves in cerebral arterial smooth muscle cells and if their generation contributes to myogenic tone development. The endothelium was removed from rat cerebral arteries, which were then mounted in an arteriograph, pressurized (20-100 mmHg) and examined under a variety of experimental conditions. Diameter and membrane potential (V(M)) were monitored using conventional techniques; Ca(2+) wave generation and myosin light chain (MLC(20))/MYPT1 (myosin phosphatase targeting subunit) phosphorylation were assessed by confocal microscopy and Western blot analysis, respectively. Elevating intravascular pressure increased the proportion of smooth muscle cells firing asynchronous Ca(2+) waves as well as event frequency. Ca(2+) wave augmentation occurred primarily at lower intravascular pressures (<60 mmHg) and ryanodine, a plant alkaloid that depletes the sarcoplasmic reticulum (SR) of Ca(2+), eliminated these events. Ca(2+) wave generation was voltage insensitive as Ca(2+) channel blockade and perturbations in extracellular [K(+)] had little effect on measured parameters. Ryanodine-induced inhibition of Ca(2+) waves attenuated myogenic tone and MLC(20) phosphorylation without altering arterial V(M). Thapsigargin, an SR Ca(2+)-ATPase inhibitor also attenuated Ca(2+) waves, pressure-induced constriction and MLC(20) phosphorylation. The SR-driven component of the myogenic response was proportionally greater at lower intravascular pressures and subsequent MYPT1 phosphorylation measures revealed that SR Ca(2+) waves facilitated pressure-induced MLC(20) phosphorylation through mechanisms that include myosin light chain phosphatase inhibition. Cumulatively, our findings show that mechanical stimuli augment Ca(2+) wave generation in arterial smooth muscle and that these transient events facilitate tone development particularly at lower intravascular pressures by providing a proportion of the Ca

  10. Conformal Brachytherapy Planning for Cervical Cancer Using Transabdominal Ultrasound

    SciTech Connect

    Van Dyk, Sylvia Narayan, Kailash; Fisher, Richard; Bernshaw, David

    2009-09-01

    Purpose: To determine if transabdominal ultrasound (US) can be used for conformal brachytherapy in cervical cancer patients. Materials and Methods: Seventy-one patients with locoregionally advanced cervix cancer treated with chemoradiation and brachytherapy were included in this study. The protocol consisted of US-assisted tandem insertion and conformal US-based planning. Orthogonal films for applicator reconstruction were also taken. A standard plan was modified to suit the US-based volume and treatment was delivered. The patient then underwent a magnetic resonance imaging (MRI) scan with the applicators in situ. Retrospectively, individual standard (STD), US, and MRI plans were extrapolated for five fractions and superimposed onto the two-dimensional sagittal MRI images for comparison. Doses to Point A, target volume, International Commission on Radiation Units and Measurements (ICRU) 38 bladder and rectal points, and individualized bowel points were calculated on original implant geometry on Plato for each planning method. Results: STD (high-dose-rate) plans reported higher doses to Point A, target volume, ICRU 38 bladder and rectal points, and individualized bowel point compared with US and MRI plans. There was a statistically significant difference between standard plans and image-based plans-STD vs. US, STD vs. MRI, and STD vs. Final-having consistent (p {<=} 0.001) respectively for target volume, Point A, ICRU 38 bladder, and bowel point. US plan assessed on two-dimensional MRI image was comparable for target volume (p = 0.11), rectal point (p = 0.8), and vaginal mucosa (p = 0.19). Local control was 90%. Late bowel morbidity (G3, G4) was <2%. Conclusions: Transabdominal ultrasound offers an accurate, quick, accessible, and cost-effective method of conformal brachytherapy planning.

  11. Prostate Brachytherapy in Men {>=}75 Years of Age

    SciTech Connect

    Merrick, Gregory S. Wallner, Kent E.; Galbreath, Robert W.; Butler, Wayne M.; Brammer, Sarah G.; Allen, Zachariah A.; Adamovich, Edward

    2008-10-01

    Purpose: To evaluate cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) in prostate cancer patients aged {>=}75 years undergoing brachytherapy with or without supplemental therapies. Methods and Materials: Between April 1995 and August 2004, 145 consecutive patients aged {>=}75 years underwent permanent prostate brachytherapy. Median follow-up was 5.8 years. Biochemical progression-free survival was defined by a prostate-specific antigen level {<=}0.40 ng/mL after nadir. Patients with metastatic prostate cancer or hormone-refractory disease without obvious metastases who died of any cause were classified as dead of prostate cancer. All other deaths were attributed to the immediate cause of death. Multiple clinical, treatment, and dosimetric parameters were evaluated for impact on survival. Results: Nine-year CSS, bPFS, and OS rates for the entire cohort were 99.3%, 97.1%, and 64.5%, respectively. None of the evaluated parameters predicted for CSS, whereas bPFS was most closely predicted by percentage positive biopsies. Overall survival and non-cancer deaths were best predicted by tobacco status. Thirty-seven patients have died, with 83.8% of the deaths due to cardiovascular disease (22 patients) or second malignancies (9 patients). To date, only 1 patient (0.7%) has died of metastatic prostate cancer. Conclusions: After brachytherapy, high rates of CSS and bPFS are noted in elderly prostate cancer patients. Overall, approximately 65% of patients are alive at 9 years, with survival most closely related to tobacco status. We believe our results support an aggressive locoregional approach in appropriately selected elderly patients.

  12. Study of dose calculation on breast brachytherapy using prism TPS

    SciTech Connect

    Fendriani, Yoza; Haryanto, Freddy

    2015-09-30

    PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm{sup 3}. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm{sup 3}. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy.

  13. Use of radiochromic dosimetry film for HDR brachytherapy quality assurance.

    PubMed

    Steidley, K D

    1998-01-01

    An important quality assurance (QA) procedure in high dose rate (HDR) remote afterloading brachytherapy is the verification of the system's control of the source by a direct test with dosimetry medium prior to the patient's first treatment. In this test radiochromic film is placed in direct contact with the applicator and the patient's proposed treatment is then run with their EPROM card. Examination of the film allows a quick appraisal of step size, number of steps, and offset. Advantages of this film include self-development so the image may be viewed immediately, insensitivity to normal room light, and archivability. The cost is about U.S. $2 per clinical case.

  14. Radiological response of ceramic and polymeric devices for breast brachytherapy.

    PubMed

    Nogueira, Luciana Batista; de Campos, Tarcisio Passos Ribeiro

    2012-04-01

    In the present study, the radiological visibility of ceramic and polymeric devices implanted in breast phantom was investigated for future applications in brachytherapy. The main goal was to determine the radiological viability of ceramic and polymeric devices in vitro by performing simple radiological diagnostic methods such as conventional X-ray analysis and mammography due to its easy access to the population. The radiological response of ceramic and polymeric devices implanted in breast phantom was determined using conventional X-ray, mammography and CT analysis.

  15. [Endobronchial brachytherapy: state of the art in 2013].

    PubMed

    Derhem, N; Sabila, H; Mornex, F

    2013-04-01

    Endobronchial brachytherapy is an invasive technique, which allows localizing radioactive sources at the tumour contact. Therefore, high doses are administered to tumour while healthy tissues can be spared. Initially dedicated to a palliative setting, improvements helped reaching 60 to 88% symptoms alleviation and 30 to 100% of endoscopic macroscopic response. New diagnostic techniques and early diagnosis extended the indications to a curative intent: endoluminal primitive tumour, post radiation endobronchial recurrence, inoperable patients. CT-based dosimetry is a keypoint to optimize treatment quality and to minimize potential side effects, making this treatment a safe and efficient technique for specific indications. PMID:23465785

  16. [The successful prolongation of a twin preterm pregnancy complicated by a dead fetus and disseminated intravascular coagulation].

    PubMed

    Hasbún, J; Muñoz, H; von Mühlenbrock, R; Pommer, R; Fardella, P; Yuri, C

    1992-01-01

    A clinical case of twin pregnancy with one in utero death fetus, at 24 weeks of gestation is presented, accompanied by disseminated intravascular coagulation. The successful treatment with heparin its described.

  17. Optimizing methods for the study of intravascular lipid metabolism in zebrafish.

    PubMed

    Chen, Kan; Wang, Chang-Qian; Fan, Yu-Qi; Xie, Yu-Shui; Yin, Zhao-Fang; Xu, Zuo-Jun; Zhang, Hui-Li; Cao, Jia-Tian; Han, Zhi-Hua; Wang, Yue; Song, Dong-Qiang

    2015-03-01

    The zebrafish (Danio rerio) is a useful vertebrate model for use in cardiovascular drug discovery. The present study aimed to construct optimized methods for the study of intravascular lipid metabolism of zebrafish. The lipophilic dye, Oil Red O, was used to stain fasting zebrafish one to eight days post-fertilization (dpf) and to stain 7-dpf zebrafish incubated in a breeding system containing 0.1% egg yolk as a high-fat diet (HFD) for 48 h. Three-dpf zebrafish were kept in CholEsteryl boron-dipyrromethene (BODIPY) 542/563 C11 water for 24 h which indicated the efficiency of CholEsteryl BODIPY 542/563 C11 intravascular cholesterol staining. Subsequently, 7-dpf zebrafish were incubated in water containing the fluorescent probe CholEsteryl BODIPY 542/563 C11 and fed a high-cholesterol diet (HCD) for 10 d. Two groups of 7-dpf zebrafish were incubated in regular breeding water and fed with a regular or HCD containing CholEsteryl BODIPY 542/563 C11 for 10 d. Finally, blood lipids of adult zebrafish fed with regular or HFD for seven weeks were measured. Oil Red O was not detected in the blood vessels of 7-8-dpf zebrafish. Increased intravascular lipid levels were detected in 7-dpf zebrafish incubated in 0.1% egg yolk, indicated by Oil Red O staining. Intravascular cholesterol was efficiently stained in 3-dpf zebrafish incubated in breeding water containing CholEsteryl BODIPY 542/563 C11; however, this method was inappropriate for the calculation of intravascular fluorescence intensity in zebrafish >7‑dpf. In spite of this, intra-aortic fluorescence intensity of zebrafish fed a HCD containing CholEsteryl BODIPY 542/563 C11 was significantly higher (P<0.05) than that of those fed a regular diet containing CholEsteryl BODIPY 542/563 C11. The serum total cholesterol and triglyceride levels of adult zebrafish fed a HFD were markedly increased compared to those of the control group (P<0.05). In conclusion, the use of Oil Red O staining and CholEsteryl BODIPY 542/563 C11 may

  18. Dosimetric Study of a Low-Dose-Rate Brachytherapy Source

    NASA Astrophysics Data System (ADS)

    Rodríguez-Villafuerte, M.; Arzamendi, S.; Díaz-Perches, R.

    Carcinoma of the cervix is the most common malignancy - in terms of both incidence and mortality - in Mexican women. Low dose rate (LDR) intracavitary brachytherapy is normally prescribed for the treatment of this disease to the vast majority of patients attending public hospitals in our country. However, most treatment planning systems being used in these hospitals still rely on Sievert integral dose calculations. Moreover, experimental verification of dose distributions are hardly ever done. In this work we present a dosimetric characterisation of the Amersham CDCS-J 137Cs source, an LDR brachytherapy source commonly used in Mexican hospitals. To this end a Monte Carlo simulation was developed, that includes a realistic description of the internal structure of the source embedded in a scattering medium. The Monte Carlo results were compared to experimental measurements of dose distributions. A lucite phantom with the same geometric characteristics as the one used in the simulation was built. Dose measurements were performed using thermoluminescent dosimeters together with commercial RadioChromic dye film. A comparison between our Monte Carlo simulation, the experimental data, and results reported in the literature is presented.

  19. 2D/3D registration algorithm for lung brachytherapy

    SciTech Connect

    Zvonarev, P. S.; Farrell, T. J.; Hunter, R.; Wierzbicki, M.; Hayward, J. E.; Sur, R. K.

    2013-02-15

    Purpose: A 2D/3D registration algorithm is proposed for registering orthogonal x-ray images with a diagnostic CT volume for high dose rate (HDR) lung brachytherapy. Methods: The algorithm utilizes a rigid registration model based on a pixel/voxel intensity matching approach. To achieve accurate registration, a robust similarity measure combining normalized mutual information, image gradient, and intensity difference was developed. The algorithm was validated using a simple body and anthropomorphic phantoms. Transfer catheters were placed inside the phantoms to simulate the unique image features observed during treatment. The algorithm sensitivity to various degrees of initial misregistration and to the presence of foreign objects, such as ECG leads, was evaluated. Results: The mean registration error was 2.2 and 1.9 mm for the simple body and anthropomorphic phantoms, respectively. The error was comparable to the interoperator catheter digitization error of 1.6 mm. Preliminary analysis of data acquired from four patients indicated a mean registration error of 4.2 mm. Conclusions: Results obtained using the proposed algorithm are clinically acceptable especially considering the complications normally encountered when imaging during lung HDR brachytherapy.

  20. Observations on rotating needle insertions using a brachytherapy robot

    NASA Astrophysics Data System (ADS)

    Meltsner, M. A.; Ferrier, N. J.; Thomadsen, B. R.

    2007-09-01

    A robot designed for prostate brachytherapy implantations has the potential to greatly improve treatment success. Much of the research in robotic surgery focuses on measuring accuracy. However, there exist many factors that must be optimized before an analysis of needle placement accuracy can be determined. Some of these parameters include choice of the needle type, insertion velocity, usefulness of the rotating needle and rotation speed. These parameters may affect the force at which the needle interacts with the tissue. A reduction in force has been shown to decrease the compression of the prostate and potentially increase the accuracy of seed position. Rotating the needle as it is inserted may reduce frictional forces while increasing accuracy. However, needle rotations are considered to increase tissue damage due to the drilling nature of the insertion. We explore many of the factors involved in optimizing a brachytherapy robot, and the potential effects each parameter may have on the procedure. We also investigate the interaction of rotating needles in gel and suggest the rotate-cannula-only method of conical needle insertion to minimize any tissue damage while still maintaining the benefits of reduced force and increased accuracy.

  1. In vivo visualization of prostate brachytherapy seeds with photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Lediju Bell, Muyinatu A.; Kuo, Nathanael P.; Song, Danny Y.; Kang, Jin U.; Boctor, Emad M.

    2014-12-01

    We conducted a canine study to investigate the in vivo feasibility of photoacoustic imaging for intraoperative updates to brachytherapy treatment plans. A fiber coupled to a 1064-nm Nd:YAG laser was inserted into high-dose-rate brachytherapy needles, which diffused light spherically. These needles were inserted through the perineum into the prostate for interstitial light delivery and the resulting acoustic waves were detected with a transrectal ultrasound probe. Postoperative computed tomography images and ex vivo photoacoustic images confirmed seed locations. Limitations with insufficient light delivery were mitigated with short-lag spatial coherence (SLSC) beamforming, providing a 10-20 dB contrast improvement over delay-and-sum (DAS) beamforming for pulse energies ranging from 6.8 to 10.5 mJ with a fiber-seed distance as large as 9.5 mm. For the same distance and the same range of energy densities, signal-to-noise ratios (SNRs) were similar while the contrast-to-noise ratio (CNR) was higher in SLSC compared to DAS images. Challenges included visualization of signals associated with the interstitial fiber tip and acoustic reverberations between seeds separated by ≤2 mm. Results provide insights into the potential for clinical translation to humans.

  2. A Brachytherapy Plan Evaluation Tool for Interstitial Applications

    PubMed Central

    Nambiraj, N. Arunai; Dayalan, Sridhar; Ganesh, Kalaivany; Anchineyan, Pichandi; Bilimagga, Ramesh S.

    2014-01-01

    Radiobiological metrics such as tumor control probability (TCP) and normal tissue complication probability (NTCP) help in assessing the quality of brachytherapy plans. Application of such metrics in clinics as well as research is still inadequate. This study presents the implementation of two indigenously designed plan evaluation modules: Brachy_TCP and Brachy_NTCP. Evaluation tools were constructed to compute TCP and NTCP from dose volume histograms (DVHs) of any interstitial brachytherapy treatment plan. The computation module was employed to estimate probabilities of tumor control and normal tissue complications in ten cervical cancer patients based on biologically effective equivalent uniform dose (BEEUD). The tumor control and normal tissue morbidity were assessed with clinical followup and were scored. The acute toxicity was graded using common terminology criteria for adverse events (CTCAE) version 4.0. Outcome score was found to be correlated with the TCP/NTCP estimates. Thus, the predictive ability of the estimates was quantified with the clinical outcomes. Biologically effective equivalent uniform dose-based formalism was found to be effective in predicting the complexities and disease control. PMID:24665263

  3. Thermoluminescence dosimetry measurements of brachytherapy sources in liquid water

    SciTech Connect

    Tailor, Ramesh; Tolani, Naresh; Ibbott, Geoffrey S.

    2008-09-15

    Radiation therapy dose measurements are customarily performed in liquid water. The characterization of brachytherapy sources is, however, generally based on measurements made with thermoluminescence dosimeters (TLDs), for which contact with water may lead to erroneous readings. Consequently, most dosimetry parameters reported in the literature have been based on measurements in water-equivalent plastics, such as Solid Water. These previous reports employed a correction factor to transfer the dose measurements from a plastic phantom to liquid water. The correction factor most often was based on Monte Carlo calculations. The process of measuring in a water-equivalent plastic phantom whose exact composition may be different from published specifications, then correcting the results to a water medium leads to increased uncertainty in the results. A system has been designed to enable measurements with TLDs in liquid water. This system, which includes jigs to support water-tight capsules of lithium fluoride in configurations suitable for measuring several dosimetric parameters, was used to determine the correction factor from water-equivalent plastic to water. Measurements of several {sup 125}I and {sup 131}Cs prostate brachytherapy sources in liquid water and in a Solid Water phantom demonstrated a correction factor of 1.039{+-}0.005 at 1 cm distance. These measurements are in good agreement with a published value of this correction factor for an {sup 125}I source.

  4. Remote afterloading for intracavitary and interstitial brachytherapy with californium-252

    NASA Astrophysics Data System (ADS)

    Tačev, Tačo; Grigorov, Grigor; Papírek, Tomáš; Kolařík, Vladimír.

    2004-01-01

    The authors present their design concept of remote afterloading for 252Cf brachytherapy with respect to characteristic peculiarities of 252Cf and the current worldwide development of remote afterloading devices. The afterloading device has been designed as a stationary radiator comprising three mutually interconnected units: (1) a control and drive unit, consisting of a control computer and a motor-driven Bowden system carrying the 252Cf source; (2) a source housed in a watertight, concrete vessel, which is stored in a strong room situated well beneath the patient's bed and (3) an afterloading application module installed in the irradiation room. As 252Cf is a nuclide with low specific activity, it was necessary to produce two independent devices for high dose rate intracavitary treatment and for low dose rate intestinal treatment. The sources may be moved arbitrarily during the treatment with a position accuracy of 0.5-1.0 mm within a distance of 520 cm from the source storage position in the strong room to the application position. The technical concept of the present automatic afterloading device for neutron brachytherapy represents one possible option of a range of conceivable design variants, which, while minimizing the technical and economic requirements, provides operating personnel with optimum protection and work safety, thus extending the applicability of high-LET radiation-based treatment methods in clinical practice.

  5. [Intravascular biocompatibility of decellularized xenogenic vascular scaffolds/PHBHHx hybrid material for cardiovascular tissue engineering].

    PubMed

    Wu, Song; Liu, Yinglong; Cui, Bin; Tang, Yue; Wang, Qiang; Qu, Xianghua; Chen, Guoqiang

    2008-04-01

    Poly (3-hydroxybutyrate-co-3-hydroxyhexanoate, PHBHHx) has superior mechanical and biocompatibility that may enable it to meet cardiovascular tissue engineering applications. We developed hybrid materials based on decellularized xenogenic vascular scaffolds that were coated with PHBHHx to investigate the intravascular biocompatibility. The hybrid patches were implanted in the rabbit abdominal aorta (hybrid patch, n = 12). Only decellularized xenogenic vascular scaffolds were implanted without coating as control (uncoated patch, n = 12). The patches were explanted and examined histologically, and biochemically at 1, 4 and 12 weeks after the surgery. The hybrid patches maintained original shapes, covered by confluent layer of cells and had less calcification than uncoated control. The results indicated that PHBHHx coating reduced calcification, promoted the repopulation of hybrid patch with recipients cells. In conclusion, PHBHHx showed remarkable intravascular biocompatibility and would benefit endothelization which would be a useful candidate for lumen of cardiovascular tissue engineering. PMID:18616171

  6. An Arthrobacter spp. bacteremia leading to fetal death and maternal disseminated intravascular coagulation.

    PubMed

    Shigeta, Naoya; Ozaki, Kimiaki; Hori, Kensuke; Ito, Kimihiko; Nakayama, Masahiro; Nakahira, Kumiko; Yanagihara, Itaru

    2013-02-01

    A 34-year-old parous woman developed high fever and threatened preterm labor after a 1-day trip, for which she was receiving prenatal care at a hospital. Three days after onset, at 24 4/7 weeks of gestation, she was transferred to our hospital in an emergency. Soon after the woman's arrival at our hospital, the infant was spontaneously stillborn via a transvaginal delivery. Laboratory tests revealed severe maternal disseminated intravascular coagulation with renal and liver insufficiency. Histopathologic examination of the placenta revealed vast fibrin deposition and remarkable neutrophilic infiltration in the intervillous space, suggesting a rare bacterial infection caused by Arthrobacter spp. The bacteria were predominantly detected in the placenta and maternal blood serum by common bacterial 16S rRNA sequencing after polymerase chain reaction amplification. We report the first case, to our knowledge, of bacteremia with Arthrobacter spp., which may lead to maternal disseminated intravascular coagulation and intrauterine fetal death.

  7. Intravascular photoacoustic imaging of exogenously labeled atherosclerotic plaque through luminal blood

    PubMed Central

    Yeager, Doug; Karpiouk, Andrei; Wang, Bo; Amirian, James; Sokolov, Konstantin; Smalling, Richard

    2012-01-01

    Abstract. Combined intravascular ultrasound and intravascular photoacoustic (IVUS/IVPA) imaging has been previously established as a viable means for assessing atherosclerotic plaque morphological and compositional characteristics using both endogenous and exogenous contrast. In this study, IVUS/IVPA imaging of atherosclerotic rabbit aortas following systemic injection of gold nanorods (AUNRs) with peak absorbance within the tissue optical window is performed. Ex vivo imaging results reveal a high photoacoustic signal from localized AUNRs in regions with atherosclerotic plaques. Corresponding histological staining further confirms the preferential extravasation of AUNRs in atherosclerotic regions with compromised luminal endothelium and acute inflammation. The ability to detect AUNRs using combined IVUS and photoacoustic imaging in the presence of luminal saline and luminal blood is evaluated using both spectroscopic and single wavelength IVPA imaging techniques. Results demonstrate that AUNR detection within the arterial wall can be achieved using both methods, even in the case of imaging through luminal blood. PMID:23224013

  8. Enhanced glucose tolerance by intravascularly administered piceatannol in freely moving healthy rats.

    PubMed

    Oritani, Yukihiro; Okitsu, Teru; Nishimura, Eisaku; Sai, Masahiko; Ito, Tatsuhiko; Takeuchi, Shoji

    2016-02-12

    Piceatannol is a phytochemical in the seeds of passion fruit that has a hypoglycemic effect when orally administered. To elucidate the contribution of intact and metabolites of piceatannol after gastro-intestinal absorption to hypoglycemic effect, we examined the influence of piceatannol and isorhapontigenin on blood glucose concentrations during fasting and glucose tolerance tests by administering them intravascularly to freely moving healthy rats. We found that intravascularly administered piceatannol reduced the blood glucose concentrations during both fasting and glucose tolerance tests, but isorhapontigenin did not during either of them. Furthermore, we found that piceatannol increased the insulinogenic index during glucose tolerance tests and that piceatannol had no influence on insulin sensitivity by performing hyperinsulinemic euglycemic clamping tests. These results suggest that piceatannol orally intaken may enhance glucose tolerance by the effect of intact piceatannol through enhanced early-phase secretion of insulin. Therefore, oral intake of piceatannol might contribute to proper control of postprandial glycemic excursions in healthy subjects.

  9. [Intravascular lymphoma treated with anti CD20 monoclonal antibodies. Report of one case].

    PubMed

    Alfaro, Jorge; Espinoza, Arturo; Manŕiquez, María; Moyano, Leonor; González, Néstor; Larrondo, Milton; Figueroa, Gastón

    2004-11-01

    We report a 78 year old male with prostatism, that was subjected to a prostate biopsy. The pathological study showed a microvascular lymphocytic infiltration. Four months later, the patients presented with reduced alertness, cough, dyspnea, fever and elevation of lactic dehydrogenase and erythrocyte sedimentation rate. Chest and abdominal CAT scans, bone marrow aspirate, protein electrophoresis and prostate specific antigen were normal. A re-evaluation of prostate biopsy showed an intravascular lymphoid infiltration, positive for CD45 and CD20, compatible with the diagnosis of intravascular lymphoma. Chemotherapy was started, but it was not tolerated by the patient and the response was partial. Therefore, treatment with monoclonal antibodies anti CD20 (Rituximab) was started. The tumor had a complete and prolonged (24 months) remission after the treatment

  10. Systematic Review of Focal Prostate Brachytherapy and the Future Implementation of Image-Guided Prostate HDR Brachytherapy Using MR-Ultrasound Fusion.

    PubMed

    Peach, M Sean; Trifiletti, Daniel M; Libby, Bruce

    2016-01-01

    Prostate cancer is the most common malignancy found in North American and European men and the second most common cause of cancer related death. Since the practice of PSA screening has become common the disease is most often found early and can have a long indolent course. Current definitive therapy treats the whole gland but has considerable long-term side effects. Focal therapies may be able to target the cancer while decreasing dose to organs at risk. Our objective was to determine if focal prostate brachytherapy could meet target objectives while permitting a decrease in dose to organs at risk in a way that would allow future salvage treatments. Further, we wanted to determine if focal treatment results in less toxicity. Utilizing the Medline repository, dosimetric papers comparing whole gland to partial gland brachytherapy and clinical papers that reported toxicity of focal brachytherapy were selected. A total of 9 dosimetric and 6 clinical papers met these inclusion criteria. Together, these manuscripts suggest that focal brachytherapy may be employed to decrease dose to organs at risk with decreased toxicity. Of current technology, image-guided HDR brachytherapy using MRI registered to transrectal ultrasound offers the flexibility and efficiency to achieve such focal treatments. PMID:27293899

  11. Intravascular ATP and the regulation of blood flow and oxygen delivery in humans.

    PubMed

    Crecelius, Anne R; Kirby, Brett S; Dinenno, Frank A

    2015-01-01

    Regulation of vascular tone is a complex response that integrates multiple signals that allow for blood flow and oxygen supply to match oxygen demand appropriately. Here, we discuss the potential role of intravascular adenosine triphosphate (ATP) as a primary factor in these responses and put forth the hypothesis that deficient ATP release contributes to impairments in vascular control exhibited in aged and diseased populations. PMID:25390296

  12. Study of restenosis in drug eluting stents: new insights from greyscale intravascular ultrasound and virtual histology.

    PubMed

    Garcia-Garcia, Hector M; Shen, Zhujun; Piazza, Nicolo

    2009-05-01

    In current cardiology practice, many patients undergo secondary revascularisation due to reduced long-term vein graft patency or in-stent restenosis. In this report, we describe causes of drug-eluting stent restenosis identifiable by intravascular ultrasound imaging (IVUS) and variables related to restenosis used for reporting greyscale IVUS. In addition, IVUS findings in bypass grafts and the long-term results after stent implantation are provided. Finally, the usefulness of IVUS virtual histology for the study of restenosis is described.

  13. Laparoscopic Manipulation of a Probe-based Confocal Laser Endomicroscope Using a Steerable Intravascular Catheter

    PubMed Central

    Desjardins, Adrien E.; Gurusamy, Kurinchi; Hawkes, David J.; Davidson, Brian R.

    2015-01-01

    Probe-based confocal laser endomicroscopy is an emerging imaging modality that enables visualization of histologic details during endoscopy and surgery. A method of guiding the probe with millimeter accuracy is required to enable imaging in all regions of the abdomen accessed during laparoscopy. On the basis of a porcine model of laparoscopic liver resection, we report our experience of using a steerable intravascular catheter to guide a probe-based confocal laser endomicroscope. PMID:25807277

  14. Surgical management of Wilms tumor with intravascular extension: a single-institution experience.

    PubMed

    Aspiazu, Diego; Fernandez-Pineda, Israel; Cabello, Rosa; Ramirez, Gema; Alvarez-Madrid, Antonio; De Agustin, Juan Carlos

    2012-02-01

    The purpose of this study was to retrospectively analyze the clinical presentation, treatment, and outcomes of children with Wilms tumor (WT) and intravascular extension who were treated at a single institution. A retrospective review was conducted of medical records of all children with Wilms tumor and intravascular extension treated at Virgen del Rocio Children's Hospital between 1992 and 2010. Seven patients (median age 3.4 years, range 2-8.1 years) were identified. At diagnosis, 6 of the 7 patients (85.7%) presented with tumor thrombus that reached the right atrium (RA) and 1 patient with infrahepatic inferior vena cava (IVC) thrombus. All patients received neoadjuvant chemotherapy (SIOP 2001 protocol) with vincristine, doxorubicin, and actinomycin D. Regression of the intravascular extension of the tumor was documented in all patients. Postchemotherapy level of extension was suprahepatic IVC in 1 patient, infrahepatic IVC in 2 patients, renal vein (RV) in 1 patient, and RA in 3 patients. Nephrectomy and thrombectomy were performed in all cases, requiring cardiopulmonary bypass for the 4 patients who presented with suprahepatic IVC and RA thrombus. The other 3 patients with infrahepatic IVC and RV involvement underwent cavotomy and thrombus extraction. Computed tomography, ultrasonography, and echocardiography were used for diagnosis and follow-up. All patients remain disease-free with a median follow-up of 6.3 years (range, 2-19 years). Neoadjuvant chemotherapy for WT with intravascular extension may facilitate the resection by decreasing the extent of the tumor thrombus. Cardiopulmonary bypass is indicated for suprahepatic IVC and RA involvement. Accurate diagnostic imaging is necessary.

  15. Recurrent thrombotic occlusions of arteries and veins caused by intravascular metastatic adenocarcinoma.

    PubMed Central

    Levi, M; Bronkhorst, C; Noorduyn, L A; Vreeken, J

    1994-01-01

    The occurrence of unexplained, rapidly recurring occlusions of arteries and veins in a previously healthy young woman is described. Post mortem examination showed no macroscopic abnormalities but revealed microscopic metastatic adenocarcinoma with remarkable intravascular localisation of the malignant cells. Whereas highly sensitive markers for the existence of systemic activation of blood coagulation remained within the normal range, it is suggested that specific characteristics of the tumour cells may have been responsible for this particular clinical presentation. PMID:7962660

  16. Effect of intravascular irradiation of He-Ne laser on cerebral infarction: Hemorrheology and apoptosis

    NASA Astrophysics Data System (ADS)

    Zhu, Jian; Liang, Min-yi; Cao, Hao-cai; Li, Xiao-Yuan; Li, Shao-ming; Li, Shun-hao; Li, Wen-qi; Zhang, Jin-hong; Liu, Lei; Lai, Jian-hong

    2005-07-01

    Objective: To explore the efficacy of He-Ne laser intravascular irradiation on infarction and hemorrheology. To observe the effects of intravascular low level He-Ne laser irradiation (ILLLI) of blood on cell proliferation, apoptosis and chromosome in lymphocyte from cerebral infarction Methods: Seventy cases with cerebral infarction were randomly divided into groups control group (35 cases) treated only with common drugs and therapeutic group (35 cases) treated besides common drugs also by He-Ne laser intravascular irradiation. Their hemorrheology index and treatment results were observed and compared. The blood lymphocytes of cerebral infarction were cultured before and after treatment. After that, the mitosis index (MI), cell kinetics index (CKI), sister-chromatid exchanges (SCE) frequencies and apoptosis were determined. Results The therapeutic group was better than the control one. The effective rate in the therapeutic group was 88.6%, in the control one was 65.7%. The viscosity and fibrinogen, etc were better than that in the control group with significant difference (P<0.01). The lymphocyte proliferation index was significantly two increased than the control one (P>0.05) in cerebral infarction patients after treatment; The CKI of lymphocytes had no obvious difference among groups (P>0.05) SCE frequencies of lymphocytes had no statistic significance between control group and ILLLI on (P>0.05). It showed the apoptosis rate of lymphocytes in cerebral infarction patients after ILLLI treatment increased significantly compared with the control group, (P<0.001). There was a significant difference of apoptosis rate of lymphocytes in cerebral infarction patients than the control (P<0.001). Conclusions: During the He-Ne laser intravascular irradiation of the cerebral infarction, the low level He-Ne by ILLLI can increase the proliferation of lymphocytes, and can induce lymphocytes to apoptosis, but has no mutagenicity of cells.

  17. [Evaluation of the severity course and prognosis of disseminated intravascular blood coagulation syndrome].

    PubMed

    Kinakh, M V; Chaplyk, V V; Fedchyshyn, N R

    2009-01-01

    Activation of the peroxidal oxidation of lipids (POL) processes with its primary and secondary products levels raising constitutes a favourable sign, according to data of examination of 66 patients, suffering different phases of disseminated intravascular blood coagulation syndrome (DIBCS). The POL products contents reduction (areactive course) characterizes the process severity and constitutes an unfavourable prognostical sign. The areactive course rate is the highest in the patients, suffering DIBCS, phase III.

  18. Isolated Intravascular Large B-cell Lymphoma Presenting with Diffuse Ground Glass Pulmonary Infiltrates.

    PubMed

    Srivali, Narat; Pannu, Bibek S; Iyer, Vivek N

    2016-06-01

    A case of 44-year-old man with dyspnea and CT chest demonstrated bilateral infiltration. Patient was failed to improve with antibiotics and steroid. Finally, video-assisted thoracic surgery-guided lung biopsy was performed and surprisingly revealed intravascular large B cell lymphoma. The patient was subsequently started on chemotherapy with considerable clinical improvement. At the time of last follow-up (4 years from diagnosis); there was no clinical or radiologic evidence of tumor recurrence. PMID:27408440

  19. Temporal relationship between prostate brachytherapy and the diagnosis of colorectal cancer

    SciTech Connect

    Gutman, Sarah A.; Merrick, Gregory S. . E-mail: gmerrick@urologicresearchinstitute.org; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Galbreath, Robert W.; Adamovich, Edward

    2006-09-01

    Purpose: To identify the location of pretreatment and posttreatment colorectal malignancies and posttreatment colorectal polyps in patients with clinically localized prostate cancer managed with brachytherapy. Methods and Materials: From April 1995 through July 2004, 1,351 consecutive patients underwent brachytherapy for clinical stage T1b-T3a (American Joint Committee on Cancer, 2002) prostate cancer. Supplemental external beam radiotherapy (XRT) was administered to 699 patients. The median follow-up was 4.6 years. Operative and pathology reports were reviewed for all patients with pretreatment and posttreatment colorectal cancer and posttreatment colorectal polyps. Multiple parameters were evaluated for the development of colorectal cancer or colorectal polyps. Results: Colorectal cancer was diagnosed in 23 and 25 patients before and after prostate brachytherapy, respectively. No differences were identified in the distribution of colorectal cancers either before or after treatment (3 and 4 rectal cancers in the pre- and postbrachytherapy cohorts). Thirty-five of the 48 colorectal cancers (73%) were diagnosed within 5 years of brachytherapy with a peak incidence 1 year after brachytherapy. One hundred ninety-two colorectal polyps were diagnosed after brachytherapy, 160 (83%) occurred within 4 years of brachytherapy, and only 27 (14%) were located in the rectum. In multivariate Cox regression analysis, prostate D{sub 9} (minimum percentage of the dose covering 90% of the target volume) predicted for posttreatment colorectal cancer. Rectal polyps were most closely related to patient age and percent positive biopsies, whereas sigmoid/colon polyps were best predicted by patient age, planning volume, and supplemental XRT. Conclusions: Colorectal cancer was diagnosed with equal frequency before and after brachytherapy with comparable geographic distributions. In addition, the vast majority of postbrachytherapy colorectal polyps were located beyond the confines of the

  20. High Dose-Rate Versus Low Dose-Rate Brachytherapy for Lip Cancer

    SciTech Connect

    Ghadjar, Pirus; Bojaxhiu, Beat; Simcock, Mathew; Terribilini, Dario; Isaak, Bernhard; Gut, Philipp; Wolfensberger, Patrick; Broemme, Jens O.; Geretschlaeger, Andreas; Behrensmeier, Frank; Pica, Alessia; Aebersold, Daniel M.

    2012-07-15

    Purpose: To analyze the outcome after low-dose-rate (LDR) or high-dose-rate (HDR) brachytherapy for lip cancer. Methods and Materials: One hundred and three patients with newly diagnosed squamous cell carcinoma of the lip were treated between March 1985 and June 2009 either by HDR (n = 33) or LDR brachytherapy (n = 70). Sixty-eight patients received brachytherapy alone, and 35 received tumor excision followed by brachytherapy because of positive resection margins. Acute and late toxicity was assessed according to the Common Terminology Criteria for Adverse Events 3.0. Results: Median follow-up was 3.1 years (range, 0.3-23 years). Clinical and pathological variables did not differ significantly between groups. At 5 years, local recurrence-free survival, regional recurrence-free survival, and overall survival rates were 93%, 90%, and 77%. There was no significant difference for these endpoints when HDR was compared with LDR brachytherapy. Forty-two of 103 patients (41%) experienced acute Grade 2 and 57 of 103 patients (55%) experienced acute Grade 3 toxicity. Late Grade 1 toxicity was experienced by 34 of 103 patients (33%), and 5 of 103 patients (5%) experienced late Grade 2 toxicity; no Grade 3 late toxicity was observed. Acute and late toxicity rates were not significantly different between HDR and LDR brachytherapy. Conclusions: As treatment for lip cancer, HDR and LDR brachytherapy have comparable locoregional control and acute and late toxicity rates. HDR brachytherapy for lip cancer seems to be an effective treatment with acceptable toxicity.

  1. Effect of brachytherapy technique and patient characteristics on cervical cancer implant dosimetry

    SciTech Connect

    Anker, Christopher J.; O'Donnell, Kristen; Boucher, Kenneth M.; Gaffney, David K.

    2013-01-01

    Our purpose was to evaluate the relationship between brachytherapy technique and patient characteristics on dose to organs-at-risk (OARs) in patients undergoing high dose rate (HDR) brachytherapy for cervical cancer. From 1998 to 2008, 31 patients with cervical cancer with full dosimetric data were identified who received definitive external-beam radiation and HDR brachytherapy with tandem and ovoid applicators. Doses were recorded at point A, the International Commission on Radiation Units and Measurements (ICRU)-38 rectal point, the ICRU-38 bladder point, the vaginal surface, and the pelvic sidewall. Generalized estimating equations were used to determine the significance of changes in OAR to point A dose ratios with differences in brachytherapy technique or patient characteristics. Patients underwent a median of 5 brachytherapy procedures (range, 3 to 5), with a total of 179 procedures for 31 patients. For all brachytherapy treatments, the average ratios between the doses for the rectal, bladder, vaginal surface, and pelvic sidewall reference points to those at point A were 0.49, 0.59, 1.15, and 0.17, respectively. In general, decreased OAR dose was associated with a lower stage, younger age, increased ovoid size, increased tandem length, and earlier implant number. Increased tandem curvature significantly increased bladder dose and decreased rectal dose. Intravenous anesthesia usage was not correlated with improved dosimetry. This study allowed identification of patient and procedure characteristics influencing OAR dosing. Although the advent of 3-dimensional (3D) image-guided brachytherapy will bring new advances in treatment optimization, the actual technique involved at the time of the brachytherapy implant procedure will remain important.

  2. Prostate Brachytherapy seed migration to the Bladder presenting with Gross Hematuria.

    PubMed

    Haroun, Reham R; Nance, John W; Fishman, Elliot K

    2016-01-01

    We present the radiologic findings in a case of prostate brachytherapy seed migration to the bladder presenting as gross hematuria. While prostate brachytherapy seed implantation is considered a relatively safe procedure, migration is not uncommon; however, it is usually clinically silent and the seeds most commonly migrate to the lungs through the venous circulation via the periprostatic venous plexus. Our case illustrates that local erosion is possible, can be symptomatic, and therefore must be considered when evaluating select patients. PMID:27200152

  3. Prostate Brachytherapy seed migration to the Bladder presenting with Gross Hematuria

    PubMed Central

    Haroun, Reham R; Nance, John W; Fishman, Elliot K

    2016-01-01

    We present the radiologic findings in a case of prostate brachytherapy seed migration to the bladder presenting as gross hematuria. While prostate brachytherapy seed implantation is considered a relatively safe procedure, migration is not uncommon; however, it is usually clinically silent and the seeds most commonly migrate to the lungs through the venous circulation via the periprostatic venous plexus. Our case illustrates that local erosion is possible, can be symptomatic, and therefore must be considered when evaluating select patients. PMID:27200152

  4. Lead-free intravascular ultrasound transducer using BZT-50BCT ceramics.

    PubMed

    Yan, Xingwei; Lam, Kwok Ho; Li, Xiang; Chen, Ruimin; Ren, Wei; Ren, Xiaobing; Zhou, Qifa; Shung, K Kirk

    2013-06-01

    This paper reports the fabrication and evaluation of a high-frequency ultrasonic transducer based on a new lead-free piezoelectric material for intravascular imaging application. Lead-free 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO4(BZT-50BCT) ceramic with a high dielectric constant (~2800) was employed to develop a high-frequency (~30 MHz) needle-type ultrasonic transducer. With superior piezoelectric performance (piezoelectric coefficient d33 ~ 600 pC/N), the lead-free transducer was found to exhibit a -6-dB bandwidth of 53% with an insertion loss of 18.7 dB. In vitro intravascular ultrasound (IVUS) imaging of a human cadaver coronary artery was performed to demonstrate the potential of the lead-free transducer for biomedical imaging applications. This is the first time that a lead-free transducer has been used for IVUS imaging application. The experimental results suggest that the BZT-50BCT ceramic is a promising lead-free piezoelectric material for high-frequency intravascular imaging applications.

  5. Lead-Free Intravascular Ultrasound Transducer Using BZT-50BCT Ceramics

    PubMed Central

    Yan, Xingwei; Lam, Kwok Ho; Li, Xiang; Chen, Ruimin; Ren, Wei; Ren, Xiaobing; Zhou, Qifa; Shung, K. Kirk

    2013-01-01

    This paper reports the fabrication and evaluation of a high-frequency ultrasonic transducer based on a new lead-free piezoelectric material for intravascular imaging application. Lead-free 0.5Ba(Zr0.2Ti0.8)O3−0.5(Ba0.7Ca0.3)TiO3 (BZT-50BCT) ceramic with a high dielectric constant (~2800) was employed to develop a high-frequency (~30 MHz) needle-type ultrasonic transducer. With superior piezoelectric performance (piezoelectric coefficient d33 ~ 600 pC/N), the lead-free transducer was found to exhibit a −6-dB bandwidth of 53% with an insertion loss of 18.7 dB. In vitro intravascular ultrasound (IVUS) imaging of a human cadaver coronary artery was performed to demonstrate the potential of the lead-free transducer for biomedical imaging applications. This is the first time that a lead-free transducer has been used for IVUS imaging application. The experimental results suggest that the BZT-50BCT ceramic is a promising lead-free piezoelectric material for high-frequency intravascular imaging applications. PMID:25004492

  6. The intravascular low level laser irradiation (ILLLI) in treatment of psoriasis clinically

    NASA Astrophysics Data System (ADS)

    Zhu, Jing; Nie, Fan; Shi, Hong-Min

    2005-07-01

    Objective: The title is research curative effect of intravascular low level laser irradiation (ILLLI) in treatment of psoriasis. Method: 478 patients with psoriasis from five groups to observe their efficacy. Group1 were treated by He-Ne laser combined with drug. Group 2 were treated by semi-conductor laser combined with drug. Group 3 were treated only by He-He laser. Group 4 were treated by semi-conductor laser. Group 5 were treated only by drug. The Ridit statistical analysis was applied to all of these data. The treatment of intravascular low level laser irradiation is as follow: laser power:4-5mw, 1 hour per day and 10 days as a period combined with vit C 2.0 g iv and inhalation of O2. Results: The clinical results: the near efficient rate was 100%, in group1-4, if combined with drugs it would be better. Ridit statistical analysis showed no significant difference between group1-4, p>0.05. The efficient rate 72.97% in group5.There were showed very significant difference with group1-4, p<0.01. 2.There were no significant differences between He-Ne laser (632.8nm) and semiconductor laser(650nm); 3.The efficacy of ILLLI in psoriasis was positive correlation to the ILLLI times. Conclusions: It can improve curative effect of intravascular low levellaser irradiation (ILLLI) in treatment of psoriasis.

  7. Stochastic bifurcation characteristics of SMA intravascular stent subjected to radial and axial excitations.

    PubMed

    Zhu, Zhiwen; Zhang, Wendi; Xu, Jia

    2014-01-01

    A kind of shape memory alloy (SMA) hysteretic nonlinear model is developed, and the stochastic bifurcation characteristics of SMA intravascular stents subjected to radial and axial excitations are studied in this paper. A new nonlinear differential item is introduced to interpret the hysteretic phenomena of SMA strain-stress curves, and the dynamic model of SMA intravascular stent subjected to radial and axial stochastic excitations is established. The conditions of the system's stochastic stability are determined, and the probability density function of the system response is obtained. Finally, the stochastic Hopf bifurcation characteristics of the system are analyzed. Theoretical analysis and numerical simulation show that the system stability varies with bifurcation parameters, and stochastic Hopf bifurcation occurs in the process; there are two limit cycles in the stationary probability density of the system response in some cases, which means that there are two vibration amplitudes whose probability are both very high; jumping phenomena between the two vibration amplitudes appears with the change of conditions, which may cause stent fracture or loss. The results of this paper are helpful for application of SMA intravascular stent in biomedical engineering fields.

  8. The neuroprotective effects of intravascular low level laser irradiation on cerebral ischemia rats

    NASA Astrophysics Data System (ADS)

    Qiu, Yongming; Lu, Zhaofeng; Wang, Zhongguang; Jiang, Jiyao

    2005-07-01

    The effects of intravascular low level laser irradiation of He-Ne on rat MCAo-induced cerebral injury were studied. The results showed that control rats (subjected to MCAo injury without laser treatment) at 7d exhibited striatal and cortical brain infarction in the right hemisphere from approximately 3 to 11mm from the front pole. the total infarct volume in this group was 34.5+/-8.1mm3. For experimental rats (with laser management), the total infarct volume was 29.0+/-9.0mm3. P was gained less than 0.05. The neurological score of control group was 4.7+/-0.6 and it was 5.2+/-1.0 in experimental group, comparison by statistical analysis showed P less than 0.05. The cerebral pathological damages in the control group were more severe than in experimental group. We concluded that the intravascular low level laser irradiation has no remarked complication and is helpful to reduce ischemic damage. There is clinically potential for the application of intravascular He-Ne low level laser irradiation in ischemia stroke.

  9. Use of an oxygen-carrying blood substitute to improve intravascular optical coherence tomography imaging

    NASA Astrophysics Data System (ADS)

    Hoang, Khiet C.; Edris, Ahmad; Su, Jianping; Mukai, David S.; Mahon, Sari; Petrov, Artiom D.; Kern, Morton; Ashan, Chowdhury; Chen, Zhongping; Tromberg, Bruce J.; Narula, Jagat; Brenner, Matthew

    2009-05-01

    Optical coherence tomography (OCT) is a catheter-based imaging technology with powerful resolution capable of identifying vulnerable plaques and guiding coronary intervention. However, a significant limitation of intravascular OCT imaging is its attenuation by blood. We propose that the use of an oxygen-carrying blood substitute could potentially optimize OCT image quality. Surgical isolation of the descending thoracic aorta of six rabbits is performed, followed by intravascular OCT imaging of the abdominal aorta. Perfluorodecalin (PFD) is oxygenated using a bubble-through technique with 100% oxygen. OCT imaging is performed and compared using three different flushing modalities: PFD; saline; and blood. OCT imaging of the rabbit abdominal aorta is successful in all of the subjects. In each of the six studied subjects, flushing with PFD consistently provides dramatically better imaging of the vessel wall tissue structures. OCT image quality is highly dependent on the ability of the flushing modality to remove blood from the imaging field. From this proof-of-concept study, we demonstrate that endovascular flushing with an oxygen-carrying blood substitute (PFD) is optically superior to saline flushing for intravascular imaging.

  10. A novel dual-frequency imaging method for intravascular ultrasound applications.

    PubMed

    Qiu, Weibao; Chen, Yan; Wong, Chi-Man; Liu, Baoqiang; Dai, Jiyan; Zheng, Hairong

    2015-03-01

    Intravascular ultrasound (IVUS), which is able to delineate internal structures of vessel wall with fine spatial resolution, has greatly enriched the knowledge of coronary atherosclerosis. A novel dual-frequency imaging method is proposed in this paper for intravascular imaging applications. A probe combined two ultrasonic transducer elements with different center frequencies (36 MHz and 78 MHz) is designed and fabricated with PMN-PT single crystal material. It has the ability to balance both imaging depth and resolution, which are important imaging parameters for clinical test. A dual-channel imaging platform is also proposed for real-time imaging, and this platform has been proven to support programmable processing algorithms, flexible imaging control, and raw RF data acquisition for IVUS applications. Testing results show that the -6 dB axial and lateral imaging resolutions of low-frequency ultrasound are 78 and 132 μm, respectively. In terms of high-frequency ultrasound, axial and lateral resolutions are determined to be as high as 34 and 106 μm. In vitro intravascular imaging on healthy swine aorta is conducted to demonstrate the performance of the dual-frequency imaging method for IVUS applications. PMID:25454093

  11. Development of an intravascular pumping oxygenator using a new silicone membrane.

    PubMed

    Sueda, T; Fukunaga, S; Morita, S; Sueshiro, M; Hirai, S; Okada, K; Orihashi, K; Matsuura, Y

    1997-01-01

    A new intravascular pumping oxygenator (IVPO) was developed for intravascular gas exchange and circulatory assistance in critically ill patients with respiratory and circulatory failure. The IVPO utilizes new silicone hollow fibers (diameter, 1 mm; membrane width, 50 microns) and consists of two driving tubes for the oxygenation and pumping of circulating blood. The performance characteristics of the IVPO were studied using an experiment ex vivo model. With a mean hemoglobin concentration of 10.5 +/- 2.3 g/dl, total oxygen transfer was 5.6 +/- 1.5 ml/min at a blood flow of 200 ml/min and 6.3 +/- 2.2 ml/min at a blood flow of 250 ml/min. Total CO2 transfer was 3.8 +/- 1.4 ml/min at a blood flow of 200 ml/min and 4.2 +/- 1.6 ml/min at a blood flow of 250 ml/min. Blood flow increased to a maximum of 250 ml/min during IVPO pumping. This preliminary experiment demonstrated that the IVPO has the capacity to function both as circulatory assist pump and as an intravascular hollow fiber oxygenator.

  12. Integrated intravascular ultrasound and optical-resolution photoacoustic microscopy with a 1-mm-diameter catheter

    NASA Astrophysics Data System (ADS)

    Bai, Xiaosong; Gong, Xiaojing; Lin, Riqiang; Hau, William; Song, Liang

    2014-03-01

    Intravascular ultrasound (IVUS) plays a vital role in assessing the severity of atherosclerosis and has greatly enriched our knowledge on atherosclerotic plaques. However, it mainly reveals the structural information of plaques. In contrast, spectroscopic and molecular photoacoustic imaging can potentially improve plaque composition identification, inflammation detection, and ultimately the stratification of plaque vulnerability and risk. In this work, we developed an integrated intravascular ultrasound and optical-resolution photoacoustic microscopy (IVUS-PAM) system with a single catheter as small as 1 mm in diameter, comparable to that of existing clinical IVUS catheters. In addition, by using a GRIN lens to focus the excitation laser pulse, the system provides an optical-diffraction limited photoacoustic lateral resolution as fine as 19.6 micrometers, ~10-fold finer than that of conventional intravascular photoacoustic imaging and existing IVUS technology. The system employs a custom-made miniaturized single-element ultrasonic transducer with a dimension of ~0.5 mm, a centre frequency of ~40 MHz, and a fractional bandwidth of ~60%. The IVUS-PAM can simultaneously acquire co-registered IVUS images with an axial resolution of ~40 micrometers and a lateral resolution of ~200 micrometers. In the future, IVUS-PAM may open up new opportunities for improved high-resolution vulnerable plaque imaging and image-guided stent deployment.

  13. Lead-free intravascular ultrasound transducer using BZT-50BCT ceramics.

    PubMed

    Yan, Xingwei; Lam, Kwok Ho; Li, Xiang; Chen, Ruimin; Ren, Wei; Ren, Xiaobing; Zhou, Qifa; Shung, K Kirk

    2013-06-01

    This paper reports the fabrication and evaluation of a high-frequency ultrasonic transducer based on a new lead-free piezoelectric material for intravascular imaging application. Lead-free 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO4(BZT-50BCT) ceramic with a high dielectric constant (~2800) was employed to develop a high-frequency (~30 MHz) needle-type ultrasonic transducer. With superior piezoelectric performance (piezoelectric coefficient d33 ~ 600 pC/N), the lead-free transducer was found to exhibit a -6-dB bandwidth of 53% with an insertion loss of 18.7 dB. In vitro intravascular ultrasound (IVUS) imaging of a human cadaver coronary artery was performed to demonstrate the potential of the lead-free transducer for biomedical imaging applications. This is the first time that a lead-free transducer has been used for IVUS imaging application. The experimental results suggest that the BZT-50BCT ceramic is a promising lead-free piezoelectric material for high-frequency intravascular imaging applications. PMID:25004492

  14. Adherence to Vaginal Dilation Following High Dose Rate Brachytherapy for Endometrial Cancer

    SciTech Connect

    Friedman, Lois C.; Abdallah, Rita; Schluchter, Mark; Panneerselvam, Ashok; Kunos, Charles A.

    2011-07-01

    Purpose: We report demographic, clinical, and psychosocial factors associated with adherence to vaginal dilation and describe the sexual and marital or nonmarital dyadic functioning of women following high dose rate (HDR) brachytherapy for endometrial cancer. Methods and Materials: We retrospectively evaluated women aged 18 years or older in whom early-stage endometrial (IAgr3-IIB) cancers were treated by HDR intravaginal brachytherapy within the past 3.5 years. Women with or without a sexual partner were eligible. Patients completed questionnaires by mail or by telephone assessing demographic and clinical variables, adherence to vaginal dilation, dyadic satisfaction, sexual functioning, and health beliefs. Results: Seventy-eight of 89 (88%) eligible women with early-stage endometrial cancer treated with HDR brachytherapy completed questionnaires. Only 33% of patients were adherers, based on reporting having used a dilator more than two times per week in the first month following radiation. Nonadherers who reported a perceived change in vaginal dimension following radiation reported that their vaginas were subjectively smaller after brachytherapy (p = 0.013). Adherers reported more worry about their sex lives or lack thereof than nonadherers (p = 0.047). Patients reported considerable sexual dysfunction following completion of HDR brachytherapy. Conclusions: Adherence to recommendations for vaginal dilator use following HDR brachytherapy for endometrial cancer is poor. Interventions designed to educate women about dilator use benefit may increase adherence. Although sexual functioning was compromised, it is likely that this existed before having cancer for many women in our study.

  15. WE-E-BRD-01: HDR Brachytherapy I: Overview of Clinical Application and QA

    SciTech Connect

    Libby, B; Showalter, T

    2014-06-15

    With the increased usage of high dose rate (HDR) brachytherapy and the introduction of dedicated image guided brachytherapy suites, it is necessary to review the processes and procedures associated with safely delivering these treatments in the expedited time scales that dedicated treatment suites afford. The speakers will present the clinical aspects of switching from LDR to HDR treatments, including guidelines for patient selection, and the clinical outcomes comparing LDR to HDR. The speakers will also discuss the HDR treatment process itself, because the shortened clinical timeline involved with a streamlined scan/plan/treat workflow can introduce other issues. Safety and QA aspects involved with the streamlined process, including increased personnel required for parallel tasks, and possible interfering tasks causing delays in patient treatments will also be discussed. Learning Objectives: To understand the clinical aspects of HDR Brachytherapy, including common clinical indications, patient selection, and the evolving evidence in support of this therapeutic modality To review the current prominent clinical trials for HDR brachytherapy To interpret the established guidelines for HDR brachytherapy quality assurance for implementation into practical clinical settings. To introduce the basic requirements for image guided brachytherapy.

  16. Dosimetric equivalence of nonstandard HDR brachytherapy catheter patterns

    SciTech Connect

    Cunha, J. A. M.; Hsu, I-C.; Pouliot, J.

    2009-01-15

    Purpose: To determine whether alternative high dose rate prostate brachytherapy catheter patterns can result in similar or improved dose distributions while providing better access and reducing trauma. Materials and Methods: Standard prostate cancer high dose rate brachytherapy uses a regular grid of parallel needle positions to guide the catheter insertion. This geometry does not easily allow the physician to avoid piercing the critical structures near the penile bulb nor does it provide position flexibility in the case of pubic arch interference. This study used CT datasets with 3 mm slice spacing from ten previously treated patients and digitized new catheters following three hypothetical catheter patterns: conical, bi-conical, and fireworks. The conical patterns were used to accommodate a robotic delivery using a single entry point. The bi-conical and fireworks patterns were specifically designed to avoid the critical structures near the penile bulb. For each catheter distribution, a plan was optimized with the inverse planning algorithm, IPSA, and compared with the plan used for treatment. Irrelevant of catheter geometry, a plan must fulfill the RTOG-0321 dose criteria for target dose coverage (V{sub 100}{sup Prostate}>90%) and organ-at-risk dose sparing (V{sub 75}{sup Bladder}<1 cc, V{sub 75}{sup Rectum}<1 cc, V{sub 125}{sup Urethra}<<1 cc). Results: The three nonstandard catheter patterns used 16 nonparallel, straight divergent catheters, with entry points in the perineum. Thirty plans from ten patients with prostate sizes ranging from 26 to 89 cc were optimized. All nonstandard patterns fulfilled the RTOG criteria when the clinical plan did. In some cases, the dose distribution was improved by better sparing the organs-at-risk. Conclusion: Alternative catheter patterns can provide the physician with additional ways to treat patients previously considered unsuited for brachytherapy treatment (pubic arch interference) and facilitate robotic guidance of

  17. Tissue modeling schemes in low energy breast brachytherapy.

    PubMed

    Afsharpour, Hossein; Landry, Guillaume; Reniers, Brigitte; Pignol, Jean-Philippe; Beaulieu, Luc; Verhaegen, Frank

    2011-11-21

    Breast tissue is heterogeneous and is mainly composed of glandular (G) and adipose (A) tissues. The proportion of G versus A varies considerably among the population. The absorbed dose distributions in accelerated partial breast irradiation therapy with low energy photon brachytherapy sources are very sensitive to tissue heterogeneities. Current clinical algorithms use the recommendations of the AAPM TG43 report which approximates the human tissues by unit density water. The aim of this study is to investigate various breast tissue modeling schemes for low energy brachytherapy. A special case of breast permanent seed implant is considered here. Six modeling schemes are considered. Uniform and non-uniform water breast (UWB and NUWB) consider the density but neglect the effect of the composition of tissues. The uniform and the non-uniform G/A breast (UGAB and NUGAB) as well the age-dependent breast (ADB) models consider the effect of the composition. The segmented breast tissue (SBT) method uses a density threshold to distinguish between G and A tissues. The PTV D(90) metric is used for the analysis and is based on the dose to water (D(90(w,m))). D(90(m,m)) is also reported for comparison to D(90(w,m)). The two-month post-implant D(90(w,m)) averaged over 38 patients is smaller in NUWB than in UWB by about 4.6% on average (ranging from 5% to 13%). Large average differences of G/A breast models with TG43 (17% and 26% in UGAB and NUGAB, respectively) show that the effect of the chemical composition dominates the effect of the density on dose distributions. D(90(w,m)) is 12% larger in SBT than in TG43 when averaged. These differences can be as low as 4% or as high as 20% when the individual patients are considered. The high sensitivity of dosimetry on the modeling scheme argues in favor of an agreement on a standard tissue modeling approach to be used in low energy breast brachytherapy. SBT appears to generate the most geometrically reliable breast tissue models in this

  18. Primary Causes of Death After Permanent Prostate Brachytherapy

    SciTech Connect

    Bittner, Nathan; Merrick, Gregory S. Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Brammer, Sarah G.; Moyad, Mark

    2008-10-01

    Purpose: To evaluate the primary causes of death in low-risk (low-risk), intermediate-risk (intermediate-risk), and high-risk (high-risk) patients undergoing permanent prostate brachytherapy with or without supplemental therapies. Methods and Materials: From April 1995 through November 2004, a total of 1,354 consecutive patients underwent prostate brachytherapy. All patients underwent brachytherapy >3 years before analysis. Of the patients, 532 (39.3%) received androgen deprivation therapy and 703 (51.9%) received supplemental radiation therapy. The median follow-up was 5.4 years. Multiple parameters were evaluated as predictors of cause-specific, biochemical progression-free, and overall survival. Results: The 10-year cause-specific survival was 97.0% (99.7%, 99.0%, and 90.1% for low-risk, intermediate-risk, and high-risk patients). Overall survival was 76.7% (82.5%, 78.3%, and 67.6% for low-, intermediate-, and high-risk patients, respectively). The cumulative death rate for cardiovascular disease was 11.5% (8.7%, 9.3%, and 19.8% for low-, intermediate-, and high-risk patients). The death rate from second malignancies (nonprostate cancer) was 7.2% and was not substantially different when stratified by risk group. Death from all other causes was 6.5% for the entire cohort but 1.3%, 5.0%, and 10.8% for low-, intermediate-, and high-risk patients. In multivariate analysis, death from prostate cancer was best predicted by Gleason score and risk group, whereas death from cardiovascular disease, nonprostate cancer, and all other causes were most closely related to patient age and tobacco use. Conclusions: Although cardiovascular mortality was the predominant cause of death, prostate cancer was responsible for approximately 10% of all deaths. In particular, overall survival was poorest in the high-risk group. Although high-risk patients were most likely to die of prostate cancer, the divergence in overall survival between high-risk and lower-risk patients primarily

  19. Critical Organ Preservation in Reirradiation Brachytherapy by Injectable Spacer

    SciTech Connect

    Kishi, Kazushi Sonomura, Tetsuo; Shirai, Shintaro; Sato, Morio; Tanaka, Kayo

    2009-10-01

    Purpose: This case series study evaluated the feasibility and effectiveness of an interstitial high-dose rate brachytherapy (HDR-BT) procedure combined with an at-risk organ-sparing procedure. Methods and Materials: Thirty patients who were scheduled for reirradiation treatment for recurrent cancer after receiving a median dose of 60 Gy (range, 44-70 Gy) in 2-Gy fractions of previous external beam treatment were enrolled. Thirteen patients had lesions in the head and neck, and other lesions were located in the axilla, skeleton, breast, pelvis, and abdominal wall. Chief complaints included local masses (for 25) and refractory pain (for 21). After high-dose rate brachytherapy applicator needle implantation, an optimal CT-based three-dimensional brachytherapy plan was created with a virtual at-risk organ shift from the target. According to the plan, hyaluronic acid gel was injected to maintain the shift during irradiation. The prescribed dose was the result of an individualized tradeoff between target dose and at-risk organ dose, to avoid serious complications. A single-fraction dose of 18.0 Gy (median, equivalent to 75.6 Gy at an {alpha}/{beta} value of 3; range, 16-20 Gy) was applied to the tumor. Results: The at-risk organ dose decreased from 9.1 {+-} 0.9 Gy to 4.4 {+-} 0.4 Gy (mean {+-} standard deviation, p < 0.01), and the normal tissue complication probability decreased from 60.8% {+-} 12.6% to 16.1% {+-} 19.8% (p < 0.01). The shift effect lasted at least 4 hours and disappeared gradually. Distinct tumor shrinkage in 20 of 21 eligible patients, including tumor disappearance in 6 patients, pain reduction in 18 of 21 eligible patients, and no unexpected late toxicity greater than grade 2 were observed during the 19.5-month observation period. Conclusions: This at-risk organ-sparing preservation procedure may provide a safe and efficient reirradiation treatment.

  20. [Role of the technician in a brachytherapy department].

    PubMed

    Bélot-Cheval, V; Lemoine, L; Cuisinier, C; Gensse, M-C; Lasbareilles, O

    2013-04-01

    The role of the technician in a brachytherapy department is essential for the cohesion of the treatment team made up of the radiation oncologist, the physicist, and the technician. He/she collaborates in the different treatment steps such as taking care of the patients, training of the professionals and research studies in collaboration with the team. He participates in all steps of the treatment such as preparation, technician's consultation, catheters/templates and radioactives sources implant, dose distribution analysis and treatment. He looks after the management of planning, radioactive sources and chemist's equipments. He takes part in the training of the junior technician, and support doctors and physicists in different studies. The procedure writing and the presentation of professional practices are also part of the technician task.

  1. [Palliative locoregional therapy for hilar cholangiocarcinoma: photodynamic therapy and brachytherapy].

    PubMed

    Dumoulin, F L; Horst, E; Sauerbruch, T; Gerhardt, T

    2007-08-01

    In hilar cholangiocarcinoma, only 20-30% of the patients are candidates for curative surgical resection, leaving the majority with merely palliative treatment options. Since the natural history of hilar cholangiocarcinoma is dominated by local complications rather than metastatic disease, local palliative treatment seems a reasonable option. Here, endoluminal photodynamic therapy has emerged as a promising treatment with several prospective observational studies and 2 prospective randomised studies published which included nearly 200 patients. With low complication rate and morbidity, PDT achieves an increased median survival as well as an increased quality of life even in patients with reduced performance status. Radiotherapy is an alternative local treatment option applied as brachytherapy, external beam radiotherapy or combined modality treatment. To date, however, sufficient data from controlled clinical trials are lacking, thus palliative radiotherapy has to be considered an experimental treatment option.

  2. Evaluating the cost of therapy for restenosis: considerations for brachytherapy.

    PubMed

    Weintraub, W S

    1996-11-01

    Costs have become increasingly important in medicine in recent years as demand for services has outstripped readily available resources. Clinical microeconomics offers an approach to understanding cost and outcomes in an environment of economic scarcity. In this article the types of costs and methods for determining cost are presented. In addition, methods for assessing outcome and outcome in relation to cost are developed. Restenosis after coronary angioplasty is a prime example of a clinical problem requiring economic evaluation. This is because it results in little serious morbidity except for recurrent chest pain, but it has serious economic consequences which occur some time after the original angioplasty. This makes the economic assessment of restenosis complicated. The application of health care microeconomic principles to brachytherapy for restenosis in the coronary arteries is presented. PMID:8960526

  3. Registration of structurally dissimilar images in MRI-based brachytherapy

    NASA Astrophysics Data System (ADS)

    Berendsen, F. F.; Kotte, A. N. T. J.; de Leeuw, A. A. C.; Jürgenliemk-Schulz, I. M.; Viergever, M. A.; Pluim, J. P. W.

    2014-08-01

    A serious challenge in image registration is the accurate alignment of two images in which a certain structure is present in only one of the two. Such topological changes are problematic for conventional non-rigid registration algorithms. We propose to incorporate in a conventional free-form registration framework a geometrical penalty term that minimizes the volume of the missing structure in one image. We demonstrate our method on cervical MR images for brachytherapy. The intrapatient registration problem involves one image in which a therapy applicator is present and one in which it is not. By including the penalty term, a substantial improvement in the surface distance to the gold standard anatomical position and the residual volume of the applicator void are obtained. Registration of neighboring structures, i.e. the rectum and the bladder is generally improved as well, albeit to a lesser degree.

  4. Apparatus and method for high dose rate brachytherapy radiation treatment

    DOEpatents

    Macey, Daniel J.; Majewski, Stanislaw; Weisenberger, Andrew G.; Smith, Mark Frederick; Kross, Brian James

    2005-01-25

    A method and apparatus for the in vivo location and tracking of a radioactive seed source during and after brachytherapy treatment. The method comprises obtaining multiple views of the seed source in a living organism using: 1) a single PSPMT detector that is exposed through a multiplicity of pinholes thereby obtaining a plurality of images from a single angle; 2) a single PSPMT detector that may obtain an image through a single pinhole or a plurality of pinholes from a plurality of angles through movement of the detector; or 3) a plurality of PSPMT detectors that obtain a plurality of views from different angles simultaneously or virtually simultaneously. The plurality of images obtained from these various techniques, through angular displacement of the various acquired images, provide the information required to generate the three dimensional images needed to define the location of the radioactive seed source within the body of the living organism.

  5. Radiobiological evaluation of low dose-rate prostate brachytherapy implants

    NASA Astrophysics Data System (ADS)

    Knaup, Courtney James

    Low dose-rate brachytherapy is a radiation therapy treatment for men with prostate cancer. While this treatment is common, the use of isotopes with varying dosimetric characteristics means that the prescription level and normal organ tolerances vary. Additionally, factors such as prostate edema, seed loss and seed migration may alter the dose distribution within the prostate. The goal of this work is to develop a radiobiological response tool based on spatial dose information which may be used to aid in treatment planning, post-implant evaluation and determination of the effects of prostate edema and seed migration. Aim 1: Evaluation of post-implant prostate edema and its dosimetric and biological effects. Aim 2: Incorporation of biological response to simplify post-implant evaluation. Aim 3: Incorporation of biological response to simplify treatment plan comparison. Aim 4: Radiobiologically based comparison of single and dual-isotope implants. Aim 5: Determine the dosimetric and radiobiological effects of seed disappearance and migration.

  6. Dose verification of eye plaque brachytherapy using spectroscopic dosimetry.

    PubMed

    Jarema, T; Cutajar, D; Weaver, M; Petasecca, M; Lerch, M; Kejda, A; Rosenfeld, A

    2016-09-01

    Eye plaque brachytherapy has been developed and refined for the last 80 years, demonstrating effective results in the treatment of ocular malignancies. Current dosimetry techniques for eye plaque brachytherapy (such as TLD- and film-based techniques) are time consuming and cannot be used prior to treatment in a sterile environment. The measurement of the expected dose distribution within the eye, prior to insertion within the clinical setting, would be advantageous, as any errors in source loading will lead to an erroneous dose distribution and inferior treatment outcomes. This study investigated the use of spectroscopic dosimetry techniques for real-time quality assurance of I-125 based eye plaques, immediately prior to insertion. A silicon detector based probe, operating in spectroscopy mode was constructed, containing a small (1 mm(3)) silicon detector, mounted within a ceramic holder, all encapsulated within a rubber sheath to prevent water infiltration of the electronics. Preliminary tests of the prototype demonstrated that the depth dose distribution through the central axis of an I-125 based eye plaque may be determined from AAPM Task Group 43 recommendations to a deviation of 6 % at 3 mm depth, 7 % at 5 mm depth, 1 % at 10 mm depth and 13 % at 20 mm depth, with the deviations attributed to the construction of the probe. A new probe design aims to reduce these discrepancies, however the concept of spectroscopic dosimetry shows great promise for use in eye plaque quality assurance in the clinical setting.

  7. Comparison of biochemical failure definitions for permanent prostate brachytherapy

    SciTech Connect

    Kuban, Deborah A. . E-mail: dakuban@mdanderson.org; Levy, Larry B.; Potters, Louis; Beyer, David C.; Blasko, John C.; Moran, Brian J.; Ciezki, Jay P.; Zietman, Anthony L.; Zelefsky, Michael J.; Pisansky, Thomas M.; Elshaikh, Mohamed; Horwitz, Eric M.

    2006-08-01

    Purpose: To assess prostate-specific antigen (PSA) failure definitions for patients with Stage T1-T2 prostate cancer treated by permanent prostate brachytherapy. Methods and Materials: A total of 2,693 patients treated with radioisotopic implant as solitary treatment for T1-T2 prostatic adenocarcinoma were studied. All patients had a pretreatment PSA, were treated at least 5 years before analysis, 1988 to 1998, and did not receive hormonal therapy before recurrence. Multiple PSA failure definitions were tested for their ability to predict clinical failure. Results: Definitions which determined failure by a certain increment of PSA rise above the lowest PSA level to date (nadir + x ng/mL) were more sensitive and specific than failure definitions based on PSA doubling time or a certain number of PSA rises. The sensitivity and specificity for the nadir + 2 definition were 72% and 83%, vs. 51% and 81% for 3 PSA rises. The surgical type definitions (PSA exceeding an absolute value) could match this sensitivity and specificity but only when failure was defined as exceeding a PSA level in the 1-3 ng/mL range and only when patients were allowed adequate time to nadir. When failure definitions were compared by time varying covariate regression analysis, nadir + 2 ng/mL retained the best fit. Conclusions: For patients treated by permanent radioisotopic implant for prostate cancer, the definition nadir + 2 ng/mL provides the best surrogate for failure throughout the entire follow-up period, similar to patients treated by external beam radiotherapy. Therefore, the same PSA failure definition could be used for both modalities. For brachytherapy patients with long-term follow-up, at least 6 years, defining failure as exceeding an absolute PSA level in the 0.5 ng/mL range may be reasonable.

  8. Dosimetry of the 198Au Source used in Interstitial Brachytherapy

    SciTech Connect

    Dauffy, L; Braby, L; Berner, B

    2004-05-18

    The American Association of Physicists in Medicine Task Group 43 report, AAPM TG-43, provides an analytical model and a dosimetry protocol for brachytherapy dose calculations, as well as documentation and results for some sealed sources. The radionuclide {sup 198}Au (T{sub 1/2} = 2.70 days, E{gamma} = 412 keV) has been used in the form of seeds for brachytherapy treatments including brain, eye, and prostate tumors. However, the TG-43 report has no data for {sup 198}Au seeds, and none have previously been obtained. For that reason, and because of the conversion of most treatment planning systems to TG-43 based methods, both Monte Carlo calculations (MCNP 4C) and thermoluminescent dosimeters (TLDs) are used in this work to determine these data. The geometric variation in dose is measured using an array of TLDs in a solid water phantom, and the seed activity is determined using both a well ion chamber and a High Purity Germanium detector (HPGe). The results for air kerma strength, S{sub k}, per unit apparent activity, are 2.06 (MCNP) and 2.09 (measured) U mCi{sup -1}. The former is identical to what was published in 1991 in the AAPM Task Group 32 report. The dose rate constant results, {Lambda}, are 1.12 (MCNP) and 1.10 (measured), cGy h{sup -1} U{sup -1}. The radial dose function, g(r), anisotropy function, F(r,{theta}), and anisotropy factor, {psi}{sub an}(r), are given. The anisotropy constant values are 0.973 (MCNP) and 0.994 (measured) and are consistent with both source geometry and the emitted photon energy.

  9. Monte Carlo dosimetry of a new 90Y brachytherapy source

    PubMed Central

    Junxiang, Wu; Shihu, You; Jing, Huang; Fengxiang, Long; Chengkai, Wang; Zhangwen, Wu; Qing, Hou

    2015-01-01

    Purpose In this study, we attempted to obtain full dosimetric data for a new 90Y brachytherapy source developed by the College of Chemistry (Sichuan University) for use in high-dose-rate after-loading systems. Material and methods The dosimetric data for this new source were used as required by the dose calculation formalisms proposed by the AAPM Task Group 60 and Task Group 149. The active core length of the new 90Y source was increased to 4.7 mm compared to the value of 2.5 mm for the old 90Sr/90Y source. The Monte Carlo simulation toolkit Geant4 was used to calculate these parameters. The source was located in a 30-cm-radius theoretical sphere water phantom. Results The dosimetric data included the reference absorbed dose rate, the radial dose function in the range of 1.0 to 8.0 mm in the longitudinal axis, and the anisotropy function with a θ in the range of 0° to 90° at 5° intervals and an r in the range of 1.0 to 8.0 mm in 0.2-mm intervals. The reference absorbed dose rate for the new 90Y source was determined to be equal to 1.6608 ± 0.0008 cGy s–1 mCi–1, compared to the values of 0.9063 ± 0.0005 cGy s–1 mCi–1 that were calculated for the old 90Sr/90Y source. A polynomial function was also obtained for the radial dose function by curve fitting. Conclusions Dosimetric data are provided for the new 90Y brachytherapy source. These data are meant to be used commercially in after-loading system. PMID:26622247

  10. Prostate brachytherapy postimplant dosimetry: Automatic plan reconstruction of stranded implants

    SciTech Connect

    Chng, N.; Spadinger, I.; Morris, W. J.; Usmani, N.; Salcudean, S.

    2011-01-15

    Purpose: Plan reconstruction for permanent implant prostate brachytherapy is the process of determining the correspondence between planned and implanted seeds in postimplant analysis. Plan reconstruction informs many areas of brachytherapy quality assurance, including the verification of seed segmentation, misplacement and migration assessment, implant simulations, and the dosimetry of mixed-activity or mixed-species implants. Methods: An algorithm has been developed for stranded implants which uses the interseed spacing constraints imposed by the suture to improve the accuracy of reconstruction. Seventy randomly selected clinical cases with a mean of 23.6 (range 18-30) needles and mean density of 2.0 (range 1.6-2.6) 2.0 (range 1.6-2.6) seeds/cm{sup 3} were automatically reconstructed and the accuracy compared to manual reconstructions performed using a custom 3D graphical interface. Results: Using the automatic algorithm, the mean accuracy of the assignment relative to manual reconstruction was found to be 97.7{+-}0.5%. Fifty-two of the 70 cases (74%) were error-free; of seeds in the remaining cases, 96.7{+-}0.3% were found to be attributed to the correct strand and 97.0{+-}0.3% were correctly connected to their neighbors. Any necessary manual correction using the interface is usually straightforward. For the clinical data set tested, neither the number of seeds or needles, average density, nor the presence of clusters was found to have an effect on reconstruction accuracy using this method. Conclusions: Routine plan reconstruction of stranded implants can be performed with a high degree of accuracy to support postimplant dosimetry and quality analyses.

  11. Brachytherapy dosimetry parameters calculated for a {sup 131}Cs source

    SciTech Connect

    Rivard, Mark J.

    2007-02-15

    A comprehensive analysis of the IsoRay Medical model CS-1 Rev2 {sup 131}Cs brachytherapy source was performed. Dose distributions were simulated using Monte Carlo methods (MCNP5) in liquid water, Solid{sup TM}, and Virtual Water{sup TM} spherical phantoms. From these results, the in-water brachytherapy dosimetry parameters have been determined, and were compared with those of Murphy et al. [Med. Phys. 31, 1529-1538 (2004)] using measurements and simulations. Our results suggest that calculations obtained using erroneous cross-section libraries should be discarded as recommended by the 2004 AAPM TG-43U1 report. Our {sub MC}{lambda} value of 1.046{+-}0.019 cGy h{sup -1} U{sup -1} is within 1.3% of that measured by Chen et al. [Med. Phys. 32, 3279-3285 (2005)] using TLDs and the calculated results of Wittman and Fisher [Med. Phys. 34, 49-54 (2007)] using MCNP5. Using the discretized energy approach of Rivard [Appl. Radiat. Isot. 55, 775-782 (2001)] to ascertain the impact of individual {sup 131}Cs photons on radial dose function and anisotropy functions, there was virtual equivalence of results for 29.461{<=}E{sub {gamma}}{<=}34.419 keV and for a mono-energetic 30.384 keV photon source. Comparisons of radial dose function and 2D anisotropy function data are also included, and an analysis of material composition and cross-section libraries was performed.

  12. GGEMS-Brachy: GPU GEant4-based Monte Carlo simulation for brachytherapy applications

    NASA Astrophysics Data System (ADS)

    Lemaréchal, Yannick; Bert, Julien; Falconnet, Claire; Després, Philippe; Valeri, Antoine; Schick, Ulrike; Pradier, Olivier; Garcia, Marie-Paule; Boussion, Nicolas; Visvikis, Dimitris

    2015-07-01

    In brachytherapy, plans are routinely calculated using the AAPM TG43 formalism which considers the patient as a simple water object. An accurate modeling of the physical processes considering patient heterogeneity using Monte Carlo simulation (MCS) methods is currently too time-consuming and computationally demanding to be routinely used. In this work we implemented and evaluated an accurate and fast MCS on Graphics Processing Units (GPU) for brachytherapy low dose rate (LDR) applications. A previously proposed Geant4 based MCS framework implemented on GPU (GGEMS) was extended to include a hybrid GPU navigator, allowing navigation within voxelized patient specific images and analytically modeled 125I seeds used in LDR brachytherapy. In addition, dose scoring based on track length estimator including uncertainty calculations was incorporated. The implemented GGEMS-brachy platform was validated using a comparison with Geant4 simulations and reference datasets. Finally, a comparative dosimetry study based on the current clinical standard (TG43) and the proposed platform was performed on twelve prostate cancer patients undergoing LDR brachytherapy. Considering patient 3D CT volumes of 400  × 250  × 65 voxels and an average of 58 implanted seeds, the mean patient dosimetry study run time for a 2% dose uncertainty was 9.35 s (≈500 ms 10-6 simulated particles) and 2.5 s when using one and four GPUs, respectively. The performance of the proposed GGEMS-brachy platform allows envisaging the use of Monte Carlo simulation based dosimetry studies in brachytherapy compatible with clinical practice. Although the proposed platform was evaluated for prostate cancer, it is equally applicable to other LDR brachytherapy clinical applications. Future extensions will allow its application in high dose rate brachytherapy applications.

  13. Comparison of external beam radiation and brachytherapy to external beam radiation alone for unresectable extrahepatic cholangiocarcinoma

    PubMed Central

    Boothe, Dustin; Hopkins, Zachary; Frandsen, Jonathan

    2016-01-01

    Background Extrahepatic cholangiocarcinoma (EHC) is a rare malignancy with a relatively poor prognosis. There are no randomized, prospective data to help define the optimal method of radiation delivery for unresectable EHC. The purpose of this study was to evaluate the benefit of adding brachytherapy to external beam radiation therapy (EBRT) for unresectable EHC. Methods A retrospective review of 1,326 patients with unresectable EHC using the Surveillance, Epidemiology, and End Results (SEER) database was completed. Kaplan-Meier methods were used to analyze the primary endpoint, overall survival. Univariate and multivariate analysis was performed to identify and control for potential confounding variables, including age at diagnosis, sex, stage, grade, histology, race, year of diagnosis, and reason for no surgery. Results Of the 1,326 patients with unresectable EHC, 1,188 (92.9%) received EBRT only, while 91 (7.1%) received both EBRT and brachytherapy. Patients receiving combined modality radiation therapy were more likely to be treated prior to the year 2000. Median overall survival for patients receiving EBRT and EBRT plus brachytherapy was 9 and 11 months, respectively (P=0.04). Cause specific survival was 12 months for those receiving EBRT only, and 15 months for those who received EBRT + brachytherapy (P=0.10). Survival analysis performed on patients with locoregional disease only revealed a trend towards prolonged overall survival with those receiving EBRT + brachytherapy (P=0.08). Multivariate analysis revealed grade and stage of disease were correlated with both overall survival and cause specific survival (P≤0.05). Conclusions Among patients with unresectable EHC, the addition of brachytherapy to EBRT is associated with a prolonged median overall survival. However, the use of brachytherapy boost decreased in the last decade of the study. PMID:27563448

  14. Combined therapy: surgery and intraoperative HDR brachytherapy for locally advanced and recurrent rectal cancer. Practical experience of Brachytherapy Department in Warsaw

    PubMed Central

    Radziszewski, Jakub; Lyczek, Jaroslaw; Kawczynska, Maria; Kulik, Anna

    2009-01-01

    Purpose Patients with locally advanced and recurrent rectal cancer have a dismal prognosis. The aim of proposed combined therapy – surgery and intraoperative brachytherapy, is to improve results of already applied methods and to define optimal group of patients for this treatment. We introduce practical experience of Brachytherapy Department in Cancer Centre – Institute in Warsaw. Material and methods Patients with primary T4NxM0 rectal cancer and isolated local pelvic recurrence were qualified for therapy. Between January 2005 and September 2008, 13 patients were included: 4 with primary cancer and 9 with recurrence, median age of 56. After surgical resection intraoperative radiotherapy was delivered with boost of high dose rate brachytherapy of 20Gy dose to the tumor bed. Results Primary point of the study is to evaluate impact of applied therapy on local control (LC), overall survival (OS) and disease free survival (DFS). Median follow-up is 16 months. Four of the patients died and 3 survivors are disease-free. There was no case of perioperative mortality. Conclusions A multimodality approach, using surgical resection with intra operative brachytherapy improves local control as well as patients survival in comparison with historical treatment group. Combined therapy is related to high morbidity, but low mortality. The preliminary observations seem to correspond with other authors data.

  15. Ischemia monitoring in off-pump coronary artery bypass surgery using intravascular near-infrared spectroscopy

    PubMed Central

    Bernet, Franziska H; Reineke, David; Zerkowski, Hans-Reinhard; Baykut, Doan

    2006-01-01

    Background In off-pump coronary artery bypass surgery, manipulations on the beating heart can lead to transient interruptions of myocardial oxygen supply, which can generate an accumulation of oxygen-dependent metabolites in coronary venous blood. The objective of this study was to evaluate the reliability of intravascular near-infrared spectroscopy as a monitoring method to detect possible ischemic events in off-pump coronary artery bypass procedures. Methods In 15 elective patients undergoing off-pump myocardial revascularization, intravascular near-infrared spectroscopic analysis of coronary venous blood was performed. NIR signals were transferred through a fiberoptic catheter for signal emission and collection. For data analysis and processing, a miniature spectrophotometer with multivariate statistical package was used. Signal acquisition and analysis were performed before and after revascularization. Spectroscopic data were compared with hemodynamic parameters, electrocardiogram, transesophageal echocardiography and laboratory findings. Results A conversion to extracorporeal circulation was not necessary. The mean number of grafts per patient was 3.1 ± 0.6. An intraoperative myocardial ischemia was not evident, as indicated by electrocardiogram and transesophageal echocardiography. Continuous spectroscopic analysis showed reproducible absorption spectra of coronary sinus blood. Due to uneventful intraoperative courses, clear ischemia-related changes could be detected in none of the patients. Conclusion Our initial results show that intravascular near-infrared spectroscopy can reliably be used for an online intraoperative ischemia monitoring in off-pump coronary artery bypass surgery. However, the method has to be further evaluated and standardized to determine the role of spectroscopy in off-pump coronary artery bypass surgery. PMID:16723014

  16. All-optical pulse-echo ultrasound probe for intravascular imaging (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Colchester, Richard J.; Noimark, Sacha; Mosse, Charles A.; Zhang, Edward Z.; Beard, Paul C.; Parkin, Ivan P.; Papakonstantinou, Ioannis; Desjardins, Adrien E.

    2016-02-01

    High frequency ultrasound probes such as intravascular ultrasound (IVUS) and intracardiac echocardiography (ICE) catheters can be invaluable for guiding minimally invasive medical procedures in cardiology such as coronary stent placement and ablation. With current-generation ultrasound probes, ultrasound is generated and received electrically. The complexities involved with fabricating these electrical probes can result in high costs that limit their clinical applicability. Additionally, it can be challenging to achieve wide transmission bandwidths and adequate wideband reception sensitivity with small piezoelectric elements. Optical methods for transmitting and receiving ultrasound are emerging as alternatives to their electrical counterparts. They offer several distinguishing advantages, including the potential to generate and detect the broadband ultrasound fields (tens of MHz) required for high resolution imaging. In this study, we developed a miniature, side-looking, pulse-echo ultrasound probe for intravascular imaging, with fibre-optic transmission and reception. The axial resolution was better than 70 microns, and the imaging depth in tissue was greater than 1 cm. Ultrasound transmission was performed by photoacoustic excitation of a carbon nanotube/polydimethylsiloxane composite material; ultrasound reception, with a fibre-optic Fabry-Perot cavity. Ex vivo tissue studies, which included healthy swine tissue and diseased human tissue, demonstrated the strong potential of this technique. To our knowledge, this is the first study to achieve an all-optical pulse-echo ultrasound probe for intravascular imaging. The potential for performing all-optical B-mode imaging (2D and 3D) with virtual arrays of transmit/receive elements, and hybrid imaging with pulse-echo ultrasound and photoacoustic sensing are discussed.

  17. Microparticle production, neutrophil activation, and intravascular bubbles following open-water SCUBA diving.

    PubMed

    Thom, Stephen R; Milovanova, Tatyana N; Bogush, Marina; Bhopale, Veena M; Yang, Ming; Bushmann, Kim; Pollock, Neal W; Ljubkovic, Marko; Denoble, Petar; Dujic, Zeljko

    2012-04-01

    The goal of this study was to evaluate annexin V-positive microparticles (MPs) and neutrophil activation in humans following decompression from open-water SCUBA diving with the hypothesis that changes are related to intravascular bubble formation. Sixteen male volunteer divers followed a uniform profile of four daily SCUBA dives to 18 m of sea water for 47 min. Blood was obtained prior to and at 80 min following the first and fourth dives to evaluate the impact of repetitive diving, and intravascular bubbles were quantified by trans-thoracic echocardiography carried out at 20-min intervals for 2 h after each dive. MPs increased by 3.4-fold after each dive, neutrophil activation occurred as assessed by surface expression of myeloperoxidase and the CD18 component of β(2)-integrins, and there was an increased presence of the platelet-derived CD41 protein on the neutrophil surface indicating interactions with platelet membranes. Intravascular bubbles were detected in all divers. Surprisingly, significant inverse correlations were found among postdiving bubble scores and MPs, most consistently at 80 min or more after the dive on the fourth day. There were significant positive correlations between MPs and platelet-neutrophil interactions after the first dive and between platelet-neutrophil interactions and neutrophil activation documented as an elevation in β(2)-integrin expression after the fourth dive. We conclude that MPs- and neutrophil-related events in humans are consistent with findings in an animal decompression model. Whether there are causal relationships among bubbles, MPs, platelet-neutrophil interactions, and neutrophil activation remains obscure and requires additional study.

  18. Intravascular ultrasonic-photoacoustic (IVUP) endoscope with 2.2-mm diameter catheter for medical imaging.

    PubMed

    Bui, Nhat Quang; Hlaing, Kyu Kyu; Nguyen, Van Phuc; Nguyen, Trung Hau; Oh, Yun-Ok; Fan, Xiao Feng; Lee, Yong Wook; Nam, Seung Yun; Kang, Hyun Wook; Oh, Junghwan

    2015-10-01

    Intravascular ultrasound (IVUS) imaging is extremely important for detection and characterization of high-risk atherosclerotic plaques as well as gastrointestinal diseases. Recently, intravascular photoacoustic (IVPA) imaging has been used to differentiate the composition of biological tissues with high optical contrast and ultrasonic resolution. The combination of these imaging techniques could provide morphological information and molecular screening to characterize abnormal tissues, which would help physicians to ensure vital therapeutic value and prognostic significance for patients before commencing therapy. In this study, integration of a high-frequency IVUS imaging catheter (45MHz, single-element, unfocused, 0.7mm in diameter) with a multi-mode optical fiber (0.6mm in core diameter, 0.22 NA), an integrated intravascular ultrasonic-photoacoustic (IVUP) imaging catheter, was developed to provide spatial and functional information on light distribution in a turbid sample. Simultaneously, IVUS imaging was co-registered to IVPA imaging to construct 3D volumetric sample images. In a phantom study, a polyvinyl alcohol (PVA) tissue-mimicking arterial vessel phantom with indocyanine green (ICG) and methylene blue (MB) inclusion was used to demonstrate the feasibility of mapping the biological dyes, which are used in cardiovascular and cancer diagnostics. For the ex vivo study, an excised sample of pig intestine with ICG was utilized to target the biomarkers present in the gastrointestinal tumors or the atherosclerotic plaques with the proposed hybrid technique. The results indicated that IVUP endoscope with the 2.2-mm diameter catheter could be a useful tool for medical imaging.

  19. Frequency-Domain Intravascular Optical Coherence Tomography of the Femoropopliteal Artery

    SciTech Connect

    Karnabatidis, Dimitris Katsanos, Konstantinos; Paraskevopoulos, Ioannis; Diamantopoulos, Athanasios; Spiliopoulos, Stavros; Siablis, Dimitris

    2011-12-15

    Purpose: Optical coherence tomography (OCT) is a catheter-based imaging method that employs near-infrared light to produce high-resolution intravascular images. The authors report the safety and feasibility and illustrate common imaging findings of frequency-domain OCT (FD-OCT) imaging of the femoropopliteal artery in a series of 20 patients who underwent infrainguinal angioplasty. Methods: After crossing the lesion of interest, OCT was performed with a dextrose saline flush technique with simultaneous obstructive manual groin compression. An automatic pullback FD-OCT device was employed (each scan acquiring 54 mm of vessel lumen in 271 consecutive frames). OCT images were acquired before and after balloon dilatation and following provisional stenting if necessary and were evaluated for baseline characteristics of plaque or in-stent restenosis (ISR), vessel wall trauma after angioplasty, presence of thrombus, stent apposition, and tissue prolapse. Imaging follow-up was not included in this study's protocol. Results: Twenty-seven obstructive lesions (18 cases of de novo atherosclerosis and 9 of ISR) of the femoropopliteal artery were imaged and 148 acquisitions were analyzed in total. High-resolution intravascular OCT imaging with effective blood clearance was achieved in 93.9%. Failure was mainly attributed to preocclusive proximal lesions and/or collateral flow. Mixed features of lipid pool areas, calcium deposits, necrotic core, and fibrosis were identified in all of the imaged atherosclerotic lesions, whereas ISR was purely fibrotic. After balloon angioplasty, OCT identified extensive intimal tears in all cases and one case of severe dissection that biplane subtraction angiography failed to identify. Conclusions: Infrainguinal frequency-domain optical coherence tomography is safe and feasible and may provide intravascular high-resolution imaging of the femoropopliteal artery during infrainguinal angioplasty procedures.

  20. An electro-responsive hydrogel for intravascular applications: an in vitro and in vivo evaluation.

    PubMed

    Verbrugghe, Peter; Verhoeven, Jelle; Coudyzer, Walter; Verbeken, Eric; Dubruel, Peter; Mendes, Eduardo; Stam, Frank; Meuris, Bart; Herijgers, Paul

    2015-11-01

    There is a growing interest in using hydrogels for biomedical applications, because of more favourable characteristics. Some of these hydrogels can be activated by using particular stimuli, for example electrical fields. These stimuli can change the hydrogel shape in a predefined way. It could make them capable of adaptation to patient-specific anatomy even post-implantation. This is the first paper aiming to describe in vivo studies of an electro-responsive, Pluronic F127 based hydrogel, for intravascular applications. Pluronic methacrylic acid hydrogel (PF127/MANa) was in vitro tested for its haemolytic and cytotoxic effects. Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation. Indirect and direct testing of the material gave no indication of the haemolytic effects of the material. Determination of fibroblast viability after 24 h of incubation in an extract of the hydrogel showed no cytotoxic effects. Occlusion was obtained within 1 h following in vivo implantation. Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall. An important proof-of-concept was obtained showing biocompatibility and effectiveness of a pluronic based electro-responsive hydrogel for obtaining an arterial occlusion with limited biological impact. So the selected pluronic-methacrylic acid based hydrogel can be used as an endovascular occlusion device. More importantly it is the first step in further development of electro-active hydrogels for a broad range of intra-vascular applications (e.g. system to prevent endoleakage in aortic aneurysm treatment, intra-vascular drug delivery).

  1. An electro-responsive hydrogel for intravascular applications: an in vitro and in vivo evaluation.

    PubMed

    Verbrugghe, Peter; Verhoeven, Jelle; Coudyzer, Walter; Verbeken, Eric; Dubruel, Peter; Mendes, Eduardo; Stam, Frank; Meuris, Bart; Herijgers, Paul

    2015-11-01

    There is a growing interest in using hydrogels for biomedical applications, because of more favourable characteristics. Some of these hydrogels can be activated by using particular stimuli, for example electrical fields. These stimuli can change the hydrogel shape in a predefined way. It could make them capable of adaptation to patient-specific anatomy even post-implantation. This is the first paper aiming to describe in vivo studies of an electro-responsive, Pluronic F127 based hydrogel, for intravascular applications. Pluronic methacrylic acid hydrogel (PF127/MANa) was in vitro tested for its haemolytic and cytotoxic effects. Minimal invasive implantation in the carotid artery of sheep was used to evaluate its medium-term biological effects, through biochemical, macroscopic, radiographic, and microscopic evaluation. Indirect and direct testing of the material gave no indication of the haemolytic effects of the material. Determination of fibroblast viability after 24 h of incubation in an extract of the hydrogel showed no cytotoxic effects. Occlusion was obtained within 1 h following in vivo implantation. Evaluation at time of autopsy showed a persistent occlusion with no systemic effects, no signs of embolization and mild effects on the arterial wall. An important proof-of-concept was obtained showing biocompatibility and effectiveness of a pluronic based electro-responsive hydrogel for obtaining an arterial occlusion with limited biological impact. So the selected pluronic-methacrylic acid based hydrogel can be used as an endovascular occlusion device. More importantly it is the first step in further development of electro-active hydrogels for a broad range of intra-vascular applications (e.g. system to prevent endoleakage in aortic aneurysm treatment, intra-vascular drug delivery). PMID:26474577

  2. Utilization of prostate brachytherapy for low risk prostate cancer: Is the decline overstated?

    PubMed Central

    Wong, Andrew; Weiner, Joseph P.; Schwartz, David; Schreiber, David

    2016-01-01

    Purpose Several prior studies have suggested that brachytherapy utilization has markedly decreased, coinciding with the recent increased utilization of intensity modulated radiation therapy, as well as an increase in urologist-owned centers. We sought to investigate the brachytherapy utilization in a large, hospital-based registry. Material and methods Men with prostate cancer diagnosed between 2004-2012 and treated with either external beam radiation and/or prostate brachytherapy were abstracted from the National Cancer Database. In order to be included, men had to be clinically staged as T1c-T2aNx-0Mx-0, Gleason 6, PSA ≤ 10.0 ng/ml. Descriptive statistics were used to analyze brachytherapy utilization over time and were compared via χ2. Multivariate logistic regression was used to assess for covariables associated with increased brachytherapy usage. Results There were 89,413 men included in this study, of which 37,054 (41.6%) received only external beam radiation, and 52,089 (58.4%) received prostate brachytherapy. The use of brachytherapy declined over time from 62.9% in 2004 to 51.3% in 2012 (p < 0.001). This decline was noted in both academic facilities (60.8% in 2004 to 47.0% in 2012, p < 0.001) as well as in non-academic facilities (63.7% in 2004 to 53.0% in 2012, p < 0.001). The decline was more pronounced in patients who lived closer to treatment facilities than those who lived further. The use of intensity modulated radiation therapy increased during this same time period from 18.4% in 2004 to 38.2% in 2012 (p < 0.001). On multivariate analysis, treatment at an academic center, increasing age, decreasing distance from the treatment center, and years of diagnosis from 2006-2012 were significantly associated with reduced brachytherapy usage. Conclusions In this hospital-based registry, prostate brachytherapy usage has declined for low risk prostate cancer as intensity modulated radiation therapy usage has increased. However, it still remains the

  3. Utilization of prostate brachytherapy for low risk prostate cancer: Is the decline overstated?

    PubMed Central

    Wong, Andrew; Weiner, Joseph P.; Schwartz, David; Schreiber, David

    2016-01-01

    Purpose Several prior studies have suggested that brachytherapy utilization has markedly decreased, coinciding with the recent increased utilization of intensity modulated radiation therapy, as well as an increase in urologist-owned centers. We sought to investigate the brachytherapy utilization in a large, hospital-based registry. Material and methods Men with prostate cancer diagnosed between 2004-2012 and treated with either external beam radiation and/or prostate brachytherapy were abstracted from the National Cancer Database. In order to be included, men had to be clinically staged as T1c-T2aNx-0Mx-0, Gleason 6, PSA ≤ 10.0 ng/ml. Descriptive statistics were used to analyze brachytherapy utilization over time and were compared via χ2. Multivariate logistic regression was used to assess for covariables associated with increased brachytherapy usage. Results There were 89,413 men included in this study, of which 37,054 (41.6%) received only external beam radiation, and 52,089 (58.4%) received prostate brachytherapy. The use of brachytherapy declined over time from 62.9% in 2004 to 51.3% in 2012 (p < 0.001). This decline was noted in both academic facilities (60.8% in 2004 to 47.0% in 2012, p < 0.001) as well as in non-academic facilities (63.7% in 2004 to 53.0% in 2012, p < 0.001). The decline was more pronounced in patients who lived closer to treatment facilities than those who lived further. The use of intensity modulated radiation therapy increased during this same time period from 18.4% in 2004 to 38.2% in 2012 (p < 0.001). On multivariate analysis, treatment at an academic center, increasing age, decreasing distance from the treatment center, and years of diagnosis from 2006-2012 were significantly associated with reduced brachytherapy usage. Conclusions In this hospital-based registry, prostate brachytherapy usage has declined for low risk prostate cancer as intensity modulated radiation therapy usage has increased. However, it still remains the

  4. Eptifibatide-induced thrombocytopenia: with thrombosis and disseminated intravascular coagulation immediately after left main coronary artery percutaneous coronary angioplasty.

    PubMed

    Tempelhof, Michael W; Benzuly, Keith H; Fintel, Dan; Krichavsky, Marc Z

    2012-01-01

    Early clinical trials of eptifibatide did not show a significant association between eptifibatide and the development of thrombocytopenia, thrombosis, or disseminated intravascular coagulation. However, more recent literature has suggested a significant association between eptifibatide and the development of thrombocytopenia and thrombosis. Although the true incidence and the pathophysiology of these associations are unknown, the development of these events can be life-threatening. Herein, we describe the case of a patient who experienced acute onset of profound thrombocytopenia, developing thrombosis, pulmonary emboli, and disseminated intravascular coagulation. This paper adds to the few previous reports of cases that suggested an association between thrombocytopenia, thrombosis, and the administration of eptifibatide. To the best of our knowledge, this is the first case report in the medical literature that associates the new onset of thrombocytopenia, thrombosis, and disseminated intravascular coagulation with the administration of eptifibatide. We also provide a subject review.

  5. Intravascular Papillary Endothelial Hyperplasia: Diagnostic Sequence and Literature Review of an Orofacial Lesion

    PubMed Central

    Guledgud, Mahima V.; Patil, Karthikeya; Saikrishna, Degala; Yelamali, Tejesh

    2014-01-01

    Intravascular papillary endothelial hyperplasia or Masson's tumor is a rare reactive disease of vascular origin characterized by exuberant proliferation of endothelial cells notably occurring within blood vessels of head, neck, and extremities. The importance of this entity is its ability to mimic a variety of diseases both benign and malignant in the orofacial region. Here, we present a case of Masson's tumor within the masseter muscle in a 40-year-old female with emphasis on the sequential investigative procedures performed to diagnose this entity. PMID:24891960

  6. Successful Intravascular Ultrasound-Guided Transradial Coronary Intervention with a 4Fr Guiding Catheter

    PubMed Central

    Sadamatsu, Kenji

    2016-01-01

    Minimizing the catheter size can reduce vascular access complications and contrast dye usage in coronary angiography. The small diameter of the 4Fr guiding catheter has limited the use of several angioplasty devices such as intravascular ultrasound (IVUS) in the past. However, the combination of a novel IVUS catheter and a 0.010 guidewire makes it possible to perform IVUS-guided percutaneous coronary intervention (PCI) with a 4Fr guiding catheter. We herein report the case of a 51-year-old man with silent myocardial ischemia who underwent IVUS-guided transradial PCI with a 4Fr guiding catheter. PMID:27672455

  7. Acute kidney injury and disseminated intravascular coagulation due to mercuric chloride poisoning

    PubMed Central

    Dhanapriya, J.; Gopalakrishnan, N.; Arun, V.; Dineshkumar, T.; Sakthirajan, R.; Balasubramaniyan, T.; Haris, M.

    2016-01-01

    Mercury is a toxic heavy metal and occurs in organic and inorganic forms. Inorganic mercury includes elemental mercury and mercury salts. Mercury salts are usually white powder or crystals, and widely used in indigenous medicines and folk remedies in Asia. Inorganic mercury poisoning causes acute kidney injury (AKI) and gastrointestinal manifestations and can be life-threatening. We describe a case with unknown substance poisoning who developed AKI and disseminated intravascular coagulation (DIC). Renal biopsy showed acute tubular necrosis. Later, the consumed substance was proven to be mercuric chloride. His renal failure improved over time, and his creatinine normalized after 2 months. PMID:27194836

  8. Intestinal Intravascular Large B-cell Lymphoma Mimicking Ulcerative Colitis with Secondary Membranoproliferative Glomerulonephritis.

    PubMed

    Kaneyuki, Daisuke; Komeno, Yukiko; Yoshimoto, Hiroshi; Yoshimura, Naoki; Iihara, Kuniko; Ryu, Tomiko

    2016-01-01

    A 47-year-old woman with ulcerative colitis (UC) was admitted to our hospital for renal dysfunction and progressive anemia. Colonoscopy revealed intestinal lesions and pathological findings showed intravascular large B-cell lymphoma (IVLBCL). According to the polymerase chain reaction analysis of sequential rectal specimens, we concluded that she suffered from intestinal BCL, not UC. After chemotherapy, her renal function progressed to nephrotic syndrome. The pathological findings of renal biopsy specimens indicated membranoproliferative glomerulonephritis (MPGN). Chemotherapy was continued and led to the remission of BCL and MPGN. We herein describe the first case of intestinal IVLBCL mimicking UC with secondary MPGN. PMID:27580553

  9. Intravascular low-level laser irradiation in the treatment of psoriasis

    NASA Astrophysics Data System (ADS)

    Zhu, Jing; Shi, Hong-Min; Zhang, Hui-Guo; Zhang, Mei-Jue; Xu, Jian; Zhou, Min; Hu, Guo-Qiang

    1998-11-01

    Liu TCY et al have put forward the biological information model on low intensity laser irradiation (BIML): low intensity laser irradiation couples with intracellular messenger through the chromophore absorption in the cell membrane: hot-color laser irradiation activates cAMP phosphodiestererase through Gi protein, or activates phosphoinositide phospholipase C through G protein, or activates one of receptor-associated kinases: cAMP; cold- color laser irradiation activates adenylate cyclase through Gs protein: cAMP$ARUP. In this paper, under the guidance of BIML, we applied the intravascular low intensity He-He laser irradiation on blood to a patient of idiopathic edema, and succeeded.

  10. Blue or red: which intravascular laser light has more effects in diabetic patients?

    PubMed

    KazemiKhoo, N; Ansari, F

    2015-01-01

    The effects of intravascular laser irradiation of blood (ILIB), with 405 and 632.8 nm on serum blood sugar (BS) level, were comparatively studied. Twenty-four diabetic type 2 patients received 14 sessions of ILIB with blue and red lights. BS was measured before and after therapy. Serum BS decreased highly significant after ILIB with both red and blue lights (p < 0.0001), but we did not find significant difference between red and blue lights. The ILIB effect would be of benefit in the clinical treatment of diabetic type 2 patients, irrespective of lasers (blue or red lights) that are used.

  11. Rash, disseminated intravascular coagulation and legionella: Episode 10 and a rewind into the past

    PubMed Central

    Thalanayar, Prashanth M.; Holguin, Fernando

    2015-01-01

    Legionella pneumophila is the most common cause of legionellosis and is one of the organisms causing atypical pneumonia. We report the presentation of disseminated intravascular coagulation (DIC) and skin rash in a single case of severe Legionella pneumonia. The unique clinical presentation of a diffuse rash diagnosed as purpura fulminans and the unpredictable variations encountered during the diagnostic work-up of the case make this write-up crucial. This article synthesizes all reported cases of L. pneumonia associated with cutaneous manifestations as well as cases presenting with DIC. Furthermore, this manuscript illustrates the correlation between cutaneous and coagulopathic manifestations, and morbidity and mortality from L. pneumonia. PMID:26236615

  12. Specific imaging of atherosclerotic plaque lipids with two-wavelength intravascular photoacoustics

    PubMed Central

    Wu, Min; Jansen, Krista; van der Steen, Antonius F. W.; van Soest, Gijs

    2015-01-01

    The lipid content in plaques is an important marker for identifying atherosclerotic lesions and disease states. Intravascular photoacoustic (IVPA) imaging can be used to visualize lipids in the artery. In this study, we further investigated lipid detection in the 1.7-µm spectral range. By exploiting the relative difference between the IVPA signal strengths at 1718 and 1734 nm, we could successfully detect and differentiate between the plaque lipids and peri-adventitial fat in human coronary arteries ex vivo. Our study demonstrates that IVPA imaging can positively identify atherosclerotic plaques using only two wavelengths, which could enable rapid data acquisition in vivo. PMID:26417500

  13. Successful Intravascular Ultrasound-Guided Transradial Coronary Intervention with a 4Fr Guiding Catheter.

    PubMed

    Nakano, Yasuhiro; Sadamatsu, Kenji

    2016-01-01

    Minimizing the catheter size can reduce vascular access complications and contrast dye usage in coronary angiography. The small diameter of the 4Fr guiding catheter has limited the use of several angioplasty devices such as intravascular ultrasound (IVUS) in the past. However, the combination of a novel IVUS catheter and a 0.010 guidewire makes it possible to perform IVUS-guided percutaneous coronary intervention (PCI) with a 4Fr guiding catheter. We herein report the case of a 51-year-old man with silent myocardial ischemia who underwent IVUS-guided transradial PCI with a 4Fr guiding catheter. PMID:27672455

  14. High-resolution coregistered intravascular imaging with integrated ultrasound and optical coherence tomography probe

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Yin, Jiechen; Hu, Changhong; Zhou, Qifa; Shung, K. Kirk; Chen, Zhongping

    2010-09-01

    We report an integrated ultrasound (US) and optical coherence tomography (OCT) probe and system for intravascular imaging. The dual-function probe is based on a 50 MHz focused ring US transducer, with a centric hole for mounting OCT probe. The coaxial US and light beams are steered by a 45° mirror to enable coregistered US/OCT imaging simultaneously. Lateral resolution of US is improved due to focused ultrasonic beam. Mirror effects on US were investigated and in vitro imaging of a rabbit aorta has been carried out. The combined US-OCT system demonstrated high resolution in visualizing superficial arterial structures while retaining deep penetration of ultrasonic imaging.

  15. Potential for tissue characterization of plaque and arterial wall using intravascular ultrasound

    NASA Astrophysics Data System (ADS)

    Sudhir, Krishnakutty; Fitzgerald, Peter J.; Yock, Paul G.

    1993-09-01

    Current intravascular ultrasound imaging technology is able to determine the extent and distribution of pathologic processes within the vessel wall, but is not highly sensitive in discriminating between different types of pathologic tissue. `Tissue characterization' refers to a set of computer-based techniques that utilize features of the ultrasound signal beyond basic amplitude to help define the structure of the tissue of interest. Although preliminary results with this approach are encouraging, additional work is needed to define its clinical application in vascular disease.

  16. Zero Contrast Coronary Intervention Using Intravascular Ultrasound Guidance in a Patient with Allergy to Contrast Medium.

    PubMed

    Nagaoka, Masakazu; Tsumuraya, Naoko; Nie, Masaki; Ikari, Yuji

    2016-01-01

    The occurrence of allergy to iodinated contrast in certain patients may prevent the use of percutaneous coronary intervention (PCI) in such cases. We present a 53-year-old male with a history of allergic reaction to iodinated contrast who successfully underwent intravascular ultrasound (IVUS) guided PCI. Stent size was determined based on IVUS. After PCI, stent expansion and a lack of edge dissection or incomplete apposition were confirmed by IVUS. Thus, PCI without contrast injection under IVUS may be feasible in selected patients with allergy to iodinated contrast. PMID:27628609

  17. Primary bilateral adrenal intravascular large B-cell lymphoma associated with adrenal failure.

    PubMed

    Fukushima, Ayumi; Okada, Yosuke; Tanikawa, Takahisa; Onaka, Takashi; Tanaka, Aya; Higashi, Takehiro; Tsukada, Junichi; Tanaka, Yoshiya

    2003-07-01

    We report a rare case of bilateral primary adrenal non-Hodgkin's lymphoma with adrenal failure. A 66-year-old woman developed symptoms of adrenal failure. The cause of adrenal failure was suspected to be malignant lymphoma based on the high levels of serum soluble interleukin-2 receptor and LDH. Bilateral adrenalectomy was performed and pathological examination showed intravascular large B-cell lymphoma (IVL). Although complete remission was achieved, recurrence occurred three months later with brain metastases. IVL should be suspected in patients with bilateral adrenal tumors who present with rapidly progressive adrenal failure.

  18. Successful Intravascular Ultrasound-Guided Transradial Coronary Intervention with a 4Fr Guiding Catheter

    PubMed Central

    Sadamatsu, Kenji

    2016-01-01

    Minimizing the catheter size can reduce vascular access complications and contrast dye usage in coronary angiography. The small diameter of the 4Fr guiding catheter has limited the use of several angioplasty devices such as intravascular ultrasound (IVUS) in the past. However, the combination of a novel IVUS catheter and a 0.010 guidewire makes it possible to perform IVUS-guided percutaneous coronary intervention (PCI) with a 4Fr guiding catheter. We herein report the case of a 51-year-old man with silent myocardial ischemia who underwent IVUS-guided transradial PCI with a 4Fr guiding catheter.

  19. Mechanical effects of muscle contraction increase intravascular ATP draining quiescent and active skeletal muscle in humans

    PubMed Central

    Crecelius, Anne R.; Kirby, Brett S.; Richards, Jennifer C.

    2013-01-01

    Intravascular adenosine triphosphate (ATP) evokes vasodilation and is implicated in the regulation of skeletal muscle blood flow during exercise. Mechanical stresses to erythrocytes and endothelial cells stimulate ATP release in vitro. How mechanical effects of muscle contractions contribute to increased plasma ATP during exercise is largely unexplored. We tested the hypothesis that simulated mechanical effects of muscle contractions increase [ATP]venous and ATP effluent in vivo, independent of changes in tissue metabolic demand, and further increase plasma ATP when superimposed with mild-intensity exercise. In young healthy adults, we measured forearm blood flow (FBF) (Doppler ultrasound) and plasma [ATP]v (luciferin-luciferase assay), then calculated forearm ATP effluent (FBF×[ATP]v) during rhythmic forearm compressions (RFC) via a blood pressure cuff at three graded pressures (50, 100, and 200 mmHg; Protocol 1; n = 10) and during RFC at 100 mmHg, 5% maximal voluntary contraction rhythmic handgrip exercise (RHG), and combined RFC + RHG (Protocol 2; n = 10). [ATP]v increased from rest with each cuff pressure (range 144–161 vs. 64 ± 13 nmol/l), and ATP effluent was graded with pressure. In Protocol 2, [ATP]v increased in each condition compared with rest (RFC: 123 ± 33; RHG: 51 ± 9; RFC + RHG: 96 ± 23 vs. Mean Rest: 42 ± 4 nmol/l; P < 0.05), and ATP effluent was greatest with RFC + RHG (RFC: 5.3 ± 1.4; RHG: 5.3 ± 1.1; RFC + RHG: 11.6 ± 2.7 vs. Mean Rest: 1.2 ± 0.1 nmol/min; P < 0.05). We conclude that the mechanical effects of muscle contraction can 1) independently elevate intravascular ATP draining quiescent skeletal muscle without changes in local metabolism and 2) further augment intravascular ATP during mild exercise associated with increases in metabolism and local deoxygenation; therefore, it is likely one stimulus for increasing intravascular ATP during exercise in humans. PMID:23429876

  20. Sudden death due to intravascular hemolysis after bladder irrigation with distilled water.

    PubMed

    Bell, M D

    1992-09-01

    A 45-year-old white man was hospitalized with gross hematuria, one month after cystoscopy and biopsy for the same complaint. The biopsy revealed cystitis glandularis. One day after admission, he developed seizures and died within hours. Autopsy, laboratory tests, and further questioning of the hospital staff showed that he died of acute hyponatremia and massive intravascular hemolysis after irrigating the bladder with sterile water. Two deep bladder ulcers with exposed veins served as the portals of entry. Until now, this fatal complication had been described only during transurethral surgery. Both a careful autopsy and hospital investigation is necessary to differentiate in-hospital natural death from iatrogenic fatality. PMID:1402764

  1. Surgical removal of an intravascular ultrasonography catheter captured in a stent after percutaneous coronary intervention.

    PubMed

    Minami, Hiroya; Asada, Tatsuro; Gan, Kunio; Yamada, Akitoshi; Sato, Masanobu

    2011-03-01

    A-79-year-old woman underwent percutaneous coronary intervention (PCI) to the right coronary artery (RCA) for effort angina, followed by intravascular ultrasonography (IVUS) to ascertain stent expansion. The IVUS catheter became entangled in the stent and could not be withdrawn from the outside. The patient was transferred to our hospital for its surgical removal. For the emergent surgery, we opened the stent region in the RCA and directly removed the IVUS catheter with the twisted stent. Additional coronary artery bypass grafting (CABG) involving three vessels was performed. She was discharged 42 days after surgery. PMID:21448795

  2. A Case of Cystic Adventitial Degeneration of the Left Popliteal Artery Diagnosed by Intravascular Ultrasound

    PubMed Central

    Niizeki, Takeshi; Ishino, Mitsunori; Kitahara, Tatsuro; Yamauchi, So; Ikeno, Eiichiro; Kubota, Isao

    2016-01-01

    An 87-year-old male was admitted with intermittent claudication of the left calf. We performed lower extremity angiography, which revealed stenosis of the left popliteal artery. Intravascular ultrasound (IVUS) image correctly identified the cystic appearance of visualized extravascular hypodensity, causing extrinsic compression of the lumen. We diagnosed the condition as cystic adventitial degeneration (CAD) of the popliteal artery. We operated a resection of a cyst with the artery and replaced the autovein graft (saphenous vein). After surgery, the patient was free of symptoms. CAD is a rare disease; thus, our IVUS findings may provide unique diagnostic clues in patients with CAD. PMID:26949345

  3. A comparison of the expected costs of high dose rate brachytherapy using 252Cf versus 192Ir.

    PubMed

    Rivard, Mark J; Kirk, Bernadette L; Stapleford, Liza J; Wazer, David E

    2004-12-01

    A cost analysis to compare high dose rate (HDR) brachytherapy using either californium-252 (252Cf) or 192Ir was performed to determine the prospects of widespread clinical implementation of HDR 252Cf. Interest in the neutron-emitting 252Cf radioisotope as a radiotherapy nuclide has undergone a resurgence given recent efforts to fabricate HDR remotely afterloaded sources, and other efforts to create a miniature source for improved accessibility to a variety of anatomic sites. Therefore, HDR 252Cf brachytherapy may prove to be a potential rival to the use of HDR 192Ir remotely afterloaded brachytherapy--the current standard-of-care treatment modality using HDR brachytherapy. Considering the possible improvements in clinical efficacy using HDR 252Cf brachytherapy and the enormous costs of other high-LET radiation sources, the cost differences between 252Cf and 192Ir may be well-justified.

  4. Brachytherapy in Greater Poland Cancer Centre and in Poznan – the past and the presence

    PubMed Central

    2009-01-01

    The aim of this article is to describe the history of brachytherapy in Poznań from the beginning of 20th century. Among the most important medical and oncological institutions that were created in Poznań at the beginning of twentieth century were: Surgical Clinic of Poznań University (City Hospital, Poznań), Transfiguration of the Lord Hospital (Poznań) and Radiology Faculty of Poznań University (Poznań). After the World War II in 1953 at Garbary Street hospital three new departments were established: Surgery, Gynecology and General Departments. At that time, radium treatment was introduced to Gynecology and General Departments and it was applied in therapy till the early nineties, in spite of introducing LDR and HDR brachytherapy in seventies and eighties. The intense development of brachytherapy took place in late nineties, when brachytherapy treatment of non-gynecological tumors started. Today’s condition of brachytherapy at Greater Poland Cancer Centre (GCC) is presented in this article, too.

  5. Tolerance of the carotid-sheath contents to brachytherapy: an experimental study

    SciTech Connect

    Werber, J.L.; Sood, B.; Alfieri, A.; McCormick, S.A.; Vikram, B. )

    1991-06-01

    Tumor invasion of the carotid artery is a potential indication for brachytherapy, which delivers a high dose of irradiation to residual tumor while limiting the dose to adjacent healthy tissues. The tolerance of carotid-sheath contents to varying doses of brachytherapy, however, has not been clearly established. In order to evaluate brachytherapy effects on carotid-sheath contents, after-loading catheters were implanted bilaterally in 3 groups of 6 rabbits each (18 rabbits). Iridium 192 brachytherapy doses of either 5000 cGy (rad), 9000 cGy, or 13,000 cGy were delivered unilaterally, with the contralateral neck serving as a nonirradiated control in each animal. There were no carotid ruptures and wound healing was normal. Two animals from each group were killed at 6, 20, and 48 weeks. Even at the highest dose (13,000 cGy), nerve conduction studies performed on the vagus nerve prior to sacrifice revealed no increased latency, histologic changes were minimal, and carotid arteries were patent. These observations suggest that the carotid-sheath contents in healthy rabbits could tolerate high doses (up to 13,000 cGy) of low-dose-rate interstitial brachytherapy without complications.

  6. Case Series of Pulmonary Tumor Embolism and Intravascular Lymphoma: Evaluation of the Usefulness of Pulmonary Microvascular Cytology.

    PubMed

    Ishiguro, Takashi; Takayanagi, Noboru; Baba, Yuri; Kagiyama, Naho; Miyamoto, Takashi; Mutoh, Makoto; Shimizu, Yoshihiko; Sugita, Yutaka

    2016-01-01

    Pulmonary tumor embolism (PTE) and intravascular lymphoma cause rapidly progressive deterioration and an antemortem diagnosis is difficult. The usefulness of pulmonary microvascular cytology (PMC) in the diagnosis of these disorders has been reported in sporadic case reports. We retrospectively evaluated the records of 7 patients with tumor cells in the pulmonary microvasculature (4 with PTE and 3 with malignant lymphoma) who underwent pulmonary microvascular cytology. Two of the 4 patients with PTE and 2 of the 3 patients with malignant lymphoma (all 3 had intravascular metastasis) had positive PMC results. These findings suggested that PMC may be useful in the diagnosis of these disorders. PMID:27629967

  7. Patient perception of local anesthesia for prostate brachytherapy.

    PubMed

    Smathers, S; Wallner, K; Simpson, C; Roof, J

    2000-05-01

    Prostate brachytherapy is an increasingly popular treatment for early-stage prostate cancer. Until now, spinal or general anesthesia for the procedure has been the standard of care. For patient safety, patient convenience, and to limit use of operating facilities, the authors started performing implants routinely with local anesthesia. We present here an evaluation of patients' acceptance of prostate brachytherapy under local anesthesia. On arrival at our department on the morning of the procedure, the patient is brought into the simulator suite, an intravenous line is started, and a urinary catheter is inserted. With the patient in the lithotomy position, a 5-by-5-cm patch of perineal skin and subcutaneous tissue is anesthetized by local infiltration of 10 mL of 1% lidocaine, using a 25-gauge 5/8-inch needle. Immediately following injection into the subcutaneous tissues, the deeper tissues, including the pelvic floor and prostate apex, are anesthetized by injecting 15 mL lidocaine solution with approximately 8 passes of a 20-gauge 1-inch needle. Following subcutaneous and periapical lidocaine injections, the transrectal ultrasound (TRUS) probe is positioned to reproduce the planning images and a 3.5- or 6-inch, 22-gauge spinal needle is inserted into the peripheral planned needle tracks, monitored by TRUS. When the tips of the needles reach the prostatic base, about 1 mL of lidocaine solution is injected in the intraprostatic track, as the needle is slowly withdrawn. The lidocaine infiltration procedure takes approximately 10 to 15 minutes. Seed implantation is then performed as previously described. At the time of this report preparation, 58 of the 71 patients (81%) were interviewed, with a median follow-up of 6 months since the implant procedure. On a scale of 1 to 10, the median biopsy pain score was 4.5 compared with a median pain score with the implant procedure of 3.0. There was no clear correlation between the two scores (r = .26). There was no correlation

  8. Error Analysis of non-TLD HDR Brachytherapy Dosimetric Techniques

    NASA Astrophysics Data System (ADS)

    Amoush, Ahmad

    The American Association of Physicists in Medicine Task Group Report43 (AAPM-TG43) and its updated version TG-43U1 rely on the LiF TLD detector to determine the experimental absolute dose rate for brachytherapy. The recommended uncertainty estimates associated with TLD experimental dosimetry include 5% for statistical errors (Type A) and 7% for systematic errors (Type B). TG-43U1 protocol does not include recommendation for other experimental dosimetric techniques to calculate the absolute dose for brachytherapy. This research used two independent experimental methods and Monte Carlo simulations to investigate and analyze uncertainties and errors associated with absolute dosimetry of HDR brachytherapy for a Tandem applicator. An A16 MicroChamber* and one dose MOSFET detectors† were selected to meet the TG-43U1 recommendations for experimental dosimetry. Statistical and systematic uncertainty analyses associated with each experimental technique were analyzed quantitatively using MCNPX 2.6‡ to evaluate source positional error, Tandem positional error, the source spectrum, phantom size effect, reproducibility, temperature and pressure effects, volume averaging, stem and wall effects, and Tandem effect. Absolute dose calculations for clinical use are based on Treatment Planning System (TPS) with no corrections for the above uncertainties. Absolute dose and uncertainties along the transverse plane were predicted for the A16 microchamber. The generated overall uncertainties are 22%, 17%, 15%, 15%, 16%, 17%, and 19% at 1cm, 2cm, 3cm, 4cm, and 5cm, respectively. Predicting the dose beyond 5cm is complicated due to low signal-to-noise ratio, cable effect, and stem effect for the A16 microchamber. Since dose beyond 5cm adds no clinical information, it has been ignored in this study. The absolute dose was predicted for the MOSFET detector from 1cm to 7cm along the transverse plane. The generated overall uncertainties are 23%, 11%, 8%, 7%, 7%, 9%, and 8% at 1cm, 2cm, 3cm

  9. Plaque Brachytherapy for Uveal Melanoma: A Vision Prognostication Model

    SciTech Connect

    Khan, Niloufer; Khan, Mohammad K.; Bena, James; Macklis, Roger; Singh, Arun D.

    2012-11-01

    Purpose: To generate a vision prognostication model after plaque brachytherapy for uveal melanoma. Methods and Materials: All patients with primary single ciliary body or choroidal melanoma treated with iodine-125 or ruthenium-106 plaque brachytherapy between January 1, 2005, and June 30, 2010, were included. The primary endpoint was loss of visual acuity. Only patients with initial visual acuity better than or equal to 20/50 were used to evaluate visual acuity worse than 20/50 at the end of the study, and only patients with initial visual acuity better than or equal to 20/200 were used to evaluate visual acuity worse than 20/200 at the end of the study. Factors analyzed were sex, age, cataracts, diabetes, tumor size (basal dimension and apical height), tumor location, and radiation dose to the tumor apex, fovea, and optic disc. Univariate and multivariable Cox proportional hazards were used to determine the influence of baseline patient factors on vision loss. Kaplan-Meier curves (log rank analysis) were used to estimate freedom from vision loss. Results: Of 189 patients, 92% (174) were alive as of February 1, 2011. At presentation, visual acuity was better than or equal to 20/50 and better than or equal to 20/200 in 108 and 173 patients, respectively. Of these patients, 44.4% (48) had post-treatment visual acuity of worse than 20/50 and 25.4% (44) had post-treatment visual acuity worse than 20/200. By multivariable analysis, increased age (hazard ratio [HR] of 1.01 [1.00-1.03], P=.05), increase in tumor height (HR of 1.35 [1.22-1.48], P<.001), and a greater total dose to the fovea (HR of 1.01 [1.00-1.01], P<.001) were predictive of vision loss. This information was used to develop a nomogram predictive of vision loss. Conclusions: By providing a means to predict vision loss at 3 years after treatment, our vision prognostication model can be an important tool for patient selection and treatment counseling.

  10. Water equivalent phantom materials for 192Ir brachytherapy

    NASA Astrophysics Data System (ADS)

    Schoenfeld, Andreas A.; Harder, Dietrich; Poppe, Björn; Chofor, Ndimofor

    2015-12-01

    Several solid phantom materials have been tested regarding their suitability as water substitutes for dosimetric measurements in brachytherapy with 192Ir as a typical high energy photon emitter. The radial variations of the spectral photon fluence, of the total, primary and scattered photon fluence and of the absorbed dose to water in the transversal plane of the tested cylindrical phantoms surrounding a centric and coaxially arranged Varian GammaMed afterloading 192Ir brachytherapy source were Monte-Carlo simulated in EGSnrc. The degree of water equivalence of a phantom material was evaluated by comparing the radial dose-to-water profile in the phantom material with that in water. The phantom size was varied over a large range since it influences the dose contribution by scattered photons with energies diminished by single and multiple Compton scattering. Phantom axis distances up to 10 cm were considered as clinically relevant. Scattered photons with energies reaching down into the 25 keV region dominate the photon fluence at source distances exceeding 3.5 cm. The tested phantom materials showed significant differences in the degree of water equivalence. In phantoms with radii up to 10 cm, RW1, RW3, Solid Water, HE Solid Water, Virtual Water, Plastic Water DT, and Plastic Water LR phantoms show excellent water equivalence with dose deviations from a water phantom not exceeding 0.8%, while Original Plastic Water (as of 2015), Plastic Water (1995), Blue Water, polyethylene, and polystyrene show deviations up to 2.6%. For larger phantom radii up to 30 cm, the deviations for RW1, RW3, Solid Water, HE Solid Water, Virtual Water, Plastic Water DT, and Plastic Water LR remain below 1.4%, while Original Plastic Water (as of 2015), Plastic Water (1995), Blue Water, polyethylene, and polystyrene produce deviations up to 8.1%. PMMA plays a separate role, with deviations up to 4.3% for radii not exceeding 10 cm, but below 1% for radii up to 30 cm. As suggested by

  11. Quantifying IOHDR brachytherapy underdosage resulting from an incomplete scatter environment

    SciTech Connect

    Raina, Sanjay; Avadhani, Jaiteerth S.; Oh, Moonseong; Malhotra, Harish K.; Jaggernauth, Wainwright; Kuettel, Michael R.; Podgorsak, Matthew B. . E-mail: matthew.podgorsak@roswellpark.org

    2005-04-01

    Purpose: Most brachytherapy planning systems are based on a dose calculation algorithm that assumes an infinite scatter environment surrounding the target volume and applicator. Dosimetric errors from this assumption are negligible. However, in intraoperative high-dose-rate brachytherapy (IOHDR) where treatment catheters are typically laid either directly on a tumor bed or within applicators that may have little or no scatter material above them, the lack of scatter from one side of the applicator can result in underdosage during treatment. This study was carried out to investigate the magnitude of this underdosage. Methods: IOHDR treatment geometries were simulated using a solid water phantom beneath an applicator with varying amounts of bolus material on the top and sides of the applicator to account for missing tissue. Treatment plans were developed for 3 different treatment surface areas (4 x 4, 7 x 7, 12 x 12 cm{sup 2}), each with prescription points located at 3 distances (0.5 cm, 1.0 cm, and 1.5 cm) from the source dwell positions. Ionization measurements were made with a liquid-filled ionization chamber linear array with a dedicated electrometer and data acquisition system. Results: Measurements showed that the magnitude of the underdosage varies from about 8% to 13% of the prescription dose as the prescription depth is increased from 0.5 cm to 1.5 cm. This treatment error was found to be independent of the irradiated area and strongly dependent on the prescription distance. Furthermore, for a given prescription depth, measurements in planes parallel to an applicator at distances up to 4.0 cm from the applicator plane showed that the dose delivery error is equal in magnitude throughout the target volume. Conclusion: This study demonstrates the magnitude of underdosage in IOHDR treatments delivered in a geometry that may not result in a full scatter environment around the applicator. This implies that the target volume and, specifically, the prescription

  12. Rapid emission angle selection for rotating-shield brachytherapy

    SciTech Connect

    Liu, Yunlong; Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Sun, Wenqing; Yang Wenjun; Wu Xiaodong

    2013-05-15

    Purpose: The authors present a rapid emission angle selection (REAS) method that enables the efficient selection of the azimuthal shield angle for rotating shield brachytherapy (RSBT). The REAS method produces a Pareto curve from which a potential RSBT user can select a treatment plan that balances the tradeoff between delivery time and tumor dose conformity. Methods: Two cervical cancer patients were considered as test cases for the REAS method. The RSBT source considered was a Xoft Axxent{sup TM} electronic brachytherapy source, partially shielded with 0.5 mm of tungsten, which traveled inside a tandem intrauterine applicator. Three anchor RSBT plans were generated for each case using dose-volume optimization, with azimuthal shield emission angles of 90 Degree-Sign , 180 Degree-Sign , and 270 Degree-Sign . The REAS method converts the anchor plans to treatment plans for all possible emission angles by combining neighboring beamlets to form beamlets for larger emission angles. Treatment plans based on exhaustive dose-volume optimization (ERVO) and exhaustive surface optimization (ERSO) were also generated for both cases. Uniform dwell-time scaling was applied to all plans such that that high-risk clinical target volume D{sub 90} was maximized without violating the D{sub 2cc} tolerances of the rectum, bladder, and sigmoid colon. Results: By choosing three azimuthal emission angles out of 32 potential angles, the REAS method performs about 10 times faster than the ERVO method. By setting D{sub 90} to 85-100 Gy{sub 10}, the delivery times used by REAS generated plans are 21.0% and 19.5% less than exhaustive surface optimized plans used by the two clinical cases. By setting the delivery time budget to 5-25 and 10-30 min/fx, respectively, for two the cases, the D{sub 90} contributions for REAS are improved by 5.8% and 5.1% compared to the ERSO plans. The ranges used in this comparison were selected in order to keep both D{sub 90} and the delivery time within acceptable

  13. Brachytherapy structural shielding calculations using Monte Carlo generated, monoenergetic data

    SciTech Connect

    Zourari, K.; Peppa, V.; Papagiannis, P.; Ballester, Facundo; Siebert, Frank-André

    2014-04-15

    Purpose: To provide a method for calculating the transmission of any broad photon beam with a known energy spectrum in the range of 20–1090 keV, through concrete and lead, based on the superposition of corresponding monoenergetic data obtained from Monte Carlo simulation. Methods: MCNP5 was used to calculate broad photon beam transmission data through varying thickness of lead and concrete, for monoenergetic point sources of energy in the range pertinent to brachytherapy (20–1090 keV, in 10 keV intervals). The three parameter empirical model introduced byArcher et al. [“Diagnostic x-ray shielding design based on an empirical model of photon attenuation,” Health Phys. 44, 507–517 (1983)] was used to describe the transmission curve for each of the 216 energy-material combinations. These three parameters, and hence the transmission curve, for any polyenergetic spectrum can then be obtained by superposition along the lines of Kharrati et al. [“Monte Carlo simulation of x-ray buildup factors of lead and its applications in shielding of diagnostic x-ray facilities,” Med. Phys. 34, 1398–1404 (2007)]. A simple program, incorporating a graphical user interface, was developed to facilitate the superposition of monoenergetic data, the graphical and tabular display of broad photon beam transmission curves, and the calculation of material thickness required for a given transmission from these curves. Results: Polyenergetic broad photon beam transmission curves of this work, calculated from the superposition of monoenergetic data, are compared to corresponding results in the literature. A good agreement is observed with results in the literature obtained from Monte Carlo simulations for the photon spectra emitted from bare point sources of various radionuclides. Differences are observed with corresponding results in the literature for x-ray spectra at various tube potentials, mainly due to the different broad beam conditions or x-ray spectra assumed. Conclusions

  14. AAPM Task Group 128: Quality assurance tests for prostate brachytherapy ultrasound systems

    SciTech Connect

    Pfeiffer, Douglas; Sutlief, Steven; Feng Wenzheng; Pierce, Heather M.; Kofler, Jim

    2008-12-15

    While ultrasound guided prostate brachytherapy has gained wide acceptance as a primary treatment tool for prostate cancer, quality assurance of the ultrasound guidance system has received very little attention. Task Group 128 of the American Association of Physicists in Medicine was created to address quality assurance requirements specific to transrectal ultrasound used for guidance of prostate brachytherapy. Accurate imaging guidance and dosimetry calculation depend upon the quality and accuracy of the ultrasound image. Therefore, a robust quality assurance program for the ultrasound system is essential. A brief review of prostate brachytherapy and ultrasound physics is provided, followed by a recommendation for elements to be included in a comprehensive test phantom. Specific test recommendations are presented, covering grayscale visibility, depth of penetration, axial and lateral resolution, distance measurement, area measurement, volume measurement, needle template/electronic grid alignment, and geometric consistency with the treatment planning computer.

  15. Simulation of dose distribution for iridium-192 brachytherapy source type-H01 using MCNPX

    NASA Astrophysics Data System (ADS)

    Purwaningsih, Anik

    2014-09-01

    Dosimetric data for a brachytherapy source should be known before it used for clinical treatment. Iridium-192 source type H01 was manufactured by PRR-BATAN aimed to brachytherapy is not yet known its dosimetric data. Radial dose function and anisotropic dose distribution are some primary keys in brachytherapy source. Dose distribution for Iridium-192 source type H01 was obtained from the dose calculation formalism recommended in the AAPM TG-43U1 report using MCNPX 2.6.0 Monte Carlo simulation code. To know the effect of cavity on Iridium-192 type H01 caused by manufacturing process, also calculated on Iridium-192 type H01 if without cavity. The result of calculation of radial dose function and anisotropic dose distribution for Iridium-192 source type H01 were compared with another model of Iridium-192 source.

  16. Simulation of dose distribution for iridium-192 brachytherapy source type-H01 using MCNPX

    SciTech Connect

    Purwaningsih, Anik

    2014-09-30

    Dosimetric data for a brachytherapy source should be known before it used for clinical treatment. Iridium-192 source type H01 was manufactured by PRR-BATAN aimed to brachytherapy is not yet known its dosimetric data. Radial dose function and anisotropic dose distribution are some primary keys in brachytherapy source. Dose distribution for Iridium-192 source type H01 was obtained from the dose calculation formalism recommended in the AAPM TG-43U1 report using MCNPX 2.6.0 Monte Carlo simulation code. To know the effect of cavity on Iridium-192 type H01 caused by manufacturing process, also calculated on Iridium-192 type H01 if without cavity. The result of calculation of radial dose function and anisotropic dose distribution for Iridium-192 source type H01 were compared with another model of Iridium-192 source.

  17. Rectal ulcer: Due to ketoprofen, argon plasma coagulation and prostatic brachytherapy.

    PubMed

    Koessler, Thibaud; Servois, Vincent; Mariani, Pascale; Aubert, Emilie; Cacheux, Wulfran

    2014-12-01

    Prostatic brachytherapy with permanent seed implants is a recent and safe radiation therapy technique associated with radiation-induced digestive disease. Argon plasma coagulation procedure is a validated modality in the management of haemorrhagic radiation proctitis, which is known to occasionally induce chronic rectal ulcers. We report here an original case report of an acute painful rectal ulcer as a consequence of the combination of short-term therapy with non-steroidal anti-inflammatory drugs therapy, prostatic brachytherapy with malposition of seed implants and argon plasma coagulation procedure in a patient with haemorrhagic radiation proctitis. The description of this clinical observation is essential to recommend the discontinuation of non-steroidal anti-inflammatory drugs therapy and the control of the position of seed implants in case of prostatic brachytherapy before argon plasma coagulation for radiation-induced proctitis.

  18. Magnetic resonance imaging-guided brachytherapy for cervical cancer: initiating a program

    PubMed Central

    Prisciandaro, Joann I.; Soliman, Abraam; Ravi, Ananth; Song, William Y.

    2015-01-01

    Over the past decade, the application of magnetic resonance imaging (MRI) has increased, and there is growing evidence to suggest that improvements in accuracy of target delineation in MRI-guided brachytherapy may improve clinical outcomes in cervical cancer. To implement a high quality image guided brachytherapy program, a multidisciplinary team is required with appropriate expertise as well as an adequate patient load to ensure a sustainable program. It is imperative to know that the most important source of uncertainty in the treatment process is related to target delineation and therefore, the necessity of training and expertise as well as quality assurance should be emphasized. A short review of concepts and techniques that have been developed for implementation and/or improvement of workflow of a MRI-guided brachytherapy program are provided in this document, so that institutions can use and optimize some of them based on their resources to minimize their procedure times. PMID:26622249

  19. Magnetic resonance imaging for planning intracavitary brachytherapy for the treatment of locally advanced cervical cancer.

    PubMed

    Oñate Miranda, M; Pinho, D F; Wardak, Z; Albuquerque, K; Pedrosa, I

    2016-01-01

    Cervical cancer is the third most common gynecological cancer. Its treatment depends on tumor staging at the time of diagnosis, and a combination of chemotherapy and radiotherapy is the treatment of choice in locally advanced cervical cancers. The combined use of external beam radiotherapy and brachytherapy increases survival in these patients. Brachytherapy enables a larger dose of radiation to be delivered to the tumor with less toxicity for neighboring tissues with less toxicity for neighboring tissues compared to the use of external beam radiotherapy alone. For years, brachytherapy was planned exclusively using computed tomography (CT). The recent incorporation of magnetic resonance imaging (MRI) provides essential information about the tumor and neighboring structures making possible to better define the target volumes. Nevertheless, MRI has limitations, some of which can be compensated for by fusing CT and MRI. Fusing the images from the two techniques ensures optimal planning by combining the advantages of each technique.

  20. Potential role of ultrasound imaging in interstitial image based cervical cancer brachytherapy

    PubMed Central

    2014-01-01

    In 2012, more than 500,000 cases of cervical cancer were diagnosed worldwide. Over three quarters of these cases occur in less developed countries [1]. Advancements in image-guided brachytherapy are resulting in improved outcomes and reduced morbidity for women with this disease, but its worldwide adoption is hampered by lack of accessibility to advanced imaging techniques. Ultrasound is emerging as a potential option for tumor visualization, brachytherapy catheter placement, and treatment planning. While additional work is needed, ultrasound can potentially serve as the sole imaging modality for catheter insertion and planning. This paper will review our current knowledge on the use of ultrasound in interstitial brachytherapy treatment for cervical cancer. PMID:25097565

  1. Disseminated Intravascular Coagulation as a Complication of Abdominal Aortic Aneurysm Repair

    PubMed Central

    Mulcare, Robert J.; Royster, Thomas S.; Weiss, Harvey J.; Phillips, Louise L.

    1974-01-01

    A retrospective review was done of all patients undergoing surgical repair of abdominal aortic aneurysm (AAA) on whom coagulation studies were obtained. Those patients with laboratory documented disseminated intravascular coagulation (DIC) were selected and their clinical records reviewed. This included 7 patients studied in the periods 1964–1965 and January 1971–July 1973. Of these 7 cases, 4 occurred in patients undergoing emergency operation for ruptured aneurysm and 3 were in elective cases. All 7 patients exhibited clinical evidence of abnormal bleeding, while 6 of the 7 progressed rapidly to renal shutdown. The seventh patient recovered spontaneously. Of the 6 patients with full blown clinical and laboratory evidence of DIC, 2 recovered. Both cases received heparin therapy and multiple hemodialyses. A third patient was started on heparin but died at 36 hours in heart failure. All 3 patients receiving heparin showed clinical cessation of abnormal bleeding and disappearance of soluble fibrin monomer complexes within 24 hours of starting therapy. The study suggests a higher incidence of DIC than has previously been appreciated in both the emergency and elective repair of AAA. The prompt recognition and treatment of this complication may reverse the abnormal intravascular clotting, minimize its more serious results and avoid futile and dangerous operative intervention. ImagesFig. 3. PMID:4851404

  2. [Optical coherence tomography of coronary arteries--a novel intravascular imaging modality].

    PubMed

    Mrevlje, B; Legutko, J; Jąkała, J; Noč, M; Dudek, D; Birkemeyer, R; Aboukoura, M; Nienaber, C

    2014-09-01

    Optical coherence tomography (OCT) is the latest intravascular imaging modality for the investigation of coronary arteries. It can be used in patients with stable coronary artery disease as well as in patients with acute coronary syndrome. Its almost microscope-like resolution of 10-20 μm (10-times greater than intravascular ultrasound) gives us the most detailed insight into the coronary artery wall in vivo so far.Optical coherence tomography can be used for accurate qualitative and quantitative assessment of stenoses in stable coronary artery disease and accurate guidance of percutaneous coronary interventions as well as accurate postprocedural control. In patients with acute coronary syndrome it can be used for the detection of culprit of the culprit lesion (vulnerable plaque) which allows the operator to cover not only angiographically tightest stenosis (angiographic culprit lesion, caused in most cases by thrombus only) but most importantly the vulnerable plaque, which led to the acute event, as well. Furthermore, optical coherence tomography allows accurate assessment of thrombotic burden, stent apposition/malapposition, edge dissections and tissue prolaps or thrombus protrusions throught stent struts, etc. PMID:25225864

  3. NIR fluorescence lifetime sensing through a multimode fiber for intravascular molecular probing

    NASA Astrophysics Data System (ADS)

    Ingelberts, H.; Hernot, S.; Debie, P.; Lahoutte, T.; Kuijk, M.

    2016-04-01

    Coronary artery disease (CAD) contributes to millions of deaths each year. The identification of vulnerable plaques is essential to the diagnosis of CAD but is challenging. Molecular probes can improve the detection of these plaques using intravascular imaging methods. Fluorescence lifetime sensing is a safe and robust method to image these molecular probes. We present two variations of an optical system for intravascular near-infrared (NIR) fluorescence lifetime sensing through a multimode fiber. Both systems are built around a recently developed fast and efficient CMOS detector, the current-assisted photonic sampler (CAPS) that is optimized for sub-nanosecond NIR fluorescence lifetime sensing. One system mimics the optical setup of an epifluorescence microscope while the other uses a practical fiber optic coupler to separate fluorescence excitation and emission. We test both systems by measuring the lifetime of several NIR dyes in DMSO solutions and we show that these systems are capable of detecting lifetimes of solutions with concentrations down to 370 nM and this with short acquisition times. These results are compared with time-correlated single photon counting (TCSPC) measurements for reference.

  4. Release of plasmid DNA from intravascular stents coated with ultrathin multilayered polyelectrolyte films.

    PubMed

    Jewell, Christopher M; Zhang, Jingtao; Fredin, Nathaniel J; Wolff, Matthew R; Hacker, Timothy A; Lynn, David M

    2006-09-01

    Materials that permit control over the release of DNA from the surfaces of topologically complex implantable devices, such as intravascular stents, could contribute to the development of new approaches to the localized delivery of DNA. We report the fabrication of ultrathin, multilayered polyelectrolyte films that permit both the immobilization and controlled release of plasmid DNA from the surfaces of stainless steel intravascular stents. Our approach makes use of an aqueous-based, layer-by-layer method for the assembly of nanostructured thin films consisting of alternating layers of plasmid DNA and a hydrolytically degradable polyamine. Characterization of coated stents using scanning electron microscopy (SEM) demonstrated that stents were coated uniformly with an ultrathin film ca. 120 nm thick that adhered conformally to the surfaces of stent struts. These ultrathin films did not crack, peel, or delaminate substantially from the surface after exposure to a range of mechanical challenges representative of those encountered during stent deployment (e.g., balloon expansion). Stents coated with eight bilayers of degradable polyamine and a plasmid encoding enhanced green fluorescent protein (EGFP) sustained the release of DNA into solution for up to four days when incubated in phosphate buffered saline at 37 degrees C, and coated stents were capable of mediating the expression of EGFP in a mammalian cell line without the aid of additional transfection agents. The approach reported here could, with further development, contribute to the development of localized gene-based approaches to the treatment of cardiovascular diseases or related conditions. PMID:16961308

  5. Atomic layer deposition enhanced grafting of phosphorylcholine on stainless steel for intravascular stents.

    PubMed

    Zhong, Qi; Yan, Jin; Qian, Xu; Zhang, Tao; Zhang, Zhuo; Li, Aidong

    2014-09-01

    In-stent restenosis (ISR) and re-endothelialization delay are two major issues of intravascular stent in terms of clinical safety and effects. Construction of mimetic cell membrane surface on stents using phosphorylcholine have been regarded as one of the most powerful strategies to resolve these two issues and improve the performance of stents. In this study, atomic layer deposition (ALD) technology, which is widely used in semiconductor industry, was utilized to fabricate ultra-thin layer (10nm) of alumina (Al2O3) on 316L stainless steel (SS), then the alumina covered surface was modified with 3-aminopropyltriethoxysilane (APS) and 2-methacryloyloxyethyl phosphorylcholine (MPC) sequentially in order to produce phosphorylcholine mimetic cell membrane surface. The pristine and modified surfaces were characterized using X-ray photoelectron spectroscopy, atomic force microscope and water contact angle measurement. Furthermore, the abilities of protein adsorption, platelet adhesion and cell proliferation on the surfaces were investigated. It was found that alumina layer can significantly enhance the surface grafting of APS and MPC on SS; and in turn efficiently inhibit protein adsorption and platelet adhesion, and promote the attachment and proliferation of human umbilical vein endothelial cells (HUVEC) on the surfaces. In association with the fact that the deposition of alumina layer is also beneficial to the improvement of adhesion and integrity of drug-carrying polymer coating on drug eluting stents, we expect that ALD technology can largely assist in the modifications on inert metallic surfaces and benefit implantable medical devices, especially intravascular stents.

  6. Computational analysis of the effectiveness of blood flushing with saline injection from an intravascular diagnostic catheter

    PubMed Central

    Ghata, Narugopal; Aldredge, Ralph C.; Bec, Julien; Marcu, Laura

    2015-01-01

    SUMMARY Optical techniques including fluorescence lifetime spectroscopy have demonstrated potential as a tool for study and diagnosis of arterial vessel pathologies. However, their application in the intravascular diagnostic procedures has been hampered by the presence of blood hemoglobin that affects the light delivery to and the collection from the vessel wall. We report a computational fluid dynamics model that allows for the optimization of blood flushing parameters in a manner that minimizes the amount of saline needed to clear the optical field of view and reduces any adverse effects caused by the external saline jet. A 3D turbulence (k−ω) model was employed for Eulerian–Eulerian two-phase flow to simulate the flow inside and around a side-viewing fiber-optic catheter. Current analysis demonstrates the effects of various parameters including infusion and blood flow rates, vessel diameters, and pulsatile nature of blood flow on the flow structure around the catheter tip. The results from this study can be utilized in determining the optimal flushing rate for given vessel diameter, blood flow rate, and maximum wall shear stress that the vessel wall can sustain and subsequently in optimizing the design parameters of optical-based intravascular catheters. PMID:24953876

  7. Disposal of plasma heme in normal man and patients with intravascular hemolysis

    PubMed Central

    Sears, David A.

    1970-01-01

    The clearance of plasma protein-bound heme, its sites of removal, and the reutilization of hemeiron were studied by radioisotopic techniques in normal human subjects and in patients with intravascular hemolysis. In normal subjects, injected heme-59Fe was bound immediately by albumin and the β1-globulin, hemopexin. Its clearance from the plasma was descr bed by a single exponential equation, and the half-life in plasma was 7-8 hr. Removal was largely by the liver. Iron reutilization began promptly, and half the injected heme-iron was incorporated into circulating red cells within one cell life-span. In patients with intravascular hemolysis, hemopexin was depleted, and injected heme was bound solely to albumin. Plasma clearance was described by a double exponential equation of the form: y = Ae-k1t + Be-k2t. The half-lives of the two components averaged 3.9 and 22.2 hr, respectively. Removal was by the liver in at least some of the patients, and iron reutilization was variable, depending on the state of body iron stores. When hemopex'n was depleted in a normal subject by repeated heme injection, clearance mimicked that observed in the patients. Images PMID:4188269

  8. Disposal of plasma heme in normal man and patients with intravascular hemolysis.

    PubMed

    Sears, D A

    1970-01-01

    The clearance of plasma protein-bound heme, its sites of removal, and the reutilization of hemeiron were studied by radioisotopic techniques in normal human subjects and in patients with intravascular hemolysis. In normal subjects, injected heme-(59)Fe was bound immediately by albumin and the beta(1)-globulin, hemopexin. Its clearance from the plasma was descr bed by a single exponential equation, and the half-life in plasma was 7-8 hr. Removal was largely by the liver. Iron reutilization began promptly, and half the injected heme-iron was incorporated into circulating red cells within one cell life-span. In patients with intravascular hemolysis, hemopexin was depleted, and injected heme was bound solely to albumin. Plasma clearance was described by a double exponential equation of the form: y = Ae(-k1t) + Be(-k2t). The half-lives of the two components averaged 3.9 and 22.2 hr, respectively. Removal was by the liver in at least some of the patients, and iron reutilization was variable, depending on the state of body iron stores. When hemopex'n was depleted in a normal subject by repeated heme injection, clearance mimicked that observed in the patients.

  9. Elimination of Bloodstream Infections Associated with Candida albicans Biofilm in Intravascular Catheters

    PubMed Central

    Akbari, Freshta; Kjellerup, Birthe Veno

    2015-01-01

    Intravascular catheters are among the most commonly inserted medical devices and they are known to cause a large number of catheter related bloodstream infections (BSIs). Biofilms are associated with many chronic infections due to the aggregation of microorganisms. One of these organisms is the fungus Candida albicans. It has shown to be one of the leading causes of catheter-related BSIs. The presence of biofilm on intravascular catheters provide increased tolerance against antimicrobial treatments, thus alternative treatment strategies are sought. Traditionally, many strategies, such as application of combined antimicrobials, addition of antifungals, and removal of catheters, have been practiced, but they were not successful in eradicating BSIs. Since these fungal infections can result in significant morbidity, mortality, and increased healthcare cost, other promising preventive strategies, including antimicrobial lock therapy, chelating agents, alcohol, and biofilm disruptors, have been applied. In this review, current success and failure of these new approaches, and a comparison with the previous strategies are discussed in order to understand which preventative treatment is the most effective in controlling the catheter-related BSIs. PMID:26131615

  10. Lipid detection by intravascular photoacoustic imaging with flexible catheter at 20 fps (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Wu, Min; Daeichin, Verya; Springeling, Geert; van der Steen, Antonius F. W.; van Soest, Gijs

    2016-02-01

    Intravascular Photoacoustic (IVPA) imaging is a promising new technology to assess lipid content of coronary atherosclerotic plaque, an important determinant of the risk associated with the plaque triggering a heart attack. Clinical translation of IVPA imaging requires real-time image acquisition, which has been a technological challenge. In this work, we demonstrate a high-speed, dual-wavelength IVPA imaging system at 1.7 µm wavelength, operating with a flexible catheter of 1.2 mm outer diameter (including outer sheath). The catheter was custom designed and fabricated, and used a 40 MHz transducer for intravascular ultrasound (IVUS) and IVPA imaging. The optical excitation is provided by a dual OPO system, pumped by CW diode-pumped Q-switched Nd:YAG lasers, with a repetition rate of 5 kHz. Each OPO can be tuned to a custom wavelength between 1690 and 1750 nm; two wavelengths only are needed to discriminate between plaque lipids and adipose tissue. The pulse energy is about 80 µJ. We tested the imaging performance of the presented system in a polyvinyl-alcohol (PVA) vessel mimicking phantom and human coronary arteries ex vivo. IVPA identified lipid deposits inside atherosclerotic plaque, while IVUS showed tissue structure. We demonstrated IVPA imaging at a speed of 20 frames per second, with 250 A-scans per frame. This is significantly faster than previous IVPA imaging systems, and will enable the translation of IVPA imaging into clinical practice.

  11. Design factors of intravascular dual frequency transducers for super-harmonic contrast imaging and acoustic angiography

    NASA Astrophysics Data System (ADS)

    Ma, Jianguo; Martin, K. Heath; Li, Yang; Dayton, Paul A.; Shung, K. Kirk; Zhou, Qifa; Jiang, Xiaoning

    2015-05-01

    Imaging of coronary vasa vasorum may lead to assessment of the vulnerable plaque development in diagnosis of atherosclerosis diseases. Dual frequency transducers capable of detection of microbubble super-harmonics have shown promise as a new contrast-enhanced intravascular ultrasound (CE-IVUS) platform with the capability of vasa vasorum imaging. Contrast-to-tissue ratio (CTR) in CE-IVUS imaging can be closely associated with low frequency transmitter performance. In this paper, transducer designs encompassing different transducer layouts, transmitting frequencies, and transducer materials are compared for optimization of imaging performance. In the layout selection, the stacked configuration showed superior super-harmonic imaging compared with the interleaved configuration. In the transmitter frequency selection, a decrease in frequency from 6.5 MHz to 5 MHz resulted in an increase of CTR from 15 dB to 22 dB when receiving frequency was kept constant at 30 MHz. In the material selection, the dual frequency transducer with the lead magnesium niobate-lead titanate (PMN-PT) 1-3 composite transmitter yielded higher axial resolution compared to single crystal transmitters (70 μm compared to 150 μm pulse length). These comparisons provide guidelines for the design of intravascular acoustic angiography transducers.

  12. Influence of distance and incident angle on light intensities in intravascular optical coherence tomography pullback runs

    NASA Astrophysics Data System (ADS)

    Liu, Shengnan; Eggermont, Jeroen; Wolterbeek, Ron; Lelieveldy, Boudewijn P. F.; Dijkstra, Jouke

    2016-02-01

    Intravascular optical coherence tomography (IVOCT) is an intravascular imaging modality which enables the visualization arterial structures at the micro-structural level. The interpretations of these structures is mainly on the basis of relative image intensities. However, even for homogeneous tissue light intensities can differ. In this study the incident light intensity is modeled to be related to the catheter position. Two factors, the distance between catheter and inner lumen wall as well as the incident angle of the light upon the lumen wall, are considered. A three-level hierarchical model is constructed to statistically validate this model to include the potential effect of different pullbacks and/or frame numbers. The model is solved using 169 images out of 9 pull-backs recorded with a St.Jude Medical IVOCT system. F-tests results indicate that both the distance and the incident angle contribute to the model statistically significantly with p < 0.001. Based on the results from the statistical analysis, a potential compensation method is introduced to normalize the IVOCT intensities for the catheter position effects and small shadows.

  13. Automatic classification of atherosclerotic plaques imaged with intravascular OCT (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Rico-Jimenez, Jose D.; Campos-Delgado, Daniel U.; Villiger, Martin; Bouma, Brett; Jo, Javier A.

    2016-03-01

    A novel computational method for plaque tissue characterization based on Intravascular Optical Coherence Tomography (IV-OCT) is presented. IV-OCT is becoming a powerful tool for the clinical evaluation of atherosclerotic plaques; however, it requires a trained expert for visual assessment and interpretation of the imaged plaques. Moreover, due to the inherit effect of speckle and the scattering attenuation of the optical scheme the direct interpretation of OCT images is limited. To overcome these difficulties, we propose to automatically identify the A-line profiles of the most significant plaque types (normal, fibrotic, or lipid-rich) and their respective abundance by using a probabilistic framework and blind alternated least squares to achieve the optimal decomposition. In this context, we present preliminary results of this novel probabilistic classification tool for intravascular OCT that relies on two steps. First, the B-scan is pre-processed to remove catheter artifacts, segment the lumen, select the region of interest (ROI), flatten the tissue surface, and reduce the speckle effect by a spatial entropy filter. Next, the resulting image is decomposed and its A-lines are classified by an automated strategy based on alternating-least-squares optimization. Our early results are encouraging and suggest that the proposed methodology can identify normal tissue, fibrotic and lipid-rich plaques from IV-OCT images.

  14. Fluorescence Lifetime Imaging and Intravascular Ultrasound: Co-Registration Study Using Ex Vivo Human Coronaries

    PubMed Central

    Gorpas, Dimitris; Fatakdawala, Hussain; Bec, Julien; Ma, Dinglong; Yankelevich, Diego R.; Qi, Jinyi

    2015-01-01

    Fluorescence lifetime imaging (FLIM) has demonstrated potential for robust assessment of atherosclerotic plaques biochemical composition and for complementing conventional intravascular ultrasound (IVUS), which provides information on plaque morphology. The success of such a bi-modal imaging modality depends on accurate segmentation of the IVUS images and proper angular registration between these two modalities. This paper reports a novel IVUS segmentation methodology addressing this issue. The image preprocessing consisted of denoising, using the Wiener filter, followed by image smoothing, implemented through the application of the alternating sequential filter on the edge separability metric images. Extraction of the lumen/intima and media/adventitia boundaries was achieved by tracing the gray-scale peaks over the A-lines of the IVUS preprocessed images. Cubic spline interpolation, in both cross-sectional and longitudinal directions, ensured boundary smoothness and continuity. The detection of the guide-wire artifact in both modalities is used for angular registration. Intraluminal studies were conducted in 13 ex vivo segments of human coronaries. The IVUS segmentation accuracy was assessed against independent manual tracings, providing 91.82% sensitivity and 97.55% specificity. The proposed methodology makes the bi-modal FLIM and IVUS approach feasible for comprehensive intravascular diagnosis by providing co-registered biochemical and morphological information of atherosclerotic plaques. PMID:25163056

  15. Intravascular photoacoustic imaging of atherosclerotic plaques: ex-vivo study using a rabbit model of atherosclerosis

    NASA Astrophysics Data System (ADS)

    Sethuraman, S.; Mallidi, S.; Aglyamov, S. R.; Amirian, J. H.; Litovsky, S.; Smalling, R. W.; Emelianov, S. Y.

    2007-02-01

    Diagnosis and treatment of atherosclerosis necessitates the detection and differentiation of rupture prone plaques. In principle, intravascular photoacoustic (IVPA) imaging has the ability to simultaneously visualize the structure and composition of atherosclerotic plaques by utilizing the difference in optical absorption. Extensive studies are required to validate the utility of IVPA imaging in detecting vulnerable plaques and address issues associated with the clinical implementation of the technique. In this work, we performed ex vivo imaging studies using a rabbit model of atherosclerosis. The intravascular photoacoustic (IVPA) and ultrasound (IVUS) images of the normal aorta and aorta with plaque were obtained and compared with histological slices of the tissue. The results indicate that IVPA imaging is capable of detecting plaques and showed potential in determining the composition. Furthermore, we initially addressed several aspects of clinical implementation of the IVPA imaging. Specifically, the configuration of combined IVPA and IVUS catheter was investigated and the effect of the optical absorption of the luminal blood on the IVPA image quality was evaluated. Overall, this study suggests that IVPA imaging can become a unique and important clinical tool.

  16. Pulmonary intravascular lymphoma detected by FDG PET-CT: a case report.

    PubMed

    Kohan, A A; Paganini, L; Biedak, P; Arma, J I; Dalurzo, M C L; Garcia-Monaco, R D

    2013-01-01

    Intravascular lymphoma is a rare subtype of extranodal Non-Hodgkin's lymphoma. Its prognosis is poor in a high percentage of cases due to its insidious appearance and low clinical suspicion. Its diagnosis is usually only reached after an autopsy. It may affect different organs as a whole or only one organ. It is extremely rare that the lung is the only damaged organ. Its diagnosis depends of the clinician's suspicion and proper evaluation with imaging studies as well as correct selection of the organ to be biopsied. When detected on time, the treatment of choice is a combination of a series of chemotherapy associated to a monoclonal antibody (anti-CD20). We present the case of a male patient who underwent a positron emission tomography-computed tomography with 2-[F-18]-fluoro-2 deoxy-D-glucose (FDG) due to symptoms suggestive of a lymphoproliferative disease with no clear structural abnormalities. The images led to a diagnosis of pulmonary intravascular large B cell lymphoma.

  17. Atomic layer deposition enhanced grafting of phosphorylcholine on stainless steel for intravascular stents.

    PubMed

    Zhong, Qi; Yan, Jin; Qian, Xu; Zhang, Tao; Zhang, Zhuo; Li, Aidong

    2014-09-01

    In-stent restenosis (ISR) and re-endothelialization delay are two major issues of intravascular stent in terms of clinical safety and effects. Construction of mimetic cell membrane surface on stents using phosphorylcholine have been regarded as one of the most powerful strategies to resolve these two issues and improve the performance of stents. In this study, atomic layer deposition (ALD) technology, which is widely used in semiconductor industry, was utilized to fabricate ultra-thin layer (10nm) of alumina (Al2O3) on 316L stainless steel (SS), then the alumina covered surface was modified with 3-aminopropyltriethoxysilane (APS) and 2-methacryloyloxyethyl phosphorylcholine (MPC) sequentially in order to produce phosphorylcholine mimetic cell membrane surface. The pristine and modified surfaces were characterized using X-ray photoelectron spectroscopy, atomic force microscope and water contact angle measurement. Furthermore, the abilities of protein adsorption, platelet adhesion and cell proliferation on the surfaces were investigated. It was found that alumina layer can significantly enhance the surface grafting of APS and MPC on SS; and in turn efficiently inhibit protein adsorption and platelet adhesion, and promote the attachment and proliferation of human umbilical vein endothelial cells (HUVEC) on the surfaces. In association with the fact that the deposition of alumina layer is also beneficial to the improvement of adhesion and integrity of drug-carrying polymer coating on drug eluting stents, we expect that ALD technology can largely assist in the modifications on inert metallic surfaces and benefit implantable medical devices, especially intravascular stents. PMID:25016426

  18. A Broadband Polyvinylidene Difluoride-Based Hydrophone with Integrated Readout Circuit for Intravascular Photoacoustic Imaging.

    PubMed

    Daeichin, Verya; Chen, Chao; Ding, Qing; Wu, Min; Beurskens, Robert; Springeling, Geert; Noothout, Emile; Verweij, Martin D; van Dongen, Koen W A; Bosch, Johan G; van der Steen, Antonius F W; de Jong, Nico; Pertijs, Michiel; van Soest, Gijs

    2016-05-01

    Intravascular photoacoustic (IVPA) imaging can visualize the coronary atherosclerotic plaque composition on the basis of the optical absorption contrast. Most of the photoacoustic (PA) energy of human coronary plaque lipids was found to lie in the frequency band between 2 and 15 MHz requiring a very broadband transducer, especially if a combination with intravascular ultrasound is desired. We have developed a broadband polyvinylidene difluoride (PVDF) transducer (0.6 × 0.6 mm, 52 μm thick) with integrated electronics to match the low capacitance of such a small polyvinylidene difluoride element (<5 pF/mm(2)) with the high capacitive load of the long cable (∼100 pF/m). The new readout circuit provides an output voltage with a sensitivity of about 3.8 μV/Pa at 2.25 MHz. Its response is flat within 10 dB in the range 2 to 15 MHz. The root mean square (rms) output noise level is 259 μV over the entire bandwidth (1-20 MHz), resulting in a minimum detectable pressure of 30 Pa at 2.25 MHz.

  19. Design factors of intravascular dual frequency transducers for super-harmonic contrast imaging and acoustic angiography

    PubMed Central

    Ma, Jianguo; Martin, K. Heath; Li, Yang; Dayton, Paul A.; Shung, K. Kirk; Zhou, Qifa; Jiang, Xiaoning

    2015-01-01

    Imaging of coronary vasa vasorum may lead to assessment of the vulnerable plaque development in diagnosis of atherosclerosis diseases. Dual frequency transducers capable of detection of microbubble super-harmonics have shown promise as a new contrast-enhanced intravascular ultrasound (CE-IVUS) platform with the capability of vasa vasorum imaging. Contrast-to-tissue ratio (CTR) in CE-IVUS imaging can be closely associated with the low frequency transmitter performance. In this paper, transducer designs encompassing different transducer layouts, transmitting frequencies, and transducer materials are compared for optimization of imaging performance. In the layout selection, the stacked configuration showed superior super-harmonic imaging compared with the interleaved configuration. In the transmitter frequency selection, a decrease in frequency from 6.5 MHz to 5 MHz resulted in an increase of CTR from 15 dB to 22 dB when receiving frequency was kept constant at 30 MHz. In the material selection, the dual frequency transducer with the lead magnesium niobate-lead titanate (PMN-PT) 1-3 composite transmitter yielded higher axial resolution compared to single crystal transmitters (70 μm compared to 150 μm pulse length). These comparisons provide guidelines for design of intravascular acoustic angiography transducers. PMID:25856384

  20. CONTRAST-ENHANCED INTRAVASCULAR ULTRASOUND PULSE SEQUENCES FOR BANDWIDTH-LIMITED TRANSDUCERS

    PubMed Central

    Maresca, David; Renaud, Guillaume; van Soest, Gijs; Li, Xiang; Zhou, Qifa; Shung, K. Kirk; de Jong, Nico; van der Steen, Antonius F. W.

    2013-01-01

    We demonstrate two methods for vasa vasorum imaging using contrast-enhanced intravascular ultrasound, which can be performed using commercial catheters. Plaque neovascularization was recognized as an independent marker of coronary artery plaque vulnerability. IVUS-based methods to image the microvessels available to date require high bandwidth (−6 dB relative frequency bandwidth >70%), which are not routinely available commercially. We explored the potential of ultraharmonic imaging and chirp reversal imaging for vasa vasorum imaging. In vitro recordings were performed on a tissue-mimicking phantom using a commercial ultrasound contrast agent and a transducer with a center frequency of 34 MHz and a −6 dB relative bandwidth of 56%. Acoustic peak pressures <500 kPa were used. A tissue-mimicking phantom with channels down to 200 μm in diameter was successfully imaged by the two contrast detection sequences while the smallest channel stayed invisible in conventional intravascular ultrasound images. Ultraharmonic imaging provided the best contrast agent detection. PMID:23384459

  1. Design factors of intravascular dual frequency transducers for super-harmonic contrast imaging and acoustic angiography.

    PubMed

    Ma, Jianguo; Martin, K Heath; Li, Yang; Dayton, Paul A; Shung, K Kirk; Zhou, Qifa; Jiang, Xiaoning

    2015-05-01

    Imaging of coronary vasa vasorum may lead to assessment of the vulnerable plaque development in diagnosis of atherosclerosis diseases. Dual frequency transducers capable of detection of microbubble super-harmonics have shown promise as a new contrast-enhanced intravascular ultrasound (CE-IVUS) platform with the capability of vasa vasorum imaging. Contrast-to-tissue ratio (CTR) in CE-IVUS imaging can be closely associated with low frequency transmitter performance. In this paper, transducer designs encompassing different transducer layouts, transmitting frequencies, and transducer materials are compared for optimization of imaging performance. In the layout selection, the stacked configuration showed superior super-harmonic imaging compared with the interleaved configuration. In the transmitter frequency selection, a decrease in frequency from 6.5 MHz to 5 MHz resulted in an increase of CTR from 15 dB to 22 dB when receiving frequency was kept constant at 30 MHz. In the material selection, the dual frequency transducer with the lead magnesium niobate-lead titanate (PMN-PT) 1-3 composite transmitter yielded higher axial resolution compared to single crystal transmitters (70 μm compared to 150 μm pulse length). These comparisons provide guidelines for the design of intravascular acoustic angiography transducers. PMID:25856384

  2. Evaluation of catheter-manometer systems for adequate intravascular blood pressure measurements in small animals.

    PubMed

    Idvall, J; Aronsen, K F; Lindström, K; Ulmsten, U

    1977-09-30

    Various catheter-manometer systems possible for intravascular blood pressure measurments on rats have been elaborated and tested in vitro and in vivo. Using a pressure-step calibrator, it was observed from in vitro studies that microtransducers had superior frequency response compared to conventional transducers. Of the catheters tested, Pe-90 tapered to a 40 mm tip with an inner diameter of 0.3 mm had the best frequency response as judged from fall and settling times. Because of the damping effect, tapering increased fall time to 1.8 ms, which was still quite acceptable. By the same token settling time was minimized to 22.4 ms. With a special calculation method the theoretical percentile fault of the recordings was estimated to be 9.66%. When the measurement error was calculated from the actual in vivo recordings, it was found to be no more than 2.7%. These results show that the technique described is adequate for continuous intravascular blood pressure recordings on small animals. Finally it is emphasized that careful handling of the catheters and avoidance of stopcocks and air bubbles are essential for obtaining accurate and reproducible values. PMID:928971

  3. Intravascular Ultrasound Catheter to Enhance Microbubble-Based Drug Delivery via Acoustic Radiation Force

    PubMed Central

    Kilroy, Joseph P.; Klibanov, Alexander L.; Wamhoff, Brian R.; Hossack, John A.

    2015-01-01

    Previous research has demonstrated that acoustic radiation force enhances intravascular microbubble adhesion to blood vessels in the presence of flow for molecular-targeted ultrasound imaging and drug delivery. A prototype acoustic radiation force intravascular ultrasound (ARFIVUS) catheter was designed and fabricated to displace a microbubble contrast agent in flow representative of conditions encountered in the human carotid artery. The prototype ARFIVUS transducer was designed to match the resonance frequency of 1.4- to 2.6-μm-diameter microbubbles modeled by an experimentally verified 1-D microbubble acoustic radiation force translation model. The transducer element was an elongated Navy Type I (hard) lead zirconate titanate (PZT) ceramic designed to operate at 3 MHz. Fabricated devices operated with center frequencies of 3.3 and 3.6 MHz with −6-dB fractional bandwidths of 55% and 50%, respectively. Microbubble translation velocities as high as 0.86 m/s were measured using a high-speed streak camera when insonating with the ARFIVUS transducer. Finally, the prototype was used to displace microbubbles in a flow phantom while imaging with a commercial 45-MHz imaging IVUS transducer. A sustained increase of 31 dB in average video intensity was measured following insonation with the ARFIVUS, indicating microbubble accumulation resulting from the application of acoustic radiation force. PMID:23143566

  4. A Broadband Polyvinylidene Difluoride-Based Hydrophone with Integrated Readout Circuit for Intravascular Photoacoustic Imaging.

    PubMed

    Daeichin, Verya; Chen, Chao; Ding, Qing; Wu, Min; Beurskens, Robert; Springeling, Geert; Noothout, Emile; Verweij, Martin D; van Dongen, Koen W A; Bosch, Johan G; van der Steen, Antonius F W; de Jong, Nico; Pertijs, Michiel; van Soest, Gijs

    2016-05-01

    Intravascular photoacoustic (IVPA) imaging can visualize the coronary atherosclerotic plaque composition on the basis of the optical absorption contrast. Most of the photoacoustic (PA) energy of human coronary plaque lipids was found to lie in the frequency band between 2 and 15 MHz requiring a very broadband transducer, especially if a combination with intravascular ultrasound is desired. We have developed a broadband polyvinylidene difluoride (PVDF) transducer (0.6 × 0.6 mm, 52 μm thick) with integrated electronics to match the low capacitance of such a small polyvinylidene difluoride element (<5 pF/mm(2)) with the high capacitive load of the long cable (∼100 pF/m). The new readout circuit provides an output voltage with a sensitivity of about 3.8 μV/Pa at 2.25 MHz. Its response is flat within 10 dB in the range 2 to 15 MHz. The root mean square (rms) output noise level is 259 μV over the entire bandwidth (1-20 MHz), resulting in a minimum detectable pressure of 30 Pa at 2.25 MHz. PMID:26856788

  5. Brachytherapy for early oral tongue cancer: low dose rate to high dose rate.

    PubMed

    Yamazaki, Hideya; Inoue, Takehiro; Yoshida, Ken; Yoshioka, Yasuo; Furukawa, Souhei; Kakimoto, Naoya; Shimizutani, Kimishige; Inoue, Toshihiko

    2003-03-01

    To examine the compatibility of low dose rate (LDR) with high dose rate (HDR) brachytherapy, we reviewed 399 patients with early oral tongue cancer (T1-2N0M0) treated solely by brachytherapy at Osaka University Hospital between 1967 and 1999. For patients in the LDR group (n = 341), the treatment sources consisted of Ir-192 pin for 227 patients (1973-1996; irradiated dose, 61-85 Gy; median, 70 Gy), Ra-226 needle for 113 patients (1967-1986; 55-93 Gy; median, 70 Gy). Ra-226 and Ir-192 were combined for one patient. Ir-192 HDR (microSelectron-HDR) was used for 58 patients in the HDR group (1991-present; 48-60 Gy; median, 60 Gy). LDR implantations were performed via oral and HDR via a submental/submandibular approach. The dose rates at the reference point for the LDR group were 0.30 to 0.8 Gy/h, and for the HDR group 1.0 to 3.4 Gy/min. The patients in the HDR group received a total dose of 48-60 Gy (8-10 fractions) during one week. Two fractions were administered per day (at least a 6-h interval). The 3- and 5-year local control rates for patients in the LDR group were 85% and 80%, respectively, and those in the HDR group were both 84%. HDR brachytherapy showed the same lymph-node control rate as did LDR brachytherapy (67% at 5 years). HDR brachytherapy achieved the same locoregional result as did LDR brachytherapy. A converting factor of 0.86 is applicable for HDR in the treatment of early oral tongue cancer.

  6. Brachytherapy in the therapy of prostate cancer – an interesting choice

    PubMed Central

    2013-01-01

    Brachytherapy is a curative alternative to radical prostatectomy or external beam radiation [i.e. 3D conformal external beam radiation therapy (CRT), intensity-modulated radiation therapy (IMRT)] with comparable long-term survival and biochemical control and the most favorable toxicity. HDR brachytherapy (HDR-BT) in treatment of prostate cancer is most frequently used together with external beam radiation therapy (EBRT) as a boost (increasing the treatment dose precisely to the tumor). In the early stages of the disease (low, sometimes intermediate risk group), HDR-BT is more often used as monotherapy. There are no significant differences in treatment results (overall survival rate – OS, local recurrence rate – LC) between radical prostatectomy, EBRT and HDR-BT. Low-dose-rate brachytherapy (LDR-BT) is a radiation method that has been known for several years in treatment of localized prostate cancer. The LDR-BT is applied as a monotherapy and also used along with EBRT as a boost. It is used as a sole radical treatment modality, but not as a palliative treatment. The use of brachytherapy as monotherapy in treatment of prostate cancer enables many patients to keep their sexual functions in order and causes a lower rate of urinary incontinence. Due to progress in medical and technical knowledge in brachytherapy (“real-time” computer planning systems, new radioisotopes and remote afterloading systems), it has been possible to make treatment time significantly shorter in comparison with other methods. This also enables better protection of healthy organs in the pelvis. The aim of this publication is to describe both brachytherapy methods. PMID:24596528

  7. Permanent prostate brachytherapy extracapsular radiation dose distributions: analysis of a multi-institutional database

    PubMed Central

    Butler, Wayne M.; Grimm, Peter; Morris, Mallory; Lief, Jonathan H.; Bennett, Abbey; Fiano, Ryan

    2013-01-01

    Purpose Periprostatic brachytherapy doses impact biochemical control. In this study, we evaluate extracapsular volumetric dosimetry following permanent prostate brachytherapy in patients entered in a multi-institutional community database. Material and methods In the database, 4547 patients underwent brachytherapy (3094 – 125I, 1437 – 103Pd and 16 – 131Cs). Using the originally determined prostate volume, a 5 mm, 3-dimensional peri-prostatic anulus was constructed around the prostate (except for a 2 mm posterior margin), and evaluated in its entirety and in 90° segments. Prostate dosimetric parameters consisted of a V100 and D90 while the annular dosimetry was reported as a V100. Results The intraprostatic V100 and D90 for 103Pd, and 125I were statistically comparable when stratified by isotope and/or monotherapy vs. boost. The overall mean V100 for the periprostatic annulus was 62.8%. The mean V100 at the base (51.6%) was substantially less than the apex (73.5%) and midgland (65.9%). In addition, for all patients, the anterior V100 (45.7%) was less than the lateral (68.8%) and the posterior (75.0%). The geometric V100 annular differences were consistent when evaluated by isotope. Overall, the V100 was higher in the 125I cohort. Conclusions The optimal extracapsular brachytherapy dose and radial extent remains unknown, but will prove increasingly important with reductions and/or elimination of supplemental external beam radiation therapy. The large multi-institutional community database demonstrates periprostatic annular doses that are not as robust as those in selected high volume brachytherapy centers, and may be inadequate for optimal biochemical control following monotherapeutic brachytherapy, especially in higher risk patients. PMID:24143144

  8. Verification of computerized treatment planning for HDR 192Ir brachytherapy for gynaecological cancer.

    PubMed

    Buzdar, Saeed Ahmad; Gadhi, Muhammad Asghar; Rao, Muhammad Afzal; Laghari, Naeem Ahmad; Anees, Mohammad

    2009-02-01

    Treatment planning in both teletherapy and brachytherapy is time consuming practice but accurate determination of planning parameters is more important. This paper aims to verify the dose delivery time for the treatment of vaginal cancer, which is a vital parameter of High Dose Rate (HDR) brachytherapy treatment planning. Treatment time has been calculated by the computerized treatment planning system (ABACUS 3.1), and then it has been compared with the manually calculated time. The results obtained are in good agreement. Independent verification of nominal time by two different protocols assures the quality of treatment. This should always be practiced to increase the accuracy of treatment.

  9. Magnetic resonance spectroscopy-guided transperineal prostate biopsy and brachytherapy for recurrent prostate cancer.

    PubMed

    Barnes, Agnieszka Szot; Haker, Steven J; Mulkern, Robert V; So, Minna; D'Amico, Anthony V; Tempany, Clare M

    2005-12-01

    Brachytherapy targeted to the peripheral zone with magnetic resonance imaging (MRI) guidance is a prostate cancer treatment option with potentially fewer complications than other treatments. Follow-up MRI when failure is suspected is, however, difficult because of radiation-induced changes. Furthermore, MR spectroscopy (MRS) is compromised by susceptibility artifacts from radioactive seeds in the peripheral zone. We report a case in which combined MRI/MRS was useful for the detection of prostate cancer in the transitional zone in patients previously treated with MR-guided brachytherapy. We propose that MRI/MRS can help detect recurrent prostate cancer, guide prostate biopsy, and help manage salvage treatment decisions. PMID:16360468

  10. Dose rate in brachytherapy using after-loading machine: pulsed or high-dose rate?

    PubMed

    Hannoun-Lévi, J-M; Peiffert, D

    2014-10-01

    Since February 2014, it is no longer possible to use low-dose rate 192 iridium wires due to the end of industrial production of IRF1 and IRF2 sources. The Brachytherapy Group of the French society of radiation oncology (GC-SFRO) has recommended switching from iridium wires to after-loading machines. Two types of after-loading machines are currently available, based on the dose rate used: pulsed-dose rate or high-dose rate. In this article, we propose a comparative analysis between pulsed-dose rate and high-dose rate brachytherapy, based on biological, technological, organizational and financial considerations.

  11. Salvage high-dose-rate (HDR) brachytherapy for recurrent head-and-neck cancer

    SciTech Connect

    Hepel, Jaroslaw T.; Syed, A.M. Nisar . E-mail: bvigil@memnet.org; Puthawala, Ajmel; Sharma, Anil; Frankel, Paul

    2005-08-01

    Background: A significant portion of head-and-neck cancer patients will develop persistent or recurrent disease after definitive treatment. Radiation therapy is often used as definitive therapy or as an adjunct to surgery. Recurrent cancer of the head and neck in the previously irradiated field is, thus, a common occurrence and poses a therapeutic challenge. Some studies have evaluated low-dose-rate (LDR) brachytherapy as a therapeutic option, including a large case series with long-term follow-up by our own institution. High-dose-rate (HDR) brachytherapy offers therapeutic advantages over LDR brachytherapy. This study evaluates the local control and outcomes of patients with previously irradiated recurrent head-and-neck cancer treated with HDR interstitial brachytherapy. Methods and Materials: Between 1997 and 2002, 30 patients who received prior radiation therapy for primary tumors of the head and neck were treated for biopsy-proven recurrent disease. All patients received previous radiation as definitive therapy alone or as adjunct to surgery. All patients were inoperable, refused surgery, or had gross residual disease after salvage surgery for their recurrent disease. Thirty-six sites on the 30 patients were implanted by application of high-dose-rate interstitial brachytherapy techniques with mean tumor dose of 34 Gy (18-48 Gy) in twice daily fractions of 300 to 400cGy per fraction. Results: At a minimum follow-up of 12 months, local tumor control was achieved in 69% of implanted sites. Disease-specific survival at 1 and 2 years was 54% and 45%, respectively. Overall survival at 1 and 2 years was 56% and 37%, respectively. Grade 3/4 late complications occurred in 16% of the patients. No fatal complications occurred. Conclusion: HDR brachytherapy can play an important role in the salvage treatment of previously irradiated recurrent head-and-neck cancer. This study shows that comparable results are obtained by HDR brachytherapy with fewer late complications than

  12. In vivo dosimetry: trends and prospects for brachytherapy

    PubMed Central

    Rosenfeld, A; Beddar, S; Tanderup, K; Cygler, J E

    2014-01-01

    The error types during brachytherapy (BT) treatments and their occurrence rates are not well known. The limited knowledge is partly attributed to the lack of independent verification systems of the treatment progression in the clinical workflow routine. Within the field of in vivo dosimetry (IVD), it is established that real-time IVD can provide efficient error detection and treatment verification. However, it is also recognized that widespread implementations are hampered by the lack of available high-accuracy IVD systems that are straightforward for the clinical staff to use. This article highlights the capabilities of the state-of-the-art IVD technology in the context of error detection and quality assurance (QA) and discusses related prospects of the latest developments within the field. The article emphasizes the main challenges responsible for the limited practice of IVD and provides descriptions on how they can be overcome. Finally, the article suggests a framework for collaborations between BT clinics that implemented IVD on a routine basis and postulates that such collaborations could improve BT QA measures and the knowledge about BT error types and their occurrence rates. PMID:25007037

  13. Surface optimization technique for MammoSite breast brachytherapy applicator

    SciTech Connect

    Kirk, Michael . E-mail: Michael_C_Kirk@rush.edu; Hsi, W.C.; Dickler, Adam; Chu, James; Dowlatshahi, Kambiz; Francescatti, Darius; Nguyen, Cam

    2005-06-01

    Purpose: We present a technique to optimize the dwell times and positions of a high-dose-rate {sup 192}Ir source using the MammoSite breast brachytherapy applicator. The surface optimization method used multiple dwell positions and optimization points to conform the 100% isodose line to the surface of the planning target volume (PTV). Methods and materials: The study population consisted of 20 patients treated using the MammoSite device between October 2002 and February 2004. Treatment was delivered in 10 fractions of 3.4 Gy/fraction, twice daily, with a minimum of 6 h between fractions. The treatment of each patient was planned using three optimization techniques. The dosimetric characteristics of the single-point, six-point, and surface optimization techniques were compared. Results: The surface optimization technique increased the PTV coverage compared with the single- and six-point methods (mean percentage of PTV receiving 100% of the prescription dose was 94%, 85%, and 91%, respectively). The surface method, single-point, and six-point method had a mean dose homogeneity index of 0.62, 0.68, and 0.63 and a mean full width at half maximum value of 189, 190, and 192 cGy/fraction, respectively. Conclusion: The surface technique provided greater coverage of the PTV than did the single- and six-point methods. Using the FWHM method, the surface, single-, and six-point techniques resulted in equivalent dose homogeneity.

  14. Successful percutaneous transluminal angioplasty and stenting for symptomatic intracranial vertebral artery stenosis using intravascular ultrasound virtual histology.

    PubMed

    Takayama, Katsutoshi; Taoka, Toshiaki; Nakagawa, Hiroyuki; Myouchin, Kaoru; Wada, Takeshi; Sakamoto, Masahiko; Fukusumi, Akio; Iwasaki, Satoru; Kurokawa, Shinichiro; Kichikawa, Kimihiko

    2007-06-01

    This is the first report of percutaneous transluminal angioplasty (PTA) of an intracranial artery applying intravascular ultrasound virtual histology (IVUS-VH), which has been recently developed for tissue characterization of coronary artery plaque. We report a case of successful PTA and stenting for symptomatic intracranial vertebral artery stenosis using IVUS-VH.

  15. The removal of intravascular bullets by interventional radiology: the prevention of central migration by balloon occlusion--case report.

    PubMed

    Sclafani, S J; Shatzkes, D; Scalea, T

    1991-10-01

    A migratory intravascular bullet fragment located within the hypogastric vein was removed successfully with the aid of interventional radiologic techniques. The authors describe the use of the technique of balloon trapping as part of this procedure. A balloon should be inflated between the foreign body and the heart before retrieval is attempted in order to prevent migration back to the heart during the manipulation.

  16. Intravascular Biphasic Synovial Sarcoma: The Beneficial Role of Adjuvant Treatment Approach in the Pre-metastatic Stage.

    PubMed

    Chicas-Sett, Rodolfo; Farga-Albiol, Dolores; Collado, Erica; Pacheco, Ariel; Zac, Carlos; Diaz, Roberto; Celada, Francisco; Burgos, Javier; Perez, Maria Jose; Tormo, Alejandro

    2016-04-16

    Synovial sarcoma (SS) is a high-grade, rare variant of soft tissue sarcoma (STS). The biphasic subtype is less common than the monophasic subtype. SS is very common around joint cavities in the extremities, but can be present elsewhere in the body. Tumor staging and therapeutic management are usually clear for a localized disease, but the proper management at the metastatic stage can be unclear. According to the literature, the histologic presence of an SS tumor thrombus affects tumor staging, making it unclear whether the tumor stage corresponds to localized or metastatic disease. An intravascular SS tumor exhibiting high metastatic potential is a rare finding that warrants thorough investigation. A 49-year-old woman presented with a biphasic SS intravascular tumor of the left inguinal area with femoral vessels involvement. Ten cases of intravascular SS have been reported in the literature and contain little information regarding the proper management of a local metastatic disease. Ours is a rare case of SS with an intravascular tumor occupying the femoral-iliac vein (as seen in metastatic disease) that has been treated as a local disease with a multidisciplinary therapeutic approach. As a result, our patient has been disease-free for two years and, during that time, has achieved an acceptable quality of life. We discuss the pertinent clinical findings of this rare tumor and review the literature of tumor thrombus by SS. We also present the multidisciplinary therapeutic approach realized and the history of this disease.

  17. Intravascular Biphasic Synovial Sarcoma: The Beneficial Role of Adjuvant Treatment Approach in the Pre-metastatic Stage

    PubMed Central

    Farga-Albiol, Dolores; Collado, Erica; Pacheco, Ariel; Zac, Carlos; Diaz, Roberto; Celada, Francisco; Burgos, Javier; Perez, Maria Jose; Tormo, Alejandro

    2016-01-01

    Synovial sarcoma (SS) is a high-grade, rare variant of soft tissue sarcoma (STS). The biphasic subtype is less common than the monophasic subtype. SS is very common around joint cavities in the extremities, but can be present elsewhere in the body. Tumor staging and therapeutic management are usually clear for a localized disease, but the proper management at the metastatic stage can be unclear. According to the literature, the histologic presence of an SS tumor thrombus affects tumor staging, making it unclear whether the tumor stage corresponds to localized or metastatic disease. An intravascular SS tumor exhibiting high metastatic potential is a rare finding that warrants thorough investigation. A 49-year-old woman presented with a biphasic SS intravascular tumor of the left inguinal area with femoral vessels involvement. Ten cases of intravascular SS have been reported in the literature and contain little information regarding the proper management of a local metastatic disease. Ours is a rare case of SS with an intravascular tumor occupying the femoral-iliac vein (as seen in metastatic disease) that has been treated as a local disease with a multidisciplinary therapeutic approach. As a result, our patient has been disease-free for two years and, during that time, has achieved an acceptable quality of life. We discuss the pertinent clinical findings of this rare tumor and review the literature of tumor thrombus by SS. We also present the multidisciplinary therapeutic approach realized and the history of this disease. PMID:27190730

  18. A Case of De Novo CD5+ Disseminated Intravascular Large B-Cell Lymphoma Presenting as Multiorgan Failure

    PubMed Central

    Kapuria, Devika; Nanua, Suparna; Gaur, Rakesh

    2016-01-01

    Intravascular large B-cell lymphoma is an extremely rare extranodal lymphoma that proliferates in the lumen of the blood vessels while sparing the organ parenchyma. It usually presents with CNS and skin involvement. A 65-year-old Caucasian female presented with fevers and chills of 3-4 months' duration. Bone marrow biopsy done 3 months prior showed no significant myelodysplasia or lymphoid aggregates. The patient later died due to multiorgan failure. A bone marrow biopsy showed 20–30% CD5+ B cells consistent with infiltrative large B-cell lymphoma. An autopsy performed revealed diffuse intravascular invasion by lymphoma cells. Multiorgan involvement by intravascular B-cell lymphoma is very rare. Based on our literature review and to the best of our knowledge, there are only 5 case reports describing the presentation of this lymphoma with multiorgan failure. The immunophenotypic studies performed revealed that our patient had de novo CD5+ intravascular large B-cell lymphoma which is known to be aggressive with very poor prognosis. Although it is an extremely rare lymphoma, it should be considered as a potential cause of multiorgan failure when no other cause has been identified. A prompt tissue diagnosis and high-dose chemotherapy followed by ASCT can sometimes achieve remission. PMID:27777803

  19. Intravascular Imaging

    NASA Astrophysics Data System (ADS)

    de Jong, Nico; Bom, Nicolaas; Schaar, Johannes; Goertz, David; Frijlink, Martijn; Steen, Anton Fw Van Der

    IVUS is used for diagnostics, therapy guidance and scientific purposes. It is the only clinical available technique that can assess plaque burden and free lumen diameter at high accuracy. Contrast angiography, which was the golden standard before IVUS, can only give a shadow projection of the lumen. Especially with the advent of 3D IVUS using pull backs it became an important tool for monitoring treatment and follow up of interventions like balloon angioplasty and placing of stents (wire prostheses that are used to prevent the arterial wall from recoiling). 3D IVUS in combination with biplane angiography allows assessment of true 3D reconstructions of arteries, pre and post treatment. Using computational fluid dynamics the velocity profile and thus the shear stress at the vascular wall can be calculated. This can be related to biological markers, which gives insight in formation of atherosclerosis, restenosis and remodelling.

  20. Intravascular Ultrasound

    MedlinePlus

    ... and a procedure called cardiac catheterization . IVUS uses sound waves to produce an image of the coronary arteries and to see their condition. The sound waves travel through a tube called a catheter. The ...

  1. Comparison of intravascular optical frequency domain imaging versus intravascular ultrasound during balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension

    PubMed Central

    Kubota, Shuji; Okazaki, Toru; Hara, Hisao; Hiroi, Yukio

    2016-01-01

    Objectives The aims of this study are (1) to evaluate the safety and feasibility of using optical frequency domain imaging (OFDI) during balloon pulmonary angioplasty (BPA) procedures, (2) to assess the correlations between the vessel area (VA) and luminal area (LA) obtained by OFDI and intravascular ultrasound (IVUS), and (3) to compare inter‐ and intra‐observer variability among measurements taken from OFDI and IVUS images. Background The BPA in patients with chronic thromboembolic pulmonary hypertension (CTEPH) is an evolving procedure. Methods Twenty‐three consecutive attempts of pair of OFDI and IVUS during BPA were evaluated. All complications that occurred during‐BPA and up to 48 hr post‐BPA were recorded. Using side branches as landmarks, 48 pairs of regions were chosen to compare measurements of VA and LA. Results OFDI images can be obtained without any procedurally related complications. Although the VA and LA measurements obtained by OFDI were smaller than those obtained by IVUS, high correlations were found (VA: r = 0.78, P < 0.0001 and LA: r = 0.75, P < 0.0001). Less inter‐ and intra‐observer variability was found when using measurements taken from OFDI versus IVUS images. Conclusions OFDI during BPA was safe and feasible. The reproducibility of OFDI imaging was excellent and offered a favorable addition to the BPA procedures. © 2016 The Authors Catheterization and Cardiovascular Interventions Published by Wiley Periodicals, Inc. PMID:26991798

  2. [The correlation between measurements performed by intravascular echography and quantitative digital angiography in large- and small-caliber arteries].

    PubMed

    Zamorano, J; Macaya, C; Alfonso, F; Goicolea, J; Iñíguez, A; Hernández-Antolín, R A; Ge, J; Zarco, P; Erbel, R; Meyer, J

    1992-04-01

    Intravascular ultrasound is a new promising technique that appears as a very useful complement to standard angiography in the study of atherosclerosis. Specifically, intravascular ultrasound provides by itself, information of great value concerning vessel wall characteristics. Nevertheless, before taking any decision with the results provided by this new technique, we must validate this information with that provided by other more conventional techniques like standard angiography. Accordingly, we have analyzed in 25 patients, 50 images of the abdominal aorta and 77 images of the coronary arteries taken from arterial segments free of atherosclerotic involvement. With the use of a calibrated small grid located over the patient's thorax, we have analyzed "in the same points" the images obtained with intravascular ultrasound and those provided by contrast angiography using a quantitative angiographic analysis. In the abdominal aorta the vessel diameter measured by intravascular ultrasound and angiography was 17.8 +/- 0.39 mm vs 18.6 +/- 0.42 mm (NS), whereas in the coronary arteries it was 2.76 +/- 0.39 mm vs 2.98 +/- 0.37 mm (NS), respectively. The correlation between both techniques was good for both types of arteries (r = 0.93 in the abdominal aorta and r = 0.87 in the coronary arteries). We conclude, that in our experience and with the methodology used, there is a good correlation between the measurements of the vessel diameters obtained by both intravascular ultrasound and digital angiography in arteries of different sizes, being the correlation even better in large arteries.

  3. Recommendations for Radioembolization of Hepatic Malignancies Using Yttrium-90 Microsphere Brachytherapy: A Consensus Panel Report from the Radioembolization Brachytherapy Oncology Consortium

    SciTech Connect

    Kennedy, Andrew; Nag, Subir . E-mail: subir.nag@kp.org; Salem, Riad; Murthy, Ravi; McEwan, Alexander J.; Nutting, Charles; Benson, Al; Espat, Joseph; Bilbao, Jose Ignacio; Sharma, Ricky A.; Thomas, James P.; Coldwell, Douglas

    2007-05-01

    Purpose: To standardize the indications, techniques, multimodality treatment approaches, and dosimetry to be used for yttrium-90 (Y90) microsphere hepatic brachytherapy. Methods and Materials: Members of the Radioembolization Brachytherapy Oncology Consortium met as an independent group of experts in interventional radiology, radiation oncology, nuclear medicine, medical oncology, and surgical oncology to identify areas of consensus and controversy and to issue clinical guidelines for Y90 microsphere brachytherapy. Results: A total of 14 recommendations are made with category 2A consensus. Key findings include the following. Sufficient evidence exists to support the safety and effectiveness of Y90 microsphere therapy. A meticulous angiographic technique is required to prevent complications. Resin microsphere prescribed activity is best estimated by the body surface area method. By virtue of their training, certification, and contribution to Y90 microsphere treatment programs, the disciplines of radiation oncology, nuclear medicine, and interventional radiology are all qualified to use Y90 microspheres. The panel strongly advocates the creation of a treatment registry with uniform reporting criteria. Initiation of clinical trials is essential to further define the safety and role of Y90 microspheres in the context of currently available therapies. Conclusions: Yttrium-90 microsphere therapy is a complex procedure that requires multidisciplinary management for safety and success. Practitioners and cooperative groups are encouraged to use these guidelines to formulate their treatment and dose-reporting policies.

  4. {beta}-Ray brachytherapy with {sup 106}Ru plaques for retinoblastoma

    SciTech Connect

    Schueler, Andreas O. . E-mail: andreas.schueler@uni-essen.de; Fluehs, Dirk; Anastassiou, Gerassimos; Jurklies, Christine; Neuhaeuser, Markus; Schilling, Harald; Bornfeld, Norbert; Sauerwein, Wolfgang

    2006-07-15

    Purpose: A retrospective analysis of 134 patients who received {sup 106}Ru brachytherapy for retinoblastomas (175 tumors in 140 eyes). Treatment and follow-up were analyzed with special emphasis on tumor control organ, preservation, and late complications. Results: Treated tumors had a mean height and diameter of 3.7 {+-} 1.4 mm and 5.0 {+-} 2.8 disk diameters, respectively. The radiation dose values were recalculated according to the calibration standard recently introduced by the National Institute of Standards and Technology. The recalculation revealed a mean applied dose of 419 Gy at the sclera (SD, 207 Gy) and 138 Gy (SD, 67 Gy) at the tumor apex. The 5-year tumor control rate was 94.4%. Tumor recurrence was more frequent in eyes with vitreous tumor cell seeding or fish-flesh regression. The estimated 5-year eye preservation rate was 86.5%. Previous treatment by brachytherapy or external beam radiotherapy, as well as a large tumor diameter, were significant factors for enucleation. The radiotherapy-induced complications after 5 years of follow-up were retinopathy (22%), optic neuropathy (21%), and cataract (17%). These complications were significantly more frequent after prior brachytherapy or external beam radiotherapy. Conclusion: Brachytherapy using {sup 106}Ru plaques is a highly efficient therapy with excellent local tumor control and an acceptable incidence of side effects.

  5. Clinical Practice and Quality Assurance Challenges in Modern Brachytherapy Sources and Dosimetry

    SciTech Connect

    Butler, Wayne M. Merrick, Gregory S.

    2008-05-01

    Modern brachytherapy has led to effective treatments through the establishment of broadly applicable dosimetric thresholds for maximizing survival with minimal morbidity. Proper implementation of recent dosimetric consensus statements and quality assurance procedures is necessary to maintain the established level of safety and efficacy. This review classifies issues as either 'systematic' or 'stochastic' in terms of their impact on large groups or individual patients, respectively. Systematic changes affecting large numbers of patients occur infrequently and include changes in source dosimetric parameters, prescribing practice, dose calculation formalism, and improvements in calculation algorithms. The physicist must be aware of how incipient changes accord with previous experience. Stochastic issues involve procedures that are applied to each patient individually. Although ample guidance for quality assurance of brachytherapy sources exists, some ambiguities remain. The latest American Association of Physicists in Medicine guidance clarifies what is meant by independent assay, changes source sampling recommendations, particularly for sources in sterile strands and sterile preassembled needles, and modifies action level thresholds. The changing environment of brachytherapy has not changed the fact that the prime responsibility for quality assurance in brachytherapy lies with the institutional medical physicist.

  6. Clinical practice and quality assurance challenges in modern brachytherapy sources and dosimetry.

    PubMed

    Butler, Wayne M; Merrick, Gregory S

    2008-01-01

    Modern brachytherapy has led to effective treatments through the establishment of broadly applicable dosimetric thresholds for maximizing survival with minimal morbidity. Proper implementation of recent dosimetric consensus statements and quality assurance procedures is necessary to maintain the established level of safety and efficacy. This review classifies issues as either "systematic" or "stochastic" in terms of their impact on large groups or individual patients, respectively. Systematic changes affecting large numbers of patients occur infrequently and include changes in source dosimetric parameters, prescribing practice, dose calculation formalism, and improvements in calculation algorithms. The physicist must be aware of how incipient changes accord with previous experience. Stochastic issues involve procedures that are applied to each patient individually. Although ample guidance for quality assurance of brachytherapy sources exists, some ambiguities remain. The latest American Association of Physicists in Medicine guidance clarifies what is meant by independent assay, changes source sampling recommendations, particularly for sources in sterile strands and sterile preassembled needles, and modifies action level thresholds. The changing environment of brachytherapy has not changed the fact that the prime responsibility for quality assurance in brachytherapy lies with the institutional medical physicist. PMID:18406914

  7. Effect of photon energy spectrum on dosimetric parameters of brachytherapy sources

    PubMed Central

    Ghorbani, Mahdi; Davenport, David

    2016-01-01

    Abstract Aim The aim of this study is to quantify the influence of the photon energy spectrum of brachytherapy sources on task group No. 43 (TG-43) dosimetric parameters. Background Different photon spectra are used for a specific radionuclide in Monte Carlo simulations of brachytherapy sources. Materials and methods MCNPX code was used to simulate 125I, 103Pd, 169Yb, and 192Ir brachytherapy sources. Air kerma strength per activity, dose rate constant, radial dose function, and two dimensional (2D) anisotropy functions were calculated and isodose curves were plotted for three different photon energy spectra. The references for photon energy spectra were: published papers, Lawrence Berkeley National Laboratory (LBNL), and National Nuclear Data Center (NNDC). The data calculated by these photon energy spectra were compared. Results Dose rate constant values showed a maximum difference of 24.07% for 103Pd source with different photon energy spectra. Radial dose function values based on different spectra were relatively the same. 2D anisotropy function values showed minor differences in most of distances and angles. There was not any detectable difference between the isodose contours. Conclusions Dosimetric parameters obtained with different photon spectra were relatively the same, however it is suggested that more accurate and updated photon energy spectra be used in Monte Carlo simulations. This would allow for calculation of reliable dosimetric data for source modeling and calculation in brachytherapy treatment planning systems. PMID:27247558

  8. ``In Vivo'' Dosimetry in High Dose Rate Brachytherapy for Cervical Cancer Treatments

    NASA Astrophysics Data System (ADS)

    González-Azcorra, S. A.; Mota-García, A.; Poitevín-Chacón, M. A.; Santamaría-Torruco, B. J.; Rodríguez-Ponce, M.; Herrera-Martínez, F. P.; Gamboa de Buen, I.; Ruíz-Trejo, C.; Buenfil, A. E.

    2008-08-01

    In this prospective study, rectal dose was measured "in vivo" using TLD-100 crystals (3×3×1 mm3), and it has been compared to the prescribed dose. Measurements were performed in patients with cervical cancer classified in FIGO stages IB-IIIB and treated with high dose rate brachytherapy (HDR BT) at the Instituto Nacional de Cancerología (INCan).

  9. Novel Use of the Contura for High Dose Rate Cranial Brachytherapy

    SciTech Connect

    Scanderbeg, Daniel J.; Alksne, John F.; Lawson, Joshua D.; Murphy, Kevin T.

    2011-01-01

    A popular choice for treatment of recurrent gliomas was cranial brachytherapy using the GliaSite Radiation Therapy System. However, this device was taken off the market in late 2008, thus leaving a treatment void. This case study presents our experience treating a cranial lesion for the first time using a Contura multilumen, high-dose-rate (HDR) brachytherapy balloon applicator. The patient was a 47-year-old male who was diagnosed with a recurrent right frontal anaplastic oligodendroglioma. Previous radiosurgery made him a good candidate for brachytherapy. An intracavitary HDR balloon brachytherapy device (Contura) was placed in the resection cavity and treated with a single fraction of 20 Gy. The implant, treatment, and removal of the device were all completed without incident. Dosimetry of the device was excellent because the dose conformed very well to the target. V90, V100, V150, and V200 were 98.9%, 95.7%, 27.2, and 8.8 cc, respectively. This patient was treated successfully using the Contura multilumen balloon. Contura was originally designed for deployment in a postlumpectomy breast for treatment by accelerated partial breast irradiation. Being an intracavitary balloon device, its similarity to the GliaSite system makes it a viable replacement candidate. Multiple lumens in the device also make it possible to shape the dose delivered to the target, something not possible before with the GliaSite applicator.

  10. Salvage/Adjuvant Brachytherapy After Ophthalmic Artery Chemosurgery for Intraocular Retinoblastoma

    SciTech Connect

    Francis, Jasmine H.; Barker, Christopher A.; Wolden, Suzanne L.; McCormick, Beryl; Segal, Kira; Cohen, Gil; Gobin, Y. Pierre; Marr, Brian P.; Brodie, Scott E.; Dunkel, Ira J.; Abramson, David H.

    2013-11-01

    Purpose: To evaluate the efficacy and toxicity of brachytherapy after ophthalmic artery chemosurgery (OAC) for retinoblastoma. Methods and Materials: This was a single-arm, retrospective study of 15 eyes in 15 patients treated with OAC followed by brachytherapy at (blinded institution) between May 1, 2006, and December 31, 2012, with a median 19 months' follow-up from plaque insertion. Outcome measurements included patient and ocular survival, visual function, and retinal toxicity measured by electroretinogram (ERG). Results: Brachytherapy was used as adjuvant treatment in 2 eyes and as salvage therapy in 13 eyes of which 12 had localized vitreous seeding. No patients developed metastasis or died of retinoblastoma. The Kaplan-Meier estimate of ocular survival was 79.4% (95% confidence interval 48.7%-92.8%) at 18 months. Three eyes were enucleated, and an additional 6 eyes developed out-of-target volume recurrences, which were controlled with additional treatments. Patients with an ocular complication had a mean interval between last OAC and plaque of 2.5 months (SD 2.3 months), which was statistically less (P=.045) than patients without ocular complication who had a mean interval between last OAC and plaque of 6.5 months (SD 4.4 months). ERG responses from pre- versus postplaque were unchanged or improved in more than half the eyes. Conclusions: Brachytherapy following OAC is effective, even in the presence of vitreous seeding; the majority of eyes maintained stable or improved retinal function following treatment, as assessed by ERG.

  11. Clinical practice and quality assurance challenges in modern brachytherapy sources and dosimetry.

    PubMed

    Butler, Wayne M; Merrick, Gregory S

    2008-01-01

    Modern brachytherapy has led to effective treatments through the establishment of broadly applicable dosimetric thresholds for maximizing survival with minimal morbidity. Proper implementation of recent dosimetric consensus statements and quality assurance procedures is necessary to maintain the established level of safety and efficacy. This review classifies issues as either "systematic" or "stochastic" in terms of their impact on large groups or individual patients, respectively. Systematic changes affecting large numbers of patients occur infrequently and include changes in source dosimetric parameters, prescribing practice, dose calculation formalism, and improvements in calculation algorithms. The physicist must be aware of how incipient changes accord with previous experience. Stochastic issues involve procedures that are applied to each patient individually. Although ample guidance for quality assurance of brachytherapy sources exists, some ambiguities remain. The latest American Association of Physicists in Medicine guidance clarifies what is meant by independent assay, changes source sampling recommendations, particularly for sources in sterile strands and sterile preassembled needles, and modifies action level thresholds. The changing environment of brachytherapy has not changed the fact that the prime responsibility for quality assurance in brachytherapy lies with the institutional medical physicist.

  12. Late rectal complications after prostate brachytherapy for localized prostate cancer: incidence and management.

    PubMed

    Phan, Jack; Swanson, David A; Levy, Lawrence B; Kudchadker, Rajat J; Bruno, Teresa L; Frank, Steven J

    2009-05-01

    This review of the literature on late rectal complications after prostate brachytherapy indicated that it is a highly effective treatment modality for patients with clinically localized prostate cancer but can cause chronic radiation proctitis. The most common manifestation of chronic radiation proctitis was anterior rectal wall bleeding, which often occurred within the first 2 years after brachytherapy. It is interesting to note that the rates of late rectal morbidity appear to have declined over time, which may reflect improvements in implantation techniques and imaging. Rectal biopsy as part of the workup to evaluate rectal bleeding can lead to rectal fistula and the need for colostomy, a rare but major complication. The authors recommend 1) screening colonoscopy before brachytherapy for patients who have not had a screening colonoscopy within the preceding 3 years to rule out colorectal malignancies and, thus, facilitate conservative management should rectal bleeding occur; 2) lifestyle modifications during treatment to limit exposure of the rectum to radiation; and 3) conservative management for rectal bleeding that occurs within 2 years after brachytherapy. Cancer 2009. (c) 2009 American Cancer Society.

  13. Validation of K-edge 125I brachytherapy enhancement with silver compounds.

    PubMed

    Young, L A; Phillips, M H; Nelson, J A

    1999-08-01

    Brachytherapy with radioactive seeds implanted within the tumour volume has demonstrated good success rates in treating certain cancers. In an effort to improve the curative rates in cancer patients, ongoing research is being conducted to enhance the amount of radiation dose that is absorbed within the tumour volume while minimizing the dose absorbed by the surrounding normal tissue. One method for enhancing tumour dose absorption with 125I brachytherapy seeds is to increase the number of photoelectric atomic interactions within the tumour volume by introducing small quantities of a silver compound, taking advantage of the K-edge effect. Because low-energy electrons and Auger electrons are the primary sources of brachytherapy dose enhancement, acquiring accurate experimental measurements of absorbed dose increases is a major challenge. To circumvent this problem, an x ray fluorescence excitation spectroscopy dosimetry technique supplemented with clinically accepted dosimetry calculations was developed to estimate relative absorbed dose increases in a water phantom containing up to 7.5 mM of silver. Excellent agreement was observed between theoretically derived Monte Carlo dosimetric predictions and experimental measurements. These results successfully demonstrated that K-edge enhanced 125I brachytherapy is indeed possible with future development of a non-toxic silver chelate.

  14. Intraluminal brachytherapy in oesophageal cancer: defining its role and introducing the technique

    PubMed Central

    Strnad, Vratislav

    2014-01-01

    Intraluminal brachytherapy plays an important role in the treatment of oesophageal tumours. This article aims to define this role in the curative as well as in the palliative treatment settings drawing on data from the literature, and also emphasizing its potential for harm when used inexpertly. It also provides a short introduction to practical aspects of the treatment procedure and treatment planning. PMID:25097567

  15. Functional assessment of coronary artery disease by intravascular ultrasound and computational fluid dynamics simulation.

    PubMed

    Carrizo, Sebastián; Xie, Xinzhou; Peinado-Peinado, Rafael; Sánchez-Recalde, Angel; Jiménez-Valero, Santiago; Galeote-Garcia, Guillermo; Moreno, Raúl

    2014-10-01

    Clinical trials have shown that functional assessment of coronary stenosis by fractional flow reserve (FFR) improves clinical outcomes. Intravascular ultrasound (IVUS) complements conventional angiography, and is a powerful tool to assess atherosclerotic plaques and to guide percutaneous coronary intervention (PCI). Computational fluid dynamics (CFD) simulation represents a novel method for the functional assessment of coronary flow. A CFD simulation can be calculated from the data normally acquired by IVUS images. A case of coronary heart disease studied with FFR and IVUS, before and after PCI, is presented. A three-dimensional model was constructed based on IVUS images, to which CFD was applied. A discussion of the literature concerning the clinical utility of CFD simulation is provided. PMID:25441999

  16. The expanding indications for virtual histology intravascular ultrasound for plaque analysis prior to carotid stenting.

    PubMed

    Schiro, B J; Wholey, M H

    2008-12-01

    Complications of carotid artery stenting (CAS), including stroke, remain relatively high when compared with carotid endarterectomy (CEA). Current selection criteria for patients undergoing CAS are based predominately on surgical risk related to other comorbidities. Little attention is given to the morphology of the atherosclerotic plaque, although studies have shown that extensive variability exists which confers certain risks for plaque vulnerability. Virtual Histology intravascular ultrasound (VH IVUS) offers a unique method of assessing plaque morphology prior to CAS. Herein, the authors review the concepts of atherosclerotic plaque morphology and discuss the background of VH IVUS and illustrate its use in the carotid system. With selection of the appropriate patient and the appropriate plaque, more favorable outcomes of CAS may be achieved which will solidify its place as a frontline treatment of carotid vascular disease.

  17. Massive haematuria successfully managed by intravesical ankaferd in a haemodialysis patient complicated with disseminated intravascular coagulation

    PubMed Central

    Solak, Yalcin; Gaipov, Abduzhappar; Ozbek, Orhan; Hassan, Mustafa Aziz; Yeksan, Mehdi

    2012-01-01

    Massive haematuria is a life-threatening condition, demanding immediate management of bleeding. The mortality is very high in the case of delayed management of bleeding, especially in elderly patients with concomitant comorbidity. The treatment options of haematuria are wide, and depend on underlying conditions. However, therapeutic choices are limited in the presence of massive and intractable haematuria caused by disseminated intravascular coagulation (DIC). Ankaferd blood stopper (ABS) is a novel, commercially available, haemostatic agent, which has been approved by the Ministry of Health for local use in Turkey. Here, for the first time in the literature, we report a case of diffuse intravesical bleeding stopped by intravesical use of ABS in a 72-year-old man, haemodialysis patient complicated with sepsis and DIC. PMID:23266773

  18. Intravascular low-intensity He-Ne laser irradiation therapy on idiopathic edema

    NASA Astrophysics Data System (ADS)

    Gao, Yunqing; Liu, T. C.; Tang, Xiang-Jun

    1998-11-01

    194 patients with psoriasis were treated by intravascular low level laser irradiation combined with Vit C 2.0g iv and O2 inhale to the nose. An hour once a day, for 5-40 times, and 13.06 times in average, ten times with 4-7 days intervals. The results: cured 23 cases, good effected 61 cases, improved 110 cases, relapsed 10 cases. Curative effect was related to treatment times, cured and good effected 5 times 12.5 percent, 10 times 31 percent, 15 times 94 percent. A matched control group in 17 patients was treated by drug. The results: good effected 1 case, improved 13 cases, not effected 3 cases.

  19. Disseminated intravascular coagulation does not play a major role in the pathogenesis of classical swine fever.

    PubMed

    Blome, Sandra; Meindl-Böhmer, Alexandra; Nowak, Götz; Moennig, Volker

    2013-03-23

    Classical swine fever (CSF) is a multi-systemic disease that can be accompanied by severe haemorrhagic lesions. The underlying pathogenetic mechanisms are still far from being understood, though disseminated intravascular coagulation (DIC) was discussed as a major factor. In the presented study, the direct thrombin inhibitor hirudin was used in an attempt to elucidate the role of the coagulation system in the pathogenesis of CSF-induced haemorrhagic lesions. Two groups of piglets (n=5) were infected with highly virulent CSF virus (CSFV) strain CSF0634. One group underwent daily treatment with hirudin, the other served as untreated challenge infection control. Assessment of clinical signs using a clinical score system, coagulation tests, and blood counts were performed daily. Both groups developed acute-lethal CSF with haemorrhagic lesions. Although changes in the coagulation system were seen in the late stages of CSFV infection, our results strongly suggest that DIC does not present the crucial event in the pathogenesis of haemorrhagic lesions.

  20. Pathogenesis and management of peripartum coagulopathic calamities (disseminated intravascular coagulation and amniotic fluid embolism).

    PubMed

    Levi, Marcel

    2013-01-01

    Acute coagulopathic peripartum calamities are relatively rare but contribute importantly to maternal morbidity and mortality in the Western world. Abruptio placenta, amniotic fluid embolism, and retained fetal or placental material may lead to fulminant intravascular activation of coagulation which results in thromboembolic complications and consumption coagulopathy causing severe hemorrhage. The central underlying pathophysiological pathway in the coagulopathy associated with these syndromes is the occurrence of tissue factor, released from the placenta and amniotic fluid, in the circulation, in combination with low levels of physiological anticoagulant factors during pregnancy. The diagnosis of DIC may be made trough conventional composite scoring systems employing routine coagulation tests, whereas for the diagnosis of amniotic fluid embolism measurement of insulin like growth factor binding protein-1 seems promising. Therapy is aimed at removing the precipitating factor combined with supportive adjunctive treatment options.