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Sample records for breast brachytherapy d-shaped

  1. Brachytherapy in breast cancer: an effective alternative

    Science.gov (United States)

    Chicheł, Adam

    2014-01-01

    Breast conserving surgery (BCS) with following external beam radiation therapy (EBRT) of the conserved breast has become widely accepted in the last decades for the treatment of early invasive breast cancer. The standard technique of EBRT after BCS is to treat the whole breast up to a total dose of 42.5 to 50 Gy. An additional dose is given to treated volume as a boost to a portion of the breast. In the early stage of breast cancer, research has shown that the area requiring radiation treatment to prevent the cancer from local recurrence is the breast tissue that surrounds the area where the initial cancer was removed. Accelerated partial breast irradiation (APBI) is an approach that treats only the lumpectomy bed plus a 1-2 cm margin rather than the whole breast and as a result allows accelerated delivery of the radiation dose in four to five days. There has been a growing interest for APBI and various approaches have been developed under phase I-III clinical studies; these include multicatheter interstitial brachytherapy, balloon catheter brachytherapy, conformal external beam radiation therapy (3D-EBRT) and intra-operative radiation therapy (IORT). Balloon-based brachytherapy approaches include MammoSite, Axxent electronic brachytherapy, Contura, hybrid brachytherapy devices. Another indication for breast brachytherapy is reirradiation of local recurrence after mastectomy. Published results of brachytherapy are very promising. We discuss the current status, indications, and technical aspects of breast cancer brachytherapy. PMID:26327829

  2. Partial breast brachytherapy

    Science.gov (United States)

    ... 11, 2016. www.cancer.gov/types/breast/hp/breast-treatment-pdq . Accessed September 13, 2016. National Cancer Institute. Radiation therapy and you: support for people who have cancer. Cancer.gov Web ...

  3. An Active Mammosite For Breast Brachytherapy

    Science.gov (United States)

    Cudjoe, Thomas

    2006-03-01

    Brachytherapy is an advanced cancer treatment that uses radioactive sources inside or in close proximity to cancerous tumors, thus minimizing exposure to neighboring healthy cells. This radiation oncology treatment unlike many others is localized and precise. The latest involvement of the Brachytherapy research group of the medical physics program at Hampton University is in the development of a scintillator fiber based detector for the breast cancer specific Mammosite (balloon device) from Cytyc Inc. Radioactive sources are inserted into a small plastic catheter (shaft) and pushed at the end of the tube. At that location, a water filled balloon surrounds the source and allow uniform gamma emission into cancer tumors. There is presently no capability for this device to provide measurements of the location of the source, as well as the radiation emitted from the source. Recent data were acquired to evaluate the possibility of measuring the dose distribution during breast Brachytherapy cancer treatments with this device. A high activity ^192Ir radioactive source and a 0.5 and 1 mm^2 scintillating fibers were used. Results will be presented and discussed.

  4. American Brachytherapy Society consensus report for accelerated partial breast irradiation using interstitial multicatheter brachytherapy.

    Science.gov (United States)

    Hepel, Jaroslaw T; Arthur, Douglas; Shaitelman, Simona; Polgár, Csaba; Todor, Dorin; Zoberi, Imran; Kamrava, Mitchell; Major, Tibor; Yashar, Catheryn; Wazer, David E

    To develop a consensus report for the quality practice of accelerated partial breast irradiation (APBI) using interstitial multicatheter brachytherapy (IMB). The American Brachytherapy Society Board appointed an expert panel with clinical and research experience with breast brachytherapy to provide guidance for the current practice of IMB. This report is based on a comprehensive literature review with emphasis on randomized data and expertise of the panel. Randomized trials have demonstrated equivalent efficacy of APBI using IMB compared with whole breast irradiation for select patients with early-stage breast cancer. Several techniques for placement of interstitial catheters are described, and importance of three-dimensional planning with appropriate optimization is reviewed. Optimal target definition is outlined. Commonly used dosing schemas include 50 Gy delivered in pulses of 0.6-0.8 Gy/h using pulsed-dose-rate technique and 34 Gy in 10 fractions, 32 Gy in eight fractions, or 30 Gy in seven fractions using high-dose-rate technique. Potential toxicities and strategies for toxicity avoidance are described in detail. Dosimetric constraints include limiting whole breast volume that receives ≥50% of prescription dose to skin dose to ≤100% of prescription dose (≤60-70% preferred), chest wall dose to ≤125% of prescription dose, Dose Homogeneity Index to >0.75 (>0.85 preferred), V150 Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  5. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Grace L. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Huo, Jinhai [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Giordano, Sharon H. [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hunt, Kelly K. [Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Buchholz, Thomas A. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Smith, Benjamin D., E-mail: bsmith3@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    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

  6. American Brachytherapy Society Task Group Report: Long-term control and toxicity with brachytherapy for localized breast cancer.

    Science.gov (United States)

    Shaitelman, Simona F; Amendola, Beatriz; Khan, Atif; Beriwal, Sushil; Rabinovitch, Rachel; Demanes, D Jeffrey; Kim, Leonard H; Cuttino, Laurie

    There has been significant controversy regarding the equivalency of accelerated partial breast irradiation to whole-breast irradiation. With the recent publication of a large, randomized trial comparing these two treatment modalities, an update on the current state of knowledge of brachytherapy-based accelerated partial breast irradiation, with respect to local control and toxicities, would be useful to practitioners and patients. A systematic literature review was conducted examining articles published between January 2000 and April 2016 on the topics "brachytherapy" and "breast." A total of 67 articles met inclusion criteria, providing outcomes on local tumor control and/or toxicity for breast brachytherapy. Reported 5-year local failure rates were 1.4-6.1% for multicatheter interstitial brachytherapy (MIB) and 0-5.7% for single-entry brachytherapy catheters when delivered to patients with standard selection criteria. Toxicity profiles are acceptable, with cosmetic outcomes comparable to whole-breast irradiation. The reported rates of infection were 0-12%. Symptomatic fat necrosis was found in 0-12% and 0-3.2% of patients treated with MIB and single-entry brachytherapy catheters, respectively. Late Grade ≥3 telangiectasias and fibrosis were reported in 0-8% and 0-9.1% of patients treated with MIB, respectively. These side effects were less common with single-entry brachytherapy catheters (0-2.0% and 0%, respectively). Breast brachytherapy is a treatment technique that provides acceptable rates of local control in select patients, as demonstrated by Level I evidence. The side effect profile of this treatment is well documented and should be shared with patients when considering this treatment modality. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  7. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    Science.gov (United States)

    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 (Agebrachytherapy 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 Agebrachytherapy patients were Agebrachytherapy patients were Endocrine- vs. 44% of WBI patients (P=0.003). Highest absolute 5-year subsequent mastectomy risks occurred in Endocrine−/Agebrachytherapy 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+/Agebrachytherapy vs. WBI and therefore may be useful for selecting appropriate younger brachytherapy candidates. PMID:26279027

  8. Contemporary Toxicity Profile of Breast Brachytherapy Versus External Beam Radiation After Lumpectomy for Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Huo, Jinhai [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Giordano, Sharon H. [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Smith, Benjamin D. [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Shaitelman, Simona F. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Smith, Grace L., E-mail: glsmith@mdanderson.org [Department of Health Services Research, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2016-03-15

    Purpose: We compared toxicities after brachytherapy versus external beam radiation therapy (EBRT) in contemporary breast cancer patients. Methods and Materials: Using MarketScan healthcare claims, we identified 64,112 women treated from 2003 to 2012 with lumpectomy followed by radiation (brachytherapy vs EBRT). Brachytherapy was further classified by multichannel versus single-channel applicator approach. We identified the risks and predictors of 1-year infectious and noninfectious postoperative adverse events using logistic regression and temporal trends using Cochran-Armitage tests. We estimated the 5-year Kaplan-Meier cumulative incidence of radiation-associated adverse events. Results: A total of 4522 (7.1%) patients received brachytherapy (50.2% multichannel vs 48.7% single-channel applicator). The overall risk of infectious adverse events was higher after brachytherapy than after EBRT (odds ratio [OR] = 1.21; 95% confidence interval [CI] 1.09-1.34, P<.001). However, over time, the frequency of infectious adverse events after brachytherapy decreased, from 17.3% in 2003 to 11.6% in 2012, and was stable after EBRT at 9.7%. Beyond 2007, there were no longer excess infections with brachytherapy (P=.97). The overall risk of noninfectious adverse events was higher after brachytherapy than after EBRT (OR=2.27; 95% CI 2.09-2.47, P<.0001). Over time, the frequency of noninfectious adverse events detected increased: after multichannel brachytherapy, from 9.1% in 2004 to 18.9% in 2012 (Ptrend = .64); single-channel brachytherapy, from 12.8% to 29.8% (Ptrend<.001); and EBRT, from 6.1% to 10.3% (Ptrend<.0001). The risk was significantly higher with single-channel than with multichannel brachytherapy (hazard ratio = 1.32; 95% CI 1.03-1.69, P=.03). Of noninfectious adverse events, 70.9% were seroma. Seroma significantly increased breast pain risk (P<.0001). Patients with underlying diabetes, cardiovascular disease, and treatment with chemotherapy had increased

  9. MO-E-BRD-03: Intra-Operative Breast Brachytherapy: Is One Stop Shopping Best? [Non-invasive Image-Guided Breast Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Libby, B. [University of Virginia (United States)

    2015-06-15

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  10. Scintillating fiber optic dosimeters for breast and prostate brachytherapy

    Science.gov (United States)

    Moutinho, L. M.; Castro, I. F.; Freitas, H.; Melo, J.; Silva, P.; Gonçalves, A.; Peralta, L.; Rachinhas, P. J.; Simões, P. C. P. S.; Pinto, S.; Pereira, A.; Santos, J. A. M.; Costa, M.; Veloso, J. F. C. A.

    2017-02-01

    Brachytherapy is a radiotherapy modality where the radioactive material is placed close to the tumor, being a common treatment for skin, breast, gynecological and prostate cancers. These treatments can be of low-dose-rate, using isotopes with mean energy of 30 keV, or high-dose-rate, using isotopes such as 192Ir with a mean energy of 380 keV. Currently these treatments are performed in most cases without in-vivo dosimetry for quality control and quality assurance. We developed a dosimeter using small diameter probes that can be inserted into the patient's body using standard brachytherapy needles. By performing real-time dosimetry in breast and prostate brachytherapy it will be possible to perform real-time dose correction when deviations from the treatment plan are observed. The dosimeter presented in this work was evaluated in-vitro. The studies consisted in the characterization of the dosimeter with 500 μm diameter sensitive probes (with a BCF-12 scintillating optical fiber) using an inhouse made gelatin breast phantom with a volume of 566 cm3. A breast brachytherapy treatment was simulated considering a tumor volume of 27 cm3 and a prescribed absolute dose of 5 Gy. The dose distribution was determined by the Inverse Planning Simulated Annealing (IPSA) optimization algorithm (ELEKTA). The dwell times estimated from the experimental measurements are in agreement with the prescribed dwell times, with relative error below 3%. The measured signal-to-noise ratio (SNR) including the stem-effect contribution is below 3%.

  11. A comparison of complication rates in early-stage breast cancer patients treated with brachytherapy versus whole-breast irradiation.

    Science.gov (United States)

    Ajkay, Nicolas; Collett, Abigail E; Bloomquist, Erica V; Gracely, Edward J; Frazier, Thomas G; Barrio, Andrea V

    2015-04-01

    The adoption of breast brachytherapy into clinical practice for early-stage breast cancer has increased over the last several years. Studies evaluating complication rates following treatment with brachytherapy have shown conflicting results. We compared local toxicity in patients treated with brachytherapy with those treated with whole-breast irradiation (WBI). We identified 417 early-stage breast cancer patients treated with breast-conserving surgery and radiation between 2004 and 2010, and compared 271 women treated with intracavitary brachytherapy with 146 women treated with WBI. Long-term complications were assessed using Kaplan-Meier curves with the log-rank test. Median follow-up was 4.6 years, and the 5-year incidence of infectious skin complications (9.7 vs. 11.0 %, p = 0.84), abscess (1.1 vs. 0 %, p = 0.15), telangiectasia (8.0 vs. 5.3 %, p = 0.35), and breast pain (14.2 vs. 9.4 %, p = 0.2) was similar between the brachytherapy and WBI cohorts. The brachytherapy cohort had a higher 5-year rate of seroma (46.5 vs. 18.5 %, p Brachytherapy patients trended towards more frequent biopsies as a result of fat necrosis to rule out a recurrence (11.2 vs. 6.7 %, p = 0.13). Patients treated with intracavitary brachytherapy had more local toxicity, particularly seroma and fat necrosis. Patients should be counseled on the possible increased rate of long-term complications associated with brachytherapy treatment.

  12. Skin dose in breast brachytherapy: Defining a robust metric.

    Science.gov (United States)

    Hilts, Michelle; Halperin, Heather; Morton, Dan; Batchelar, Deidre; Bachand, Francois; Chowdhury, Rezwan; Crook, Juanita

    2015-01-01

    To define a simple, robust, and relevant metric for measuring skin dose in breast brachytherapy. Postoperative treatment plans (Day 0) for 15 permanent breast seed implant (PBSI) and 10 multicatheter high-dose-rate (MC-HDR) brachytherapy patients were included. Retrospectively, three skin structures were contoured: 2 mm external from the body; and subsurface layers 2 mm and 4 mm thick. Maximum point dose (Dmax), doses to small volumes (e.g., D0.2cc), and the volumes receiving a percentage of the prescription dose (V%, e.g., V66) were calculated. D0.2cc was investigated as a surrogate to the dose given to 1 cm(2) of skin (D1cm(2)). Pearson product-moment correlation (R(2)) was computed between metrics. Observed trends were consistent across brachytherapy technique. V% did not correlate well with any other metrics: median (range) R(2), 0.63 (0.43, 0.77) and 0.69 (0.3, 0.89) for PBSI and MC-HDR, respectively. Dmax was inconsistently correlated across contours and not well correlated with doses to small volumes: median (range) R(2), 0.85 (0.76, 0.93) and 0.88 (0.83, 0.93) for PBSI and MC-HDR, respectively. In contrast, doses to small volumes were consistently well correlated, even across skin layers: D0.1cc vs. D0.2cc median (range) R(2), 0.98 (0.97, 0.99) and 0.97 (0.94, 0.99) for PBSI and MC-HDR, respectively. Doses to small volumes are robust measures of breast skin dose and given skin's strong area effect, D0.2cc for a 2 mm thick skin layer, a simple surrogate of D1cm(2), is recommended for recording skin dose in any breast brachytherapy. Dmax is not robust and should be avoided. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  13. Treatment planning of a skin-sparing conical breast brachytherapy applicator using conventional brachytherapy software

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    Yang Yun; Melhus, Christopher S.; Sioshansi, Shirin; Rivard, Mark J. [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

    2011-03-15

    Purpose: AccuBoost is a noninvasive image-guided technique for the delivery of partial breast irradiation to the tumor bed and currently serves as an alternate to conventional electron beam boost. To irradiate the target volume while providing dose sparing to the skin, the round applicator design was augmented through the addition of an internally truncated conical shield and the reduction of the source to skin distance. Methods: Brachytherapy dose distributions for two types of conical applicators were simulated and estimated using Monte Carlo (MC) methods for radiation transport and a conventional treatment planning system (TPS). MC-derived and TPS-generated dose volume histograms (DVHs) and dose distribution data were compared for both the conical and round applicators for benchmarking purposes. Results: Agreement using the gamma-index test was {>=}99.95% for distance to agreement and dose accuracy criteria of 2 mm and 2%, respectively. After observing good agreement, TPS DVHs and dose distributions for the conical and round applicators were obtained and compared. Brachytherapy dose distributions generated using Pinnacle{sup 3} for ten CT data sets showed that the parallel-opposed beams of the conical applicators provided similar PTV coverage to the round applicators and reduced the maximum dose to skin, chest wall, and lung by up to 27%, 42%, and 43%, respectively. Conclusions: Brachytherapy dose distributions for the conical applicators have been generated using MC methods and entered into the Pinnacle{sup 3} TPS via the Tufts technique. Treatment planning metrics for the conical AccuBoost applicators were significantly improved in comparison to those for conventional electron beam breast boost.

  14. Treatment planning of a skin-sparing conical breast brachytherapy applicator using conventional brachytherapy software.

    Science.gov (United States)

    Yang, Yun; Melhus, Christopher S; Sioshansi, Shirin; Rivard, Mark J

    2011-03-01

    AccuBoost is a noninvasive image-guided technique for the delivery of partial breast irradiation to the tumor bed and currently serves as an alternate to conventional electron beam boost. To irradiate the target volume while providing dose sparing to the skin, the round applicator design was augmented through the addition of an internally truncated conical shield and the reduction of the source to skin distance. Brachytherapy dose distributions for two types of conical applicators were simulated and estimated using Monte Carlo (MC) methods for radiation transport and a conventional treatment planning system (TPS). MC-derived and TPS-generated dose volume histograms (DVHs) and dose distribution data were compared for both the conical and round applicators for benchmarking purposes. Agreement using the gamma-index test was > or = 99.95% for distance to agreement and dose accuracy criteria of 2 mm and 2%, respectively. After observing good agreement, TPS DVHs and dose distributions for the conical and round applicators were obtained and compared. Brachytherapy dose distributions generated using Pinnacle for ten CT data sets showed that the parallel-opposed beams of the conical applicators provided similar PTV coverage to the round applicators and reduced the maximum dose to skin, chest wall, and lung by up to 27%, 42%, and 43%, respectively. Brachytherapy dose distributions for the conical applicators have been generated using MC methods and entered into the Pinnacle TPS via the Tufts technique. Treatment planning metrics for the conical AccuBoost applicators were significantly improved in comparison to those for conventional electron beam breast boost.

  15. MO-E-BRD-00: Breast Brachytherapy: The Phoenix of Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    Is Non-invasive Image-Guided Breast Brachytherapy Good? – Jess Hiatt, MS Non-invasive Image-Guided Breast Brachytherapy (NIBB) is an emerging therapy for breast boost treatments as well as Accelerated Partial Breast Irradiation (APBI) using HDR surface breast brachytherapy. NIBB allows for smaller treatment volumes while maintaining optimal target coverage. Considering the real-time image-guidance and immobilization provided by the NIBB modality, minimal margins around the target tissue are necessary. Accelerated Partial Breast Irradiation in brachytherapy: is shorter better? - Dorin Todor, PhD VCU A review of balloon and strut devices will be provided together with the origins of APBI: the interstitial multi-catheter implant. A dosimetric and radiobiological perspective will help point out the evolution in breast brachytherapy, both in terms of devices and the protocols/clinical trials under which these devices are used. Improvements in imaging, delivery modalities and convenience are among the factors driving the ultrashort fractionation schedules but our understanding of both local control and toxicities associated with various treatments is lagging. A comparison between various schedules, from a radiobiological perspective, will be given together with a critical analysis of the issues. to review and understand the evolution and development of APBI using brachytherapy methods to understand the basis and limitations of radio-biological ‘equivalence’ between fractionation schedules to review commonly used and proposed fractionation schedules Intra-operative breast brachytherapy: Is one stop shopping best?- Bruce Libby, PhD. University of Virginia A review of intraoperative breast brachytherapy will be presented, including the Targit-A and other trials that have used electronic brachytherapy. More modern approaches, in which the lumpectomy procedure is integrated into an APBI workflow, will also be discussed. Learning Objectives: To review past and current

  16. Comparison of accelerated partial breast irradiation via multicatheter interstitial brachytherapy versus whole breast radiation

    Directory of Open Access Journals (Sweden)

    Ferraro Daniel J

    2012-03-01

    Full Text Available Abstract Background Brachytherapy as adjuvant treatment for early-stage breast cancer has become widely available and offers patients an expedited treatment schedule. Given this, many women are electing to undergo brachytherapy in lieu of standard fractionation radiotherapy. We compare outcomes between patients treated with accelerated partial breast irradiation (APBI via multicatheter interstitial brachytherapy versus patients who were also eligible for and offered APBI but who chose whole breast radiation (WBI. Methods Patients treated from December 2002 through May 2007 were reviewed. Selection criteria included patients with pTis-T2N0 disease, ≤ 3 cm unifocal tumors, and negative margins who underwent breast conservation surgery. Local control (LC, cause-specific (CSS and overall survival (OS were analyzed. Results 202 patients were identified in the APBI cohort and 94 patients in the WBI cohort. Median follow-up for both groups exceeded 60 months. LC was 97.0% for the APBI cohort and 96.2% for the WBI cohort at 5 years (ns. Classification by 2010 ASTRO APBI consensus statement categories did not predict worse outcomes. Conclusion APBI via multicatheter interstitial brachytherapy provides similar local failure rates compared to WBI at 5 years for properly selected patients. Excellent results were seen despite the high fraction of younger patients (

  17. Dose estimation for different skin models in interstitial breast brachytherapy

    Science.gov (United States)

    Kabacińska, Renata; Makarewicz, Roman

    2014-01-01

    Purpose Skin is a major organ at risk in breast-conserving therapy (BCT). The American Brachytherapy Society (ABS) recommendations require monitoring of maximum dose received, however, there is no unambiguous way of skin contouring provided. The purpose of this study was to compare the doses received by the skin in different models. Material and methods Standard treatment plans of 20 patients who underwent interstitial breast brachytherapy were analyzed. Every patient had a new treatment plan prepared according to Paris system and had skin contoured in three different ways. The first model, Skin 2 mm, corresponds to the dermatological breast skin thickness and is reaching 2 mm into an external patient contour. It was rejected in a further analysis, because of distinct discontinuities in contouring. The second model, Skin 4 mm, replaced Skin 2 mm, and is reaching 2 mm inside and 2 mm outside of the External contour. The third model, Skin EXT, is created on the External contour and it expands 4 mm outside. Doses received by the most exposed 0.1 cc, 1 cc, 2 cc, and the maximum doses for Skin 4 mm and Skin EXT were compared. Results Mean, median, maximum, and standard deviation of percentage dose difference between Skin EXT and Skin 4 mm for the most exposed 0.1 cc (D0.1cc) of skin were 18.01%, 17.20%, 27.84%, and 4.01%, respectively. All differences were statistically significant (p skin is necessary to avoid complications and obtain a satisfactory cosmetic effect. It is difficult to assess the compatibility of treatment plans with recommendations, while there is no unambiguous way of skin contouring. Especially, if a mean difference of doses between two models of skin contouring is 18% for the most exposed 0.1 cc and can reach almost 28% in some cases. Differences of this magnitude can result in skin complications during BCT. PMID:25097562

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

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    Fendriani, Yoza; Haryanto, Freddy [Nuclear Physics and Biophysics Research Division, FMIPA Institut Teknologi Bandung, Physics Buildings, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    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.

  19. Radiation recall reaction with docetaxel administration after accelerated partial breast irradiation with electronic brachytherapy.

    Science.gov (United States)

    Chen, Sea S; Strauss, Jonathan B; Shah, Anand P; Rao, Ruta D; Bernard, Damien A; Griem, Katherine L

    2009-01-01

    Accelerated partial breast irradiation (APBI) offers several advantages over whole breast irradiation. Electronic brachytherapy may further reduce barriers to breast conserving therapy by making APBI more available. However, its toxicity profile is not well characterized. A 60-year-old woman was treated with APBI using Axxent (Xoft, Sunnyvale, CA) electronic brachytherapy. One month after APBI, a cycle of docetaxel and cyclophosphamide was given. Within 3 weeks, the patient developed an ulcerative radiation recall reaction in the skin overlying the lumpectomy cavity. To investigate this toxicity, the skin dose from electronic brachytherapy was compared with the dose that would have been delivered by an iridium-192 ((192)Ir) source. Additionally, a dose equivalent was estimated by adjusting for the increased relative biologic effectiveness (RBE) of low energy photons generated by the electronic source. Using electronic brachytherapy, the skin dose was 537cGy per fraction compared with 470cGy for an (192)Ir source. Given an RBE for a 40kV source of 1.28 compared with (192)Ir, the equivalent dose at the skin for an electronic source was 687cGy-equivalents, a 46% increase. We present a case of an ulcerative radiation recall reaction in a patient receiving APBI with electronic brachytherapy followed by chemotherapy. Our analysis shows that the use of electronic brachytherapy resulted in the deposition of significantly higher equivalent dose at the skin compared with (192)Ir. These findings suggest that standard guidelines (e.g., surface-to-skin distance) that apply to (192)Ir-based balloon brachytherapy may not be applicable to electronic brachytherapy.

  20. Perioperative high-dose-rate interstitial brachytherapy boost for patients with early breast cancer.

    Science.gov (United States)

    Sharma, Daya Nand; Deo, S V S; Rath, Goura Kisor; Shukla, Nootan Kumar; Thulkar, Sanjay; Madan, Renu; Julka, Pramod Kumar

    2013-01-01

    To evaluate the clinical results of perioperative high-dose-rate interstitial brachytherapy boost treatment preceding whole breast external beam radiation therapy in patients with early breast cancer. From 2005-2010, 100 patients with early breast cancer who met the eligibility criteria were enrolled in the study. Brachytherapy implant was performed during the breast-conserving surgery procedure. The boost treatment was started on the 3rd postoperative day to deliver a dose of 15 Gy in 6 fractions over 3 days. Three weeks later, external beam radiation therapy to the whole breast was started for a prescription dose of 50 Gy. The study end points were local recurrence, acute toxicity and cosmetic outcome. Median age of the patients was 46 years, and median follow-up was 52 months. No patient developed a local recurrence but 5 patients developed distant metastases. The 5-year overall survival and disease-free survival were 86% and 77%, respectively. Eleven patients had acute toxicity; 4 wound complications and 7 grade III skin toxicity. Nine of the 11 patients had breast size of more than 1500 cc. Except for the breast volume (>1500 cc), there was no statistically significant correlation between any of the patient or dosimetry-related factors and acute toxicity. Good-excellent cosmesis was observed in 87% of patients. Perioperative high-dose-rate interstitial brachytherapy boost followed by whole breast external beam radiation therapy provides excellent local control, acceptable acute toxicity and good-excellent breast cosmesis in patients with early breast cancer.

  1. Post-surgical treatment of early-stage breast cancer with electronic brachytherapy: an intersociety, multicenter brachytherapy trial

    Directory of Open Access Journals (Sweden)

    Peter D Beitsch

    2010-10-01

    Full Text Available Peter D Beitsch1, Rakesh R Patel2, John D Lorenzetti3, James C Wurzer4, James C Tucker5, Susan J Laduzinsky6, Morris A Kugler71Dallas Surgical Group, Dallas, TX, USA; 2Valley Medical Oncology Consultants, Pleasanton, CA, USA; 3Breast Specialists, Egg Harbor Township, NJ, USA; 4AtlantiCare Regional Medical Center, Egg Harbor Township, NJ, USA; 5DCH Regional Medical Center – Tuscaloosa, AL, USA; 6Memorial and St Elizabeth’s Cancer Treatment Center, Swansea, IL, USA; 7Southern Illinois Surgical Consultants, Maryville, IL, USAIntroduction: Electronic brachytherapy (EBT was developed to allow accelerated partial breast irradiation to be performed in a patient procedure room with minimal shielding. This observational, nonrandomized, multicenter study evaluated EBT as a post-surgical adjuvant radiation therapy for early stage breast cancer.Methods: This study included women aged 50 years or more with invasive carcinoma or ductal carcinoma in situ, tumor size ≤3 cm, negative lymph node status, and negative surgical margins. The endpoints were skin and subcutaneous toxicities, efficacy outcomes, cosmetic outcomes, and device performance. In this interim report, 1-month, 6-month, and 1-year follow-up data are available on 68, 59, and 37 patients, respectively.Results: The EBT device performed consistently, delivering the prescribed 34 Gy to all 69 patients (10 fractions/patient. Most adverse events were Grade 1 and included firmness, erythema, breast tenderness, hyperpigmentation, pruritis, field contracture, seroma, rash/desquamation, palpable mass, breast edema, hypopigmentation, telangiectasia, and blistering, which were anticipated. Breast infection occurred in 2 (2.9% patients. No tumor recurrences were reported. Cosmetic outcomes were excellent or good in 83.9%–100% of evaluable patients at 1 month, 6 months, and 1 year.Conclusion: This observational, nonrandomized, multicenter study demonstrates that this EBT device was reliable and well

  2. Benefit of Adjuvant Brachytherapy Versus External Beam Radiation for Early Breast Cancer: Impact of Patient Stratification on Breast Preservation

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Grace L. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Jiang, Jing [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Buchholz, Thomas A. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Xu, Ying [Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hoffman, Karen E. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Giordano, Sharon H. [Department of Breast Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Hunt, Kelly K. [Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Smith, Benjamin D., E-mail: bsmith3@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2014-02-01

    Purpose: Brachytherapy after lumpectomy is an increasingly popular breast cancer treatment, but data concerning its effectiveness are conflicting. Recently proposed “suitability” criteria guiding patient selection for brachytherapy have never been empirically validated. Methods: Using the Surveillance, Epidemiology, and End Results–Medicare linked database, we compared women aged 66 years or older with invasive breast cancer (n=28,718) or ductal carcinoma in situ (n=7229) diagnosed from 2002 to 2007, treated with lumpectomy alone, brachytherapy, or external beam radiation therapy (EBRT). The likelihood of breast preservation, measured by subsequent mastectomy risk, was compared by use of multivariate proportional hazards, further stratified by American Society for Radiation Oncology (ASTRO) brachytherapy suitability groups. We compared 1-year postoperative complications using the χ{sup 2} test and 5-year local toxicities using the log-rank test. Results: For patients with invasive cancer, the 5-year subsequent mastectomy risk was 4.7% after lumpectomy alone (95% confidence interval [CI], 4.1%-5.4%), 2.8% after brachytherapy (95% CI, 1.8%-4.3%), and 1.3% after EBRT (95% CI, 1.1%-1.5%) (P<.001). Compared with lumpectomy alone, brachytherapy achieved a more modest reduction in adjusted risk (hazard ratio [HR], 0.61; 95% CI, 0.40-0.94) than achieved with EBRT (HR, 0.22; 95% CI, 0.18-0.28). Relative risks did not differ when stratified by ASTRO suitability group (P=.84 for interaction), although ASTRO “suitable” patients did show a low absolute subsequent mastectomy risk, with a minimal absolute difference in risk after brachytherapy (1.6%; 95% CI, 0.7%-3.5%) versus EBRT (0.8%; 95% CI, 0.6%-1.1%). For patients with ductal carcinoma in situ, EBRT maintained a reduced risk of subsequent mastectomy (HR, 0.40; 95% CI, 0.28-0.55; P<.001), whereas the small number of patients treated with brachytherapy (n=179) precluded definitive comparison with lumpectomy alone

  3. The rationale, technique, and feasibility of partial breast irradiation using noninvasive image-guided breast brachytherapy.

    Science.gov (United States)

    Hepel, Jaroslaw T; Hiatt, Jessica R; Sha, Sandra; Leonard, Kara L; Graves, Theresa A; Wiggins, Doreen L; Mastras, Dean; Pittier, Ann; Wazer, David E

    2014-01-01

    Noninvasive image-guided breast brachytherapy (NIBB) is a novel approach to deliver accelerated partial breast irradiation (APBI). NIBB is noninvasive, yet maintains a high degree of precision by using breast immobilization and image guidance. This makes NIBB an attractive alternative to existing APBI techniques. Forty patients were enrolled to an institutional review board-approved prospective clinical trial evaluating APBI using NIBB. The NIBB technique is described in detail. Briefly, patients were treated with the breast compressed and immobilized sequentially in two orthogonal axes for each fraction. Radiation was delivered using collimated emissions from a high-dose-rate iridium-192 source via specialized applicators. The prescribed dose was 34.0 Gy in 10 fractions. Feasibility and tolerability of treatment were assessed. All patients completed protocol treatment. The median age was 68 years. Sixty-three percent of patients had invasive carcinoma, and 37% had ductal carcinoma in situ. All were node negative. Ninety-three percent of patients were postmenopausal. Mean tumor size, tumor bed volume, and breast volume were 1.1 cm, 22.4 cc, and 1591 cc, respectively. NIBB treatment was well tolerated. Median patient-reported discomfort was 1 on a 10-point pain scale. Treatment delivery times were reasonable. The average treatment time per axis was 14 min (5-20 min), and the average time from start of first treatment axis to completion of orthogonal axis was 43 min (30-63 min). Acute skin toxicity was Grade 0, 1, and 2 in 20%, 53%, and 28% of patients, respectively. There were no Grade 3 or greater acute toxicities observed. NIBB holds promise as an alternative method to deliver APBI. NIBB is feasible and well tolerated by patients. Further investigation of NIBB to deliver APBI is warranted. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  4. A Comparison of Skin Dose Delivered with MammoSite and Multicatheter Breast Brachytherapy

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    Oshaghi M

    2013-12-01

    Full Text Available Background: Accelerated partial breast irradiation via interstitial balloon brachytherapy is a fast and effective treatment method for certain early stage breast cancers however skin, chest wall and Lung doses are correlated with toxicity in patients treated with breast brachytherapy. Objective: To investigate the percentage of the dose received by critical organ (skin, thermoluminescence detector was used in MammoSite brachytherpy and the ability to control skin dose between MammoSite and MultiCatheter brachytherapy was compared with each other. Method: Dosimetry is carried out using a female-equivalent mathematical chest phantom and Ir-192 source for brachytherapy application. Results: Our initial results has shown good agreement with surface doses between those calculated from the treatment planning results and those measured by the thermoluminescence detector. The mean skin dose for the experimental dosimetry in MammoSite was 2.3 Gy (56.76% of prescription dose. Conclusion: The results show that the MultiCatheter method is associated with signifcantly lower mean skin and chest wall dose than is the MammoSite. The MultiCatheter technique is quite flexible and can be applied to any size of breast or lumpectomy cavity, But in MammoSite technique, verifcation of balloon symmetry, balloon/ cavity conformance and overlying skin thickness is essential to assure target coverage and toxicity avoidance.

  5. Brachytherapy in accelerated partial breast irradiation (APBI) – review of treatment methods

    Science.gov (United States)

    Wawrzyniak-Hojczyk, Magdalena; Ambrochowicz, Kinga

    2012-01-01

    Breast conserving surgery (BCS) with following radiotherapy (EBRT) of the conserved breast became widely accepted in the last decades as the treatment of early invasive breast cancer. In an early stage of breast cancer, research has shown that the area requiring radiation treatment to prevent cancer from local recurrence is the breast tissue that surrounds the area where the initial cancer was removed. Accelerated partial breast irradiation (APBI) is an approach that treats only the lumpectomy bed with 1-2 cm margin, rather than the whole breast and as a result allows accelerated delivery of the radiation dose in four to five days. Published results of APBI are very promising. It is evident that APBI will play a role in the management of a selected group of early breast cancer. We discuss current status, indications, technical aspects and recently published results of APBI using different brachytherapy techniques. PMID:23346145

  6. Accelerated partial breast irradiation using multicatheter brachytherapy for select early-stage breast cancer: local control and toxicity

    Directory of Open Access Journals (Sweden)

    Kim Ji-Young

    2010-06-01

    Full Text Available Abstract Background To investigate the efficacy and safety of accelerated partial breast irradiation (APBI via high-dose-rate (HDR multicatheter interstitial brachytherapy for early-stage breast cancer. Methods Between 2002 and 2006, 48 prospectively selected patients with early-stage breast cancer received APBI using multicatheter brachytherapy following breast-conserving surgery. Their median age was 52 years (range 36-78. A median of 34 Gy (range 30-34 in 10 fractions given twice daily within 5 days was delivered to the tumor bed plus a 1-2 cm margin. Most (92% patients received adjuvant systemic treatments. The median follow-up was 53 months (range 36-95. Actuarial local control rate was estimated from surgery using Kaplan-Meier method. Results Local recurrence occurred in two patients. Both were true recurrence/marginal miss and developed in patients with close ( Conclusions APBI using HDR multicatheter brachytherapy yielded local control, toxicity, and cosmesis comparable to those of conventional whole breast irradiation for select early-stage breast cancer. Patients with close resection margins may be ineligible for APBI.

  7. Accelerated partial breast irradiation with brachytherapy: patient selection and technique considerations

    Directory of Open Access Journals (Sweden)

    Trifiletti DM

    2015-07-01

    Full Text Available Daniel M Trifiletti,1 Kara D Romano,1 Shayna L Showalter,2 Kelli A Reardon,1 Bruce Libby,1 Timothy N Showalter11Department of Radiation Oncology, 2Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, VA, USAAbstract: Accelerated partial breast irradiation (APBI through breast brachytherapy is a relatively recent development in breast radiotherapy that has gained international favor because of its reduction in treatment duration and normal tissue irradiation while maintaining favorable cancer-specific and cosmetic outcomes. Despite the fact that several large national trials have not reported final results yet, many providers are currently offering APBI to select patients and APBI is listed as a treatment option for selecting patients in the National Comprehensive Cancer Network guidelines. Multiple consensus guidelines exist in selecting patients for APBI, some with conflicting recommendations. In this review, the existing patient selection guidelines are reported, compared, and critiqued, grouping them in helpful subcategories. Unique patient and technical selection factors for APBI with brachytherapy are explored.Keywords: breast cancer, APBI, breast brachytherapy

  8. Patterns of Use and Short-Term Complications of Breast Brachytherapy in the National Medicare Population From 2008–2009

    Science.gov (United States)

    Presley, Carolyn J.; Soulos, Pamela R.; Herrin, Jeph; Roberts, Kenneth B.; Yu, James B.; Killelea, Brigid; Lesnikoski, Beth-Ann; Long, Jessica B.; Gross, Cary P.

    2012-01-01

    Purpose Brachytherapy has disseminated into clinical practice as an alternative to whole-breast irradiation (WBI) for early-stage breast cancer; however, current national treatment patterns and associated complications remain unknown. Patients and Methods We constructed a national sample of Medicare beneficiaries ages 66 to 94 years who underwent breast-conserving surgery from 2008 to 2009 and were treated with brachytherapy or WBI. We used hospital referral regions (HRRs) to assess national treatment variation and an instrumental variable analysis to compare complication rates between treatment groups, adjusting for patient and clinical characteristics. We compared overall, wound and skin, and deep-tissue and bone complications between brachytherapy and WBI at 1 year of follow-up. Results Of 29,648 women in our sample, 4,671 (15.8%) received brachytherapy. The percent of patients receiving brachytherapy varied substantially across HRRs, ranging from 0% to over 70% (interquartile range, 7.5% to 23.3%). Of women treated with brachytherapy, 34.3% had a complication compared with 27.3% of women undergoing WBI (P brachytherapy (95% CI, 28.6 to 41.9) had a complication compared with 18.4% treated with WBI (95% CI, 15.5 to 21.3; P value for difference, Brachytherapy was associated with a 16.9% higher rate of wound and skin complications compared with WBI (95% CI, 10.0 to 23.9; P Brachytherapy is commonly used among Medicare beneficiaries and varies substantially across regions. After 1 year, wound and skin complications were significantly higher among women receiving brachytherapy compared with those receiving WBI. PMID:23091103

  9. Patterns of use and short-term complications of breast brachytherapy in the national medicare population from 2008-2009.

    Science.gov (United States)

    Presley, Carolyn J; Soulos, Pamela R; Herrin, Jeph; Roberts, Kenneth B; Yu, James B; Killelea, Brigid; Lesnikoski, Beth-Ann; Long, Jessica B; Gross, Cary P

    2012-12-10

    Brachytherapy has disseminated into clinical practice as an alternative to whole-breast irradiation (WBI) for early-stage breast cancer; however, current national treatment patterns and associated complications remain unknown. We constructed a national sample of Medicare beneficiaries ages 66 to 94 years who underwent breast-conserving surgery from 2008 to 2009 and were treated with brachytherapy or WBI. We used hospital referral regions (HRRs) to assess national treatment variation and an instrumental variable analysis to compare complication rates between treatment groups, adjusting for patient and clinical characteristics. We compared overall, wound and skin, and deep-tissue and bone complications between brachytherapy and WBI at 1 year of follow-up. Of 29,648 women in our sample, 4,671 (15.8%) received brachytherapy. The percent of patients receiving brachytherapy varied substantially across HRRs, ranging from 0% to over 70% (interquartile range, 7.5% to 23.3%). Of women treated with brachytherapy, 34.3% had a complication compared with 27.3% of women undergoing WBI (P brachytherapy (95% CI, 28.6 to 41.9) had a complication compared with 18.4% treated with WBI (95% CI, 15.5 to 21.3; P value for difference, Brachytherapy was associated with a 16.9% higher rate of wound and skin complications compared with WBI (95% CI, 10.0 to 23.9; P Brachytherapy is commonly used among Medicare beneficiaries and varies substantially across regions. After 1 year, wound and skin complications were significantly higher among women receiving brachytherapy compared with those receiving WBI.

  10. Radiation exposure of the heart, lung and skin by radiation therapy for breast cancer: a dosimetric comparison between partial breast irradiation using multicatheter brachytherapy and whole breast teletherapy.

    Science.gov (United States)

    Lettmaier, Sebastian; Kreppner, Stephan; Lotter, Michael; Walser, Marc; Ott, Oliver J; Fietkau, Rainer; Strnad, Vratislav

    2011-08-01

    Accelerated partial breast irradiation by means of multicatheter brachytherapy shows great promise in the modern treatment of early breast cancer combining high efficacy in preventing tumour recurrence with low levels of toxicity. The present work attempts a dosimetric comparison between this treatment modality and conventional whole breast external beam radiotherapy by looking at differences in risk organ exposure to radiation. The planning CT data sets of 16 consecutive patients with left-sided breast cancer who received external beam radiotherapy to the whole breast followed by a boost to the tumour bed using multicatheter interstitial brachytherapy after breast conserving surgery were used to create two independent physical treatment plans - one for an external radiotherapy, one for sole partial breast brachytherapy in each case assuming a total reference dose of 50Gy for each patient. Dose-volume parameters D(0.1cc), D(0.5cc), D(1cc,)D(2cc), D(5cc,)D(10cc), D(25cc), D(50cc), V(100), V(90), V(50), V(10), V(5) for the ipsilateral lung, the heart and the adjacent skin were calculated and compared between the two treatment modalities. All organs at risk showed a substantially lower radiation exposure in the brachytherapy plan. This was most pronounced for the heart with values differing by a factor of four. Although somewhat less marked this was also true for the ipsilateral lung and the adjacent skin with exposure ratios of three and two, respectively. With the use of multicatheter interstitial brachytherapy substantial reductions in the radiation exposure of risk organs can be achieved in comparison to whole breast external beam radiotherapy. These are likely to translate into profound clinical benefits. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  11. Accelerated partial breast irradiation using the strut-adjusted volume implant single-entry hybrid catheter in brachytherapy for breast cancer in the setting of breast augmentation.

    Science.gov (United States)

    Bloom, Elizabeth S; Kirsner, Steve; Mason, Bryan E; Nelson, Chris L; Hunt, Kelly K; Baumann, Donald P; Gifford, Kent A

    2011-01-01

    Accelerated partial breast irradiation (APBI) has gained popularity as an alternative to adjuvant whole breast irradiation; however, owing to limitations of delivery devices for brachytherapy, APBI has not been a suitable option for all the patients. This report evaluates APBI using the strut-adjusted volume implant (SAVI) single-entry catheter to deliver brachytherapy for breast cancer in the setting of an augmented breast. The patient previously had placed bilateral subpectoral saline implants; stereotactic core biopsy revealed estrogen receptor- and progesterone receptor-positive ductal carcinoma in situ of intermediate nuclear grade. The patient underwent needle-localized segmental mastectomy of her left breast; pathologic specimen revealed no residual malignancy. An SAVI 8-1 device was placed within the segmental resection cavity. Treatment consisted of 3.4 Gy delivered twice a day for 5 days for a total dose of 34 Gy. Treatments were delivered with a high-dose-rate (192)Ir remote afterloader. Conformance of the device to the lumpectomy cavity was excellent at 99.2%. Dosimetric values of percentage of the planning target volume for evaluation receiving 90% of the prescribed dose, percentage of the planning target volume for evaluation receiving 95% of the prescribed dose, volume receiving 150% of the prescribed dose, and volume receiving 200% of the prescribed dose were 97.1%, 94.6%, 22.7 cc, and 11.6 cc, respectively. Maximum skin dose was 115% of the prescribed dose. The patient tolerated treatment well with excellent cosmetic results, and limited acute and late toxicity at 8 weeks and 6 months, respectively. Breast augmentation should not be an exclusion criterion for the option of APBI. The SAVI single-entry catheter is another option to successfully complete APBI using brachytherapy for breast cancer in the setting of an augmented breast. Copyright © 2011 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  12. Quality control of the breast cancer treatments on Hdr brachytherapy with TLD-100

    Energy Technology Data Exchange (ETDEWEB)

    Torres H, F. [Universidad de Cordoba, Materials and Applied Physics Group, 230002 Monteria, Cordoba (Colombia); De la Espriella V, N. [Universidad de Cordoba, Grupo Avanzado de Materiales y Sistemas Complejos, 230002 Monteria, Cordoba (Colombia); Sanchez C, A., E-mail: franciscotorreshoyos@yahoo.com [Universidad de Cordoba, Departamento de Enfermeria, 230002 Monteria, Cordoba (Colombia)

    2014-07-01

    An anthropomorphic Phantom, a female trunk, was built with a natural bone structure and experimental material coated, glycerin and water-based material called JJT to build soft tissue equivalent to the muscle of human tissue, and a polymer (styrofoam) to build the lung as critical organ to simulate the treatment of breast cancer, with high dose rate brachytherapy (Hdr) and sources of Ir-192. The treatments were planned and calculated for the critical organ: Lung, and injury of 2 cm in diameter in breast with Micro Selectron Hdr system and the software Plato Brachytherapy V 14.1 of the Nucletron (Netherlands) which uses the standard protocol of radiotherapy for brachytherapy treatments. The dose experimentally measured with dosimeters TLD-100 LiF: Mg; Ti, which were previously calibrated, were placed in the same positions and bodies mentioned above, with less than 5% uncertainty. The reading dosimeters was carried out in a Harshaw TLD 4500. The results obtained for calculated treatments, using the standard simulator, and the experimental with TLD-100, show a high concordance, as they are on average a ± 1.1% making process becomes in a quality control of this type of treatments. (Author)

  13. Multicatheter hybrid breast brachytherapy: a potential alternative for patients with inadequate skin distance.

    Science.gov (United States)

    Beriwal, Sushil; Coon, Devin; Kim, Hayeon; Haley, Marsha; Patel, Rakesh; Das, Rupak

    2008-01-01

    The purpose of this study was to determine whether the ClearPath (CP) multicatheter hybrid device was able to achieve acceptable dosimetry in patients in whom the proximity of the breast surgical cavity to the skin precluded treatment with intracavitary MammoSite (MS) brachytherapy. The study consisted of 11 patients who had the MS catheter placed and who were subsequently not treated due to inadequate skin distance. A phantom scan of the CP multicatheter hybrid device was superimposed on the MS CT scan and a dosimetric comparison was performed. The median MS balloon size, diameter, and minimum skin distance were 40 cc, 4.1cm, and 5mm, respectively. The D(90), V(100), V(150), and V(200) with MS vs. CP were 95.29% vs. 97.06%, 88.8% vs. 91.3%, 35.7% vs. 38.0%, and 9.4% vs. 9.6%, respectively. The median maximum skin dose was 5.5 Gy vs. 3.9 Gy (p skin dose significantly without compromising the planning target volume coverage, DHI, or dose to other critical organs. The use of this device has the potential to increase the applicability of accelerated partial breast brachytherapy (APBI) in patients with a surgical cavity close to skin compared with balloon brachytherapy.

  14. Assessment of the implant geometry in fractionated interstitial HDR breast brachytherapy using an electromagnetic tracking system.

    Science.gov (United States)

    Kellermeier, Markus; Fietkau, Rainer; Strnad, Vratislav; Bert, Christoph

    During the partial-breast treatment course by interstitial brachytherapy, electromagnetic tracking (EMT) was applied to measure the implant geometry. Implant-geometry variation, choice of reference data, and three registration methods were assessed. The implant geometry was measured in 28 patients after catheter implantation (EMTbed), during CT imaging (EMTCT), and in each of up to n = 9 treatment fractions (EMTF(k), k = 1, 2,… n). EMTF(k) were registered to the planned implant reconstruction (CTplan) by using all dwell positions (DPs), the button centers, or three fiducial sensors on the patient's skin. Variation in implant geometry obtained from EMTF(k) was assessed for EMTbed, EMTCT, and CTplan. EMT was used to measure 3932 catheters. A duration of 6.5 ± 1.7 min was needed for each implant measurement (mean, 17 catheters) plus setup of the EMT system. Data registration based on the DP deviated significantly lower than registration on button centers or fiducial sensors. Within a registration group, there was a geometry in high-dose-rate interstitial brachytherapy breast treatments. EMTbed, EMTCT, and CTplan data can serve as reference for assessment of implant changes. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  15. High-dose-rate interstitial brachytherapy for accelerated partial breast irradiation – trial results of Azerbaijan National Center of Oncology

    Directory of Open Access Journals (Sweden)

    Jamil A. Aliyev

    2017-04-01

    Full Text Available Purpose : To describe early results of two cohorts of patients with low and intermediate risk of early breast cancer treated with accelerated partial breast irradiation (APBI using different schedules of multicatheter brachytherapy. Material and methods: Patients with early stage breast cancer after breast conserving surgery were enrolled for a prospective analysis. The APBI, using multicatheter brachytherapy, was delivered either eight times 4 Gy in five days with a planned total dose of 32 Gy, or seven times 5 Gy in four days with a planned total dose of 35 Gy. Primary endpoints were side effects. Results : Forty-eight patients were enrolled between 2012 and 2014. Patients characteristics were as follow: median age of patients was 55 years, early breast cancer was defined according GEC-ESTRO recommendations. With a median follow-up period of 37 months, no significant differences regarding late side effects and cosmesis between two cohorts of patients were documented. In total, cosmesis was excellent in 13/48 (27.1% patients, good in 34/48 (70.8% patients, and moderate in 1/48 patient (2.1%. Conclusions : Accelerated partial breast irradiation using multicatheter brachytherapy with 32 Gy/8 fractions and 35 Gy/7 fractions for early breast cancer seems to be similar in terms of late side effects. According to our findings, APBI was also feasible for intermediate-risk of early breast cancer patients.

  16. Manufacture and evaluation of 3-dimensional printed sizing tools for use during intraoperative breast brachytherapy

    Directory of Open Access Journals (Sweden)

    Joshua M. Walker, MD, PhD

    2016-04-01

    Full Text Available Three-dimensional (3D printing has emerged as a promising modality for the production of medical devices. Here we describe the design, production, and implementation of a series of sizing tools for use in an intraoperative breast brachytherapy program. These devices were produced using a commercially available low-cost 3D printer and software, and their implementation resulted in an immediate decrease in consumable costs without affecting the quality of care or the speed of delivery. This work illustrates the potential of 3D printing to revolutionize the field of medical devices, enabling physicians to rapidly develop and prototype novel tools.

  17. Electronic brachytherapy as adjuvant therapy for early stage breast cancer: a retrospective analysis

    Directory of Open Access Journals (Sweden)

    William C Dooley

    2011-01-01

    Full Text Available William C Dooley1, James C Wurzer2, Mohamed Megahy3, Gary Schreiber4, Tapan Roy5, Gary Proulx6, Susan Laduzinsky7, Steven Lane8, James Dalzell9, Kambiz Dowlatshahi10, Dwelvin Simmons11, John P Thropay12, Harish Ahuja13, Peter Beitsch14, Randall W Holt15, Charles A Lee161Oklahoma University Health Sciences Center, Oklahoma City, OK, USA; 2Atlanticare, Egg Harbor Township, NJ, USA; 3Maryville Oncology, Maryville, IL, USA; 4Swedish Covenant Hospital, Chicago, IL, USA; 5Cape Girardeau Cancer Center, Cape Girardeau, MO, USA; 6Exeter Hospital, Exeter, NH, USA; 7St. Elizabeth's Medical Center, Swansea, IL, USA; 8Brockton Hospital, Brockton, MA, USA; 9Nazha Cancer Center, Northfield, NJ, USA; 10Rush University Medical Center, Chicago, IL, USA; 11Florida Radiation Oncology Group, Jacksonville, FL, USA; 12Beverly Oncology and Imaging Center, Montebello, CA, USA; 13Aspirus Cancer Center, Wausau, WI, USA; 14Dallas Surgical Group, Dallas, TX, USA; 15Pacific Crest Medical Physics, Chico, CA, USA; 16Gulf Coast Cancer Treatment Center, Panama City, FL, USAPurpose: This multicenter, retrospective study evaluated treatment and clinical outcomes of patients with early stage breast cancer who received adjuvant high-dose rate (HDR electronic brachytherapy (EBT treatment post-lumpectomy using the Axxent® EBT system. Dosimetric data from the EBT treatment plans were compared with those based on iridium-192 HDR brachytherapy.Material and methods: Medical records of 63 patients with early stage breast cancer (Tis, T1a, T1b, T1c, and T2 who were treated post-lumpectomy with EBT alone or in combination with external beam radiation therapy were reviewed. The prescribed EBT dose was 34 Gy (10 fractions over 5 days, 3.4 Gy each to 1 cm from the balloon surface. Dosimetry data from 12 patients were compared with these of treatment plans using an iridium-192 source prepared for the same 12 patients.Results: The majority of patients (90.5% were older than 50 years and had one

  18. Accelerated partial breast irradiation via brachytherapy: a patterns-of-care analysis with ASTRO consensus statement groupings.

    Science.gov (United States)

    Husain, Zain A; Mahmood, Usama; Hanlon, Alexandra; Neuner, Geoffrey; Buras, Robert; Tkaczuk, Katherine; Feigenberg, Steven J

    2011-01-01

    The 2002 Food and Drug Administration approval of the MammoSite catheter (Hologic, Inc., Beford, MA) led to a surge of interest in accelerated partial breast irradiation (APBI). Until recently, guidelines as to the optimal candidates for this treatment were unavailable. We performed a patterns-of-care analysis for patients undergoing breast brachytherapy and compared these results with the American Society for Radiation Oncology (ASTRO) consensus statement. The Surveillance, Epidemiology, and End Results database was used to examine female breast cancer patients treated with brachytherapy between 2002 and 2007. The patients were then categorized into suitable, cautionary, and unsuitable groups based on the ASTRO guidelines. We identified 4172 female breast cancer patients treated within the stated years. The number of brachytherapy cases increased nearly 10-fold over the time period studied from 163 in 2002 to 1427 in 2007 (pASTRO cautionary or unsuitable groupings. This is the largest patterns-of-care analysis for APBI patients and serves as a baseline for future comparison. Copyright © 2011 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  19. Heterogeneity-corrected vs -uncorrected critical structure maximum point doses in breast balloon brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Leonard, E-mail: kimlh@umdnj.edu [Department of Radiation Oncology, Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ (United States); Narra, Venkat; Yue, Ning [Department of Radiation Oncology, Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, New Brunswick, NJ (United States)

    2013-07-01

    Recent studies have reported potentially clinically meaningful dose differences when heterogeneity correction is used in breast balloon brachytherapy. In this study, we report on the relationship between heterogeneity-corrected and -uncorrected doses for 2 commonly used plan evaluation metrics: maximum point dose to skin surface and maximum point dose to ribs. Maximum point doses to skin surface and ribs were calculated using TG-43 and Varian Acuros for 20 patients treated with breast balloon brachytherapy. The results were plotted against each other and fit with a zero-intercept line. Max skin dose (Acuros) = max skin dose (TG-43) ⁎ 0.930 (R{sup 2} = 0.995). The average magnitude of difference from this relationship was 1.1% (max 2.8%). Max rib dose (Acuros) = max rib dose (TG-43) ⁎ 0.955 (R{sup 2} = 0.9995). The average magnitude of difference from this relationship was 0.7% (max 1.6%). Heterogeneity-corrected maximum point doses to the skin surface and ribs were proportional to TG-43-calculated doses. The average deviation from proportionality was 1%. The proportional relationship suggests that a different metric other than maximum point dose may be needed to obtain a clinical advantage from heterogeneity correction. Alternatively, if maximum point dose continues to be used in recommended limits while incorporating heterogeneity correction, institutions without this capability may be able to accurately estimate these doses by use of a scaling factor.

  20. Heterogeneity-corrected vs -uncorrected critical structure maximum point doses in breast balloon brachytherapy.

    Science.gov (United States)

    Kim, Leonard; Narra, Venkat; Yue, Ning

    2013-01-01

    Recent studies have reported potentially clinically meaningful dose differences when heterogeneity correction is used in breast balloon brachytherapy. In this study, we report on the relationship between heterogeneity-corrected and -uncorrected doses for 2 commonly used plan evaluation metrics: maximum point dose to skin surface and maximum point dose to ribs. Maximum point doses to skin surface and ribs were calculated using TG-43 and Varian Acuros for 20 patients treated with breast balloon brachytherapy. The results were plotted against each other and fit with a zero-intercept line. Max skin dose (Acuros) = max skin dose (TG-43) * 0.930 (R(2) = 0.995). The average magnitude of difference from this relationship was 1.1% (max 2.8%). Max rib dose (Acuros) = max rib dose (TG-43) * 0.955 (R(2) = 0.9995). The average magnitude of difference from this relationship was 0.7% (max 1.6%). Heterogeneity-corrected maximum point doses to the skin surface and ribs were proportional to TG-43-calculated doses. The average deviation from proportionality was 1%. The proportional relationship suggests that a different metric other than maximum point dose may be needed to obtain a clinical advantage from heterogeneity correction. Alternatively, if maximum point dose continues to be used in recommended limits while incorporating heterogeneity correction, institutions without this capability may be able to accurately estimate these doses by use of a scaling factor. Copyright © 2013 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  1. Impact of Insurance Status on Radiation Treatment Modality Selection Among Potential Candidates for Prostate, Breast, or Gynecologic Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Grant, Stephen R. [Baylor College of Medicine, Houston, Texas (United States); Walker, Gary V. [Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Koshy, Matthew [Department of Radiation Oncology, The University of Chicago, Chicago, Illinois (United States); Shaitelman, Simona F.; Klopp, Ann H.; Frank, Steven J.; Pugh, Thomas J.; Allen, Pamela K. [Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States); Mahmood, Usama, E-mail: UMahmood@mdanderson.org [Department of Radiation Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas (United States)

    2015-12-01

    Purpose: The Patient Protection and Affordable Care Act looks to expand both private and Medicaid insurance. To evaluate how these changes may affect the field of radiation oncology, we evaluated the association of insurance status with the use of brachytherapy in cancers for which this treatment technique is used. Methods and Materials: A total of 190,467 patients met the inclusion criteria, of whom 95,292 (50.0%) had breast cancer, 61,096 (32.1%) had prostate cancer, 28,194 (14.8%) had endometrial cancer, and 5885 (3.1%) had cervical cancer. A multivariate logistic regression model was used to determine the association between insurance status and receipt of brachytherapy among patients treated definitively for prostate and cervical cancer or postoperatively for breast and endometrial cancer. Results: The rates of non-Medicaid insurance were 49.9% (cervical), 85.3% (endometrial), 87.4% (breast), and 90.9% (prostate) (P<.001). In a logistic regression, patients who received radiation therapy were less likely to receive brachytherapy if they had Medicaid coverage (odds ratio [OR] 0.57, 95% confidence interval [CI] 0.53-0.61, P<.001) or did not have insurance coverage (OR 0.50, 95% CI 0.45-0.56, P<.001) compared with those with non-Medicaid insurance. On subset analysis, patients with Medicaid coverage or without insurance coverage were significantly less likely to receive brachytherapy than were those with non-Medicaid insurance for all 4 sites, except for patients with endometrial cancer. Conclusions: Despite being a cost-effective treatment modality, brachytherapy is less often used in the definitive or postoperative management of cancer in patients with Medicaid coverage or without insurance. Upcoming health policy changes resulting in the expansion of private insurance and Medicaid will likely increase access to and demand for brachytherapy.

  2. The use of adjuvant high-dose-rate breast brachytherapy in patients with collagen vascular disease: a collaborative experience.

    Science.gov (United States)

    Dragun, Anthony E; Harper, Jennifer L; Olyejar, S Eric; Zunzunegui, Raul G; Wazer, David E

    2011-01-01

    To analyze toxicity and cosmesis in patients with collagen vascular disease (CVD) treated with accelerated partial breast irradiation (APBI) via high-dose-rate (HDR) brachytherapy. This is a pooled analysis of patients with early stage and in situ breast cancer with CVD treated with adjuvant multicatheter or balloon brachytherapy. Physicians at multiple institutions were asked to review their experience and report data regarding toxicity and cosmesis in patients with CVD. All patients fit American Society of Breast Surgeons recommendations for APBI and were treated with HDR brachytherapy with ≥ 3 months followup. Nine cases from five institutions are the subject of this analysis. The median patient age was 54 years and median followup was 31 months. All patients had documented history and active signs/symptoms of rheumatoid arthritis, systemic lupus erythematosis, psoriatic arthritis, or scleroderma. All patients had received medical therapy for CVD in the past, and 78% were under active treatment at the time of brachytherapy. All the patients were treated with multicatheter or balloon (MammoSite [Hologic, Inc., Marlboro, MA], MammoSite ML [Hologic, Inc., Marlboro, MA], or Contura [Senorx, Irvine, CA]) brachytherapy with a median volume of 45.5 cc and a median skin distance of 7.5mm. Acute toxicity included Grade 1 skin erythema (5) and catheter-site wound dehiscence (1). Late toxicity included seroma (5), induration (5), pain (2), telangectasia (2), and superficial infection (1). Cosmesis was excellent or good for all the patients. Women with CVD have a toxicity and cosmesis profile consistent with other APBI series. Although confirmatory data is needed, it may not be necessary to exclude these patients from clinical trials of APBI. Copyright © 2011 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  3. Association between maximal skin dose and breast brachytherapy outcome: a proposal for more rigorous dosimetric constraints.

    Science.gov (United States)

    Cuttino, Laurie W; Heffernan, Jill; Vera, Robyn; Rosu, Mihaela; Ramakrishnan, V Ramesh; Arthur, Douglas W

    2011-11-01

    Multiple investigations have used the skin distance as a surrogate for the skin dose and have shown that distances brachytherapy. No publications have yet described the relationship between the actual maximal skin dose and the outcome. The present study analyzed the maximal skin dose delivered and the occurrence of late toxicity in a large cohort of patients with prolonged follow-up. A total of 96 patients treated with breast brachytherapy between 2000 and 2007 for whom complete planning and follow-up data were available were included in the present analysis. The median follow-up was 48 months (range, 24-111). Of the 96 patients, 40 were treated with multicatheter interstitial brachytherapy and 56 with MammoSite. A multivariate statistical analysis was performed to determine the relationship between several dosimetric parameters and patient outcome. The treatment was well tolerated, with 98% of patients experiencing good to excellent cosmesis. Significant late toxicity was uncommon. The maximal dose delivered to the skin was significantly associated with the incidence of any degree of telangiectasia (p = .009) and moderate to severe fibrosis (p = .010). The incidence of late toxicity was significantly increased when the dose to the skin was >4.05 Gy/fraction. The initial skin dose recommendations have been based on safe use and the avoidance of significant toxicity. The results from the present study have suggested that patients might further benefit if more rigorous constraints were applied and if the skin dose were limited to 120% of the prescription dose. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Dosimetric comparison between intra-cavitary breast brachytherapy techniques for accelerated partial breast irradiation and a novel stereotactic radiotherapy device for breast cancer: GammaPod™

    Science.gov (United States)

    Ödén, Jakob; Toma-Dasu, Iuliana; Yu, Cedric X.; Feigenberg, Steven J.; Regine, William F.; Mutaf, Yildirim D.

    2013-07-01

    The GammaPod™ device, manufactured by Xcision Medical Systems, is a novel stereotactic breast irradiation device. It consists of a hemispherical source carrier containing 36 Cobalt-60 sources, a tungsten collimator with two built-in collimation sizes, a dynamically controlled patient support table and a breast immobilization cup also functioning as the stereotactic frame for the patient. The dosimetric output of the GammaPod™ was modelled using a Monte Carlo based treatment planning system. For the comparison, three-dimensional (3D) models of commonly used intra-cavitary breast brachytherapy techniques utilizing single lumen and multi-lumen balloon as well as peripheral catheter multi-lumen implant devices were created and corresponding 3D dose calculations were performed using the American Association of Physicists in Medicine Task Group-43 formalism. Dose distributions for clinically relevant target volumes were optimized using dosimetric goals set forth in the National Surgical Adjuvant Breast and Bowel Project Protocol B-39. For clinical scenarios assuming similar target sizes and proximity to critical organs, dose coverage, dose fall-off profiles beyond the target and skin doses at given distances beyond the target were calculated for GammaPod™ and compared with the doses achievable by the brachytherapy techniques. The dosimetric goals within the protocol guidelines were fulfilled for all target sizes and irradiation techniques. For central targets, at small distances from the target edge (up to approximately 1 cm) the brachytherapy techniques generally have a steeper dose fall-off gradient compared to GammaPod™ and at longer distances (more than about 1 cm) the relation is generally observed to be opposite. For targets close to the skin, the relative skin doses were considerably lower for GammaPod™ than for any of the brachytherapy techniques. In conclusion, GammaPod™ allows adequate and more uniform dose coverage to centrally and peripherally

  5. Incorporating three-dimensional ultrasound into permanent breast seed implant brachytherapy treatment planning.

    Science.gov (United States)

    Morton, Daniel; Batchelar, Deidre; Hilts, Michelle; Berrang, Tanya; Crook, Juanita

    Planning permanent breast seed implant (PBSI) brachytherapy using CT alone may reduce treatment accuracy because of differences in seroma visualization compared with ultrasound (US). This study evaluates dosimetric effects of seroma delineation in PBSI and the potential impact of incorporating three-dimensional (3D) US into PBSI treatment planning. Spatially coregistered CT and 3D US images from 10 patients were retrospectively analyzed to simulate the PBSI procedure. Seromas contoured on CT and US defined clinical target volumes, CTVCT and CTVUS, which were expanded to create planning target volumes (PTVs). PBSI plans were generated using PTVCT alone, and the resulting coverage to PTVUS was evaluated. To assess the potential impact of transferring to an US-guided procedure, the CT-based plans were centered on CTVUS. The volume encompassed by both PTVs was used to evaluate how 3D US can affect the planning procedure. Median (range) PTVCTV100 was 95.6% (93.3-97.3%), resulting in PTVUS coverage of 91.5% (80.5-97.9%). Centering plans on CTVUS decreased PTVCTV100 by a mean of 10 ± 8%, and increased PTVUSV100 by 5 ± 4%. The combined PTVs were a mean 9±6% larger than PTVCT. Acceptable dosimetry to the combined PTVs resulted in sufficient coverage to individual PTVs but with a mean 11 ± 24% increase to skin dose and 6 ± 8% increase in breast V200. Differences in seroma visualization have dosimetric effects in PBSI. CT-based plans can underdose US-defined volumes and may not adequately translate to an US-guided procedure. Implementing 3D US into planning can potentially compensate for differences in delineation. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  6. Dosimetry evaluation of SAVI-based HDR brachytherapy for partial breast irradiation

    Directory of Open Access Journals (Sweden)

    Manoharan Sivasubramanian

    2010-01-01

    Full Text Available Accelerated partial breast irradiation (APBI with high dose rate (HDR brachytherapy offers an excellent compact course of radiation due to its limited number of fractions for early-stage carcinoma of breast. One of the recent devices is SAVI (strut-adjusted volume implant, which has 6, 8 or 10 peripheral source channels with one center channel. Each channel can be differentially loaded. This paper focuses on the treatment planning, dosimetry and quality assurance aspects of HDR brachytherapy implant with GammaMed Plus HDR afterloader unit. The accelerated PBI balloon devices normally inflate above 35 cc range, and hence these balloon type devices cannot be accommodated in small lumpectomy cavity sizes. CT images were obtained and 3-D dosimetric plans were done with Brachyvision planning system. The 3-D treatment planning and dosimetric data were evaluated with planning target volume (PTV_eval V90, V95, V150, V200 skin dose and minimum distance to skin. With the use of the SAVI 6-1 mini device, we were able to accomplish an excellent coverage - V90, V95, V150 and V200 to 98%, 95%, 37 cc (<50 cc volume and 16 cc (<20 cc volume, respectively. Maximum skin dose was between 73% and 90%, much below the prescribed dose of 34 Gy. The minimum skin distance achieved was 5 to 11 mm. The volume that received 50% of the prescribed radiation dose was found to be lower with SAVI. The multi-channel SAVI-based implants reduced the maximum skin dose to markedly lower levels as compared to other modalities, simultaneously achieving best dose coverage to target volume. Differential-source dwell-loading allows modulation of the radiation dose distribution in symmetric or asymmetric opening of the catheter shapes and is also advantageous in cavities close to chest wall.

  7. Optimal application of the Contura multilumen balloon breast brachytherapy catheter vacuum port to deliver accelerated partial breast irradiation.

    Science.gov (United States)

    Tokita, Kenneth M; Cuttino, Laurie W; Vicini, Frank A; Arthur, Douglas W; Todor, Dorin A; Julian, Thomas B; Lyden, Maureen R

    2011-01-01

    The impact of using the Contura multilumen balloon (MLB) (SenoRx, Inc., Irvine, CA) breast brachytherapy catheter's vacuum port in patients treated with accelerated partial breast irradiation (APBI) was analyzed. Data from 32 patients at two sites were reviewed. Variables analyzed included the seroma fluid (SF):air volume around the MLB before and after vacuum port use and on its ability to improve (1) the eligibility of patients for APBI and (2) dose coverage of the planning target volume for evaluation (PTV_EVAL) in eligible patients. The median SF/air volume before vacuum removal was 6.8 cc vs. 0.8 cc after vacuum removal (median reduction in SF/air volume was 90.5%). Before vacuum port use, the median SF/air volume expressed as percentage of the PTV_EVAL was 7.8% (range, 1.9-26.6) in all patients. After application of the vacuum, this was reduced to 1.2%. Before vacuum port use, 10 (31.3%) patients were not considered acceptable candidates for APBI because the SF/air volume:PTV_EVAL ratio (SF:PTV) was greater than 10% (range, 10.1-26.6%; median, 15.2%). After vacuum port use, the median SF:PTV ratio was 1.6% for a median reduction of 91.5%. In addition, the percentage of the prescribed dose covering greater than or equal to 90% of the PTV_EVAL proportionally increased a median of 8% (range, 3-10%) in eligible patients. Use of the Contura MLB vacuum port significantly improved the conformity of the target tissue to the balloon surface, leading to reproducible dose delivery and increased target volume coverage. In addition, application of the vacuum allowed the safe treatment of unacceptable patients with APBI. Copyright © 2011 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  8. Initial clinical experience with the Strut-Adjusted Volume Implant brachytherapy applicator for accelerated partial breast irradiation.

    Science.gov (United States)

    Yashar, Catheryn M; Blair, Sarah; Wallace, Anne; Scanderbeg, Dan

    2009-01-01

    Accelerated partial breast irradiation is becoming increasingly popular. The Cianna single-entry high-dose-rate applicator, Strut-Adjusted Volume Implant (SAVI, Cianna Medical, Aliso Viejo, CA), contains peripheral struts allowing greater planning flexibility for small-breasted women, technically easier insertion, and normal tissue exposure minimization. This study evaluates early clinical experience. Thirty patients treated with the SAVI with a median followup of 12 months were evaluated. The median age was 59.5. Tumor size averaged 0.9cm. Fifteen cancers were ductal carcinoma in situ (50%), 1 was invasive lobular (3.3%), 4 were tubular (6.7%), and the rest infiltrating ductal (40%). Most of them were estrogen receptor (ER) positive (90%). Nine women (30%) were premenopausal. Dosimetry was outstanding with median V90, V150, and V200 of 96.2%, 24.8, and 12.8cc. There were no symptomatic seromas, and one report of asymptomatic fat necrosis seen on mammogram at 1 year. In patients who had skin spacing of less than 1cm, the median skin dose was 245cGy/fraction. The median rib and lung dose per fraction for those patients with either structure less than 1cm was 340 and 255cGy (75% of prescribed dose), respectively. There have been no local recurrences to date. Early clinical experience with the SAVI demonstrates the ease of placement of a single-entry brachytherapy device combined with the increased dose modulation of interstitial brachytherapy. Dose to normal structures has remained exceedingly low. Almost half of evaluated patients were not candidates for other single-entry brachytherapy devices because of skin spacing or breast size, demonstrating an expansion of candidates for single-entry partial breast brachytherapy.

  9. Ceramic and polymeric devices for breast brachytherapy - Mammographic and CT response

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, Luciana B.; Campos, Tarcisio P.R. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares], e-mail: campos@nuclear.ufmg.br

    2009-07-01

    The present research investigates the radiological visibility of ceramic and polymeric devices implanted in breast phantom (in vitro) for future applications in brachytherapy treatments. The main research goal is to investigate the viability of monitoring ceramic and polymeric devices, in vitro based on simple methods of radiological diagnostic, maintaining the easiest access to the population, represented by the conventional X-ray and mammography. The methodology involves the processing of ceramic devices constituted by bioglasses of Sm, SmBa, Ho, HoBa and the production of polymeric devices, such as polymeric membranes incorporating Ho e HoBa. Contrast agent of Barium was introduced in the syntheses of those devices to improve the radiological visibility in breast equivalent-tissue (TE) phantom. The breast phantom is constituted of glandular, adipose and skin TE, reproducing a 5 cm compressed real breast. In the compressed breast phantom, all types of ceramic and polymeric devices were implanted side by side. Radiological images were generated through X-ray equipment, mammography and computerized tomography (TC), for the samples implanted in the compressed breast phantom. The results show that SmBa and HoBa seeds on breast phantom presented suitable radiological visibility, on all the radiological diagnostic methods. However, the X-rays radiological visibility of Sm seeds without contrast was discreet. On mammography and TC images, it was not possible to identify those seeds, because the same ones were degraded after two months immersed in the glandular TE, after placed on the phantom. The Ho seeds were identified on all radiological diagnostic images, although non contrast agent in its constitution was added. However, the holmium polymeric membranes in direct contact with TE did not show Xray radiological visibility. However, the polymeric membranes of HoBa in the same conditions presented efficient X-rays radiological response. For mammography and TC methods

  10. A dose verification tool for high-dose-rate interstitial brachytherapy treatment planning in accelerated partial breast irradiation.

    Science.gov (United States)

    Marqa, Mohamad Feras; Caudrelier, Jean-Michel; Betrouni, Nacim

    2012-01-01

    To develop a dose verification tool for high-dose-rate interstitial brachytherapy treatment planning in accelerated partial breast irradiation. We have developed a software tool for interstitial brachytherapy treatment planning assessment. The software contains a database of seven (192)Ir source models and is able to estimate the dose distribution using the Task Group 43 and the Sievert integral algorithms. Dose-volume histogram analysis and dose quality assurance (QA) criteria including conformity (COnformal INdex [COIN] and conformation number [CN]), homogeneity (homogeneity index [HI]) parameters were implemented in the software to evaluate and to compare between the doses estimated by the two algorithms and a dose extracted from an external treatment planning system (TPS). The tool was evaluated and validated on four clinical cases treated by high-dose-rate interstitial brachytherapy. The doses provided by the Task Group 43 and the Sievert integral algorithms were evaluated by establishing the dose-volume histogram analysis and then by calculating the QA criteria. The algorithms were validated by comparing the dose at different anatomic points with their corresponding dose points provided from TPS. The differences were considered in good agreement (within 5%). Pretreatment dose verification is an important step in the QA of brachytherapy accelerated partial breast irradiation. A simple, fast, and accurate method of dose verification is therefore needed. The software proposed in this study could fulfill these requirements. In addition, it is freely available for using by anyone wishing to do a QA on any TPS. Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  11. GEC-ESTRO multicenter phase 3-trial: Accelerated partial breast irradiation with interstitial multicatheter brachytherapy versus external beam whole breast irradiation: Early toxicity and patient compliance.

    Science.gov (United States)

    Ott, Oliver J; Strnad, Vratislav; Hildebrandt, Guido; Kauer-Dorner, Daniela; Knauerhase, Hellen; Major, Tibor; Łyczek, Jaroslaw; Guinot, José Luis; Dunst, Jürgen; Miguelez, Cristina Gutierrez; Slampa, Pavel; Allgäuer, Michael; Lössl, Kristina; Polat, Bülent; Kovács, György; Fischedick, Arnt-René; Wendt, Thomas G; Fietkau, Rainer; Kortmann, Rolf-Dieter; Resch, Alexandra; Kulik, Anna; Arribas, Leo; Niehoff, Peter; Guedea, Ferran; Schlamann, Annika; Pötter, Richard; Gall, Christine; Malzer, Martina; Uter, Wolfgang; Polgár, Csaba

    2016-07-01

    To compare early side effects and patient compliance of accelerated partial breast irradiation (APBI) with multicatheter brachytherapy to external beam whole breast irradiation (WBI) in a low-risk group of patients with breast cancer. Between April 2004 and July 2009, 1328 patients with UICC stage 0-IIA breast cancer were randomized to receive WBI with 50Gy and a boost of 10Gy or APBI with either 32.0Gy/8 fractions, or 30.1Gy/7 fractions (HDR-brachytherapy), or 50Gy/0.60-0.80Gy per pulse (PDR-brachytherapy). This report focuses on early side-effects and patient compliance observed in 1186 analyzable patients. ClinicalTrials.gov identifier: NCT00402519. Patient compliance was excellent in both arms. Both WBI and APBI were well tolerated with moderate early side-effects. No grade 4 toxicity had been observed. Grade 3 side effects were exclusively seen for early skin toxicity (radiation dermatitis) with 7% vs. 0.2% (pskin toxicity, 2% vs. 20% (pbrachytherapy was tolerated very well and dramatically reduced early skin toxicity in comparison to standard WBI. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Seed Placement in Permanent Breast Seed Implant Brachytherapy: Are Concerns Over Accuracy Valid?

    Energy Technology Data Exchange (ETDEWEB)

    Morton, Daniel, E-mail: dmorton@bccancer.bc.ca [Department of Medical Physics, BC Cancer Agency, Centre for the Southern Interior, Kelowna, British Columbia (Canada); Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia (Canada); Hilts, Michelle [Department of Medical Physics, BC Cancer Agency, Centre for the Southern Interior, Kelowna, British Columbia (Canada); Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia (Canada); Batchelar, Deidre [Department of Medical Physics, BC Cancer Agency, Centre for the Southern Interior, Kelowna, British Columbia (Canada); Crook, Juanita [Department of Radiation Oncology, BC Cancer Agency, Centre for the Southern Interior, Kelowna, British Columbia (Canada)

    2016-07-01

    Purpose: To evaluate seed placement accuracy in permanent breast seed implant brachytherapy (PBSI), to identify any systematic errors and evaluate their effect on dosimetry. Methods and Materials: Treatment plans and postimplant computed tomography scans for 20 PBSI patients were spatially registered and used to evaluate differences between planned and implanted seed positions, termed seed displacements. For each patient, the mean total and directional seed displacements were determined in both standard room coordinates and in needle coordinates relative to needle insertion angle. Seeds were labeled according to their proximity to the anatomy within the breast, to evaluate the influence of anatomic regions on seed placement. Dosimetry within an evaluative target volume (seroma + 5 mm), skin, breast, and ribs was evaluated to determine the impact of seed placement on the treatment. Results: The overall mean (±SD) difference between implanted and planned positions was 9 ± 5 mm for the aggregate seed population. No significant systematic directional displacements were observed for this whole population. However, for individual patients, systematic displacements were observed, implying that intrapatient offsets occur during the procedure. Mean displacements for seeds in the different anatomic areas were not found to be significantly different from the mean for the entire seed population. However, small directional trends were observed within the anatomy, potentially indicating some bias in the delivery. Despite observed differences between the planned and implanted seed positions, the median (range) V{sub 90} for the 20 patients was 97% (66%-100%), and acceptable dosimetry was achieved for critical structures. Conclusions: No significant trends or systematic errors were observed in the placement of seeds in PBSI, including seeds implanted directly into the seroma. Recorded seed displacements may be related to intrapatient setup adjustments. Despite observed seed

  13. Contura Multi-Lumen Balloon Breast Brachytherapy Catheter: Comparative Dosimetric Findings of a Phase 4 Trial

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Douglas W., E-mail: darthur@mcvh-vcu.edu [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States); Vicini, Frank A. [Michigan Healthcare Professionals/21st Century Oncology, Farmington Hills, Michigan (United States); Todor, Dorin A. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States); Julian, Thomas B. [Allegheny General Hospital, Temple University School of Medicine, Pittsburgh, Pennsylvania (United States); Cuttino, Laurie W.; Mukhopadhyay, Nitai D. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States)

    2013-06-01

    Purpose: Final dosimetric findings of a completed, multi-institutional phase 4 registry trial using the Contura Multi-Lumen Balloon (MLB) breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI) in patients with early-stage breast cancer are presented. Methods and Materials: Three dosimetric plans with identical target coverage were generated for each patient for comparison: multilumen multidwell (MLMD); central-lumen multidwell (CLMD); and central-lumen single-dwell (CLSD) loading of the Contura catheter. For this study, a successful treatment plan achieved ideal dosimetric goals and included the following: ≥95% of the prescribed dose (PD) covering ≥95% of the target volume (TV); maximum skin dose ≤125% of the PD; maximum rib dose ≤145% of the PD; and V150 ≤50 cc and V200 ≤10 cc. Results: Between January 2008 and February 2011, 23 institutions participated. A total of 318 patients were available for dosimetric review. Using the Contura MLB, all dosimetric criteria were met in 78.93% of cases planned with MLMD versus 55.38% with the CLMD versus 37.66% with the CLSD (P≤.0001). Evaluating all patients with the full range of skin to balloon distance represented, median maximum skin dose was reduced by 12% and median maximum rib dose by 13.9% when using MLMD-based dosimetric plans compared to CLSD. The dosimetric benefit of MLMD was further demonstrated in the subgroup of patients where skin thickness was <5 mm, where MLMD use allowed a 38% reduction in median maximum skin dose over CLSD. For patients with rib distance <5 mm, the median maximum rib dose reduction was 27%. Conclusions: Use of the Contura MLB catheter produced statistically significant improvements in dosimetric capabilities between CLSD and CLMD treatments. This device approach demonstrates the ability not only to overcome the barriers of limited skin thickness and close rib proximity, but to consistently achieve a higher standard of dosimetric planning goals.

  14. Initial clinical experience with multilumen brachytherapy catheters for accelerated partial breast irradiation.

    Science.gov (United States)

    Shah, Chirag; Ghilezan, Mihai; Arthur, Douglas; Wilkinson, John B; Keisch, Martin; Chen, Peter; Vicini, Frank A

    2012-01-01

    To review the initial experience of three institutions using multilumen catheters to deliver accelerated partial breast irradiation (APBI) and evaluate dosimetric improvements. Patients were eligible for this analysis if they met criteria for accelerated partial breast irradiation at their respective institution and were not enrolled on the national Phase III trial. Minimum guidelines for treatment planning from the National Surgical Adjuvant Breast and Bowel Project B-39/Radiation Therapy Oncology Group 0413 protocol were followed. Toxicities were coded using common toxicity criteria version 3.0 criteria. Sixty-two patients were analyzed as part of this study. Median skin spacing was 11mm with a median skin dose of 86.9% (% of prescription dose [PD]). Median rib dose was 76.1% of the PD (range, 4.3-155.7%). The V(90), V(95), and V(100) of the PD for the planning target volume evaluation was 95.4%, 95.2%, and 80.3%, respectively. Seven patients had both skin and rib spacing skin dose and rib dose being 113.4% and 130.9% of the PD. For these cases, the median V(90), V(95), and V(100) of the PD was 99.2%, 94.3%, and 81.1%, respectively, whereas the median V(150) and V(200) were 22.5cc and 7.4cc. Overall, Grade I and II radiation dermatitis were noted in 41.9% and 6.5% of patients. The multilumen device led to improvements in target coverage and normal structure doses compared with traditionally accepted guidelines. Similar toxicities were seen compared with single-lumen devices, even in patients with skin and rib spacing Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  15. Feasibility and full-course dosimetry of an intraoperatively placed multichannel brachytherapy catheter for accelerated partial breast irradiation.

    Science.gov (United States)

    Stish, Bradley J; Pafundi, Deanna H; Hieken, Tina J; Whitaker, Thomas J; Furutani, Keith M; Jakub, James W; Boughey, Judy C; Degnim, Amy C; McLemore, Luke B; Mou, Benjamin; Mutter, Robert W; Park, Sean S

    Determine feasibility and resultant dosimetry of an intraoperatively placed multichannel intracavitary brachytherapy catheter for accelerated partial breast irradiation (APBI). Patients with breast cancer underwent intraoperative brachytherapy catheter placement based on frozen section analysis with immediate postoperative APBI. The planning target volume evaluation (PTVEval) and organs at risk were contoured on daily pretreatment CT scans for each patient, and the original treatment plan was applied to assess full-course dosimetry. Of the first 21 patients consented for intraoperative catheter placement, 20 (95%) were able to proceed with treatment as planned. The mean volume of PTVEval receiving 90% of prescription dose (V90%) and mean percentage of prescription dose to 90% of the PTVEval (D90%) on initial planning were 96.7 (±1.1%) and 100.2 (±2.1%), respectively. Full-course dose coverage remained excellent with a mean PTVEval V90% and D90% of 95.0 (±4.4%) and 100.2 (±9.6%), respectively. Mean full-course maximum dose constraints for chest wall and skin were met by 70% and 95% of patients, respectively. Air accumulation >1 cc during treatment increased the risk of a daily fraction with PTVEval coverage below goal (odds ratio, 9.8; p = 0.05), whereas those with applicators Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  16. Patient-specific Monte Carlo dose calculations for 103Pd breast brachytherapy

    Science.gov (United States)

    Miksys, N.; Cygler, J. E.; Caudrelier, J. M.; Thomson, R. M.

    2016-04-01

    This work retrospectively investigates patient-specific Monte Carlo (MC) dose calculations for 103Pd permanent implant breast brachytherapy, exploring various necessary assumptions for deriving virtual patient models: post-implant CT image metallic artifact reduction (MAR), tissue assignment schemes (TAS), and elemental tissue compositions. Three MAR methods (thresholding, 3D median filter, virtual sinogram) are applied to CT images; resulting images are compared to each other and to uncorrected images. Virtual patient models are then derived by application of different TAS ranging from TG-186 basic recommendations (mixed adipose and gland tissue at uniform literature-derived density) to detailed schemes (segmented adipose and gland with CT-derived densities). For detailed schemes, alternate mass density segmentation thresholds between adipose and gland are considered. Several literature-derived elemental compositions for adipose, gland and skin are compared. MC models derived from uncorrected CT images can yield large errors in dose calculations especially when used with detailed TAS. Differences in MAR method result in large differences in local doses when variations in CT number cause differences in tissue assignment. Between different MAR models (same TAS), PTV {{D}90} and skin {{D}1~\\text{c{{\\text{m}}3}}} each vary by up to 6%. Basic TAS (mixed adipose/gland tissue) generally yield higher dose metrics than detailed segmented schemes: PTV {{D}90} and skin {{D}1~\\text{c{{\\text{m}}3}}} are higher by up to 13% and 9% respectively. Employing alternate adipose, gland and skin elemental compositions can cause variations in PTV {{D}90} of up to 11% and skin {{D}1~\\text{c{{\\text{m}}3}}} of up to 30%. Overall, AAPM TG-43 overestimates dose to the PTV ({{D}90} on average 10% and up to 27%) and underestimates dose to the skin ({{D}1~\\text{c{{\\text{m}}3}}} on average 29% and up to 48%) compared to the various MC models derived using the post-MAR CT images studied

  17. Patient-specific Monte Carlo dose calculations for (103)Pd breast brachytherapy.

    Science.gov (United States)

    Miksys, N; Cygler, J E; Caudrelier, J M; Thomson, R M

    2016-04-07

    This work retrospectively investigates patient-specific Monte Carlo (MC) dose calculations for (103)Pd permanent implant breast brachytherapy, exploring various necessary assumptions for deriving virtual patient models: post-implant CT image metallic artifact reduction (MAR), tissue assignment schemes (TAS), and elemental tissue compositions. Three MAR methods (thresholding, 3D median filter, virtual sinogram) are applied to CT images; resulting images are compared to each other and to uncorrected images. Virtual patient models are then derived by application of different TAS ranging from TG-186 basic recommendations (mixed adipose and gland tissue at uniform literature-derived density) to detailed schemes (segmented adipose and gland with CT-derived densities). For detailed schemes, alternate mass density segmentation thresholds between adipose and gland are considered. Several literature-derived elemental compositions for adipose, gland and skin are compared. MC models derived from uncorrected CT images can yield large errors in dose calculations especially when used with detailed TAS. Differences in MAR method result in large differences in local doses when variations in CT number cause differences in tissue assignment. Between different MAR models (same TAS), PTV [Formula: see text] and skin [Formula: see text] each vary by up to 6%. Basic TAS (mixed adipose/gland tissue) generally yield higher dose metrics than detailed segmented schemes: PTV [Formula: see text] and skin [Formula: see text] are higher by up to 13% and 9% respectively. Employing alternate adipose, gland and skin elemental compositions can cause variations in PTV [Formula: see text] of up to 11% and skin [Formula: see text] of up to 30%. Overall, AAPM TG-43 overestimates dose to the PTV ([Formula: see text] on average 10% and up to 27%) and underestimates dose to the skin ([Formula: see text] on average 29% and up to 48%) compared to the various MC models derived using the post-MAR CT images

  18. Dosimetric optimization of a conical breast brachytherapy applicator for improved skin dose sparing

    Energy Technology Data Exchange (ETDEWEB)

    Yang Yun; Rivard, Mark J. [Biomedical Engineering and Biotechnology, University of Massachusetts Lowell, Lowell, Massachusetts 01854 (United States); Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

    2010-11-15

    Purpose: Both the AccuBoost D-shaped and round applicators have been dosimetrically characterized and clinically used to treat patients with breast cancer. While the round applicators provide conformal dose coverage, under certain clinical circumstances the breast skin dose may be higher than preferred. The purpose of this study was to modify the round applicators to minimize skin dose while not substantially affecting dose uniformity within the target volume and reducing the treatment time. Methods: In order to irradiate the intended volume while sparing critical structures such as the skin, the current round applicator design has been augmented through the addition of an internal truncated cone (i.e., frustum) shield. Monte Carlo methods and clinical constraints were used to design the optimal cone applicator. With the cone applicator now defined as the entire assembly including the surrounding tungsten-alloy shell holding the HDR {sup 192}Ir source catheter, the applicator height was reduced to diminish the treatment time while minimizing skin dose. Monte Carlo simulation results were validated using both radiochromic film and ionization chamber measurements based on established techniques. Results: The optimal cone applicators diminished the maximum skin dose by 15%-32% (based on the applicator diameter and breast separation) with the tumor dose reduced by less than 3% for a constant exposure time. Furthermore, reduction in applicator height diminished the treatment time by up to 30%. Radiochromic film and ionization chamber dosimetric results in phantom agreed with Monte Carlo simulation results typically within 3%. Larger differences were outside the treatment volume in low dose regions or associated with differences between the measurement and Monte Carlo simulation environments. Conclusions: A new radiotherapy treatment device was developed and dosimetrically characterized. This set of applicators significantly reduces the skin dose and treatment time while

  19. Dosimetric optimization of a conical breast brachytherapy applicator for improved skin dose sparing.

    Science.gov (United States)

    Yang, Yun; Rivard, Mark J

    2010-11-01

    Both the AccuBoost D-shaped and round applicators have been dosimetrically characterized and clinically used to treat patients with breast cancer. While the round applicators provide conformal dose coverage, under certain clinical circumstances the breast skin dose may be higher than preferred. The purpose of this study was to modify the round applicators to minimize skin dose while not substantially affecting dose uniformity within the target volume and reducing the treatment time. In order to irradiate the intended volume while sparing critical structures such as the skin, the current round applicator design has been augmented through the addition of an internal truncated cone (i.e., frustum) shield. Monte Carlo methods and clinical constraints were used to design the optimal cone applicator. With the cone applicator now defined as the entire assembly including the surrounding tungsten-alloy shell holding the HDR 192Ir source catheter, the applicator height was reduced to diminish the treatment time while minimizing skin dose. Monte Carlo simulation results were validated using both radiochromic film and ionization chamber measurements based on established techniques. The optimal cone applicators diminished the maximum skin dose by 15%-32% (based on the applicator diameter and breast separation) with the tumor dose reduced by less than 3% for a constant exposure time. Furthermore, reduction in applicator height diminished the treatment time by up to 30%. Radiochromic film and ionization chamber dosimetric results in phantom agreed with Monte Carlo simulation results typically within 3%. Larger differences were outside the treatment volume in low dose regions or associated with differences between the measurement and Monte Carlo simulation environments. A new radiotherapy treatment device was developed and dosimetrically characterized. This set of applicators significantly reduces the skin dose and treatment time while retaining uniform target dose.

  20. Clinical Significance of Accounting for Tissue Heterogeneity in Permanent Breast Seed Implant Brachytherapy Planning.

    Science.gov (United States)

    Mashouf, Shahram; Fleury, Emmanuelle; Lai, Priscilla; Merino, Tomas; Lechtman, Eli; Kiss, Alex; McCann, Claire; Pignol, Jean-Philippe

    2016-03-15

    The inhomogeneity correction factor (ICF) method provides heterogeneity correction for the fast calculation TG43 formalism in seed brachytherapy. This study compared ICF-corrected plans to their standard TG43 counterparts, looking at their capacity to assess inadequate coverage and/or risk of any skin toxicities for patients who received permanent breast seed implant (PBSI). Two-month postimplant computed tomography scans and plans of 140 PBSI patients were used to calculate dose distributions by using the TG43 and the ICF methods. Multiple dose-volume histogram (DVH) parameters of clinical target volume (CTV) and skin were extracted and compared for both ICF and TG43 dose distributions. Short-term (desquamation and erythema) and long-term (telangiectasia) skin toxicity data were available on 125 and 110 of the patients, respectively, at the time of the study. The predictive value of each DVH parameter of skin was evaluated using the area under the receiver operating characteristic (ROC) curve for each toxicity endpoint. Dose-volume histogram parameters of CTV, calculated using the ICF method, showed an overall decrease compared to TG43, whereas those of skin showed an increase, confirming previously reported findings of the impact of heterogeneity with low-energy sources. The ICF methodology enabled us to distinguish patients for whom the CTV V100 and V90 are up to 19% lower compared to TG43, which could present a risk of recurrence not detected when heterogeneity are not accounted for. The ICF method also led to an increase in the prediction of desquamation, erythema, and telangiectasia for 91% of skin DVH parameters studied. The ICF methodology has the advantage of distinguishing any inadequate dose coverage of CTV due to breast heterogeneity, which can be missed by TG43. Use of ICF correction also led to an increase in prediction accuracy of skin toxicities in most cases. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Breast conservation surgery and interstitial brachytherapy in the management of locally recurrent carcinoma of the breast: the Allegheny General Hospital experience.

    Science.gov (United States)

    Trombetta, Mark; Julian, Thomas; Bhandari, Tanuja; Werts, E Day; Miften, Moyed; Parda, David

    2008-01-01

    To evaluate lumpectomy followed by interstitial brachytherapy as an acceptable salvage therapy for women who have developed localized recurrence of breast cancer after conservation surgery and postoperative external radiotherapy. Between 1/1998 and 10/2006, 21 patients with T0 or T1 in-breast recurrence of carcinoma were offered interstitial low-dose rate brachytherapy after tumor re-excision as an alternative to salvage mastectomy. All patients had failed lumpectomy followed by standard postoperative external beam radiotherapy (range, 5000-6040cGy) as treatment for the initial breast carcinoma. Seven recurred as ductal carcinoma in situ, 2 as infiltrating lobular carcinoma, and 12 as recurrent invasive carcinoma. The recurrent tumors were excised with final margins of resection free of residual disease per National Surgical Adjuvant Breast and Bowel Project definition. Tumor bed implantation was then carried out with an interstitial technique using (192)Ir with the target volume consisting of the tumor bed plus a minimum 1.0-cm clinical margin. The required minimum dose delivered to the target volume was 4500-5000cGy (range, 4500-5530). Twenty of 21 patients were free of local disease with a median observation time of 40 months (range, 3-69). The single patient who developed a second local recurrence was treated successfully with simple mastectomy. Two patients succumbed to systemic disease at 17 and 24 months after salvage implant therapy. One patient developed a contralateral breast cancer. Cosmetic results defined by the National Surgical Adjuvant Breast and Bowel Project cosmesis scale were acceptable. One patient developed a localized seroma requiring multiple needle aspirations before complete resolution. Two patients developed localized skin breakdown in the tumor bed. One healed after 6 months of conservative treatment. The other healed 9 months later with Grade II cosmesis. This patient also developed a concurrent postoperative wound infection. Repeat

  2. Cosmetic effect in patients with early breast cancer treated with breast conserving therapy (BCT) and with HDR brachytherapy (HDR-BT) “boost”

    Science.gov (United States)

    Łyczek, Jarosław; Kawczyn´ska, Maria; Gruszczyn´ska, Ewelina

    2009-01-01

    Purpose The estimation of cosmetic effect in 93 patients with early breast cancer treated with breast conserving surgery (BCS) followed by combined radiotherapy, including HDR brachytherapy (HDR-BT) boost. Material and methods After BCS (tumorectomy or quadrantectomy) external beam radiation therapy (EBRT) was used in total dose of 50 Gy for the whole breast. Tumor bed was localized basing on clinical and mammographic preoperative examinations and histopathology evaluation. 10 Gy in one fraction was applied to all patients using HDR-BT. Steel interstitial needles stabilized by plastic templates were used. 192-Ir with 10 Ci nominal activity and HDR-GammaMed 12i unit (Mick Radio-Nuclear Instruments, Inc., Mt. Vernon, NY) and ABACUS software were used. 31 patients received additional chemotherapy. Cosmetic effect was evaluated in 36 month after the end of brachytherapy treatment basing on modified EORTC scale. For statistical analysis the rang of correlation test, contingent test, linear regression test and ProbRough rulet induction test were used. Results and Conclusions HDR-BT tolerance was good in most of the cases. Excellent and very good cosmetic effect was observed in 79 patients (85%). Statistically important correlations between following examined prognostic factors and cosmetics outcome were observed: clinical and mammographic tumor estimation, method of breast conserving surgery, type of skin incision, number of interstitial applicators, irradiated reference volume (PTV) and type of optimization method. No correlations with cosmetics effect were found in factors such as: age of patients, location of tumor or additional therapy. PMID:27795716

  3. Cosmetic Analysis Following Breast-Conserving Surgery and Adjuvant High-Dose-Rate Interstitial Brachytherapy for Early-Stage Breast Cancer: A Prospective Clinical Study

    Energy Technology Data Exchange (ETDEWEB)

    Garsa, Adam A.; Ferraro, Daniel J.; DeWees, Todd [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Margenthaler, Julie A. [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Naughton, Michael [Department of Medicine, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Aft, Rebecca [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Department of Surgery, John Cochran Veterans Hospital, St. Louis, Missouri (United States); Gillanders, William E.; Eberlein, Timothy [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Matesa, Melissa A. [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Zoberi, Imran, E-mail: izoberi@radonc.wustl.edu [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States)

    2013-03-15

    Purpose: To prospectively evaluate cosmetic outcomes in women treated with accelerated partial breast irradiation using high-dose-rate interstitial brachytherapy for early-stage breast cancer. Methods and Materials: Between 2004 and 2008, 151 patients with early-stage breast cancer were enrolled in a phase 2 prospective clinical trial. Eligible patients had stage Tis-T2 tumors of ≤3 cm that were excised with negative margins and with no nodal involvement. Patients received 3.4 Gy twice daily to a total dose of 34 Gy. Both the patients and the treating radiation oncologist qualitatively rated cosmesis as excellent, good, fair, or poor over time and ascribed a cause for changes in cosmesis. Cosmetic outcome was evaluated quantitatively by percentage of breast retraction assessment (pBRA). Patients also reported their satisfaction with treatment over time. Results: Median follow-up was 55 months. The rates of excellent-to-good cosmesis reported by patients and the treating radiation oncologist were 92% and 97% pretreatment, 91% and 97% at 3 to 4 months' follow-up, 87% and 94% at 2 years, and 92% and 94% at 3 years, respectively. Breast infection and adjuvant chemotherapy were independent predictors of a fair-to-poor cosmetic outcome at 3 years. Compared to pretreatment pBRA (7.35), there was no significant change in pBRA over time. The volume receiving more than 150 Gy (V150) was the only significant predictor of pBRA. The majority of patients (86.6%) were completely satisfied with their treatment. Conclusions: Patients and the treating physician reported a high rate of excellent-to-good cosmetic outcomes at all follow-up time points. Acute breast infection and chemotherapy were associated with worse cosmetic outcomes. Multicatheter interstitial brachytherapy does not significantly change breast size as measured by pBRA.

  4. A multi-institutional study of feasibility, implementation, and early clinical results with noninvasive breast brachytherapy for tumor bed boost.

    Science.gov (United States)

    Hamid, Subarna; Rocchio, Kathy; Arthur, Douglas; Vera, Robyn; Sha, Sandra; Jolly, Michele; Cavanaugh, Sean; Wooten, Eric; Benda, Rashmi; Greenfield, Brad; Prestidge, Bradley; Ackerman, Scot; Kuske, Robert; Quiet, Coral; Snyder, Margaret; Wazer, David E

    2012-08-01

    To evaluate the feasibility, implementation, and early results of noninvasive breast brachytherapy (NIBB) for tumor bed boost with whole breast radiation therapy (WBRT). NIBB is a commercially available (AccuBoost, Billerica, MA) mammography-based, brachytherapy system in which the treatment applicators are centered on the planning target volume (PTV) to direct (192)Ir emissions along orthogonal axes. A privacy-encrypted online data registry collected information from 8 independent academic and community-based institutions. Data were from 146 consecutive women with early-stage breast cancer after lumpectomy and WBRT receiving boost with NIBB between July 2007 and March 2010. Toxicity and cosmesis were graded according to the Common Toxicity Criteria (v. 3.0) and the Harvard scale. Median follow-up was 6 months (1-39 months). Grade 1-2 skin toxicity was observed in 64%, 48%, and 21% during the acute (1-3 weeks), intermediate (4-26 weeks), and late-intermediate (>26 weeks) periods. There was no Grade 4 toxicity. At 6 months, for the entire cohort, cosmesis was excellent/good in 62%/38%. The subset receiving NIBB before WBRT had cosmetic scores of 32% and 63%, whereas during WBRT, 58% and 37% were rated as excellent and good, respectively. Breast compression was scored as "uncomfortable" in 12%, 29%, and 59% when NIBB was delivered before, during, or after WBRT. For each patient, the fraction-to-fraction variability in PTV was low. Skin flash was associated with a higher proportion of excellent cosmesis (58% vs. 42%) relative to having the applicator all within breast tissue. These data indicate that NIBB is feasible and can be consistently implemented in a broad array of practice settings. Preliminary evaluation suggests that NIBB is associated with acceptably mild normal tissue toxicity and favorable early cosmesis. The application of NIBB before WBRT may be associated with better patient tolerance at the expense of less favorable cosmetic outcome. Copyright © 2012

  5. Impact of interfraction seroma collection on breast brachytherapy dosimetry - a mathematical model.

    Science.gov (United States)

    Bhatt, Aashish; Sowards, Keith; Bhatt, Geetika; Freeman, Andrew; Dragun, Anthony

    2012-06-01

    Balloon brachytherapy is a widely accepted modality for delivery of accelerated partial breast irradiation (APBI). Our hypothesis was that inter-fraction seroma collection around the balloon surface would have an adverse effect on dosimetry of the target. This is a dosimetric re-planning study using two volumetric models (30 cc and 45 cc) in a Contura(®) multi-lumen balloon (MLB) catheter. In a previously treated patient, two customized baseline plans were generated using multiple channels of the Contura(®) catheter prescribed to the Planning Target Volume Evaluation (PTV_Eval). Symmetric expansions of 1.0 mm (0-9 mm) increments around the balloon surface were performed to simulate a "Virtual Seroma" (VS) accumulation for both balloon volumes and plans were obtained for each expansion using Eclipse Brachyvision™. An analysis of these plans was then performed to evaluate the effect of seroma accumulation on dosimetric parameters of V100 and V90. 20 plans were generated and analyzed (10 plans for each balloon volume), representing VS of 6.0-66.0 cc. There was a commensurate decrease in the dose delivered to the PTV_Eval V100 and V90 (as defined by the original treatment plan) with increasing VS accumulation leading to a sub-optimal coverage of the PTV_Eval. For 30 cc MLB catheter, V100 decreased by 1.4% and V90 decreased by 0.9% for every 1 cc of VS. For 45cc MLB catheter, V100 decreased by 1.3% and V90 decreased by 1.15% for every 1.0 cc accumulation of VS. Balloon catheter-tissue adherence ensures daily dose delivery to the planned PTV_Eval. Accumulation of seroma, hematoma or air between HDR fractions can significantly impact PTV_Eval dosimetry. Vacuum-port aspiration prior to delivery of each fraction, if available, should be considered to minimize the risk of geographic under dosing.

  6. Comparison of TG-43 and TG-186 in breast irradiation using a low energy electronic brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    White, Shane A.; Landry, Guillaume; Reniers, Brigitte, E-mail: brigitte.reniers@maastro.nl [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN (Netherlands); Fonseca, Gabriel Paiva [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN, The Netherlands and Instituto de Pesquisas Energéticas e Nucleares – IPEN-CNEN/SP, São Paulo CP 11049, 05422-970 (Brazil); Holt, Randy; Rusch, Thomas [Xoft, A Subsidiary of iCAD, Sunnyvale, California 94085-4115 (United States); Beaulieu, Luc [Centre Hospitalier Universitaire de Québec Université Laval, Radio-Oncologie et Centre de Recherche en Cancérologie de l’Université Laval, Québec, Québec G1R 2J6 Canada (Canada); Verhaegen, Frank [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center (MUMC), Maastricht 6201 BN, The Netherlands and Department of Oncology, McGill University, Montreal, Quebec H3G 1A4 (Canada)

    2014-06-15

    Purpose: The recently updated guidelines for dosimetry in brachytherapy in TG-186 have recommended the use of model-based dosimetry calculations as a replacement for TG-43. TG-186 highlights shortcomings in the water-based approach in TG-43, particularly for low energy brachytherapy sources. The Xoft Axxent is a low energy (<50 kV) brachytherapy system used in accelerated partial breast irradiation (APBI). Breast tissue is a heterogeneous tissue in terms of density and composition. Dosimetric calculations of seven APBI patients treated with Axxent were made using a model-based Monte Carlo platform for a number of tissue models and dose reporting methods and compared to TG-43 based plans. Methods: A model of the Axxent source, the S700, was created and validated against experimental data. CT scans of the patients were used to create realistic multi-tissue/heterogeneous models with breast tissue segmented using a published technique. Alternative water models were used to isolate the influence of tissue heterogeneity and backscatter on the dose distribution. Dose calculations were performed using Geant4 according to the original treatment parameters. The effect of the Axxent balloon applicator used in APBI which could not be modeled in the CT-based model, was modeled using a novel technique that utilizes CAD-based geometries. These techniques were validated experimentally. Results were calculated using two dose reporting methods, dose to water (D{sub w,m}) and dose to medium (D{sub m,m}), for the heterogeneous simulations. All results were compared against TG-43-based dose distributions and evaluated using dose ratio maps and DVH metrics. Changes in skin and PTV dose were highlighted. Results: All simulated heterogeneous models showed a reduced dose to the DVH metrics that is dependent on the method of dose reporting and patient geometry. Based on a prescription dose of 34 Gy, the average D{sub 90} to PTV was reduced by between ∼4% and ∼40%, depending on the

  7. Comparison of TG-43 and TG-186 in breast irradiation using a low energy electronic brachytherapy source.

    Science.gov (United States)

    White, Shane A; Landry, Guillaume; Fonseca, Gabriel Paiva; Holt, Randy; Rusch, Thomas; Beaulieu, Luc; Verhaegen, Frank; Reniers, Brigitte

    2014-06-01

    The recently updated guidelines for dosimetry in brachytherapy in TG-186 have recommended the use of model-based dosimetry calculations as a replacement for TG-43. TG-186 highlights shortcomings in the water-based approach in TG-43, particularly for low energy brachytherapy sources. The Xoft Axxent is a low energy (brachytherapy system used in accelerated partial breast irradiation (APBI). Breast tissue is a heterogeneous tissue in terms of density and composition. Dosimetric calculations of seven APBI patients treated with Axxent were made using a model-based Monte Carlo platform for a number of tissue models and dose reporting methods and compared to TG-43 based plans. A model of the Axxent source, the S700, was created and validated against experimental data. CT scans of the patients were used to create realistic multi-tissue/heterogeneous models with breast tissue segmented using a published technique. Alternative water models were used to isolate the influence of tissue heterogeneity and backscatter on the dose distribution. Dose calculations were performed using Geant4 according to the original treatment parameters. The effect of the Axxent balloon applicator used in APBI which could not be modeled in the CT-based model, was modeled using a novel technique that utilizes CAD-based geometries. These techniques were validated experimentally. Results were calculated using two dose reporting methods, dose to water (Dw,m) and dose to medium (Dm,m), for the heterogeneous simulations. All results were compared against TG-43-based dose distributions and evaluated using dose ratio maps and DVH metrics. Changes in skin and PTV dose were highlighted. All simulated heterogeneous models showed a reduced dose to the DVH metrics that is dependent on the method of dose reporting and patient geometry. Based on a prescription dose of 34 Gy, the average D90 to PTV was reduced by between ~4% and ~40%, depending on the scoring method, compared to the TG-43 result. Peak skin dose

  8. A Prospective Longitudinal Clinical Trial Evaluating Quality of Life After Breast-Conserving Surgery and High-Dose-Rate Interstitial Brachytherapy for Early-Stage Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Garsa, Adam A.; Ferraro, Daniel J.; DeWees, Todd A. [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Deshields, Teresa L. [Department of Medicine, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Margenthaler, Julie A.; Cyr, Amy E. [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Naughton, Michael [Department of Medicine, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Aft, Rebecca [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Department of Surgery, John Cochran Veterans Hospital, St. Louis, Missouri (United States); Gillanders, William E.; Eberlein, Timothy [Department of Surgery, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Matesa, Melissa A.; Ochoa, Laura L. [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States); Zoberi, Imran, E-mail: izoberi@radonc.wustl.edu [Department of Radiation Oncology, Siteman Cancer Center, Barnes-Jewish Hospital and Washington University School of Medicine, St. Louis, Missouri (United States)

    2013-12-01

    Purpose: To prospectively examine quality of life (QOL) of patients with early stage breast cancer treated with accelerated partial breast irradiation (APBI) using high-dose-rate (HDR) interstitial brachytherapy. Methods and Materials: Between March 2004 and December 2008, 151 patients with early stage breast cancer were enrolled in a phase 2 prospective clinical trial. Eligible patients included those with Tis-T2 tumors measuring ≤3 cm excised with negative surgical margins and with no nodal involvement. Patients received 3.4 Gy twice daily to a total dose of 34 Gy. QOL was measured using European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30, version 3.0, and QLQ-BR23 questionnaires. The QLQ-C30 and QLQ-BR23 questionnaires were evaluated during pretreatment and then at 6 to 8 weeks, 3 to 4 months, 6 to 8 months, and 1 and 2 years after treatment. Results: The median follow-up was 55 months. Breast symptom scores remained stable in the months after treatment, and they significantly improved 6 to 8 months after treatment. Scores for emotional functioning, social functioning, and future perspective showed significant improvement 2 years after treatment. Symptomatic fat necrosis was associated with several changes in QOL, including increased pain, breast symptoms, systemic treatment side effects, dyspnea, and fatigue, as well as decreased role functioning, emotional functioning, and social functioning. Conclusions: HDR multicatheter interstitial brachytherapy was well tolerated, with no significant detrimental effect on measured QOL scales/items through 2 years of follow-up. Compared to pretreatment scores, there was improvement in breast symptoms, emotional functioning, social functioning, and future perspective 2 years after treatment.

  9. Treatment planning for multicatheter interstitial brachytherapy of breast cancer - from Paris system to anatomy-based inverse planning.

    Science.gov (United States)

    Major, Tibor; Polgár, Csaba

    2017-02-01

    In the last decades, treatment planning for multicatheter interstitial breast brachytherapy has evolved considerably from fluoroscopy-based 2D to anatomy-based 3D planning. To plan the right positions of the catheters, ultrasound or computed tomography (CT) imaging can be used, but the treatment plan is always based on postimplant CT images. With CT imaging, the 3D target volume can be defined more precisely and delineation of the organs at risk volumes is also possible. Consequently, parameters calculated from dose-volume histogram can be used for quantitative plan evaluation. The catheter reconstruction is also easier and faster on CT images compared to X-ray films. In high dose rate brachytherapy, using a stepping source, a number of forward dose optimization methods (manual, geometrical, on dose points, graphical) are available to shape the dose distribution to the target volume, and these influence dose homogeneities to different extent. Currently, inverse optimization algorithms offer new possibilities to improve dose distributions further considering the requirements for dose coverage, dose homogeneity, and dose to organs at risk simultaneously and automatically. In this article, the evolvement of treatment planning for interstitial breast implants is reviewed, different forward optimization methods are discussed, and dose-volume parameters used for quantitative plan evaluation are described. Finally, some questions of the inverse optimization method are investigated and initial experiences of the authors are presented.

  10. Treatment planning for multicatheter interstitial brachytherapy of breast cancer – from Paris system to anatomy-based inverse planning

    Directory of Open Access Journals (Sweden)

    Tibor Major

    2017-02-01

    Full Text Available In the last decades, treatment planning for multicatheter interstitial breast brachytherapy has evolved considerably from fluoroscopy-based 2D to anatomy-based 3D planning. To plan the right positions of the catheters, ultrasound or computed tomography (CT imaging can be used, but the treatment plan is always based on postimplant CT images. With CT imaging, the 3D target volume can be defined more precisely and delineation of the organs at risk volumes is also possible. Consequently, parameters calculated from dose-volume histogram can be used for quantitative plan evaluation. The catheter reconstruction is also easier and faster on CT images compared to X-ray films. In high dose rate brachytherapy, using a stepping source, a number of forward dose optimization methods (manual, geometrical, on dose points, graphical are available to shape the dose distribution to the target volume, and these influence dose homogeneities to different extent. Currently, inverse optimization algorithms offer new possibilities to improve dose distributions further considering the requirements for dose coverage, dose homogeneity, and dose to organs at risk simultaneously and automatically. In this article, the evolvement of treatment planning for interstitial breast implants is reviewed, different forward optimization methods are discussed, and dose-volume parameters used for quantitative plan evaluation are described. Finally, some questions of the inverse optimization method are investigated and initial experiences of the authors are presented.

  11. A comparison of the relative biological effectiveness of low energy electronic brachytherapy sources in breast tissue: a Monte Carlo study.

    Science.gov (United States)

    White, Shane A; Reniers, Brigitte; de Jong, Evelyn E C; Rusch, Thomas; Verhaegen, Frank

    2016-01-07

    Electronic brachytherapy sources use low energy photons to treat the tumor bed during or after breast-conserving surgery. The relative biological effectiveness of two electronic brachytherapy sources was explored to determine if spectral differences due to source design influenced radiation quality and if radiation quality decreased with distance in the breast. The RBE was calculated through the number of DNA double strand breaks (RBEDSB) using the Monte Carlo damage simulator (MCDS) in combination with other Monte Carlo electron/photon spectrum calculations. 50kVp photons from the Intrabeam (Carl Zeiss Surgical) and Axxent (Xoft) through 40-mm spherical applicators were simulated to account for applicator and tissue attenuation in a variety of breast tissue compositions. 40kVp Axxent photons were also simulated. Secondary electrons (known to be responsible for most DNA damage) spectra at different distance were inputted into MCDS to calculate the RBEDSB. All RBEDSB used a cobalt-60 reference. RBEDSB data was combined with corresponding average photon spectrum energy for the Axxent and applied to model-based average photon energy distributions to produce an RBEDSB map of an accelerated partial breast irradiation (APBI) patient. Both Axxent and Intrabeam 50kVp spectra were shown to have a comparable RBEDSB of between 1.4 and 1.6 at all distances in spite of progressive beam hardening. The Axxent 40kVp also demonstrated a similar RBEDSB at distances. Most RBEDSB variability was dependent on the tissue type as was seen in rib (RBEDSB  ≈  1.4), gland (≈1.55), adipose (≈1.59), skin (≈1.52) and lung (≈1.50). RBEDSB variability between both sources was within 2%. A correlation was shown between RBEDSB and average photon energy and used to produce an RBEDSB map of a dose distribution in an APBI patient dataset. Radiation quality is very similar between electronic brachytherapy sources studied. No significant reductions in RBEDSB were observed with

  12. A comparison of the relative biological effectiveness of low energy electronic brachytherapy sources in breast tissue: a Monte Carlo study

    Science.gov (United States)

    White, Shane A.; Reniers, Brigitte; de Jong, Evelyn E. C.; Rusch, Thomas; Verhaegen, Frank

    2016-01-01

    Electronic brachytherapy sources use low energy photons to treat the tumor bed during or after breast-conserving surgery. The relative biological effectiveness of two electronic brachytherapy sources was explored to determine if spectral differences due to source design influenced radiation quality and if radiation quality decreased with distance in the breast. The RBE was calculated through the number of DNA double strand breaks (RBEDSB) using the Monte Carlo damage simulator (MCDS) in combination with other Monte Carlo electron/photon spectrum calculations. 50kVp photons from the Intrabeam (Carl Zeiss Surgical) and Axxent (Xoft) through 40-mm spherical applicators were simulated to account for applicator and tissue attenuation in a variety of breast tissue compositions. 40kVp Axxent photons were also simulated. Secondary electrons (known to be responsible for most DNA damage) spectra at different distance were inputted into MCDS to calculate the RBEDSB. All RBEDSB used a cobalt-60 reference. RBEDSB data was combined with corresponding average photon spectrum energy for the Axxent and applied to model-based average photon energy distributions to produce an RBEDSB map of an accelerated partial breast irradiation (APBI) patient. Both Axxent and Intrabeam 50kVp spectra were shown to have a comparable RBEDSB of between 1.4 and 1.6 at all distances in spite of progressive beam hardening. The Axxent 40kVp also demonstrated a similar RBEDSB at distances. Most RBEDSB variability was dependent on the tissue type as was seen in rib (RBEDSB  ≈  1.4), gland (≈1.55), adipose (≈1.59), skin (≈1.52) and lung (≈1.50). RBEDSB variability between both sources was within 2%. A correlation was shown between RBEDSB and average photon energy and used to produce an RBEDSB map of a dose distribution in an APBI patient dataset. Radiation quality is very similar between electronic brachytherapy sources studied. No significant reductions in RBEDSB were observed with

  13. Impact of interfraction seroma collection on breast brachytherapy dosimetry – a mathematical model

    Science.gov (United States)

    Sowards, Keith; Bhatt, Geetika; Freeman, Andrew; Dragun, Anthony

    2012-01-01

    Purpose Balloon brachytherapy is a widely accepted modality for delivery of accelerated partial breast irradiation (APBI). Our hypothesis was that inter-fraction seroma collection around the balloon surface would have an adverse effect on dosimetry of the target. Material and methods This is a dosimetric re-planning study using two volumetric models (30 cc and 45 cc) in a Contura® multi-lumen balloon (MLB) catheter. In a previously treated patient, two customized baseline plans were generated using multiple channels of the Contura® catheter prescribed to the Planning Target Volume Evaluation (PTV_Eval). Symmetric expansions of 1.0 mm (0-9 mm) increments around the balloon surface were performed to simulate a “Virtual Seroma” (VS) accumulation for both balloon volumes and plans were obtained for each expansion using Eclipse Brachyvision™. An analysis of these plans was then performed to evaluate the effect of seroma accumulation on dosimetric parameters of V100 and V90. Results 20 plans were generated and analyzed (10 plans for each balloon volume), representing VS of 6.0-66.0 cc. There was a commensurate decrease in the dose delivered to the PTV_Eval V100 and V90 (as defined by the original treatment plan) with increasing VS accumulation leading to a sub-optimal coverage of the PTV_Eval. For 30 cc MLB catheter, V100 decreased by 1.4% and V90 decreased by 0.9% for every 1 cc of VS. For 45cc MLB catheter, V100 decreased by 1.3% and V90 decreased by 1.15% for every 1.0 cc accumulation of VS. Conclusions Balloon catheter-tissue adherence ensures daily dose delivery to the planned PTV_Eval. Accumulation of seroma, hematoma or air between HDR fractions can significantly impact PTV_Eval dosimetry. Vacuum-port aspiration prior to delivery of each fraction, if available, should be considered to minimize the risk of geographic under dosing. PMID:23349651

  14. Modeling study for optimization of skin dose for partial breast irradiation using Xoft Axxent electronic brachytherapy applicator.

    Science.gov (United States)

    Hepel, Jaroslaw T; Hiatt, Jessica R; Cardarelli, Gene A; Wazer, David E

    2010-01-01

    Balloon brachytherapy with the MammoSite system (Hologic Inc., Bedford, MA) is a widely used approach for accelerated partial breast irradiation. Inherent to this approach, high skin doses can occur if the balloon to skin distance is small. This has been associated with late skin toxicity, particularly telangiectasia. The Xoft Axxent electronic brachytherapy balloon applicator (Xoft, Fremont, CA) is a novel device for accelerated partial breast irradiation. It is unique in that it uses an electronic 50-kV source. This source has a pronounced anisotropy with constriction of isodose distribution at the proximal end of the catheter. This anisotropy can be considered as an advantage to optimize skin dose when the cavity to skin distance is small. In this study, we simulated various balloon-insertion orientations to optimized skin surface dose. Breast phantoms were constructed of tissue-equivalent material. Xoft Axxent balloon catheters were inserted at a distance of 6mm from the surface. The catheter was placed at three different catheter to surface orientations: (1) perpendicular to the surface, (2) oblique to the surface (45 degrees), and (3) parallel to the surface. Three-dimensional treatment planning was then performed using Nucletron's Plato planning system (Nucletron, Columbia, MD). Multiple dwell positions were used, and the dose was optimized to the target volume. The target volume was defined as volume from the balloon surface to 1-cm distance from the balloon surface or to the phantom surface (if less then 1cm from the balloon surface). Target volume coverage was compared between plans using dose-volume histograms. Surface doses were compared using isodose line distribution and surface point doses. Plato planned surface doses were then verified by direct measurement using Landauer Dot InLight dosimeters (Landauer, Glenwood, IL). Excellent target coverage was obtained for all three catheter orientations with a D(95) of > or =95%. Surface dose was lowest for

  15. Dose volume histogram analysis of normal structures associated with accelerated partial breast irradiation delivered by high dose rate brachytherapy and comparison with whole breast external beam radiotherapy fields.

    Science.gov (United States)

    Stewart, Alexandra J; O'Farrell, Desmond A; Cormack, Robert A; Hansen, Jorgen L; Khan, Atif J; Mutyala, Subhakar; Devlin, Phillip M

    2008-11-19

    To assess the radiation dose delivered to the heart and ipsilateral lung during accelerated partial breast brachytherapy using a MammoSite applicator and compare to those produced by whole breast external beam radiotherapy (WBRT). Dosimetric analysis was conducted on patients receiving MammoSite breast brachytherapy following conservative surgery for invasive ductal carcinoma. Cardiac dose was evaluated for patients with left breast tumors with a CT scan encompassing the entire heart. Lung dose was evaluated for patients in whom the entire lung was scanned. The prescription dose of 3400 cGy was 1 cm from the balloon surface. MammoSite dosimetry was compared to simulated WBRT fields with and without radiobiological correction for the effects of dose and fractionation. Dose parameters such as the volume of the structure receiving 10 Gy or more (V10) and the dose received by 20 cc of the structure (D20), were calculated as well as the maximum and mean doses received. Fifteen patients were studied, five had complete lung data and six had left-sided tumors with complete cardiac data. Ipsilateral lung volumes ranged from 925-1380 cc. Cardiac volumes ranged from 337-551 cc. MammoSite resulted in a significantly lower percentage lung V30 and lung and cardiac V20 than the WBRT fields, with and without radiobiological correction. This study gives low values for incidental radiation received by the heart and ipsilateral lung using the MammoSite applicator. The volume of heart and lung irradiated to clinically significant levels was significantly lower with the MammoSite applicator than using simulated WBRT fields of the same CT data sets.

  16. Dose volume histogram analysis of normal structures associated with accelerated partial breast irradiation delivered by high dose rate brachytherapy and comparison with whole breast external beam radiotherapy fields

    Directory of Open Access Journals (Sweden)

    Mutyala Subhakar

    2008-11-01

    Full Text Available Abstract Purpose To assess the radiation dose delivered to the heart and ipsilateral lung during accelerated partial breast brachytherapy using a MammoSite™ applicator and compare to those produced by whole breast external beam radiotherapy (WBRT. Materials and methods Dosimetric analysis was conducted on patients receiving MammoSite breast brachytherapy following conservative surgery for invasive ductal carcinoma. Cardiac dose was evaluated for patients with left breast tumors with a CT scan encompassing the entire heart. Lung dose was evaluated for patients in whom the entire lung was scanned. The prescription dose of 3400 cGy was 1 cm from the balloon surface. MammoSite dosimetry was compared to simulated WBRT fields with and without radiobiological correction for the effects of dose and fractionation. Dose parameters such as the volume of the structure receiving 10 Gy or more (V10 and the dose received by 20 cc of the structure (D20, were calculated as well as the maximum and mean doses received. Results Fifteen patients were studied, five had complete lung data and six had left-sided tumors with complete cardiac data. Ipsilateral lung volumes ranged from 925–1380 cc. Cardiac volumes ranged from 337–551 cc. MammoSite resulted in a significantly lower percentage lung V30 and lung and cardiac V20 than the WBRT fields, with and without radiobiological correction. Conclusion This study gives low values for incidental radiation received by the heart and ipsilateral lung using the MammoSite applicator. The volume of heart and lung irradiated to clinically significant levels was significantly lower with the MammoSite applicator than using simulated WBRT fields of the same CT data sets. Trial registration Dana Farber Trial Registry number 03-179

  17. A Multi-Institutional Study of Feasibility, Implementation, and Early Clinical Results With Noninvasive Breast Brachytherapy for Tumor Bed Boost

    Energy Technology Data Exchange (ETDEWEB)

    Hamid, Subarna, E-mail: shamid@tuftsmedicalcenter.org [Department of Radiation Oncology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA (United States); Department of Radiation Oncology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI (United States); Rocchio, Kathy [Department of Radiation Oncology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI (United States); Arthur, Douglas; Vera, Robyn [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, VA (United States); Sha, Sandra; Jolly, Michele [Central Florida Cancer Institute, Davenport, FL (United States); Cavanaugh, Sean; Wooten, Eric [Atlanta Oncology Associates, Hawkinsville, GA (United States); Benda, Rashmi; Greenfield, Brad [Department of Radiation Oncology, Boca Raton Community Hospital, Boca Raton, FL (United States); Prestidge, Bradley [Texas Cancer Clinic, San Antonio, TX (United States); Ackerman, Scot [First Coast Oncology, Jacksonville, FL (United States); Kuske, Robert; Quiet, Coral; Snyder, Margaret [Arizona Breast Cancer Specialists, Phoenix, AZ (United States); Wazer, David E. [Department of Radiation Oncology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA (United States); Department of Radiation Oncology, Rhode Island Hospital, Alpert Medical School of Brown University, Providence, RI (United States)

    2012-08-01

    Purpose: To evaluate the feasibility, implementation, and early results of noninvasive breast brachytherapy (NIBB) for tumor bed boost with whole breast radiation therapy (WBRT). Methods and Materials: NIBB is a commercially available (AccuBoost, Billerica, MA) mammography-based, brachytherapy system in which the treatment applicators are centered on the planning target volume (PTV) to direct {sup 192}Ir emissions along orthogonal axes. A privacy-encrypted online data registry collected information from 8 independent academic and community-based institutions. Data were from 146 consecutive women with early-stage breast cancer after lumpectomy and WBRT receiving boost with NIBB between July 2007 and March 2010. Toxicity and cosmesis were graded according to the Common Toxicity Criteria (v. 3.0) and the Harvard scale. Median follow-up was 6 months (1-39 months). Results: Grade 1-2 skin toxicity was observed in 64%, 48%, and 21% during the acute (1-3 weeks), intermediate (4-26 weeks), and late-intermediate (>26 weeks) periods. There was no Grade 4 toxicity. At 6 months, for the entire cohort, cosmesis was excellent/good in 62%/38%. The subset receiving NIBB before WBRT had cosmetic scores of 32% and 63%, whereas during WBRT, 58% and 37% were rated as excellent and good, respectively. Breast compression was scored as 'uncomfortable' in 12%, 29%, and 59% when NIBB was delivered before, during, or after WBRT. For each patient, the fraction-to-fraction variability in PTV was low. Skin flash was associated with a higher proportion of excellent cosmesis (58% vs. 42%) relative to having the applicator all within breast tissue. Conclusions: These data indicate that NIBB is feasible and can be consistently implemented in a broad array of practice settings. Preliminary evaluation suggests that NIBB is associated with acceptably mild normal tissue toxicity and favorable early cosmesis. The application of NIBB before WBRT may be associated with better patient tolerance

  18. Impact of heterogeneity-corrected dose calculation using a grid-based Boltzmann solver on breast and cervix cancer brachytherapy

    Directory of Open Access Journals (Sweden)

    Julia Hofbauer

    2016-04-01

    Full Text Available Purpose : To analyze the impact of heterogeneity-corrected dose calculation on dosimetric quality parameters in gyne¬cological and breast brachytherapy using Acuros, a grid-based Boltzmann equation solver (GBBS, and to evaluate the shielding effects of different cervix brachytherapy applicators. Material and methods: Calculations with TG-43 and Acuros were based on computed tomography (CT retrospectively, for 10 cases of accelerated partial breast irradiation and 9 cervix cancer cases treated with tandem-ring applicators. Phantom CT-scans of different applicators (plastic and titanium were acquired. For breast cases the Vbreast, a decrease of ~8% was found for D 10cm³ to the skin and 5% for D 2cm³ to rib, resulting in a difference ~ –1.5 Gy EQD2 for overall treatment. Smaller effects were found for cervix cases with the plastic applicator, with up to –2% (–0.2 Gy EQD2 per fraction for organs at risk and –0.5% (–0.3 Gy EQD2 per fraction for CTV HR . The shielding effect of the titanium applicator resulted in a decrease of 2% for D 2cm³ to the organ at risk versus 0.7% for plastic. Conclusions : Lower doses were reported when calculating with Acuros compared to TG-43. Differences in dose parameters were larger in breast cases. A lower impact on clinical dose parameters was found for the cervix cases. Applicator material causes

  19. Impact of heterogeneity-corrected dose calculation using a grid-based Boltzmann solver on breast and cervix cancer brachytherapy.

    Science.gov (United States)

    Hofbauer, Julia; Kirisits, Christian; Resch, Alexandra; Xu, Yingjie; Sturdza, Alina; Pötter, Richard; Nesvacil, Nicole

    2016-04-01

    To analyze the impact of heterogeneity-corrected dose calculation on dosimetric quality parameters in gynecological and breast brachytherapy using Acuros, a grid-based Boltzmann equation solver (GBBS), and to evaluate the shielding effects of different cervix brachytherapy applicators. Calculations with TG-43 and Acuros were based on computed tomography (CT) retrospectively, for 10 cases of accelerated partial breast irradiation and 9 cervix cancer cases treated with tandem-ring applicators. Phantom CT-scans of different applicators (plastic and titanium) were acquired. For breast cases the V20Gyαβ3 to lung, the D0.1cm(3) , D1cm(3) , D2cm(3) to rib, the D0.1cm(3) , D1cm(3) , D10cm(3) to skin, and Dmax for all structures were reported. For cervix cases, the D0.1cm(3) , D2cm(3) to bladder, rectum and sigmoid, and the D50, D90, D98, V100 for the CTVHR were reported. For the phantom study, surrogates for target and organ at risk were created for a similar dose volume histogram (DVH) analysis. Absorbed dose and equivalent dose to 2 Gy fractionation (EQD2) were used for comparison. Calculations with TG-43 overestimated the dose for all dosimetric indices investigated. For breast, a decrease of ~8% was found for D10cm(3) to the skin and 5% for D2cm(3) to rib, resulting in a difference ~ -1.5 Gy EQD2 for overall treatment. Smaller effects were found for cervix cases with the plastic applicator, with up to -2% (-0.2 Gy EQD2) per fraction for organs at risk and -0.5% (-0.3 Gy EQD2) per fraction for CTVHR. The shielding effect of the titanium applicator resulted in a decrease of 2% for D2cm(3) to the organ at risk versus 0.7% for plastic. Lower doses were reported when calculating with Acuros compared to TG-43. Differences in dose parameters were larger in breast cases. A lower impact on clinical dose parameters was found for the cervix cases. Applicator material causes systematic shielding effects that can be taken into account.

  20. Re-irradiation of the chest wall for local breast cancer recurrence. Results of salvage brachytherapy with hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    Auoragh, A. [University Hospital Erlangen, Department of Radiation Oncology, Erlangen (Germany); Hospital Fuerth, Department of Radiation Oncology, Fuerth (Germany); Strnad, V.; Ott, O.J.; Fietkau, R. [University Hospital Erlangen, Department of Radiation Oncology, Erlangen (Germany); Beckmann, M.W. [University Hospital Erlangen, Department of Gynecology and Obstetrics, Erlangen (Germany)

    2016-09-15

    Following mastectomy and adjuvant external beam radiation therapy in patients with breast cancer, the incidence of local or locoregional recurrence is approximately 9 % (2-20 %). Alongside the often limited possibilities of surgical treatment, radiation therapy combined with superficial hyperthermia is the most effective local therapy. In the present work, a retrospective analysis of salvage brachytherapy combined with superficial hyperthermia for chest wall recurrences is presented. Between 2004 and 2011, 18 patients with a total of 23 target volumes resulting from chest wall recurrences after previously mastectomy and external beam radiation therapy (median 56 Gy, range 50-68 Gy) were treated with superficial brachytherapy as salvage treatment: 8 patients (44 %) had macroscopic tumor, 3 (17 %) had microscopic tumor (R1), and 7 (39 %) had undergone R0 resection and were treated due to risk factors. A dose of 50 Gy was given (high-dose rate [HDR] and pulsed-dose rate [PDR] procedures). In all, 5 of 23 patients (22 %) received additional concurrent chemotherapy, and in 20 of 23 (87 %) target volumes additional superficial hyperthermia was carried out twice weekly. The 5-year local recurrence-free survival was 56 %, the disease-free survival was 28 %, and a 5-year overall survival was 22 %. Late side effects Common Toxicity Criteria (CTC) grade 3 were reported in 17 % of the patients: 2 of 18 (11 %) had CTC grade 3 fibrosis, and 1 of 18 (6 %) had a chronic wound healing disorder. Re-irradiation as salvage brachytherapy with superficial hyperthermia for chest wall recurrences is a feasible and safe treatment with good local control results and acceptable late side effects. (orig.) [German] Nach einer Mastektomie und adjuvanter Strahlentherapie bei Patientinnen mit Mammakarzinom kommt es bei 9 % (2-20 %) zum lokalen bzw. lokoregionaeren Rezidiv. Neben den oft limitierten operativen Behandlungsmoeglichkeiten ist die Strahlentherapie mit Oberflaechenhyperthermie die

  1. Five-year results: the initial clinical trial of MammoSite balloon brachytherapy for partial breast irradiation in early-stage breast cancer.

    Science.gov (United States)

    Benitez, Pamela R; Keisch, Martin E; Vicini, Frank; Stolier, Alan; Scroggins, Troy; Walker, Alonzo; White, Julia; Hedberg, Peter; Hebert, Mary; Arthur, Doug; Zannis, Vic; Quiet, Coral; Streeter, Oscar; Silverstein, Mel

    2007-10-01

    Patients with early-stage invasive ductal breast cancer were prospectively evaluated using MammoSite RTS balloon brachytherapy (RTS Cytyc Corp, Marlborough, MA) as the sole modality for delivering accelerated partial breast irradiation to the lumpectomy bed with breast-conserving surgery. This report presents the 5-year results of the treated patients. From May 2000 to October 2001, 70 patients were enrolled in this prospective study. Forty-three patients completed accelerated partial breast irradiation with MammoSite brachytherapy following lumpectomy and axillary staging. Thirty-six patients have been followed for a median of 5.5 years (mean 65.2 months). Criteria for entry into the study were unifocal invasive ductal carcinoma, tumor size or = 45 years, absence of extensive intraductal component, cavity size > or = 3 cm in 1 dimension, node-negative, and final margins negative per National Surgical Adjuvant Breast and Bowel Project definition. A minimum balloon-to-skin surface distance of 5 mm was required. A dose of 34 Gy was delivered in 10 fractions over 5 days prescribed to 1 cm from the applicator surface using iridium-192 high-dose-rate brachytherapy. Data on infection, seromas, cosmetic outcome, and toxicities were collected at 3 and 6 months and at yearly intervals. Local recurrences, both true recurrences in the lumpectomy bed and failures outside the initially treated target volume (elsewhere failures), were recorded. Contralateral breast failure rates were noted. The catheter was not implanted in 16 of the 70 enrolled patients due to cavity size not amenable to balloon placement (n = 10), ineligible by criteria (n = 4), and skin spacing (n = 2). Fifty-four patients were implanted and 43 were successfully treated with MammoSite balloon brachytherapy. Reasons for catheter explantation in 11 patients were poor cavity conformance in 7, inadequate skin spacing in 2, positive node in 1 and age less than 45 years in 1. Of the 43 patients who completed

  2. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    Energy Technology Data Exchange (ETDEWEB)

    Shi Chengyu; Guo Bingqi; Eng, Tony; Papanikolaou, Nikos [Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, TX 78229 (United States); Cheng, Chih-Yao, E-mail: shic@uthscsa.ed [Radiation Oncology Department, Oklahoma University Health Science Center, Oklahoma, OK 73104 (United States)

    2010-09-21

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent(TM) x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V{sub 100} reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as

  3. Applications of tissue heterogeneity corrections and biologically effective dose volume histograms in assessing the doses for accelerated partial breast irradiation using an electronic brachytherapy source

    Science.gov (United States)

    Shi, Chengyu; Guo, Bingqi; Cheng, Chih-Yao; Eng, Tony; Papanikolaou, Nikos

    2010-09-01

    A low-energy electronic brachytherapy source (EBS), the model S700 Axxent™ x-ray device developed by Xoft Inc., has been used in high dose rate (HDR) intracavitary accelerated partial breast irradiation (APBI) as an alternative to an Ir-192 source. The prescription dose and delivery schema of the electronic brachytherapy APBI plan are the same as the Ir-192 plan. However, due to its lower mean energy than the Ir-192 source, an EBS plan has dosimetric and biological features different from an Ir-192 source plan. Current brachytherapy treatment planning methods may have large errors in treatment outcome prediction for an EBS plan. Two main factors contribute to the errors: the dosimetric influence of tissue heterogeneities and the enhancement of relative biological effectiveness (RBE) of electronic brachytherapy. This study quantified the effects of these two factors and revisited the plan quality of electronic brachytherapy APBI. The influence of tissue heterogeneities is studied by a Monte Carlo method and heterogeneous 'virtual patient' phantoms created from CT images and structure contours; the effect of RBE enhancement in the treatment outcome was estimated by biologically effective dose (BED) distribution. Ten electronic brachytherapy APBI cases were studied. The results showed that, for electronic brachytherapy cases, tissue heterogeneities and patient boundary effect decreased dose to the target and skin but increased dose to the bones. On average, the target dose coverage PTV V100 reduced from 95.0% in water phantoms (planned) to only 66.7% in virtual patient phantoms (actual). The actual maximum dose to the ribs is 3.3 times higher than the planned dose; the actual mean dose to the ipsilateral breast and maximum dose to the skin were reduced by 22% and 17%, respectively. Combining the effect of tissue heterogeneities and RBE enhancement, BED coverage of the target was 89.9% in virtual patient phantoms with RBE enhancement (actual BED) as compared to 95

  4. Recommendations from GEC ESTRO Breast Cancer Working Group (II): Target definition and target delineation for accelerated or boost partial breast irradiation using multicatheter interstitial brachytherapy after breast conserving open cavity surgery.

    Science.gov (United States)

    Major, Tibor; Gutiérrez, Cristina; Guix, Benjamin; van Limbergen, Erik; Strnad, Vratislav; Polgár, Csaba

    2016-01-01

    To prepare guidelines for target definition and delineations after open cavity breast conserving surgery in accelerated partial breast irradiations or boost treatments using multicatheter interstitial brachytherapy based on the consensus of the Breast Working Group of GEC-ESTRO. Following a study on interobserver variations of target volume delineation in multicatheter breast brachytherapy after open cavity surgery and a number of discussions in consensus meetings these guidelines were worked out by experts on the field. (1) Consistent windowing has to be used for proper cavity visualization. (2) The cavity visualization score has to be at least 3 in order to minimize the interobserver variations of target definition. (3) At delineation of surgical cavity only the homogeneous part of the postoperative seroma has to be included in the contours and protrusions or sharp irregularities have to be excluded. When surgical clips are present, they have to be surrounded by the contour with close contact. (4) CTV is created from the outlined surgical cavity with a nonisotropic geometrical extension. In each direction the safety margin is calculated by taking into account the size of the free resection margin. The total size of safety margin is always 20mm which is the sum of the surgical and added safety margins. CTV is limited to chest wall/pectoral muscles and 5mm below the skin surface. Following these guidelines the target volume definition in breast brachytherapy after open cavity surgery is expected to be accomplished in more consistent way with low interobserver variations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  5. High-Dose-Rate Brachytherapy Boost Effect on Local Tumor Control in Young Women With Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Guinot, Jose-Luis, E-mail: jguinot@fivo.org [Department of Radiation Oncology, Fundacion Instituto Valenciano de Oncologia, Valencia (Spain); Baixauli-Perez, Cristobal [Health Services Research Unit, Center for Public Health Research, Valencia (Spain); Soler, Pablo; Tortajada, Maria Isabel; Moreno, Araceli; Santos, Miguel Angel; Mut, Alejandro [Department of Radiation Oncology, Fundacion Instituto Valenciano de Oncologia, Valencia (Spain); Gozalbo, Francisco [Department of Pathology, Fundacion Instituto Valenciano de Oncologia, Valencia (Spain); Arribas, Leoncio [Department of Radiation Oncology, Fundacion Instituto Valenciano de Oncologia, Valencia (Spain)

    2015-01-01

    Purpose: To evaluate the local control rate and complications of a single fraction of high-dose-rate brachytherapy (HDR BT) boost in women aged 45 yeas and younger after breast-conserving therapy. Methods and Materials: Between 1999 and 2007, 167 patients between the ages of 26 and 45 years old (72 were 40 years old or younger), with stages T1 to T2 invasive breast cancer with disease-free margin status of at least 5 mm after breast-conserving surgery received 46 to 50 Gy whole-breast irradiation plus a 7-Gy HDR-BT boost (“fast boost”). An axillary dissection was performed in 72.5% of the patients and sentinel lymph node biopsy in 27.5%. A supraclavicular area was irradiated in 19% of the patients. Chemotherapy was used in 86% of the patients and hormone treatment in 77%. Clinical nodes were present in 18% and pathological nodes in 29%. The pathological stage was pT0: 5%, pTis: 3%, pT1: 69% and pT2: 23%. Intraductal component was present in 40% and 28% were G3. Results: At a median follow-up of 92 months, 9 patients relapsed on the margin of the implant, and 1 patient in another quadrant, resulting in a 10-year local relapse rate of 4.3% and a breast relapse rate of 4.9%, with breast preservation in 93.4%; no case of mastectomy due to poor cosmesis arose. Actuarial 5- and 10-year disease-free, cause-specific, and overall survival rates were 87.9% and 85.8%, and 92.1% and 88.4%, and 92.1% and 87.3%, respectively. In a univariate analysis, triple-negative cases and negative hormone receptors did worse, but in a multivariate analysis, only the last factor was significant for local and breast control. Asymptomatic fibrosis G2 was recorded in 3 cases, and there were no other late complications. Cosmetic results were good to excellent in 97% of cases. Conclusions: A single dose of 7 Gy using the fast-boost technique is well tolerated, with a low rate of late complications and improved local tumor control in women aged 45 and younger, compared to published data

  6. Pulsed-dose-rate peri-operative brachytherapy as an interstitial boost in organ-sparing treatment of breast cancer

    Directory of Open Access Journals (Sweden)

    Krystyna Serkies

    2016-12-01

    Full Text Available Purpose : To evaluate peri-operative multicatheter interstitial pulsed-dose-rate brachytherapy (PDR-BT with an intra-operative catheter placement to boost the tumor excision site in breast cancer patients treated conservatively. Material and methods: Between May 2002 and October 2008, 96 consecutive T1-3N0-2M0 breast cancer patients underwent breast-conserving therapy (BCT including peri-operative PDR-BT boost, followed by whole breast external beam radiotherapy (WBRT. The BT dose of 15 Gy (1 Gy/pulse/h was given on the following day after surgery. Results: No increased bleeding or delayed wound healing related to the implants were observed. The only side effects included one case of temporary peri-operative breast infection and 3 cases of fat necrosis, both early and late. In 11 patients (11.4%, subsequent WBRT was omitted owing to the final pathology findings. These included eight patients who underwent mastectomy due to multiple adverse prognostic pathological features, one case of lobular carcinoma in situ, and two cases with no malignant tumor. With a median follow-up of 12 years (range: 7-14 years, among 85 patients who completed BCT, there was one ipsilateral breast tumor and one locoregional nodal recurrence. Six patients developed distant metastases and one was diagnosed with angiosarcoma within irradiated breast. The actuarial 5- and 10-year disease free survival was 90% (95% CI: 84-96% and 87% (95% CI: 80-94%, respectively, for the patients with invasive breast cancer, and 91% (95% CI: 84-97% and 89% (95% CI: 82-96%, respectively, for patients who completed BCT. Good cosmetic outcome by self-assessment was achieved in 58 out of 64 (91% evaluable patients. Conclusions : Peri-operative PDR-BT boost with intra-operative tube placement followed by EBRT is feasible and devoid of considerable toxicity, and provides excellent long-term local control. However, this strategy necessitates careful patient selection and histological confirmation

  7. Implementation of the technique of partial irradiation accelerated the breast with high doses (HDR) brachytherapy; Puesta en marcha de la tecnica de irradiacion parcial acelerada de la mama con braquterapia de alta tasa de dosis (HDR)

    Energy Technology Data Exchange (ETDEWEB)

    Molina Lopez, M. Y.; Pardo Perez, E.; Castro Novais, J.; Martinez Ortega, J.; Ruiz Maqueda, S.; Cerro Penalver, E. del

    2013-07-01

    The objective of this work is presents procedure carried out in our Centre for the implementation of the accelerated partial breast irradiation (APBI, accelerated partial-breast irradiation) with high-rate brachytherapy (HDR), using plastic tubes as applicators. Carried out measures, the evaluation of the dosimetric parameters analyzing and presenting the results. (Author)

  8. A comparison of skin and chest wall dose delivered with multicatheter, Contura multilumen balloon, and MammoSite breast brachytherapy.

    Science.gov (United States)

    Cuttino, Laurie W; Todor, Dorin; Rosu, Mihaela; Arthur, Douglas W

    2011-01-01

    Skin and chest wall doses have been correlated with toxicity in patients treated with breast brachytherapy . This investigation compared the ability to control skin and chest wall doses between patients treated with multicatheter (MC), Contura multilumen balloon (CMLB), and MammoSite (MS) brachytherapy. 43 patients treated with the MC technique, 45 patients treated with the CMLB, and 83 patients treated with the MS were reviewed. The maximum doses delivered to the skin and chest wall were calculated for all patients. The mean maximum skin doses for the MC, CMLB, and MS were 2.3 Gy (67% of prescription dose), 2.8 Gy (82% of prescription dose), and 3.2 Gy per fraction (94% of prescription dose), respectively. Although the skin distances were similar (p = 0.23) for the two balloon techniques, the mean skin dose with the CMLB was significantly lower than with the MS (p = 0.05). The mean maximum rib doses for the MC, CMLB, and MS were 2.3 Gy (67% of prescription dose), 2.8 Gy (82% of prescription dose), and 3.6 Gy per fraction (105% of prescription dose), respectively. Again, the mean rib dose with the CMLB was significantly lower than with the MS (p = 0.002). The MC and CMLB techniques are associated with significantly lower mean skin and rib doses than is the MS. Treatment with the MS was associated with significantly more patients receiving doses to the skin or rib in excess of 125% of the prescription. Treatment with the CMLB may prove to yield less normal tissue toxicity than treatment with the MS. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. Are the American Society for Radiation Oncology Guidelines Accurate Predictors of Recurrence in Early Stage Breast Cancer Patients Treated with Balloon-Based Brachytherapy?

    Directory of Open Access Journals (Sweden)

    Moira K. Christoudias

    2013-01-01

    Full Text Available The American Society for Radiation Oncology (ASTRO consensus statement (CS provides guidelines for patient selection for accelerated partial breast irradiation (APBI following breast conserving surgery. The purpose of this study was to evaluate recurrence rates based on ASTRO CS groupings. A single institution review of 238 early stage breast cancer patients treated with balloon-based APBI via balloon based brachytherapy demonstrated a 4-year actuarial ipsilateral breast tumor recurrence (IBTR rate of 5.1%. There were no significant differences in the 4-year actuarial IBTR rates between the “suitable,” “cautionary,” and “unsuitable” ASTRO categories (0%, 7.2%, and 4.3%, resp., P=0.28. ER negative tumors had higher rates of IBTR than ER positive tumors. The ASTRO groupings are poor predictors of patient outcomes. Further studies evaluating individual clinicopathologic features are needed to determine the safety of APBI in higher risk patients.

  10. Modelling the radiobiological effect of intraoperative X-ray brachytherapy for breast cancer using an air-filled spherical applicator

    Directory of Open Access Journals (Sweden)

    Kris Armoogum

    2016-08-01

    Full Text Available Purpose : We present a framework, in which we compare a conventional standard dose of 50 Gy in 25 fractions with accelerated partial breast irradiation (APBI using electronic brachytherapy (eBT. We discuss how radiobiological modelling enables us to establish a framework, within which we can compare external beam radiotherapy (EBRT. This leads to a determination of the shell of isoeffect in breast tissue, at which very low kV eBT can be considered to be clinically equivalent to standard EBRT. Material and methods : To estimate relative biological effectiveness (RBE values as a function of dose and irradiation time, we used a modified linear quadratic (LQ approach, taking into account the ability of this new device, to deliver 20 Gy at the surface of a 40 mm diameter rigid, hollow spherical applicator in less than 2 minutes. In this study, we considered the radiobiological effectiveness of the Papillon+™ X-ray brachytherapy device operating at 30 kV, 0.3 mA producing dose rates in excess of 14 Gy/min. Results : Calculated clinical RBEs ranged from 1.154 at the surface of a 40 mm diameter applicator to 1.100 at 35 mm from the applicator surface for the Papillon+ device. The absolute physical dose D (abs 30 kV ranged from 20.00 Gy at the applicator surface to 1.20 at 35 mm distant. The product of the isoeffective single dose of 60Co reference radiation – (RBE60Co, and the RBE corrected standard 2 Gy equivalent dose fractions (EQD2 doses, EQD2(30 kV * (RBE60Co ranged from 98.62 Gy at the applicator surface to 1.13 at 35 mm. The ‘shell of isoeffect’, the value on the X-axis where the EQD2(30 kV * (RBE60Co line crosses the 50 Gy mark on the Y-axis, was found to be approximately 3.5 mm beyond the applicator surface. Conclusions : The ‘shell of isoeffect’ can serve as a useful metric with which to compare the radiobiological effectiveness of low kV eBT with various regimes of conventional EBRT.

  11. TLD skin dose measurements and acute and late effects after lumpectomy and high-dose-rate brachytherapy only for early breast cancer.

    Science.gov (United States)

    Perera, Francisco; Chisela, Frank; Stitt, Larry; Engel, Jay; Venkatesan, Varagur

    2005-08-01

    This report examines the relationships between measured skin doses and the acute and late skin and soft tissue changes in a pilot study of lumpectomy and high-dose-rate brachytherapy only for breast cancer. Thirty-seven of 39 women enrolled in this pilot study of high-dose-rate brachytherapy (37.2 Gy in 10 fractions b.i.d.) each had thermoluminescent dosimetry (TLD) at 5 points on the skin of the breast overlying the implant volume. Skin changes at TLD dose points and fibrosis at the lumpectomy site were documented every 6 to 12 months posttreatment using a standardized physician-rated cosmesis questionnaire. The relationships between TLD dose and acute skin reaction, pigmentation, or telangiectasia at 5 years were analyzed using the GEE algorithm and the GENMOD procedure in the SAS statistical package. Fisher's exact test was used to determine whether there were any significant associations between acute skin reaction and late pigmentation or telangiectasia or between the volumes encompassed by various isodoses and fibrosis or fat necrosis. The median TLD dose per fraction (185 dose points) multiplied by 10 was 9.2 Gy. In all 37 patients, acute skin reaction Grade 1 or higher was observed at 5.9% (6 of 102) of dose points receiving 10 Gy or less vs. 44.6% (37 of 83) of dose points receiving more than 10 Gy (p skin reaction was also significantly associated with development of Grade 1 or more pigmentation or telangiectasia at 60 months. This association was most significant for acute reaction and telangiectasia directly over the lumpectomy site (p brachytherapy to the lumpectomy site, TLD skin dose was significantly related to acute skin reaction and to pigmentation and telangiectasia at 60 months. An acute skin reaction was also significantly associated with the development of telangiectasia at 60 months. TLD skin dose measurement may allow modification of the brachytherapy implant geometry (dwell times and position) to minimize late skin toxicity.

  12. Dosimetric comparison of (192)Ir high-dose-rate brachytherapy vs. 50 kV x-rays as techniques for breast intraoperative radiation therapy: conceptual development of image-guided intraoperative brachytherapy using a multilumen balloon applicator and in-room CT imaging.

    Science.gov (United States)

    Jones, Ryan; Libby, Bruce; Showalter, Shayna L; Brenin, David R; Wilson, David D; Schroen, Anneke; Morris, Monica; Reardon, Kelli A; Morrison, John; Showalter, Timothy N

    2014-01-01

    At our institution, the availability of a shielded procedure room with in-room CT-on-rails imaging allows for the exploration of a high-dose-rate (HDR) brachytherapy approach for breast intraoperative radiation therapy (IORT). We hypothesize that HDR brachytherapy will permit a higher prescription dose without increasing toxicity. In this study, we compare the dosimetry of intraoperative HDR brachytherapy, using multilumen balloon applicator, to IORT with a 50 kV source and then select a prescription dose for a subsequent clinical trial. The CT scans of 14 patients who had previously received multilumen balloon-based breast brachytherapy were replanned to a standard prescription to the target volume. The same 14 cases were planned to the specifications of a 50 kV x-ray system. Uniform volume optimization and prescription doses were used to permit direct comparisons. All plans were evaluated for the dose homogeneity index, tumor coverage, and dose to normal tissues, including skin, ribs, and heart (for left breast plans). The HDR brachytherapy plans were superior to 50 kV superficial photon plans for IORT in all dosimetric parameters except for the heart and rib dosimetric parameters. Prescription dose of 12.5 Gy to the planning target volume for evaluation yielded a dose to 95 percent of the balloon surface of 19.7 Gy. Image-guided HDR intraoperative brachytherapy with a multilumen balloon applicator provides superior target volume coverage compared with 50 kV photons, while maintaining doses within tolerance limits for normal tissues. An ongoing prospective clinical trial will evaluate the safety and feasibility of this technique. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  13. Dosimetric and radiobiological comparison of TG-43 and Monte Carlo calculations in (192)Ir breast brachytherapy applications.

    Science.gov (United States)

    Peppa, V; Pappas, E P; Karaiskos, P; Major, T; Polgár, C; Papagiannis, P

    2016-10-01

    To investigate the clinical significance of introducing model based dose calculation algorithms (MBDCAs) as an alternative to TG-43 in (192)Ir interstitial breast brachytherapy. A 57 patient cohort was used in a retrospective comparison between TG-43 based dosimetry data exported from a treatment planning system and Monte Carlo (MC) dosimetry performed using MCNP v. 6.1 with plan and anatomy information in DICOM-RT format. Comparison was performed for the target, ipsilateral lung, heart, skin, breast and ribs, using dose distributions, dose-volume histograms (DVH) and plan quality indices clinically used for plan evaluation, as well as radiobiological parameters. TG-43 overestimation of target DVH parameters is statistically significant but small (less than 2% for the target coverage indices and 4% for homogeneity indices, on average). Significant dose differences (>5%) were observed close to the skin and at relatively large distances from the implant leading to a TG-43 dose overestimation for the organs at risk. These differences correspond to low dose regions (<50% of the prescribed dose), being less than 2% of the prescribed dose. Detected dosimetric differences did not induce clinically significant differences in calculated tumor control probabilities (mean absolute difference <0.2%) and normal tissue complication probabilities. While TG-43 shows a statistically significant overestimation of most indices used for plan evaluation, differences are small and therefore not clinically significant. Improved MBDCA dosimetry could be important for re-irradiation, technique inter-comparison and/or the assessment of secondary cancer induction risk, where accurate dosimetry in the whole patient anatomy is of the essence. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  14. Multi-axis dose accumulation of noninvasive image-guided breast brachytherapy through biomechanical modeling of tissue deformation using the finite element method.

    Science.gov (United States)

    Rivard, Mark J; Ghadyani, Hamid R; Bastien, Adam D; Lutz, Nicholas N; Hepel, Jaroslaw T

    2015-02-01

    Noninvasive image-guided breast brachytherapy delivers conformal HDR (192)Ir brachytherapy treatments with the breast compressed, and treated in the cranial-caudal and medial-lateral directions. This technique subjects breast tissue to extreme deformations not observed for other disease sites. Given that, commercially-available software for deformable image registration cannot accurately co-register image sets obtained in these two states, a finite element analysis based on a biomechanical model was developed to deform dose distributions for each compression circumstance for dose summation. The model assumed the breast was under planar stress with values of 30 kPa for Young's modulus and 0.3 for Poisson's ratio. Dose distributions from round and skin-dose optimized applicators in cranial-caudal and medial-lateral compressions were deformed using 0.1 cm planar resolution. Dose distributions, skin doses, and dose-volume histograms were generated. Results were examined as a function of breast thickness, applicator size, target size, and offset distance from the center. Over the range of examined thicknesses, target size increased several millimeters as compression thickness decreased. This trend increased with increasing offset distances. Applicator size minimally affected target coverage, until applicator size was less than the compressed target size. In all cases, with an applicator larger or equal to the compressed target size, > 90% of the target covered by > 90% of the prescription dose. In all cases, dose coverage became less uniform as offset distance increased and average dose increased. This effect was more pronounced for smaller target-applicator combinations. The model exhibited skin dose trends that matched MC-generated benchmarking results within 2% and clinical observations over a similar range of breast thicknesses and target sizes. The model provided quantitative insight on dosimetric treatment variables over a range of clinical circumstances. These

  15. 3D-CRT, Proton, or Brachytherapy APBI in Treating Patients With Invasive and Non-invasive Breast Cancer

    Science.gov (United States)

    2017-12-29

    Ductal Breast Carcinoma In Situ; Estrogen Receptor Positive; Grade 1 Invasive Breast Carcinoma; Grade 2 Invasive Breast Carcinoma; Grade 3 Invasive Breast Carcinoma; Invasive Ductal and Lobular Carcinoma In Situ; Mucinous Breast Carcinoma; Tubular Breast Carcinoma

  16. Extended (5-year) Outcomes of Accelerated Partial Breast Irradiation Using MammoSite Balloon Brachytherapy: Patterns of Failure, Patient Selection, and Dosimetric Correlates for Late Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Vargo, John A.; Verma, Vivek; Kim, Hayeon; Kalash, Ronny; Heron, Dwight E.; Johnson, Ronald; Beriwal, Sushil, E-mail: beriwals@upmc.edu

    2014-02-01

    Purpose: Accelerated partial breast irradiation (APBI) with balloon and catheter-based brachytherapy has gained increasing popularity in recent years and is the subject of ongoing phase III trials. Initial data suggest promising local control and cosmetic results in appropriately selected patients. Long-term data continue to evolve but are limited outside of the context of the American Society of Breast Surgeons Registry Trial. Methods and Materials: A retrospective review of 157 patients completing APBI after breast-conserving surgery and axillary staging via high-dose-rate {sup 192}Ir brachytherapy from June 2002 to December 2007 was made. APBI was delivered with a single-lumen MammoSite balloon-based applicator to a median dose of 34 Gy in 10 fractions over a 5-day period. Tumor coverage and critical organ dosimetry were retrospectively collected on the basis of computed tomography completed for conformance and symmetry. Results: At a median follow-up time of 5.5 years (range, 0-10.0 years), the 5-year and 7-year actuarial incidences of ipsilateral breast control were 98%/98%, of nodal control 99%/98%, and of distant control 99%/99%, respectively. The crude rate of ipsilateral breast recurrence was 2.5% (n=4); of nodal failure, 1.9% (n=3); and of distant failure, 0.6% (n=1). The 5-year and 7-year actuarial overall survival rates were 89%/86%, with breast cancer–specific survival of 100%/99%, respectively. Good to excellent cosmetic outcomes were achieved in 93.4% of patients. Telangiectasia developed in 27% of patients, with 1-year, 3-year, and 5-year actuarial incidence of 7%/24%/33%; skin dose >100% significantly predicted for the development of telangiectasia (50% vs 14%, P<.0001). Conclusions: Long-term single-institution outcomes suggest excellent tumor control, breast cosmesis, and minimal late toxicity. Skin toxicity is a function of skin dose, which may be ameliorated with dosimetric optimization afforded by newer multicatheter brachytherapy

  17. Accelerated Partial Breast Irradiation With Low-Dose-Rate Interstitial Implant Brachytherapy After Wide Local Excision: 12-Year Outcomes From a Prospective Trial

    Energy Technology Data Exchange (ETDEWEB)

    Hattangadi, Jona A. [Harvard Radiation Oncology Program, Boston, MA (United States); Powell, Simon N. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); MacDonald, Shannon M.; Mauceri, Thomas; Ancukiewicz, Marek [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States); Freer, Phoebe [Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Lawenda, Brian [21st Century Oncology, Las Vegas, NV (United States); Alm El-Din, Mohamed A. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Department of Clinical Oncology, Tanta University Hospital, Tanta (Egypt); Gadd, Michele A.; Smith, Barbara L. [Department of Surgical Oncology, Massachusetts General Hospital, Boston, MA (United States); Taghian, Alphonse G., E-mail: ataghian@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA (United States)

    2012-07-01

    Purpose: To evaluate the long-term toxicity, cosmesis, and local control of accelerated partial breast irradiation with implant brachytherapy after wide local excision for Stage T1N0 breast cancer (BCa). Materials and Methods: Between 1997 and 2001, 50 patients with Stage T1N0M0 BCa were treated in a Phase I-II protocol using low-dose-rate accelerated partial breast irradiation with implant brachytherapy after wide local excision and lymph node surgery. The total dose was escalated in three groups: 50 Gy (n = 20), 55 Gy (n = 17), and 60 Gy (n = 13). Patient- and physician-assessed breast cosmesis, patient satisfaction, toxicity, mammographic abnormalities, repeat biopsies, and disease status were prospectively evaluated at each visit. Kendall's tau ({tau}{sub {beta}}) and logistic regression analyses were used to correlate outcomes with dose, implant volume, patient age, and systemic therapy. Results: The median follow-up period was 11.2 years (range, 4-14). The patient satisfaction rate was 67%, 67% reported good-excellent cosmesis, and 54% had moderate-severe fibrosis. Higher dose was correlated with worse cosmetic outcome ({tau}{sub {beta}} 0.6, p < .0001), lower patient satisfaction ({tau}{sub {beta}} 0.5, p < .001), and worse fibrosis ({tau}{sub {beta}} 0.4, p = .0024). Of the 50 patients, 35% had fat necrosis and 34% developed telangiectasias {>=}1 cm{sup 2}. Grade 3-4 late skin and subcutaneous toxicities were seen in 4 patients (9%) and 6 patients (13%), respectively, and both correlated with higher dose ({tau}{sub {beta}} 0.3-0.5, p {<=} .01). One patient had Grade 4 skin ulceration and fat necrosis requiring surgery. Mammographic abnormalities were seen in 32% of the patients, and 30% underwent repeat biopsy, of which 73% were benign. Six patients had ipsilateral breast recurrence: five elsewhere in the breast, and one at the implant site. One patient died of metastatic BCa after recurrence. The 12-year actuarial local control, recurrence

  18. SU-E-J-96: Multi-Axis Dose Accumulation of Noninvasive Image-Guided Breast Brachytherapy Through Biomechanical Modeling of Tissue Deformation Using the Finite Element Method

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, MJ [Tufts University School of Medicine, Boston, MA (United States); Ghadyani, HR [SUNY Farmingdale State College, Farmingdale, NY (United States); Bastien, AD; Lutz, NN [Univeristy Massachusetts Lowell, Lowell, MA (United States); Hepel, JT [Rhode Island Hospital, Providence, RI (United States)

    2015-06-15

    Purpose: Noninvasive image-guided breast brachytherapy delivers conformal HDR Ir-192 brachytherapy treatments with the breast compressed, and treated in the cranial-caudal and medial-lateral directions. This technique subjects breast tissue to extreme deformations not observed for other disease sites. Given that, commercially-available software for deformable image registration cannot accurately co-register image sets obtained in these two states, a finite element analysis based on a biomechanical model was developed to deform dose distributions for each compression circumstance for dose summation. Methods: The model assumed the breast was under planar stress with values of 30 kPa for Young’s modulus and 0.3 for Poisson’s ratio. Dose distributions from round and skin-dose optimized applicators in cranial-caudal and medial-lateral compressions were deformed using 0.1 cm planar resolution. Dose distributions, skin doses, and dose-volume histograms were generated. Results were examined as a function of breast thickness, applicator size, target size, and offset distance from the center. Results: Over the range of examined thicknesses, target size increased several millimeters as compression thickness decreased. This trend increased with increasing offset distances. Applicator size minimally affected target coverage, until applicator size was less than the compressed target size. In all cases, with an applicator larger or equal to the compressed target size, > 90% of the target covered by > 90% of the prescription dose. In all cases, dose coverage became less uniform as offset distance increased and average dose increased. This effect was more pronounced for smaller target-applicator combinations. Conclusions: The model exhibited skin dose trends that matched MC-generated benchmarking results and clinical measurements within 2% over a similar range of breast thicknesses and target sizes. The model provided quantitative insight on dosimetric treatment variables over

  19. Density-Based 3D Shape Descriptors

    Directory of Open Access Journals (Sweden)

    Schmitt Francis

    2007-01-01

    Full Text Available We propose a novel probabilistic framework for the extraction of density-based 3D shape descriptors using kernel density estimation. Our descriptors are derived from the probability density functions (pdf of local surface features characterizing the 3D object geometry. Assuming that the shape of the 3D object is represented as a mesh consisting of triangles with arbitrary size and shape, we provide efficient means to approximate the moments of geometric features on a triangle basis. Our framework produces a number of 3D shape descriptors that prove to be quite discriminative in retrieval applications. We test our descriptors and compare them with several other histogram-based methods on two 3D model databases, Princeton Shape Benchmark and Sculpteur, which are fundamentally different in semantic content and mesh quality. Experimental results show that our methodology not only improves the performance of existing descriptors, but also provides a rigorous framework to advance and to test new ones.

  20. Validation of a novel robot-assisted 3DUS system for real-time planning and guidance of breast interstitial HDR brachytherapy.

    Science.gov (United States)

    Poulin, Eric; Gardi, Lori; Barker, Kevin; Montreuil, Jacques; Fenster, Aaron; Beaulieu, Luc

    2015-12-01

    In current clinical practice, there is no integrated 3D ultrasound (3DUS) guidance system clinically available for breast brachytherapy. In this study, the authors present a novel robot-assisted 3DUS system for real-time planning and guidance of breast interstitial high dose rate (HDR) brachytherapy treatment. For this work, a new computer controlled robotic 3DUS system was built to perform a hybrid motion scan, which is a combination of a 6 cm linear translation with a 30° rotation at both ends. The new 3DUS scanner was designed to fit on a modified Kuske assembly, keeping the current template grid configuration but modifying the frame to allow the mounting of the 3DUS system at several positions. A finer grid was also tested. A user interface was developed to perform image reconstruction, semiautomatic segmentation of the surgical bed as well as catheter reconstruction and tracking. A 3D string phantom was used to validate the geometric accuracy of the reconstruction. The volumetric accuracy of the system was validated with phantoms using magnetic resonance imaging (MRI) and computed tomography (CT) images. In order to accurately determine whether 3DUS can effectively replace CT for treatment planning, the authors have compared the 3DUS catheter reconstruction to the one obtained from CT images. In addition, in agarose-based phantoms, an end-to-end procedure was performed by executing six independent complete procedures with both 14 and 16 catheters, and for both standard and finer Kuske grids. Finally, in phantoms, five end-to-end procedures were performed with the final CT planning for the validation of 3DUS preplanning. The 3DUS acquisition time is approximately 10 s. A paired Student t-test showed that there was no statistical significant difference between known and measured values of string separations in each direction. Both MRI and CT volume measurements were not statistically different from 3DUS volume (Student t-test: p > 0.05) and they were

  1. SU-E-J-215: Towards MR-Only Image Guided Identification of Calcifications and Brachytherapy Seeds: Application to Prostate and Breast LDR Implant Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Elzibak, A; Fatemi-Ardekani, A; Soliman, A; Mashouf, S; Safigholi, H; Ravi, A; Morton, G; Song, WY [Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Han, D [Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); University of California, San Diego, La Jolla, CA (United States)

    2015-06-15

    Purpose: To identify and analyze the appearance of calcifications and brachytherapy seeds on magnitude and phase MRI images and to investigate whether they can be distinguished from each other on corrected phase images for application to prostate and breast low dose rate (LDR) implant dosimetry. Methods: An agar-based gel phantom containing two LDR brachytherapy seeds (Advantage Pd-103, IsoAid, 0.8mm diameter, 4.5mm length) and two spherical calcifications (large: 7mm diameter and small: 4mm diameter) was constructed and imaged on a 3T Philips MR scanner using a 16-channel head coil and a susceptibility weighted imaging (SWI) sequence (2mm slices, 320mm FOV, TR/ TE= 26.5/5.3ms, 15 degree flip angle). The phase images were unwrapped and corrected using a 32×32, 2D Hanning high pass filter to remove background phase noise. Appearance of the seeds and calcifications was assessed visually and quantitatively using Osirix (http://www.osirix-viewer.com/). Results: As expected, calcifications and brachytherapy seeds appeared dark (hypointense) relative to the surrounding gel on the magnitude MRI images. The diameter of each seed without the surrounding artifact was measured to be 0.1 cm on the magnitude image, while diameters of 0.79 and 0.37 cm were measured for the larger and smaller calcifications, respectively. On the corrected phase images, the brachytherapy seeds and the calcifications appeared bright (hyperintense). The diameter of the seeds was larger on the phase images (0.17 cm) likely due to the dipole effect. Conclusion: MRI has the best soft tissue contrast for accurate organ delineation leading to most accurate implant dosimetry. This work demonstrated that phase images can potentially be useful in identifying brachytherapy seeds and calcifications in the prostate and breast due to their bright appearance, which helps in their visualization and quantification for accurate dosimetry using MR-only. Future work includes optimizing phase filters to best identify

  2. Dosimetric evaluation of multilumen intracavitary balloon applicator rotation in high-dose-rate brachytherapy for breast cancer.

    Science.gov (United States)

    Kim, Yongbok; Trombetta, Mark G

    2014-01-06

    The objective of this work is to evaluate dosimetric impact of multilumen balloon applicator rotation in high-dose-rate (HDR) brachytherapy for breast cancer. Highly asymmetrical dose distribution was generated for patients A and B, depending upon applicator proximity to skin and rib. Both skin and rib spacing was ≤ 0.7 cm for A; only rib spacing was ≤ 0.7 cm for B. Thirty-five rotation scenarios were simulated for each patient by rotating outer lumens every 10° over ± 180° range with respect to central lumen using mathematically calculated rotational matrix. Thirty-five rotated plans were compared with three plans: 1) original multidwell multilumen (MDML) plan, 2) multidwell single-lumen (MDSL) plan, and 3) single-dwell single-lumen (SDSL) plan. For plan comparison, planning target volume for evaluation (PTV_EVAL) coverage (dose to 95% and 90% volume of PTV_EVAL) (D95 and D90), skin and rib maximal dose (Dmax), and normal breast tissue volume receiving 150% (V150) and 200% (V200) of prescribed dose (PD) were evaluated. Dose variation due to device rotation ranged from -5.6% to 0.8% (A) and -6.5% to 0.2% (B) for PTV_EVAL D95; -5.2% to 0.4% (A) and -4.1% to 0.7% (B) for PTV_EVAL D90; -2.0 to 18.4% (A) and -7.8 to 17.5% (B) for skin Dmax; -11.1 to 22.8% (A) and -4.7 to 55.1% (B) of PD for rib Dmax, respectively. Normal breast tissue V150 and V200 variation was < 1.0 cc, except for -0.1 to 2.5cc (B) of V200. Furthermore, 30° device rotation increased rib Dmax over 145% of PD: 152.9% (A) by clockwise 30° rotation and 152.5% (B) by counterclockwise 30° rotation. For a highly asymmetric dose distribution, device rotation can outweigh the potential benefit of improved dose shaping capability afforded by multilumen and make dosimetric data worse than single-lumen plans unless it is properly corrected.

  3. Late side-effects and cosmetic results of accelerated partial breast irradiation with interstitial brachytherapy versus whole-breast irradiation after breast-conserving surgery for low-risk invasive and in-situ carcinoma of the female breast: 5-year results of a randomised, controlled, phase 3 trial.

    Science.gov (United States)

    Polgár, Csaba; Ott, Oliver J; Hildebrandt, Guido; Kauer-Dorner, Daniela; Knauerhase, Hellen; Major, Tibor; Lyczek, Jaroslaw; Guinot, José Luis; Dunst, Jürgen; Miguelez, Cristina Gutierrez; Slampa, Pavel; Allgäuer, Michael; Lössl, Kristina; Polat, Bülent; Kovács, György; Fischedick, Arnt-René; Fietkau, Rainer; Resch, Alexandra; Kulik, Anna; Arribas, Leo; Niehoff, Peter; Guedea, Ferran; Schlamann, Annika; Pötter, Richard; Gall, Christine; Uter, Wolfgang; Strnad, Vratislav

    2017-02-01

    We previously confirmed the non-inferiority of accelerated partial breast irradiation (APBI) with interstitial brachytherapy in terms of local control and overall survival compared with whole-breast irradiation for patients with early-stage breast cancer who underwent breast-conserving surgery in a phase 3 randomised trial. Here, we present the 5-year late side-effects and cosmetic results of the trial. We did this randomised, controlled, phase 3 trial at 16 centres in seven European countries. Women aged 40 years or older with stage 0-IIA breast cancer who underwent breast-conserving surgery with microscopically clear resection margins of at least 2 mm were randomly assigned 1:1, via an online interface, to receive either whole-breast irradiation of 50 Gy with a tumour-bed boost of 10 Gy or APBI with interstitial brachytherapy. Randomisation was stratified by study centre, menopausal status, and tumour type (invasive carcinoma vs ductal carcinoma in situ), with a block size of ten, according to an automated dynamic algorithm. Patients and investigators were not masked to treatment allocation. The primary endpoint of our initial analysis was ipsilateral local recurrence; here, we report the secondary endpoints of late side-effects and cosmesis. We analysed physician-scored late toxicities and patient-scored and physician-scored cosmetic results from the date of breast-conserving surgery to the date of onset of event. Analysis was done according to treatment received (as-treated population). This trial is registered with ClinicalTrials.gov, number NCT00402519. Between April 20, 2004, and July 30, 2009, we randomly assigned 1328 women to receive either whole-breast irradiation (n=673) or APBI with interstitial brachytherapy (n=655); 1184 patients comprised the as-treated population (551 in the whole-breast irradiation group and 633 in the APBI group). At a median follow-up of 6·6 years (IQR 5·8-7·6), no patients had any grade 4 toxities, and three (cosmetic

  4. Extended (5-year) outcomes of accelerated partial breast irradiation using MammoSite balloon brachytherapy: patterns of failure, patient selection, and dosimetric correlates for late toxicity.

    Science.gov (United States)

    Vargo, John A; Verma, Vivek; Kim, Hayeon; Kalash, Ronny; Heron, Dwight E; Johnson, Ronald; Beriwal, Sushil

    2014-02-01

    Accelerated partial breast irradiation (APBI) with balloon and catheter-based brachytherapy has gained increasing popularity in recent years and is the subject of ongoing phase III trials. Initial data suggest promising local control and cosmetic results in appropriately selected patients. Long-term data continue to evolve but are limited outside of the context of the American Society of Breast Surgeons Registry Trial. A retrospective review of 157 patients completing APBI after breast-conserving surgery and axillary staging via high-dose-rate (192)Ir brachytherapy from June 2002 to December 2007 was made. APBI was delivered with a single-lumen MammoSite balloon-based applicator to a median dose of 34 Gy in 10 fractions over a 5-day period. Tumor coverage and critical organ dosimetry were retrospectively collected on the basis of computed tomography completed for conformance and symmetry. At a median follow-up time of 5.5 years (range, 0-10.0 years), the 5-year and 7-year actuarial incidences of ipsilateral breast control were 98%/98%, of nodal control 99%/98%, and of distant control 99%/99%, respectively. The crude rate of ipsilateral breast recurrence was 2.5% (n=4); of nodal failure, 1.9% (n=3); and of distant failure, 0.6% (n=1). The 5-year and 7-year actuarial overall survival rates were 89%/86%, with breast cancer-specific survival of 100%/99%, respectively. Good to excellent cosmetic outcomes were achieved in 93.4% of patients. Telangiectasia developed in 27% of patients, with 1-year, 3-year, and 5-year actuarial incidence of 7%/24%/33%; skin dose >100% significantly predicted for the development of telangiectasia (50% vs 14%, PSkin toxicity is a function of skin dose, which may be ameliorated with dosimetric optimization afforded by newer multicatheter brachytherapy applicators and a more rigorous skin dose constraint of ≤100%. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. New era of electronic brachytherapy.

    Science.gov (United States)

    Ramachandran, Prabhakar

    2017-04-28

    Traditional brachytherapy refers to the placement of radioactive sources on or inside the cancer tissues. Based on the type of sources, brachytherapy can be classified as radionuclide and electronic brachytherapy. Electronic brachytherapy uses miniaturized X-ray sources instead of radionuclides to deliver high doses of radiation. The advantages of electronic brachytherapy include low dose to organs at risk, reduced dose to treating staff, no leakage radiation in off state, less shielding, and no radioactive waste. Most of these systems operate between 50 and 100 kVp and are widely used in the treatment of skin cancer. Intrabeam, Xoft and Papillon systems are also used in the treatment of intra-operative radiotherapy to breast in addition to other treatment sites. The rapid fall-off in the dose due to its low energy is a highly desirable property in brachytherapy and results in a reduced dose to the surrounding normal tissues compared to the Ir-192 source. The Xoft Axxent brachytherapy system uses a 2.25 mm miniaturized X-ray tube and the source almost mimics the high dose rate Ir-192 source in terms of dose rate and it is the only electronic brachytherapy system specifically used in the treatment of cervical cancers. One of the limiting factors that impede the use of electronic brachytherapy for interstitial application is the source dimension. However, it is highly anticipated that the design of miniaturized X-ray tube closer to the dimension of an Ir-192 wire is not too far away, and the new era of electronic brachytherapy has just begun.

  6. New era of electronic brachytherapy

    Science.gov (United States)

    Ramachandran, Prabhakar

    2017-01-01

    Traditional brachytherapy refers to the placement of radioactive sources on or inside the cancer tissues. Based on the type of sources, brachytherapy can be classified as radionuclide and electronic brachytherapy. Electronic brachytherapy uses miniaturized X-ray sources instead of radionuclides to deliver high doses of radiation. The advantages of electronic brachytherapy include low dose to organs at risk, reduced dose to treating staff, no leakage radiation in off state, less shielding, and no radioactive waste. Most of these systems operate between 50 and 100 kVp and are widely used in the treatment of skin cancer. Intrabeam, Xoft and Papillon systems are also used in the treatment of intra-operative radiotherapy to breast in addition to other treatment sites. The rapid fall-off in the dose due to its low energy is a highly desirable property in brachytherapy and results in a reduced dose to the surrounding normal tissues compared to the Ir-192 source. The Xoft Axxent brachytherapy system uses a 2.25 mm miniaturized X-ray tube and the source almost mimics the high dose rate Ir-192 source in terms of dose rate and it is the only electronic brachytherapy system specifically used in the treatment of cervical cancers. One of the limiting factors that impede the use of electronic brachytherapy for interstitial application is the source dimension. However, it is highly anticipated that the design of miniaturized X-ray tube closer to the dimension of an Ir-192 wire is not too far away, and the new era of electronic brachytherapy has just begun. PMID:28529679

  7. Outcomes in women treated with MammoSite brachytherapy or whole breast irradiation stratified by ASTRO Accelerated Partial Breast Irradiation Consensus Statement Groups.

    Science.gov (United States)

    Zauls, A Jason; Watkins, John M; Wahlquist, Amy E; Brackett, N Craig; Aguero, Eric G; Baker, Megan K; Jenrette, Joseph M; Garrett-Mayer, Elizabeth; Harper, Jennifer L

    2012-01-01

    The American Society for Radiation Oncology published a Consensus Statement for accelerated partial breast irradiation identifying three groups: Suitable, Cautionary, and Unsuitable. The objective of this study was to compare oncologic outcomes in women treated with MammoSite brachytherapy (MB) vs. whole breast irradiation (WBI) after stratification into Statement groups. Eligible women had invasive carcinoma or ductal carcinoma in situ (DCIS) ≤ 3 cm, and ≤ 3 lymph nodes positive. Women were stratified by radiation modality and Statement groups. Survival analysis methods including Kaplan-Meier estimation, Cox regression, and competing risks analysis were used to assess overall survival (OS), disease-free survival (DFS), time to local failure (TTLF), and tumor bed failure (TBF). A total of 459 (183 MB and 276 WBI) patients were treated from 2002 to 2009. After a median follow-up of 45 months, we found no statistical differences by stratification group or radiation modality with regard to OS and DFS. At 4 years TTLF or TBF were not statistically different between the cohorts. Univariate analysis in the MB cohort revealed that nodal positivity (pN1 vs. pN0) was related to TTLF (hazard ratio 6.39, p = 0.02). There was a suggestion that DCIS histology had an increased risk of failure when compared with invasive ductal carcinoma (hazard ratio 3.57, p = 0.06). MB and WBI patients stratified by Statement groups seem to combine women who will have similar outcomes regardless of radiation modality. Although outcomes were similar, we remain guarded in overinterpretation of these preliminary results until further analysis and long-term follow-up data become available. Caution should be used in treating women with DCIS or pN1 disease with MB. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Outcomes in Women Treated With MammoSite Brachytherapy or Whole Breast Irradiation Stratified by ASTRO Accelerated Partial Breast Irradiation Consensus Statement Groups

    Energy Technology Data Exchange (ETDEWEB)

    Zauls, A. Jason, E-mail: zauls@musc.edu [Department of Radiation Oncology, Medical University of South Carolina, Charleston, SC (United States); Watkins, John M. [Department of Radiation Oncology, Medical University of South Carolina, Charleston, SC (United States); Wahlquist, Amy E. [Department of Biostatistics, Bioinformatics, and Epidemiology, Medical University of South Carolina, Charleston, SC (United States); Brackett, N. Craig [Coastal Carolina Breast Center, Georgetown, SC (United States); Aguero, Eric G. [Department of Radiation Oncology, Medical University of South Carolina, Charleston, SC (United States); Baker, Megan K. [Department of Surgery, Medical University of South Carolina, Charleston, SC (United States); Jenrette, Joseph M. [Department of Radiation Oncology, Medical University of South Carolina, Charleston, SC (United States); Garrett-Mayer, Elizabeth [Department of Biostatistics, Bioinformatics, and Epidemiology, Medical University of South Carolina, Charleston, SC (United States); Harper, Jennifer L. [Department of Radiation Oncology, Medical University of South Carolina, Charleston, SC (United States)

    2012-01-01

    Purpose: The American Society for Radiation Oncology published a Consensus Statement for accelerated partial breast irradiation identifying three groups: Suitable, Cautionary, and Unsuitable. The objective of this study was to compare oncologic outcomes in women treated with MammoSite brachytherapy (MB) vs. whole breast irradiation (WBI) after stratification into Statement groups. Methods: Eligible women had invasive carcinoma or ductal carcinoma in situ (DCIS) {<=}3 cm, and {<=}3 lymph nodes positive. Women were stratified by radiation modality and Statement groups. Survival analysis methods including Kaplan-Meier estimation, Cox regression, and competing risks analysis were used to assess overall survival (OS), disease-free survival (DFS), time to local failure (TTLF), and tumor bed failure (TBF). Results: A total of 459 (183 MB and 276 WBI) patients were treated from 2002 to 2009. After a median follow-up of 45 months, we found no statistical differences by stratification group or radiation modality with regard to OS and DFS. At 4 years TTLF or TBF were not statistically different between the cohorts. Univariate analysis in the MB cohort revealed that nodal positivity (pN1 vs. pN0) was related to TTLF (hazard ratio 6.39, p = 0.02). There was a suggestion that DCIS histology had an increased risk of failure when compared with invasive ductal carcinoma (hazard ratio 3.57, p = 0.06). Conclusions: MB and WBI patients stratified by Statement groups seem to combine women who will have similar outcomes regardless of radiation modality. Although outcomes were similar, we remain guarded in overinterpretation of these preliminary results until further analysis and long-term follow-up data become available. Caution should be used in treating women with DCIS or pN1 disease with MB.

  9. Dosimetric experience with 2 commercially available multilumen balloon-based brachytherapy to deliver accelerated partial-breast irradiation.

    Science.gov (United States)

    Fu, Weihua; Kim, Jong Oh; Chen, Alex S J; Mehta, Kiran; Pucci, Pietro; Huq, M Saiful

    2015-01-01

    The purpose of this work was to report dosimetric experience with 2 kinds of multilumen balloon (MLB), 5-lumen Contura MLB (C-MLB) and 4-lumen MammoSite MLB (MS-MLB), to deliver accelerated partial-breast irradiation, and compare the ability to achieve target coverage and control skin and rib doses between 2 groups of patients treated with C-MLB and MS-MLB brachytherapy. C-MLB has 5 lumens, the 4 equal-spaced peripheral lumens are 5 mm away from the central lumen. MS-MLB has 4 lumens, the 3 equal-spaced peripheral lumens are 3 mm away from the central lumen. In total, 43 patients were treated, 23 with C-MLB, and 20 with MS-MLB. For C-MLB group, 8 patients were treated with a skin spacing skin spacing skin dose ≤ 125% of the PD, (3) maximum rib dose ≤ 145% of the PD (if possible), and (4) the V(150%) ≤ 50 cm(3) and V(200%) ≤ 10 cm(3). All dosimetric criteria were met concurrently in 82.6% of C-MLB patients, in 80.0% of MS-MLB patients, and in 81.4% of all 43 patients. For each dosimetric parameter, t-test of these 2 groups showed p > 0.05. Although the geometric design of C-MLB is different from that of MS-MLB, both applicators have the ability to shape the dose distribution and to provide good target coverage, while limiting the dose to skin and rib. No significant difference was observed between the 2 patient groups in terms of target dose coverage and dose to organs at risk. Copyright © 2015 American Association of Medical Dosimetrists. Published by Elsevier Inc. All rights reserved.

  10. Three-year clinical outcome using the Contura multilumen balloon breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI): improving radiation standards for the optimal application of APBI.

    Science.gov (United States)

    Israel, Philip Z; Robbins, Angela; Shroff, Paulomi; Brown, Sheree; McLaughlin, Mark; Pope, Keith

    2012-01-01

    We reviewed our institution's 3-year clinical experience in treating patients with the Contura multilumen balloon (SenoRx, Inc., Aliso Viejo, CA) breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI). Forty-six patients treated with breast-conserving therapy received adjuvant radiation using the Contura catheter (34Gy in 3.4Gy fractions). Fourteen patients had Stage 0, 24 had Stage I, and 8 had Stage II breast cancer. Median follow-up was 36 months (range, 1-44 months). Only one local recurrence developed (2%). The rate of persistent seroma formation at latest reported follow-up was 4.3% (2 patients) and the incidence of any clinically detectable telengiectasias was 2.2%. No major toxicities (0% Grade III) have occurred. The median skin dose (% of the prescribed dose) was 99.7. The median dose to 95% of the planning target volume for evaluation was 98.8%. The percentage of patients with excellent/good cosmetic results at 24 (n=23) and 36 (n=22) months was 100% and 97%, respectively. Adjuvant APBI using the Contura multilumen balloon catheter exhibited similar locoregional control, cosmesis, and toxicities to other forms of APBI with similar lengths of follow-up. In addition, improved radiation standards for the delivery of APBI were demonstrated. Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  11. Concepts for critical organ dosimetry in three-dimensional image-based breast brachytherapy.

    Science.gov (United States)

    Berger, Daniel; Kauer-Dorner, Daniela; Seitz, Wolfgang; Pötter, Richard; Kirisits, Christian

    2008-01-01

    To investigate dose-volume histogram (DVH) parameters for organs at risk (OARs) in sectional three-dimensional image-based accelerated partial breast irradiation. Skin, lung, and ribs were defined as OARs and the heart was discussed. Two different skin-contouring methods were tested on phantom before applying to the patient cohort. First, an inside skin wall contour was delineated with three different wall thicknesses to demonstrate the influence of contouring on DVH parameter. Second a structure was defined, delineated outside of the phantom surface, such that a three-dimensional skin volume was extended like a virtual bolus contour. Point dose values and DVH parameters were reported for 25 patient cases. The DVH parameters D0.1 cc = 65+/-21, D1 cc = 45+/-8, and D10 cc = 30+/-4 cGy/pulse for the outside skin structure around the breast corresponded to skin surface areas of 1+/-1, 6+/-3, and 6+/-11cm2. Lung volume receiving 20 Gyalphabeta3 was 8.3+/-11cm3. D0.1 cc and D2 cc in the most exposed rib were 0.7+/-0.3 and 0.4+/-0.2 Gy/pulse, respectively. In accelerated partial breast irradiation treatment planning, dose to OAR can be reported in a more sophisticated way with DVH parameters than using points only. The suggested method of skin delineation using the defined outside structure allows calculating reliable and reproducible DVH parameters.

  12. Factors Associated With Optimal Long-Term Cosmetic Results in Patients Treated With Accelerated Partial Breast Irradiation Using Balloon-Based Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Vicini, Frank A., E-mail: fvicini@beaumont.edu [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States); Keisch, Martin [Miami Brachytherapy Center, Cancer Healthcare Associates, Miami, FL (United States); Shah, Chirag [Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI (United States); Goyal, Sharad; Khan, Atif J. [Department of Radiation Oncology, Cancer Institute of New Jersey, New Brunswick, NJ (United States); Beitsch, Peter D. [Dallas Breast Center, Dallas, TX (United States); Lyden, Maureen [BioStat International Inc, Tampa, FL (United States); Haffty, Bruce G. [Department of Radiation Oncology, Cancer Institute of New Jersey, New Brunswick, NJ (United States)

    2012-06-01

    Purpose: To evaluate factors associated with optimal cosmetic results at 72 months for early-stage breast cancer patients treated with Mammosite balloon-based accelerated partial breast irradiation (APBI). Methods and Materials: A total of 1,440 patients (1,449 cases) with early-stage breast cancer undergoing breast-conserving therapy were treated with balloon-based brachytherapy to deliver APBI (34 Gy in 3.4-Gy fractions). Cosmetic outcome was evaluated at each follow-up visit and dichotomized as excellent/good (E/G) or fair/poor (F/P). Follow-up was evaluated at 36 and 72 months to establish long-term cosmesis, stability of cosmesis, and factors associated with optimal results. Results: The percentage of evaluable patients with excellent/good (E/G) cosmetic results at 36 months and more than 72 months were 93.3% (n = 708/759) and 90.4% (n = 235/260). Factors associated with optimal cosmetic results at 72 months included: larger skin spacing (p = 0.04) and T1 tumors (p = 0.02). Using multiple regression analysis, the only factors predictive of worse cosmetic outcome at 72 months were smaller skin spacing (odds ratio [OR], 0.89; confidence interval [CI], 0.80-0.99) and tumors greater than 2 cm (OR, 4.96, CI, 1.53-16.07). In all, 227 patients had both a 36-month and a 72-month cosmetic evaluation. The number of patients with E/G cosmetic results decreased only slightly from 93.4% at 3 years to 90.8% (p = 0.13) at 6 years, respectively. Conclusions: APBI delivered with balloon-based brachytherapy produced E/G cosmetic results in 90.4% of cases at 6 years. Larger tumors (T2) and smaller skin spacing were found to be the two most important independent predictors of cosmesis.

  13. A Single-Site Retrospective, Nonrandomized Study of Accelerated Partial Breast Irradiation Brachytherapy for Early-Stage Breast Cancer Treatment to Evaluate Local Tumor Control, Cosmetic Outcome, and Toxicities.

    Science.gov (United States)

    Shah, Shalin; Holzwanger, Erik; Khwaja, Radhika; Fang, Deborah; Figueroa-Bodine, Jazmin; Iannuzzi, Christopher; Shi, Chengyu

    2016-10-01

    To evaluate the efficacy and safety of the accelerated partial breast irradiation brachytherapy with a combination of applicators at a community hospital cancer center. Between 2005 and 2009, 120 patients with early-stage breast cancer were being followed after treatment with accelerated partial breast irradiation brachytherapy using MammoSite, single or multilumen balloon, or Contura multilumen balloon. After their lumpectomy surgery, each patient was treated with Ir-192 high-dose rate unit following radiation therapy oncology group 0413 guidelines. The patients had multiple follow-ups at 6 months, 1 year, 2 years, 3 years, or more. Based on the Harvard Breast Cosmesis Scale, 95.00% of patients described their cosmetic evaluation as the treated breast essentially the same as the opposite side (excellent) or minimal but identifiable effects were noticed from radiation (good). After a median follow-up of 36 months, the local recurrence rate was 1.66% and a disease-free survival is 98.3%. Forty-two patients reported 85 adverse events, which were fibrosis: 24.70%, hyperpigmentation: 20.00%, radiation skin reaction: 7.05%, seroma: 7.05%, breast pain: 7.05%, erythema: 5.88%, and other events were less than 5.00%. Of all the adverse events recorded, grade 1 to 3 events are 95.29% (n = 81), 2.35% (n = 2), and 2.35% (n = 2). There was no grade 4 or 5 events recorded. Our study has shown promising results for delivering radiation with MammoSite, single or multilumen balloon, or Contura multilumen balloon and has been successful in achieving local control in patients with early-stage breast cancer. © The Author(s) 2015.

  14. Objective and Longitudinal Assessment of Dermatitis After Postoperative Accelerated Partial Breast Irradiation Using High-Dose-Rate Interstitial Brachytherapy in Patients With Breast Cancer Treated With Breast Conserving Therapy: Reduction of Moisture Deterioration by APBI

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Eiichi [Department of Radiation Oncology, National Hospital Organization, Osaka National Hospital, Osaka (Japan); Yamazaki, Hideya, E-mail: hideya10@hotmail.com [Department of Radiology, Kyoto Prefectural University of Medicine, Kyoto (Japan); Yoshida, Ken; Takenaka, Tadashi [Department of Radiation Oncology, National Hospital Organization, Osaka National Hospital, Osaka (Japan); Masuda, Norikazu [Department of Surgery and Breast Oncology, National Hospital Organization, Osaka National Hospital, Osaka (Japan); Kotsuma, Tadayuki; Yoshioka, Yasuo; Inoue, Takehiro [Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita (Japan)

    2011-11-15

    Purpose: To objectively evaluate the radiation dermatitis caused by accelerated partial breast irradiation (APBI) using high-dose-rate interstitial brachytherapy. Patients and Methods: The skin color and moisture changes were examined using a newly installed spectrophotometer and corneometer in 22 patients who had undergone APBI using open cavity implant high-dose-rate interstitial brachytherapy (36 Gy in six fractions) and compared with the corresponding values for 44 patients in an external beam radiotherapy (EBRT) control group (50-60 Gy in 25-30 fractions within 5-6 weeks) after breast conserving surgery. Results: All values changed significantly as a result of APBI. The extent of elevation in a Asterisk-Operator (reddish) and reduction in L Asterisk-Operator (black) values caused by APBI were similar to those for EBRT, with slightly delayed recovery for 6-12 months after treatment owing to the surgical procedure. In contrast, only APBI caused a change in the b Asterisk-Operator values, and EBRT did not, demonstrating that the reduction in b Asterisk-Operator values (yellowish) depends largely on the surgical procedure. The changes in moisture were less severe after APBI than after EBRT, and the recovery was more rapid. The toxicity assessment using the Common Toxicity Criteria, version 3, showed that all dermatitis caused by APBI was Grade 2 or less. Conclusion: An objective analysis can quantify the effects of APBI procedures on color and moisture cosmesis. The radiation dermatitis caused by APBI using the present schedule showed an equivalent effect on skin color and a less severe effect on moisture than the effects caused by standard EBRT.

  15. SU-E-T-58: Calculation of Dose Distribution of Accuboost Brachytherapy in Deformable Polyvinil Alcohol Breast Phantom Using Biomechanical Modeling and Monte Carlo Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Mohammadyari, P [Nuclear Engineering Department, School of Mechanical Engineering, Shiraz Un, Ilam (Iran, Islamic Republic of); Faghihi, R [Nuclear Engineering Department, Shiraz University, Shiraz (Iran, Islamic Republic of); Shirazi, M Mosleh [Radiotherapy and Oncology Department, Namazi Hospital, Shiraz University of M, Shiraz (Iran, Islamic Republic of); Lotfi, M [Shiraz University of Medical Sciences, Medical Imaging Research Center, Shiraz (Iran, Islamic Republic of); Meigooni, A [Comprehensive cancer center of Nevada - University of Nevada Las Vegas UNL, Las Vegas, NV (United States)

    2014-06-01

    Purpose: the accuboost is the most modern method of breast brachytherapy that is a boost method in compressed tissue by a mammography unit. the dose distribution in uncompressed tissue, as compressed tissue is important that should be characterized. Methods: In this study, the mechanical behavior of breast in mammography loading, the displacement of breast tissue and the dose distribution in compressed and uncompressed tissue, are investigated. Dosimetry was performed by two dosimeter methods of Monte Carlo simulations using MCNP5 code and thermoluminescence dosimeters. For Monte Carlo simulations, the dose values in cubical lattice were calculated using tally F6. The displacement of the breast elements was simulated by Finite element model and calculated using ABAQUS software, from which the 3D dose distribution in uncompressed tissue was determined. The geometry of the model is constructed from MR images of 6 volunteers. Experimental dosimetery was performed by placing the thermoluminescence dosimeters into the polyvinyl alcohol breast equivalent phantom and on the proximal edge of compression plates to the chest. Results: The results indicate that using the cone applicators would deliver more than 95% of dose to the depth of 5 to 17mm, while round applicator will increase the skin dose. Nodal displacement, in presence of gravity and 60N forces, i.e. in mammography compression, was determined with 43% contraction in the loading direction and 37% expansion in orthogonal orientation. Finally, in comparison of the acquired from thermoluminescence dosimeters with MCNP5, they are consistent with each other in breast phantom and in chest's skin with average different percentage of 13.7±5.7 and 7.7±2.3, respectively. Conclusion: The major advantage of this kind of dosimetry is the ability of 3D dose calculation by FE Modeling. Finally, polyvinyl alcohol is a reliable material as a breast tissue equivalent dosimetric phantom that provides the ability of TLD

  16. Dosimetric experience with 2 commercially available multilumen balloon-based brachytherapy to deliver accelerated partial-breast irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Weihua, E-mail: fuw@upmc.edu; Kim, Jong Oh; Chen, Alex S.J.; Mehta, Kiran; Pucci, Pietro; Huq, M. Saiful

    2015-10-01

    The purpose of this work was to report dosimetric experience with 2 kinds of multilumen balloon (MLB), 5-lumen Contura MLB (C-MLB) and 4-lumen MammoSite MLB (MS-MLB), to deliver accelerated partial-breast irradiation, and compare the ability to achieve target coverage and control skin and rib doses between 2 groups of patients treated with C-MLB and MS-MLB brachytherapy. C-MLB has 5 lumens, the 4 equal-spaced peripheral lumens are 5 mm away from the central lumen. MS-MLB has 4 lumens, the 3 equal-spaced peripheral lumens are 3 mm away from the central lumen. In total, 43 patients were treated, 23 with C-MLB, and 20 with MS-MLB. For C-MLB group, 8 patients were treated with a skin spacing < 7 mm and 12 patients with rib spacing < 7 mm. For MS-MLB group, 2 patients were treated with a skin spacing < 7 mm and 5 patients with rib spacing < 7 mm. The dosimetric goals were (1) ≥ 95% of the prescription dose (PD) covering ≥ 95% of the target volume (V{sub 95%} ≥ 95%), (2) maximum skin dose ≤ 125% of the PD, (3) maximum rib dose ≤ 145% of the PD (if possible), and (4) the V{sub 150%} ≤ 50 cm{sup 3} and V{sub 200%} ≤ 10 cm{sup 3}. All dosimetric criteria were met concurrently in 82.6% of C-MLB patients, in 80.0% of MS-MLB patients, and in 81.4% of all 43 patients. For each dosimetric parameter, t-test of these 2 groups showed p > 0.05. Although the geometric design of C-MLB is different from that of MS-MLB, both applicators have the ability to shape the dose distribution and to provide good target coverage, while limiting the dose to skin and rib. No significant difference was observed between the 2 patient groups in terms of target dose coverage and dose to organs at risk.

  17. SU-F-T-01: Optimization of the Accelerated Partial Breast Brachytherapy Fractionation with Consideration of Physical Doses to Tumor and Organ at Risk

    Energy Technology Data Exchange (ETDEWEB)

    Fu, W; Huq, M [University of Pittsburgh Cancer Institute Pittsburgh, PA (United States)

    2016-06-15

    Purpose: The accelerated partial breast irradiation (APBI) with brachytherapy prescribes 34Gy to be delivered in 10 fractions over 5 consecutive working days without considering the physical dose to the target and organs at risk (OARs) for an individual patient. The purpose of this study is to optimize the fractionation scheme by evaluating the radiation effect on tumor and OARs with a modified linear-quadratic (LQ) model based on dose-volume histograms (DVHs). Methods: Five breast patients treated with multilumen balloon brachytherapy were selected. The minimum skin and rib spacing were ranged from 2.5mm to 14.3mm and from 1.0mm to 25.0mm, respectively. The LQ model parameters were set as: (1) breast: α=0.08, β=0.028, doubling time Tpot=14.4 days, and starting time Tk=21days; (2) skin: acute reaction α=0.101, β=0.009; late reaction α=0.064, β=0.029; (3) rib: α=0.3, β=0.12. Boundary dose Dt was 6 Gy for both target and OARs. The relation between radiation effects on the tumor (ET) and OARs (EOAR) were plotted for fraction number from 1 to 20. Results: The value of radiation effect from routine 3.4Gyx10 fractions was used as reference, ETref and EOARref. If set ET=ETref, the fractionation that results in minimum EOAR values correspond to the optimal fractionation. For these patients, the optimal numbers are 10 fractions for skin acute reaction, 18 fractions for skin and rib late reaction while the doses per fraction are 3.4Gy and 2.05–2.10Gy, respectively. If set EOAR=EOARref, the fractionation that results in a maximum ET value corresponds to the optimal fractionation. The optimal fractionation is 3.4Gyx10 fractions for skin acute reaction, and 2.10–2.25Gyx18 fractions for skin late reaction and rib. Conclusion: For APBI brachytherapy, the routine 3.4Gyx10 fractions is optimal fractionation for skin acute reaction, while 2.05–2.25Gyx18 fractions is optimal fractionation for late reaction of skin and rib.

  18. Cosmetic changes following surgery and accelerated partial breast irradiation using HDR interstitial brachytherapy : Evaluation by a multidisciplinary/multigender committee.

    Science.gov (United States)

    Soror, Tamer; Kovács, György; Seibold, Nina; Melchert, Corinna; Baumann, Kristin; Wenzel, Eike; Stojanovic-Rundic, Suzana

    2017-05-01

    Patients with early-stage breast cancer can benefit from adjuvant accelerated partial breast irradiation (APBI) following breast-conserving surgery (BCS). This work reports on cosmetic results following APBI using multicatheter high-dose-rate interstitial brachytherapy (HDR-IBT). Between 2006 and 2014, 114 patients received adjuvant APBI using multicatheter HDR-IBT. For each patient, two photographs were analyzed: the first was taken after surgery (baseline image) and the second at the last follow-up visit. Cosmesis was assessed by a multigender multidisciplinary team using the Harvard Breast Cosmesis Scale. Dose-volume histogram (DVH) parameters and the observed cosmetic results were investigated for potential correlations. The median follow-up period was 3.5 years (range 0.6-8.5 years). The final cosmetic scores were 30% excellent, 52% good, 14.5% fair, and 3.5% poor. Comparing the baseline and follow-up photographs, 59.6% of patients had the same score, 36% had a better final score, and 4.4% had a worse final score. Only lower target dose nonuniformity ratio (DNR) values (0.3 vs. 0.26; p = 0.009) were significantly associated with improved cosmetic outcome vs. same/worse cosmesis. APBI using multicatheter HDR-IBT adjuvant to BCS results in favorable final cosmesis. Deterioration in breast cosmesis occurs in less than 5% of patients. The final breast cosmetic outcome in patients treated with BCS and APBI using multicatheter HDR-IBT is influenced primarily by the cosmetic result of the surgery. A lower DNR value is significantly associated with a better cosmetic outcome.

  19. Validation of a novel robot-assisted 3DUS system for real-time planning and guidance of breast interstitial HDR brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Poulin, Eric; Beaulieu, Luc, E-mail: Luc.Beaulieu@phy.ulaval.ca [Département de Physique, de Génie Physique et d’optique et Centre de Recherche sur le Cancer de l’Université Laval, Université Laval, Québec, Québec G1V 0A6, Canada and Département de Radio-oncologie et Axe Oncologie du Centre de Recherche du CHU de Québec, CHU de Québec, 11 Côte du Palais, Québec, Québec G1R 2J6 (Canada); Gardi, Lori; Barker, Kevin; Montreuil, Jacques; Fenster, Aaron [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (Canada)

    2015-12-15

    Purpose: In current clinical practice, there is no integrated 3D ultrasound (3DUS) guidance system clinically available for breast brachytherapy. In this study, the authors present a novel robot-assisted 3DUS system for real-time planning and guidance of breast interstitial high dose rate (HDR) brachytherapy treatment. Methods: For this work, a new computer controlled robotic 3DUS system was built to perform a hybrid motion scan, which is a combination of a 6 cm linear translation with a 30° rotation at both ends. The new 3DUS scanner was designed to fit on a modified Kuske assembly, keeping the current template grid configuration but modifying the frame to allow the mounting of the 3DUS system at several positions. A finer grid was also tested. A user interface was developed to perform image reconstruction, semiautomatic segmentation of the surgical bed as well as catheter reconstruction and tracking. A 3D string phantom was used to validate the geometric accuracy of the reconstruction. The volumetric accuracy of the system was validated with phantoms using magnetic resonance imaging (MRI) and computed tomography (CT) images. In order to accurately determine whether 3DUS can effectively replace CT for treatment planning, the authors have compared the 3DUS catheter reconstruction to the one obtained from CT images. In addition, in agarose-based phantoms, an end-to-end procedure was performed by executing six independent complete procedures with both 14 and 16 catheters, and for both standard and finer Kuske grids. Finally, in phantoms, five end-to-end procedures were performed with the final CT planning for the validation of 3DUS preplanning. Results: The 3DUS acquisition time is approximately 10 s. A paired Student t-test showed that there was no statistical significant difference between known and measured values of string separations in each direction. Both MRI and CT volume measurements were not statistically different from 3DUS volume (Student t-test: p > 0

  20. Optimization and comparison of balloon-based partial breast brachytherapy using a single source, a standard plan line source, and both forward and inverse planned multilumen techniques.

    Science.gov (United States)

    Eyre, Katie; Whitney, Diane; Mukesh, Mukesh; Wilson, Charles; Coles, Charlotte

    2013-01-01

    This study directly compares four dosimetric techniques for balloon-based partial breast brachytherapy: single source, standard line source, and both forward planned and inverse planned multilumen (ML). A standard line source plan is presented to be used in a single catheter or as a starting point for forward planned ML. The study population consists of 12 patients previously treated with a single lumen. Inverse plans were created for 7 patients and used to create a standard line source plan. ML plans were created on the same patient data sets. The dosimetric aims were as follows: PTV_EVAL (planning target volume for evaluation) D95 (dose received [%] by 95% of PTV_EVAL volume)≥95% of the prescribed dose (PD), the maximum skin and rib dose ≤125% of prescription dose, breast V150 (volume [cc] receiving 150% of the PD)≤50cc, and V200 (volume [cc] receiving 200% of the PD)≤10cc. The number of patients fulfilling all dosimetric constraints went from 1 patient of 12 with a single catheter to 6 patients of 12 with inverse planned ML and 7 patients of 12 with forward planned ML. PTV_EVAL D95 increased significantly with the standard line source plans and ML plans when compared with the single-source plans. Forward planning took, on average, 7min longer than inverse planning. Multiple sources in a single catheter improve coverage at catheter ends, whereas ML can further improve coverage and reduce dose to organs at risk. Using a standard line source as a starting point for forward planning ML means increase in planning time is kept to a minimum, making it a practicable option for centers without inverse planning software. Patients previously ineligible for treatment with a single catheter may be treated using ML. Copyright © 2013 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  1. A dosimetric comparison of the Contura multilumen balloon breast brachytherapy catheter vs. the single-lumen MammoSite balloon device in patients treated with accelerated partial breast irradiation at a single institution.

    Science.gov (United States)

    Brown, Sheree; McLaughlin, Mark; Pope, Doyle Keith; Haile, Kenneth; Hughes, Lorie; Israel, Philip Z; Lyden, Maureen

    2011-01-01

    A comparison of dosimetric findings in 33 patients treated with the Contura multilumen balloon (SenoRx Inc., Irvine, CA) (C-MLB) breast brachytherapy catheter vs. 33 patients treated with the MammoSite (Hologic Inc., Bedford, MA) (MS) at a single institution to deliver accelerated partial breast irradiation (APBI) was performed. CT-based 3-dimensional planning with dose optimization was completed. APBI treatment of 34Gy in 3.4Gy fractions was delivered. Endpoints analyzed included: (1) The percentage of the prescribed dose (PD) covering the planning target volume (PTV), (2) the maximum skin dose as a percentage of the PD, (3) the maximum rib dose as a percentage of the PD, and (4) the V150 and V200. The C-MLB was placed more frequently in patients with closer skin spacing (skin spacing, the overall median skin dose was significantly lower in C-MLB patients (112% of the PD vs. 134%, p=0.0282). No statistically significant differences in the V150 or V200 were observed. In patients with very limited rib spacing (skin and rib doses and improved PTV coverage) in most clinical scenarios. Copyright © 2011 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  2. External radiation and HDR-brachytherapy in the treatment of breast cancer. Externe Bestrahlung und interstitielle HDR-Brachytherapie in der Bestrahlung des Mammakarzinoms

    Energy Technology Data Exchange (ETDEWEB)

    Track, C. (Abt. fuer Radioonkologie, Krankenhaus der Barmherzigen Schwestern, Linz (Austria)); Seewald, D.H. (Abt. fuer Radioonkologie, Krankenhaus der Barmherzigen Schwestern, Linz (Austria)); Zoidl, J.P. (Abt. fuer Radioonkologie, Krankenhaus der Barmherzigen Schwestern, Linz (Austria)); Hammer, J. (Abt. fuer Radioonkologie, Krankenhaus der Barmherzigen Schwestern, Linz (Austria))

    1994-04-01

    In the breast conserving management of mammary cancer a high-dose-rate (HDR)-Iridium-192 source is used for interstitial boosting of the primary tumor site after external radiotherapy. We want to show the clinical results and side effects and to demonstrate the safe use of a HDR source. From December 1984 until November 1988, 154 patients with breast cancer stage T1-2, N0-1 were treated by conservative surgery and radiation. A dose of 45 to 50 Gy was given to the whole breast by external radiotherapy, and the previous tumor area was boosted by an interstitial implant with Iridium-192 HDR. We applied 10 Gy in one or two fractions. The mean follow-up period of survivors is 76 months (range 57 to 107 months). In 36 patients failures occured: eight patients (5%) developed local recurrences, 31 patients (20%) had distant metastases, and 19 (12%) died with cancer. The Kaplan-Meier estimation for five year overall survival is 86.9%, for disease-specific survival 89.3%, for local control 95.8%, and for disease free survival 80.1%. The most frequent late effects were telangiectasia (11%), fibrotic masses in the previous tumor area (6.5%), and lymphedema of the arm (6.5%). No serious complications could be observed. (orig./MG)

  3. Breast conservation therapy utilizing partial breast brachytherapy for early-stage cancer of the breast: a retrospective review from the Saint Luke's Cancer Institute.

    Science.gov (United States)

    Edwards, Jason M; Herzberg, Susan M; Shook, John W; Beirne, Tammy K N; Schomas, David A

    2015-04-01

    Accelerated partial breast irradiation (APBI) is a convenient alternative to whole-breast irradiation, as less overall time is needed for completion. The use of APBI outside the framework of large prospective clinical trials has markedly increased. To our knowledge, no high-volume, community-based breast program has published their experience with APBI. The records of 93 consecutive patients who underwent APBI utilizing Mammosite Radiation Therapy System from 2005 to 2010 at Saint Luke's Cancer Institute in Kansas City, MO, were retrospectively reviewed. The Kaplan-Meier method was used to estimate the ipsilateral breast recurrence rate and recurrence-free survival. Median age at diagnosis was 63 years (range, 45 to 86 y) and mean follow-up was 29 months. Patient stratification ASTRO consensus classifications for APBI was 37% suitable, 57% cautionary, and 6% unsuitable. The 3-year breast control rate was 98.7%. Three-year overall recurrence-free survival was 94.4%, and 3-year mastectomy-free survival was 97.4%. Using univariate analysis, no tumor or patient factors were associated with ipsilateral breast recurrence. However, tumor grade (P<0.05), stage (P=0.04), estrogen receptor status (P<0.001), progesterone receptor status (P<0.001), tumor size (P<0.001), and ASTRO suitability criteria (P=0.027) were associated with overall recurrence-free survival. No differences were observed when outcomes of patients with ductal carcinoma in situ were compared with those with invasive disease. In our high-volume community-based program, APBI outcomes are comparable with those reported from large academic institutions. We also found relationships between tumor stage, grade, negative estrogen receptor status, and ASTRO suitability criteria with overall recurrence rates. The continued careful application of APBI in appropriately selected patients appears warranted until phase III trials comparing this modality to whole-breast irradiation have matured.

  4. Long-Term Cancer Outcomes From Study NRG Oncology/RTOG 9517: A Phase 2 Study of Accelerated Partial Breast Irradiation With Multicatheter Brachytherapy After Lumpectomy for Early-Stage Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    White, Julia, E-mail: Julia.White@osumc.edu [Department of Radiation Oncology, The James, Ohio State University, Columbus, Ohio (United States); Winter, Kathryn [NRG Oncology Statistics and Data Management Center, Philadelphia, Pennsylvania (United States); Kuske, Robert R. [Department of Radiation Oncology, Arizona Breast Cancer Specialists, Scottsdale, Arizona (United States); Bolton, John S. [Department of Radiation Oncology, Oschner Clinic, New Orleans, Louisiana (United States); Arthur, Douglas W. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia (United States); Scroggins, Troy [Department of Radiation Oncology, Oschner Clinic, New Orleans, Louisiana (United States); Rabinovitch, Rachel A. [Department of Radiation Oncology, University of Colorado Denver, Aurora, Colorado (United States); Kelly, Tracy [Department of Radiation Oncology, Medical College of Wisconsin, Milwaukee, Wisconsin (United States); Toonkel, Leonard M. [Mount Sinai Comprehensive Cancer Center, Miami, Florida (United States); Vicini, Frank A. [Department of Radiation Oncology, Botsford Hospital, Farmington Hills, Michigan (United States); McCormick, Beryl [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2016-08-01

    Purpose: To examine 10-year rates of local, regional, and distant recurrences, patterns of recurrence, and survival rates for breast cancer patients enrolled on Study NRG Oncology/Radiation Therapy Oncology Group 9517, a multi-institutional prospective trial that studied one of the earliest methods of accelerated partial breast irradiation (APBI), multicatheter brachytherapy (MCT). Methods and Materials: Eligibility included stage I/II unifocal breast cancer <3 cm in size after lumpectomy with negative surgical margins and 0 to 3 positive axillary nodes without extracapsular extension. The APBI dose delivered was 34 Gy in 10 twice-daily fractions over 5 days for high-dose-rate (HDR); and 45 Gy in 3.5 to 5 days for low-dose-rate (LDR) brachytherapy. The primary endpoint was HDR and LDR MCT reproducibility. This analysis focuses on long-term ipsilateral breast recurrence (IBR), contralateral breast cancer events (CBE), regional recurrence (RR), and distant metastases (DM), disease-free, and overall survival. Results: The median follow-up was 12.1 years. One hundred patients were accrued from 1997 to 2000; 98 were evaluable; 65 underwent HDR and 33 LDR MCT. Median age was 62 years; 88% had T1 tumors; 81% were pN0. Seventy-seven percent were estrogen receptor and/or progesterone receptor positive; 33% received adjuvant chemotherapy and 64% antiendocrine therapy. There have been 4 isolated IBRs and 1 IBR with RR, for 5.2% 10-year IBR without DM. There was 1 isolated RR, 1 with IBR, and 1 with a CBE, for 3.1% 10-year RR without DM. The 10-year CBE rate was 4.2%, with 5 total events. Eleven patients have developed DM, 8 have died of breast cancer, and 22 have died from other causes. The 10-year DFS and OS rates are 69.8% and 78.0%, respectively. Conclusion: This multi-institutional, phase 2 trial studying MCT-APBI continues to report durable in-breast cancer control rates with long-term follow-up.

  5. A Novel Form of Breast Intraoperative Radiation Therapy With CT-Guided High-Dose-Rate Brachytherapy: Results of a Prospective Phase 1 Clinical Trial

    Energy Technology Data Exchange (ETDEWEB)

    Showalter, Shayna L., E-mail: snl2t@virginia.edu [Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Petroni, Gina [Division of Translation Research and Applied Statistics, Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Trifiletti, Daniel M.; Libby, Bruce [Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Schroen, Anneke T.; Brenin, David R. [Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Dalal, Parchayi [Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Smolkin, Mark [Division of Translation Research and Applied Statistics, Department of Public Health Sciences, University of Virginia School of Medicine, Charlottesville, Virginia (United States); Reardon, Kelli A.; Showalter, Timothy N. [Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, Virginia (United States)

    2016-09-01

    Purpose: Existing intraoperative radiation therapy (IORT) techniques are criticized for the lack of image guided treatment planning and energy deposition with, at times, poor resultant dosimetry and low radiation dose. We pioneered a novel method of IORT that incorporates customized, computed tomography (CT)-based treatment planning and high-dose-rate (HDR) brachytherapy to overcome these drawbacks: CT-HDR-IORT. Methods and Materials: A phase 1 study was conducted to demonstrate the feasibility and safety of CT-HDR-IORT. Eligibility criteria included age ≥50 years, invasive or in situ breast cancer, tumor size <3 cm, and N0 disease. Patients were eligible before or within 30 days of breast-conserving surgery (BCS). BCS was performed, and a multilumen balloon catheter was placed. CT images were obtained, a customized HDR brachytherapy plan was created, and a dose of 12.5 Gy was delivered to 1-cm depth from the balloon surface. The catheter was removed, and the skin was closed. The primary endpoints were feasibility and acute toxicity. Feasibility was defined as IORT treatment interval (time from CT acquisition until IORT completion) ≤90 minutes. The secondary endpoints included dosimetry, cosmetic outcome, quality of life, and late toxicity. Results: Twenty-eight patients were enrolled. The 6-month follow-up assessments were completed by 93% of enrollees. The median IORT treatment interval was 67.2 minutes (range, 50-108 minutes). The treatment met feasibility criteria in 26 women (93%). The dosimetric goals were met in 22 patients (79%). There were no Radiation Therapy Oncology Group grade 3+ toxicities; 6 patients (21%) experienced grade 2 events. Most patients (93%) had good/excellent cosmetic outcomes at the last follow-up visit. Conclusions: CT-HDR-IORT is feasible and safe. This promising approach for a conformal, image-based, higher-dose breast IORT is being evaluated in a phase 2 trial.

  6. Intratumorally Injected 177Lu-Labeled Gold Nanoparticles: Gold Nanoseed Brachytherapy with Application for Neoadjuvant Treatment of Locally Advanced Breast Cancer.

    Science.gov (United States)

    Yook, Simmyung; Cai, Zhongli; Lu, Yijie; Winnik, Mitchell A; Pignol, Jean-Philippe; Reilly, Raymond M

    2016-06-01

    Improvements in the treatment of locally advanced breast cancer (LABC) are needed. Our objective was to study a radiation nanomedicine (gold nanoseeds) composed of 30-nm gold nanoparticles (AuNP) modified with polyethyleneglycol (PEG) chains linked to DOTA for complexing the β-particle emitter (177)Lu and to panitumumab for targeting epidermal growth factor receptors (EGFR) ((177)Lu-T-AuNP) as a novel neoadjuvant brachytherapy for LABC. Nontargeted gold nanoseeds ((177)Lu-NT-AuNP) were constructed without panitumumab for comparison. (177)Lu-T-AuNP or (177)Lu-NT-AuNP was injected intratumorally in CD-1 athymic mice bearing subcutaneous EGFR-positive MDA-MB-468 human breast cancer tumors. Biodistribution and small-animal SPECT/CT imaging studies were performed to evaluate tumor and normal organ localization. A short-term (15 d) study was conducted to select the most effective amount of (177)Lu-T-AuNP or (177)Lu-NT-AuNP for treatment with long-term observation (90-120 d). Normal organ toxicities were assessed by monitoring body weight, blood cell counts, and serum alanine aminotransferase and creatinine. Radiation-absorbed doses in the tumor and normal organs were estimated by Monte Carlo N-Particle version 5.0 modeling. Tumor radioactivity concentrations were high at 1 h after injection (>300-400 percentage injected dose per gram [%ID/g]) but decreased by 2-3-fold at 48 h after injection. Normal organ uptake was low (tumor growth over 90 d without normal organ toxicity, whereas tumors continued to grow in mice treated with unlabeled T-AuNP or (177)Lu-labeled PEG polymer not linked to AuNP. Survival was prolonged up to 120 d in mice treated with (177)Lu-T-AuNP or (177)Lu-NT-AuNP. Radiation-absorbed doses to the tumor were 30 and 22 Gy for (177)Lu-T-AuNP and (177)Lu-NT-AuNP, respectively. Some tumor regions received high radiation doses (250-1,300 Gy). Normal organ doses were low (0.04-0.6 Gy). Gold nanoseeds injected intratumorally were highly effective for

  7. MRI-guided single fraction ablative radiotherapy for early-stage breast cancer: a brachytherapy versus volumetric modulated arc therapy dosimetry study.

    Science.gov (United States)

    Charaghvandi, Ramona K; den Hartogh, Mariska D; van Ommen, Anne-Mar L N; de Vries, Wilfred J H; Scholten, Vincent; Moerland, Marinus A; Philippens, Mariëlle E P; Schokker, Rogier I; van Vulpen, Marco; van Asselen, Bram; van den Bongard, Desirée H J G

    2015-12-01

    A radiosurgical treatment approach for early-stage breast cancer has the potential to minimize the patient's treatment burden. The dosimetric feasibility for single fraction ablative radiotherapy was evaluated by comparing volumetric modulated arc therapy (VMAT) with an interstitial multicatheter brachytherapy (IMB) approach. The tumors of 20 patients with early-stage breast cancer were delineated on a preoperative contrast-enhanced planning CT-scan, co-registered with a contrast-enhanced magnetic resonance imaging (MRI), both in radiotherapy supine position. A dose of 15 Gy was prescribed to the planned target volume of the clinical target volume (PTVCTV), and 20 Gy integrated boost to the PTV of the gross tumor volume (PTVGTV). Treatment plans for IMB and VMAT were optimized for adequate target volume coverage and minimal organs at risk (OAR) dose. The median PTVGTV/CTV receiving at least 95% of the prescribed dose was ⩾99% with both techniques. The median PTVCTV unintentionally receiving 95% of the prescribed PTVGTV dose was 65.4% and 4.3% with IMB and VMAT, respectively. OAR doses were comparable with both techniques. MRI-guided single fraction radiotherapy with an integrated ablative boost to the GTV is dosimetrically feasible with both techniques. We perceive IMB less suitable for clinical implementation due to PTVCTV overdosage. Future studies have to confirm the clinical feasibility of the single fraction ablative approach. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. External beam boost versus interstitial high-dose-rate brachytherapy boost in the adjuvant radiotherapy following breast-conserving therapy in early-stage breast cancer: a dosimetric comparison

    Science.gov (United States)

    Melchert, Corinna; Kovács, György

    2016-01-01

    Purpose This study aims to compare the dosimetric data of local tumor's bed dose escalation (boost) with photon beams (external beam radiation therapy – EBRT) versus high-dose-rate interstitial brachytherapy (HDR-BT) after breast-conserving treatment in women with early-stage breast cancer. Material and methods We analyzed the treatment planning data of 136 irradiated patients, treated between 2006 and 2013, who underwent breast-conserving surgery and adjuvant whole breast irradiation (WBI; 50.4 Gy) and boost (HDR-BT: 10 Gy in one fraction [n = 36]; EBRT: 10 Gy in five fractions [n = 100]). Organs at risk (OAR; heart, ipsilateral lung, skin, most exposed rib segment) were delineated. Dosimetric parameters were calculated with the aid of dose-volume histograms (DVH). A non-parametric test was performed to compare the two different boost forms. Results There was no difference for left-sided cancers regarding the maximum dose to the heart (HDR-BT 29.8% vs. EBRT 29.95%, p = 0.34). The maximum doses to the other OAR were significantly lower for HDR-BT (Dmax lung 47.12% vs. 87.7%, p skin 57.1% vs. 94.75%, p < 0.01; in the case of right-sided breast irradiation, dose of the heart 6.00% vs. 16.75%, p < 0.01). Conclusions Compared to EBRT, local dose escalation with HDR-BT presented a significant dose reduction to the investigated OAR. Only left-sided irradiation showed no difference regarding the maximum dose to the heart. Reducing irradiation exposure to OAR could result in a reduction of long-term side effects. Therefore, from a dosimetric point of view, an interstitial boost complementary to WBI via EBRT seems to be more advantageous in the adjuvant radiotherapy of breast cancer. PMID:27648082

  9. External beam boost versus interstitial high-dose-rate brachytherapy boost in the adjuvant radiotherapy following breast-conserving therapy in early-stage breast cancer: a dosimetric comparison

    Directory of Open Access Journals (Sweden)

    Martje Marie Terheyden

    2016-08-01

    Full Text Available Purpose : This study aims to compare the dosimetric data of local tumor’s bed dose escalation (boost with photon beams (external beam radiation therapy – EBRT versus high-dose-rate interstitial brachytherapy (HDR-BT after breast-conserving treatment in women with early-stage breast cancer. Material and methods : We analyzed the treatment planning data of 136 irradiated patients, treated between 2006 and 2013, who underwent breast-conserving surgery and adjuvant whole breast irradiation (WBI; 50.4 Gy and boost (HDR-BT: 10 Gy in one fraction [n = 36]; EBRT: 10 Gy in five fractions [n = 100]. Organs at risk (OAR; heart, ipsilateral lung, skin, most exposed rib segment were delineated. Dosimetric parameters were calculated with the aid of dose-volume histograms (DVH. A non-parametric test was performed to compare the two different boost forms. Results : There was no difference for left-sided cancers regarding the maximum dose to the heart (HDR-BT 29.8% vs. EBRT 29.95%, p = 0.34. The maximum doses to the other OAR were significantly lower for HDR-BT (Dmax lung 47.12% vs. 87.7%, p < 0.01; rib 61.17% vs. 98.5%, p < 0.01; skin 57.1% vs. 94.75%, p < 0.01; in the case of right-sided breast irradiation, dose of the heart 6.00% vs. 16.75%, p < 0.01. Conclusions : Compared to EBRT, local dose escalation with HDR-BT presented a significant dose reduction to the investigated OAR. Only left-sided irradiation showed no difference regarding the maximum dose to the heart. Reducing irradiation exposure to OAR could result in a reduction of long-term side effects. Therefore, from a dosimetric point of view, an interstitial boost complementary to WBI via EBRT seems to be more advantageous in the adjuvant radiotherapy of breast cancer.

  10. Multicatheter interstitial brachytherapy versus intensity modulated external beam therapy for accelerated partial breast irradiation: A comparative treatment planning study with respect to dosimetry of organs at risk.

    Science.gov (United States)

    Major, Tibor; Stelczer, Gábor; Pesznyák, Csilla; Mészáros, Norbert; Polgár, Csaba

    2017-01-01

    To dosimetrically compare multicatheter interstitial brachytherapy (MIBT) and intensity modulated radiotherapy (IMRT) for accelerated partial breast irradiation (APBI) with special focus on dose to normal tissues and organs at risk (OAR-s). Thirty-four patients with early stage breast cancer treated with MIBT were selected for the study. For each patient an additional IMRT treatment plan was created using the same CT data and contours as used in MIBT plans. OAR-s included ipsilateral non-target and contralateral breast, lung of both sides, skin, ribs and heart for left sided lesions. The CTV was created from the outlined lumpectomy cavity with a total margin (surgical+radiation) of 20mm in six main directions. The PTV in IMRT plans was generated from CTV with an addition of isotropic 5mm margin. The prescribed dose was 30.1Gy with 7×4.3Gy fractionation for both techniques. From dose-volume histograms quality parameters including volumes receiving a given dose (e.g. V100, V90, V50) and doses to specified volumes (e.g. D0.01cm(3), D0.1cm(3), D1cm(3)) were calculated and compared. Except for high dose, non-target breast received less dose with MIBT. V90 was 3.6% vs. 4.8% and V50 was 13.7% vs. 25.5% for MIBT and IMRT, respectively. Ipsilateral lung was spared better with MIBT. Mean lung dose was 5.1% vs. 7.1%, [Formula: see text] was 39.0% vs. 54.3% and V5 was 32.9% vs. 41.7% in favour of MIBT. For left sided lesions the heart was generally irradiated by larger doses with MIBT. Mean heart dose was 4.5% vs. 2.0% and [Formula: see text] was 18.3% vs. 19.7%, correspondingly. Volumetric maximal skin doses were similar, but regarding dose to 0.1cm(3) and 1cm(3) of most exposed volume MIBT provided significantly less doses (76.6% vs. 94.4% and 60.2% vs. 87.8%, respectively). Ribs received less dose with MIBT with values of 45.6% vs. 69.3% for [Formula: see text] and 1.4% vs. 4.2cm(3) for V50. Dose to contralateral breast and lung was low with both techniques. No significant

  11. High dose rate brachytherapy for oral cancer

    Science.gov (United States)

    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

  12. Deep Nonlinear Metric Learning for 3-D Shape Retrieval.

    Science.gov (United States)

    Xie, Jin; Dai, Guoxian; Zhu, Fan; Shao, Ling; Fang, Yi

    2018-01-01

    Effective 3-D shape retrieval is an important problem in 3-D shape analysis. Recently, feature learning-based shape retrieval methods have been widely studied, where the distance metrics between 3-D shape descriptors are usually hand-crafted. In this paper, motivated by the fact that deep neural network has the good ability to model nonlinearity, we propose to learn an effective nonlinear distance metric between 3-D shape descriptors for retrieval. First, the locality-constrained linear coding method is employed to encode each vertex on the shape and the encoding coefficient histogram is formed as the global 3-D shape descriptor to represent the shape. Then, a novel deep metric network is proposed to learn a nonlinear transformation to map the 3-D shape descriptors to a nonlinear feature space. The proposed deep metric network minimizes a discriminative loss function that can enforce the similarity between a pair of samples from the same class to be small and the similarity between a pair of samples from different classes to be large. Finally, the distance between the outputs of the metric network is used as the similarity for shape retrieval. The proposed method is evaluated on the McGill, SHREC'10 ShapeGoogle, and SHREC'14 Human shape datasets. Experimental results on the three datasets validate the effectiveness of the proposed method.

  13. Comparison of organ doses for patients undergoing balloon brachytherapy of the breast with HDR {sup 192}Ir or electronic sources using Monte Carlo simulations in a heterogeneous human phantom

    Energy Technology Data Exchange (ETDEWEB)

    Mille, Matthew M.; Xu, X. George; Rivard, Mark J. [Nuclear Engineering and Engineering Physics Program, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

    2010-02-15

    Purpose: Accelerated partial breast irradiation via interstitial balloon brachytherapy is a fast and effective treatment method for certain early stage breast cancers. The radiation can be delivered using a conventional high-dose rate (HDR) {sup 192}Ir gamma-emitting source or a novel electronic brachytherapy (eBx) source which uses lower energy x rays that do not penetrate as far within the patient. A previous study [A. Dickler, M. C. Kirk, N. Seif, K. Griem, K. Dowlatshahi, D. Francescatti, and R. A. Abrams, ''A dosimetric comparison of MammoSite high-dose-rate brachytherapy and Xoft Axxent electronic brachytherapy,'' Brachytherapy 6, 164-168 (2007)] showed that the target dose is similar for HDR {sup 192}Ir and eBx. This study compares these sources based on the dose received by healthy organs and tissues away from the treatment site. Methods: A virtual patient with left breast cancer was represented by a whole-body, tissue-heterogeneous female voxel phantom. Monte Carlo methods were used to calculate the dose to healthy organs in a virtual patient undergoing balloon brachytherapy of the left breast with HDR {sup 192}Ir or eBx sources. The dose-volume histograms for a few organs which received large doses were also calculated. Additional simulations were performed with all tissues in the phantom defined as water to study the effect of tissue inhomogeneities. Results: For both HDR {sup 192}Ir and eBx, the largest mean organ doses were received by the ribs, thymus gland, left lung, heart, and sternum which were close to the brachytherapy source in the left breast. eBx yielded mean healthy organ doses that were more than a factor of {approx}1.4 smaller than for HDR {sup 192}Ir for all organs considered, except for the three closest ribs. Excluding these ribs, the average and median dose-reduction factors were {approx}28 and {approx}11, respectively. The volume distribution of doses in nearby soft tissue organs that were outside the PTV were also

  14. Comprehensive brachytherapy physical and clinical aspects

    CERN Document Server

    Baltas, Dimos; Meigooni, Ali S; Hoskin, Peter J

    2013-01-01

    Modern brachytherapy is one of the most important oncological treatment modalities requiring an integrated approach that utilizes new technologies, advanced clinical imaging facilities, and a thorough understanding of the radiobiological effects on different tissues, the principles of physics, dosimetry techniques and protocols, and clinical expertise. A complete overview of the field, Comprehensive Brachytherapy: Physical and Clinical Aspects is a landmark publication, presenting a detailed account of the underlying physics, design, and implementation of the techniques, along with practical guidance for practitioners. Bridging the gap between research and application, this single source brings together the technological basis, radiation dosimetry, quality assurance, and fundamentals of brachytherapy. In addition, it presents discussion of the most recent clinical practice in brachytherapy including prostate, gynecology, breast, and other clinical treatment sites. Along with exploring new clinical protocols, ...

  15. NOTE: Clinical application of a OneDose™ MOSFET for skin dose measurements during internal mammary chain irradiation with high dose rate brachytherapy in carcinoma of the breast

    Science.gov (United States)

    Kinhikar, Rajesh A.; Sharma, Pramod K.; Tambe, Chandrashekhar M.; Mahantshetty, Umesh M.; Sarin, Rajiv; Deshpande, Deepak D.; Shrivastava, Shyam K.

    2006-07-01

    In our earlier study, we experimentally evaluated the characteristics of a newly designed metal oxide semiconductor field effect transistor (MOSFET) OneDose™ in-vivo dosimetry system for Ir-192 (380 keV) energy and the results were compared with thermoluminescent dosimeters (TLDs). We have now extended the same study to the clinical application of this MOSFET as an in-vivo dosimetry system. The MOSFET was used during high dose rate brachytherapy (HDRBT) of internal mammary chain (IMC) irradiation for a carcinoma of the breast. The aim of this study was to measure the skin dose during IMC irradiation with a MOSFET and a TLD and compare it with the calculated dose with a treatment planning system (TPS). The skin dose was measured for ten patients. All the patients' treatment was planned on a PLATO treatment planning system. TLD measurements were performed to compare the accuracy of the measured results from the MOSFET. The mean doses measured with the MOSFET and the TLD were identical (0.5392 Gy, 15.85% of the prescribed dose). The mean dose was overestimated by the TPS and was 0.5923 Gy (17.42% of the prescribed dose). The TPS overestimated the skin dose by 9% as verified by the MOSFET and TLD. The MOSFET provides adequate in-vivo dosimetry for HDRBT. Immediate readout after irradiation, small size, permanent storage of dose and ease of use make the MOSFET a viable alternative for TLDs.

  16. Clinical application of a OneDose MOSFET for skin dose measurements during internal mammary chain irradiation with high dose rate brachytherapy in carcinoma of the breast.

    Science.gov (United States)

    Kinhikar, Rajesh A; Sharma, Pramod K; Tambe, Chandrashekhar M; Mahantshetty, Umesh M; Sarin, Rajiv; Deshpande, Deepak D; Shrivastava, Shyam K

    2006-07-21

    In our earlier study, we experimentally evaluated the characteristics of a newly designed metal oxide semiconductor field effect transistor (MOSFET) OneDose in-vivo dosimetry system for Ir-192 (380 keV) energy and the results were compared with thermoluminescent dosimeters (TLDs). We have now extended the same study to the clinical application of this MOSFET as an in-vivo dosimetry system. The MOSFET was used during high dose rate brachytherapy (HDRBT) of internal mammary chain (IMC) irradiation for a carcinoma of the breast. The aim of this study was to measure the skin dose during IMC irradiation with a MOSFET and a TLD and compare it with the calculated dose with a treatment planning system (TPS). The skin dose was measured for ten patients. All the patients' treatment was planned on a PLATO treatment planning system. TLD measurements were performed to compare the accuracy of the measured results from the MOSFET. The mean doses measured with the MOSFET and the TLD were identical (0.5392 Gy, 15.85% of the prescribed dose). The mean dose was overestimated by the TPS and was 0.5923 Gy (17.42% of the prescribed dose). The TPS overestimated the skin dose by 9% as verified by the MOSFET and TLD. The MOSFET provides adequate in-vivo dosimetry for HDRBT. Immediate readout after irradiation, small size, permanent storage of dose and ease of use make the MOSFET a viable alternative for TLDs.

  17. Dosimetric Improvements in Balloon Based Brachytherapy Using the Contura® Multi-Lumen Balloon (MLB Catheter to Deliver Accelerated Partial Breast Irradiation

    Directory of Open Access Journals (Sweden)

    Thomas Julian

    2010-04-01

    Full Text Available Purpose: Preliminary dosimetric findings in patients managed with the Contura® Multi-Lumen Balloon (MLB breast brachytherapy catheter to deliver accelerated partial breast irradiation (APBI on a multi-institutional phase IV registry trial were reviewed. Material and methods: CT-based 3D planning with dose optimization was performed for all patients. For the study, new ideal dosimetric goals were developed: 1 ≥ 95% of the prescribed dose (PD covering ≥ 90% of the target volume (TV, 2 a maximum skin dose ≤ 125% of the PD, 3 maximum rib dose ≤ 145% of the PD, and 4 the V150 ≤ 50 cc and V200 ≤ 10 cc. The frequency of concurrently achieving these dosimetric goals using the Contura® MLB was investigated.Results: 194 cases were evaluable. Employing the MLB, all ideal dosimetric criteria were achieved in 76% of cases.Evaluating dosimetric criteria separately, 90% and 89% of cases met the new ideal skin and rib dose criteria, respectively. In 96%, ideal TV coverage goals were achieved and in 96%, dose homogeneity criteria (V150 and V200 were met. For skin spacing ≥ 5-7 mm, the median skin dose was 121% of the PD and when < 5 mm, the median skin dose was 124.4%. For rib distancees < 5 mm, the median rib dose was reduced to 136.4% of the PD. For skin spacing < 7 mm and distance to rib < 5 mm, the median skin and rib doses were concurrently limited to 121% and 142.8% of thePD, respectively. Conclusions: The Contura® MLB catheter provides potential improvements in dosimetric capabilities (i.e., reduced skin and rib doses and improved TV coverage in many clinical scenarios.

  18. Electron and high-dose-rate brachytherapy boost in the conservative treatment of stage I-II breast cancer. First results of the randomized Budapest boost trial

    Energy Technology Data Exchange (ETDEWEB)

    Polgar, C.; Fodor, J. [National Institute of Oncology, Department of Radiotherapy, Budapest (Hungary); Orosz, Z. [National Institute of Oncology, Center of Experimental and Human Tumor Pathology Budapest (HU)] [and others

    2002-11-01

    Background and Aims: To evaluate the effect of electron and high-dose-rate brachytherapy (HDR BT) boost on local tumor control (LTC), side effects and cosmesis after breast-conserving surgery (BCS) in a prospective randomized study. Patients and Methods: 207 women with stage I-II breast cancer who underwent BCS were treated by 50 Gy irradiation to the whole breast and then randomly assigned to receive either a boost to the tumor bed (n=104) or no further radiotherapy (n=103). Boost treatments consisted of either 16 Gy electron irradiation (n=52) or 12-14.25 Gy HDR BT (n=52). Breast cancer-related events, side effects, and cosmetic results were assessed. Results: At a median follow-up of 5.3 years, the crude rate of local recurrence was 6.7% (7/104) with and 15.5% (16/103) without boost. The 5-year probability of LTC, relapse-free survival (RFS), and cancer-specific survival (CSS) was 92.7% vs 84.9% (p=0.049), 76.6% vs 66.2% (p=0.044), and 90.4% vs. 82.1% (p=0.053), respectively. There was no significant difference in LTC between patients treated with electron or HDR BT boost (94.2% vs 91.4%; p=0.74). On multivariate analysis, patient age <40 years (RR: 4.53), positive margin status (RR: 4.17), and high mitotic activity index (RR: 3.60) were found to be significant risk factors for local recurrence. The incidence of grade 2-3 side effects was higher in the boost arm (17.3% vs 7.8%; p=0.03). However, the rate of excellent/good cosmetic results was similar for the two arms (85.6% vs 91.3%; p=0.14). Cosmesis was rated as excellent/good in 88.5% of patients treated with HDR BT and 82.7% of patients with electron boost (p=0.29). Conclusions: Boost dose significantly improves LTC and RFS in patients treated with BCS and radiotherapy. In spite of the higher incidence of late side effects in the boost arm, boost dose is strongly recommended for patients at high risk for local recurrence. Positive or close margin status, high mitotic activity index, and young patient age

  19. SU-E-T-548: Modeling of Breast IORT Using the Xoft 50 KV Brachytherapy Source and 316L Steel Rigid Shield

    Energy Technology Data Exchange (ETDEWEB)

    Burnside, W [Mountain View, CA (United States)

    2015-06-15

    Purpose: Xoft provides a set of 316L Stainless Steel Rigid Shields to be used with their 50 kV X-ray source for Breast IORT treatments. Modeling the different shield sizes in MCNP provides information to help make clinical decisions for selecting the appropriate shield size. Methods: The Xoft Axxent 50 kV Electronic Brachytherapy System has several applications in radiation therapy, one of which is treating cancer of the breast intraoperatively by placing the miniaturized X-ray tube inside an applicator balloon that is expanded to fill the lumpectomy bed immediately following tumor removal. The ribs, lung, and muscular chest wall are all regions at risk to receive undesired dose during the treatment. A Xoft 316L Stainless Steel Rigid Shield can be placed between the intracostal muscles of the chest wall and the remaining breast tissue near the balloon to attenuate the beam and protect these organs. These shields are provided in 5 different sizes, and the effects on dose to the surrounding tissues vary with shield size. MCNP was used to model this environment and tally dose rate to certain regions of interest. Results: The average rib dose rate calculated using 0cm (i.e., no shield), 3cm, and 5cm diameter shields were 26.89, 15.43, and 8.91 Gy/hr respectively. The maximum dose rates within the rib reached 94.74 Gy/hr, 53.56 Gy/hr, and 31.44 Gy/hr for the 0cm, 3cm, and 5cm cases respectively. The shadowing effect caused by the steel shields was seen in the 3-D meshes and line profiles. Conclusion: This model predicts a higher dose rate to the underlying rib region with the 3cm shield compared to the 5cm shield; it may be useful to select the largest possible diameter when choosing a shield size for a particular IORT patient. The ability to attenuate the beam to reduce rib dose was also confirmed. Research sponsored by Xoft Inc, a subsidiary of iCAD.

  20. Brachytherapy catheter spacing and stabilization technique.

    Science.gov (United States)

    Demanes, D Jeffrey; Friedman, Jeffrey M; Park, Sang-June; Steinberg, Michael L; Hayes, John K; Kamrava, Mitchell R

    2012-01-01

    To facilitate catheter spacing, implant stability, and patient comfort during multicatheter interstitial brachytherapy. Uniform and consistent spacing of multiple interstitial implant catheters can be difficult because individual catheters may become displaced during the course of treatment. The authors have developed a brachytherapy catheter fixation method using Jackson-Pratt (JP) drains that can be used within wounds to maintain catheter spacing or on the skin surface for applicator fixation. JP drains are threaded over the implant needles to space and stabilize the implant geometry. The needles are then replaced with the usual brachytherapy catheters. Surgically directed ("open") placement of implant catheters is less prone to displacement when a drain connects and spaces the catheters in the wound. Fixation on the skin surface can also be achieved with the JP drains, which make the friction buttons optional. The soft drain material helps avoid discomfort and pressure injury sometimes associated with hard plastic buttons. Small (10 French) round JP drains are suitable for breast, and head and neck sites and larger 7×10-mm flat JP drains for extremity sarcomas, abdominal, or thoracic tumors. The complex brachytherapy devices fashioned from widely available surgical drains effectively guide and maintain geometry for multicatheter interstitial implants. Stable implant geometry leads to more reliable implementation of brachytherapy dosimetry. Patient comfort is improved and soft tissue injury from hard-edged buttons is avoided. Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  1. A radiobiological investigation on dose and dose rate for permanent implant brachytherapy of breast using I125 or P103d sources.

    Science.gov (United States)

    Baltas, Dimos; Lymperopoulou, Georgia; Löffler, Edgar; Mavroidis, Panayiotis

    2010-06-01

    The present report addresses the question of what could be the appropriate dose and dose rate for I125 and P103d permanent seed implants for breast cancer as monotherapy for early stage breast cancer. This is addressed by employing a radiobiological methodology, which is based on the linear quadratic model, to identify a biologically effective dose (BED) to the prescription point of the brachytherapy implant, which would produce equivalent cell killing (or same cell survival) when compared to a specified external radiotherapy scheme. In the present analysis, the tumor and normal tissue BED ratios of brachytherapy and external radiotherapy are examined for different combinations of tumor proliferation constant (K), α/β ratios, initial dose rate (R0), and reference external radiotherapy scheme (50 or 60 Gy in 2 Gy per fraction). The results of the radiobiological analysis are compared against other reports and clinical protocols in order to examine possible opportunities of improvement. The analysis indicates that physical doses of approximately 100-110 Gy delivered with an initial dose rate of around 0.05Gyh-1 and 78-80 Gy delivered at 0.135Gyh-1 for I125 and P103d permanent implants, respectively, are equivalent to 50 Gy external beam radiotherapy (EBRT) in 2 Gy per fraction. Similarly, for physical doses of approximately 115-127 Gy delivered with an initial dose rate of around 0.059Gyh-1 and 92 Gy delivered at 0.157Gyh-1 for I125 and P103d, respectively, are equivalent to 60 Gy EBRT in 2 Gy per fraction. It is shown that the initial dose rate required to produce isoeffective tumor response with 50 or 60 Gy EBRT in 2 Gy per fraction increases as the repopulation factor K increases, even though repopulation is also considered in EBRT. Also, the initial dose rate increases as the value of the α/β ratio decreases. The impact of the different α/β ratios on the ratio of the tumor BEDs is significantly large for both the I125 and P103d implants with the deviation

  2. Optofluidic fabrication for 3D-shaped particles

    Science.gov (United States)

    Paulsen, Kevin S.; di Carlo, Dino; Chung, Aram J.

    2015-04-01

    Complex three-dimensional (3D)-shaped particles could play unique roles in biotechnology, structural mechanics and self-assembly. Current methods of fabricating 3D-shaped particles such as 3D printing, injection moulding or photolithography are limited because of low-resolution, low-throughput or complicated/expensive procedures. Here, we present a novel method called optofluidic fabrication for the generation of complex 3D-shaped polymer particles based on two coupled processes: inertial flow shaping and ultraviolet (UV) light polymerization. Pillars within fluidic platforms are used to deterministically deform photosensitive precursor fluid streams. The channels are then illuminated with patterned UV light to polymerize the photosensitive fluid, creating particles with multi-scale 3D geometries. The fundamental advantages of optofluidic fabrication include high-resolution, multi-scalability, dynamic tunability, simple operation and great potential for bulk fabrication with full automation. Through different combinations of pillar configurations, flow rates and UV light patterns, an infinite set of 3D-shaped particles is available, and a variety are demonstrated.

  3. The effects of aging on haptic 2D shape recognition

    NARCIS (Netherlands)

    Overvliet, K.E.; Wagemans, J.; Krampe, R.T.

    2013-01-01

    We use the image-mediation model (Klatzky & Lederman, 1987) as a framework to investigate potential sources of adult age differences in the haptic recognition of two-dimensional (2D) shapes. This model states that the low-resolution, temporally sequential, haptic input is translated into a visual

  4. Volume Sculpting: Intuitive, Interactive 3D Shape Modelling

    DEFF Research Database (Denmark)

    Bærentzen, Jakob Andreas

    A system for interactive modelling of 3D shapes on a computer is presented. The system is intuitive and has a flat learning curve. It is especially well suited to the creation of organic shapes and shapes of complex topology. The interaction is simple; the user can either add new shape features...

  5. L1 Generalized Procrustes 2D Shape Alignment

    DEFF Research Database (Denmark)

    Larsen, Rasmus; Eiriksson, Hrafnkell

    2002-01-01

    We describe a new method for resistant and robust alignment of sets of 2D shapes wrt. position, rotation, and isotropical scaling based on minimization of absolute distances. The shapes are represented by \\$k\\$ landmarks in two dimensions. It is formulated as a linear programming (LP) problem, th...

  6. SU-E-T-580: On the Significance of Model Based Dosimetry for Breast and Head and Neck 192Ir HDR Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Peppa, V; Pappas, E; Pantelis, E; Papagiannis, P [Medical Physics Laboratory, Medical School, University of Athens, Athens (Greece); Major, T; Polgar, C [National Institute of Oncology, Budapest (Hungary)

    2015-06-15

    Purpose: To assess the dosimetric and radiobiological differences between TG43-based and model-based dosimetry in the treatment planning of {sup 192}Ir HDR brachytherapy for breast and head and neck cancer. Methods: Two cohorts of 57 Accelerated Partial Breast Irradiation (APBI) and 22 head and neck (H&N) patients with oral cavity carcinoma were studied. Dosimetry for the treatment plans was performed using the TG43 algorithm of the Oncentra Brachy v4.4 treatment planning system (TPS). Corresponding Monte Carlo (MC) simulations were performed using MCNP6 with input files automatically prepared by the BrachyGuide software tool from DICOM RT plan data. TG43 and MC data were compared in terms of % dose differences, Dose Volume Histograms (DVHs) and related indices of clinical interest for the Planning Target Volume (PTV) and the Organs-At-Risk (OARs). A radiobiological analysis was also performed using the Equivalent Uniform Dose (EUD), mean survival fraction (S) and Tumor Control Probability (TCP) for the PTV, and the Normal Tissue Control Probability (N TCP) and the generalized EUD (gEUD) for the OARs. Significance testing of the observed differences performed using the Wilcoxon paired sample test. Results: Differences between TG43 and MC DVH indices, associated with the increased corresponding local % dose differences observed, were statistically significant. This is mainly attributed to their consistency however, since TG43 agrees closely with MC for the majority of DVH and radiobiological parameters in both patient cohorts. Differences varied considerably among patients only for the ipsilateral lung and ribs in the APBI cohort, with a strong correlation to target location. Conclusion: While the consistency and magnitude of differences in the majority of clinically relevant DVH indices imply that no change is needed in the treatment planning practice, individualized dosimetry improves accuracy and addresses instances of inter-patient variability observed. Research

  7. Whole breast irradiation vs. APBI using multicatheter brachytherapy in early breast cancer – simulation of treatment costs based on phase 3 trial data

    Directory of Open Access Journals (Sweden)

    Aleksandra Harat

    2016-12-01

    Full Text Available Purpose: A recent large phase 3 trial demonstrated that the efficacy of accelerated partial-breast irradiation (APBI in the treatment of early breast cancer is non-inferior to that of whole breast irradiation (WBI commonly used in this indication. The aim of this study was to compare the costs of treatment with APBI and WBI in a population of patients after conserving surgery for early breast cancer, and to verify if the use of APBI can result in direct savings of a public payer. Material and methods : The hereby presented cost analysis was based on the results of GEC-ESTRO trial. Expenditures for identified cost centers were estimated on the basis of reimbursement data for the public payer. After determining the average cost of early breast cancer treatment with APBI and WBI over a 5-year period, the variance in this parameter resulting from fluctuations in the price per single procedure was examined on univariate sensitivity analysis. Then, incremental cost-effectiveness ratio (ICER was calculated to verify the cost against clinical outcome. Finally, a simulation of public payer’s expenditures for the treatment of early breast cancer with APBI and WBI in 2013 and 2025 has been conducted. Results: The average cost of treatment with APBI is lower than for WBI, even assuming a potential increase in the unit price of the former procedure. There was no additional health benefit of WBI and the calculation of cost-effectiveness was based on the absolute difference in overall local control rate. However, this difference (0.92% vs. 1.44% was fairly minimal and was not identified as statistically significant during 5 years. Conclusions : The use of APBI as an alternative to WBI in the treatment of early breast cancer would substantially reduce healthcare expenditures in both 2013 and 2025, even assuming an increase in the price per single APBI procedure.

  8. Partial breast irradiation: high dose rate per-operative brachytherapy technique using the MammoSite; Irradiation partielle du sein: technique de curietherapie de haut debit de dose apres l'implantation peroperatoire du dispositif MammoSite

    Energy Technology Data Exchange (ETDEWEB)

    Belkacemi, Y.; Poupon, L.; Castellanos, M.E.; Villette, S.; Lartigau, E. [Centre de Lutte Contre le Cancer Oscar-Lambret, Dept. de Radiotherapie, 59 - Lille (France); Chauvet, M.P.; Giard, S. [Centre de Lutte Contre le Cancer Oscar-Lambret, Dept. de Chirurgie Senologique, 59 - Lille (France); Bonodeau, F. [de Lutte Contre le Cancer Oscar-Lambret, Dept. de Radiologie, 59 - Lille (France); Cabaret, V. [de Lutte Contre le Cancer Oscar-Lambret, Dept. d' Anatomopathologie, 59 - Lille (France)

    2003-11-01

    In the conservative management of breast cancer, radiation therapy delivering 45 to 50 Gy to the whole breast, in 4.5 to 5 weeks, followed by a booster dose of 10 to 20 Gy is the standard of care. Based on the numerous studies which have reported that the local recurrences occurs within and surrounding the primary tumor site and in order to decrease the treatment duration and its morbidity, partial breast irradiation using several techniques has been developed. Partial irradiation may be considered as an alternative local adjuvant treatment for selected patients with favorable prognostic factors. Using external beam radiation therapy, the 3D-conformal technique is appropriate to deliver the whole dose to a limited volume. In UK, an intraoperative technique using a miniature beam of low energy of X-ray (50 kV) has been developed (Targit). Milan's team have developed an intraoperative electrons beam radiotherapy using a dedicated linear accelerator in the operative room. In USA and Canada the MammoSite has been advised for clinical use in per-operative brachytherapy of the breast. These two last techniques are currently compared in phase III randomized studies to the standard whole breast irradiation followed by a tumour bed booster dose. In this review we will focus on the MammoSite technique and will describe the per-operative implantation procedure. radiological controls ad dosimetric aspects. (author)

  9. RTOG 95-17, a Phase II trial to evaluate brachytherapy as the sole method of radiation therapy for Stage I and II breast carcinoma--year-5 toxicity and cosmesis.

    Science.gov (United States)

    Rabinovitch, Rachel; Winter, Kathryn; Kuske, Robert; Bolton, John; Arthur, Doug; Scroggins, Troy; Vicini, Frank; McCormick, Beryl; White, Julia

    2014-01-01

    Radiation Therapy Oncology Group (RTOG) 95-17, a Phase II trial to evaluate multicatheter brachytherapy (mCathBrachy) as the sole method of radiation therapy for Stage I-II breast cancer (BrCa), was the first cooperative group trial in North America to evaluate accelerated partial breast irradiation (APBI) and include patient-reported outcomes (PROs). This report presents the year-5 toxicity and cosmesis data. After lumpectomy and axillary dissection for invasive BrCa (tumor size skin toxicity developed in 78% of the pts and G3 in 13% (no G4). The tx effects included skin dimpling/indentation (37%), fibrosis (45%), telangiectasias (45%), skin catheter marks (54%), and symptomatic fat necrosis (15%). Breast asymmetry was reported in 73%. Rates of excellent-to-good cosmesis were similar between PROs (66%) and radiation oncologists (68%). The PROs of tx satisfaction at year-5 was 75%. RTOG 95-17 documents the year-5 skin toxicity and tx effects of mCathBrachy APBI, which are associated with PROs of good-to-excellent cosmesis and high tx satisfaction. This emphasizes the importance of PROs when assessing BrCa tx. National Surgical Adjuvant Breast and Bowel Project B39/RTOG 0413 will allow for definitive comparisons between APBI and whole breast radiation therapy. Copyright © 2014. Published by Elsevier Inc.

  10. Time-Driven Activity-Based Costing: A Comparative Cost Analysis of Whole-Breast Radiotherapy Versus Balloon-Based Brachytherapy in the Management of Early-Stage Breast Cancer.

    Science.gov (United States)

    Schutzer, Matthew E; Arthur, Douglas W; Anscher, Mitchell S

    2016-05-01

    Value in health care is defined as outcomes achieved per dollar spent, and understanding cost is critical to delivering high-value care. Traditional costing methods reflect charges rather than fundamental costs to provide a service. The more rigorous method of time-driven activity-based costing was used to compare cost between whole-breast radiotherapy (WBRT) and accelerated partial-breast irradiation (APBI) using balloon-based brachytherapy. For WBRT (25 fractions with five-fraction boost) and APBI (10 fractions twice daily), process maps were created outlining each activity from consultation to post-treatment follow up. Through staff interviews, time estimates were obtained for each activity. The capacity cost rates (CCR), defined as cost per minute, were calculated for personnel, equipment, and physical space. Total cost was calculated by multiplying the time required of each resource by its CCR. This was then summed and combined with cost of consumable materials. The total cost for WBRT was $5,333 and comprised 56% personnel costs and 44% space/equipment costs. For APBI, the total cost was $6,941 (30% higher than WBRT) and comprised 51% personnel costs, 6% space/equipment costs, and 43% consumable materials costs. The attending physician had the highest CCR of all personnel ($4.28/min), and APBI required 24% more attending time than WBRT. The most expensive activity for APBI was balloon placement and for WBRT was computed tomography simulation. APBI cost more than WBRT when using the dose/fractionation schemes analyzed. Future research should use time-driven activity-based costing to better understand cost with the aim of reducing expenditure and defining bundled payments. Copyright © 2016 by American Society of Clinical Oncology.

  11. 3D shape measurement system developed on mobile platform

    Science.gov (United States)

    Wu, Zhoujie; Chang, Meng; Shi, Bowen; Zhang, Qican

    2017-02-01

    Three-dimensional (3-D) shape measurement technology based on structured light has become one hot research field inspired by the increasing requirements. Many methods have been implemented and applied in the industry applications, but most of their equipments are large and complex, cannot be portable. Meanwhile, the popularity of the smart mobile terminals, such as smart phones, provides a platform for the miniaturization and portability of this technology. The measurement system based on phase-shift algorithm and Gray-code pattern under the Android platform on a mobile phone is mainly studied and developed, and it has been encapsulated into a mobile phone application in order to reconstruct 3-D shape data in the employed smart phone easily and quickly. The experimental results of two measured object are given in this paper and demonstrate the application we developed in the mobile platform is effective.

  12. Modeling and Correspondence of Topologically Complex 3D Shapes

    OpenAIRE

    Alhashim, Ibraheem

    2015-01-01

    3D shape creation and modeling remains a challenging task especially for novice users. Many methods in the field of computer graphics have been proposed to automate the often repetitive and precise operations needed during the modeling of detailed shapes. This report surveys different approaches of shape modeling and correspondence especially for shapes exhibiting topological complexity. We focus on methods designed to help generate or process shapes with large number of interconnected compon...

  13. An efficient memetic algorithm for 3D shape matching problems

    Science.gov (United States)

    Sharif Khan, Mohammad; Mohamad Ayob, Ahmad F.; Ray, Tapabrata

    2014-05-01

    Shape representation plays a vital role in any shape optimization exercise. The ability to identify a shape with good functional properties is dependent on the underlying shape representation scheme, the morphing mechanism and the efficiency of the optimization algorithm. This article presents a novel and efficient methodology for morphing 3D shapes via smart repair of control points. The repaired sequence of control points are subsequently used to define the 3D object using a B-spline surface representation. The control points are evolved within the framework of a memetic algorithm for greater efficiency. While the authors have already proposed an approach for 2D shape matching, this article extends it further to deal with 3D shape matching problems. Three 3D examples and a real customized 3D earplug design have been used as examples to illustrate the performance of the proposed approach and the effectiveness of the repair scheme. Complete details of the problems are presented for future work in this direction.

  14. TU-AB-201-11: A Novel Theoretical Framework for MRI-Only Image Guided LDR Prostate and Breast Brachytherapy Implant Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Soliman, A; Elzibak, A; Fatemi, A; Safigholi, H; Ravi, A; Morton, G; Song, W [Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada); Han, D [Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, Ontario (Canada); University of California, San Diego, La Jolla, CA (United States)

    2015-06-15

    Purpose: To propose a novel framework for accurate model-based dose calculations using only MR images for LDR prostate and breast seed implant brachytherapy. Methods: Model-based dose calculation methodologies recommended by TG-186 require further knowledge about specific tissue composition, which is challenging with MRI. However, relying on MRI-only for implant dosimetry would reduce the soft tissue delineation uncertainty, costs, and uncertainties associated with multi-modality registration and fusion processes. We propose a novel framework to address this problem using quantitative MRI acquisitions and reconstruction techniques. The framework includes three steps: (1) Identify the locations of seeds(2) Identify the presence (or absence) of calcification(s)(3) Quantify the water and fat content in the underlying tissueSteps (1) and (2) consider the sources that limit patient dosimetry, particularly the inter-seed attenuation and the calcified regions; while step (3) targets the quantification of the tissue composition to consider the heterogeneities in the medium. Our preliminary work has shown that the seeds and the calcifications can be identified with MRI using both the magnitude and the phase images. By employing susceptibility-weighted imaging with specific post-processing techniques, the phase images can be further explored to distinguish the seeds from the calcifications. Absolute quantification of tissue, water, and fat content is feasible and was previously demonstrated in phantoms and in-vivo applications, particularly for brain diseases. The approach relies on the proportionality of the MR signal to the number of protons in an image volume. By employing appropriate correction algorithms for T1 - and T2*-related biases, B1 transmit and receive field inhomogeneities, absolute water/fat content can be determined. Results: By considering calcification and interseed attenuation, and through the knowledge of water and fat mass density, accurate patient

  15. Objective method to report planner-independent skin/rib maximal dose in balloon-based high dose rate (HDR) brachytherapy for breast cancer.

    Science.gov (United States)

    Kim, Yongbok; Trombetta, Mark G

    2011-04-01

    An objective method was proposed and compared with a manual selection method to determine planner-independent skin and rib maximal dose in balloon-based high dose rate (HDR) brachytherapy planning. The maximal dose to skin and rib was objectively extracted from a dose volume histogram (DVH) of skin and rib volumes. A virtual skin volume was produced by expanding the skin surface in three dimensions (3D) external to the breast with a certain thickness in the planning computed tomography (CT) images. Therefore, the maximal dose to this volume occurs on the skin surface the same with a conventional manual selection method. The rib was also delineated in the planning CT images and its maximal dose was extracted from its DVH. The absolute (Abdiff = [D(max) Man - D (max)DVH]) and relative (Rediff[%] = 100 x ([D(max)Man-D(max)DVH])/D(max)DVH) maximal skin and rib dose differences between the manual selection method (D(max)Man) and the objective method (D(max)DVH) were measured for 50 balloon-based HDR (25 MammoSite and 25 Contura) patients. The average +/- standard deviation of maximal dose difference was 1.67% +/- 1.69% of the prescribed dose (PD). No statistical difference was observed between MammoSite and Contura patients for both Abdiff and Rediff[%] values. However, a statistically significant difference (p value skin dose difference for both Abdiff (2.30% +/- 1.71% vs 1.05% +/- 1.43%) and Rediff[%] (2.32% +/- 1.79% vs 1.21% +/- 1.41%). In general, rib has a more irregular contour and it is more proximally located to the balloon for 50 HDR patients. Due to the inverse square law factor, more dose difference was observed in higher dose range (D(max) > 90%) compared with lower dose range (D(max) skin and rib can determine the planner-independent maximal dose compared with the manual selection method. However, the difference was < 2% of PD, on average, if appropriate attention is paid to selecting a manual dose point in 3D planning CT images.

  16. Objective method to report planner-independent skin/rib maximal dose in balloon-based high dose rate (HDR) brachytherapy for breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yongbok; Trombetta, Mark G. [Department of Radiation Oncology, Allegheny General Hospital, Pittsburgh, Pennsylvania 15212 (United States) and Drexel University College of Medicine, Allegheny Campus, Pittsburgh, Pennsylvania 15212 (United States)

    2011-04-15

    Purpose: An objective method was proposed and compared with a manual selection method to determine planner-independent skin and rib maximal dose in balloon-based high dose rate (HDR) brachytherapy planning. Methods: The maximal dose to skin and rib was objectively extracted from a dose volume histogram (DVH) of skin and rib volumes. A virtual skin volume was produced by expanding the skin surface in three dimensions (3D) external to the breast with a certain thickness in the planning computed tomography (CT) images. Therefore, the maximal dose to this volume occurs on the skin surface the same with a conventional manual selection method. The rib was also delineated in the planning CT images and its maximal dose was extracted from its DVH. The absolute (Abdiff=|D{sub max}{sup Man}-D{sub max}{sup DVH}|) and relative (Rediff[%]=100x(|D{sub max}{sup Man}-D{sub max}{sup DVH}|)/D{sub max}{sup DVH}) maximal skin and rib dose differences between the manual selection method (D{sub max}{sup Man}) and the objective method (D{sub max}{sup DVH}) were measured for 50 balloon-based HDR (25 MammoSite and 25 Contura) patients. Results: The average{+-}standard deviation of maximal dose difference was 1.67%{+-}1.69% of the prescribed dose (PD). No statistical difference was observed between MammoSite and Contura patients for both Abdiff and Rediff[%] values. However, a statistically significant difference (p value <0.0001) was observed in maximal rib dose difference compared with maximal skin dose difference for both Abdiff (2.30%{+-}1.71% vs 1.05%{+-}1.43%) and Rediff[%] (2.32%{+-}1.79% vs 1.21%{+-}1.41%). In general, rib has a more irregular contour and it is more proximally located to the balloon for 50 HDR patients. Due to the inverse square law factor, more dose difference was observed in higher dose range (D{sub max}>90%) compared with lower dose range (D{sub max}<90%): 2.16%{+-}1.93% vs 1.19%{+-}1.25% with p value of 0.0049. However, the Rediff[%] analysis eliminated the

  17. Advancements in brachytherapy

    DEFF Research Database (Denmark)

    Tanderup, Kari; Ménard, Cynthia; Polgar, Csaba

    2017-01-01

    Brachytherapy is a radiotherapy modality associated with a highly focal dose distribution. Brachytherapy treats the cancer tissue from the inside, and the radiation does not travel through healthy tissue to reach the target as with external beam radiotherapy techniques. The nature of brachytherap...... in terms of controlling dose and demonstrating excellent clinical outcome. Interests in focal, hypofractionated and adaptive treatments are increasing, and brachytherapy has significant potential to develop further in these directions with current and new treatment indications....

  18. Prostate brachytherapy - discharge

    Science.gov (United States)

    Implant therapy - prostate cancer - discharge; Radioactive seed placement - discharge ... You had a procedure called brachytherapy to treat prostate cancer. Your treatment lasted 30 minutes or more, ...

  19. Skin and chest wall dose with multi-catheter and MammoSite breast brachytherapy: Implications for late toxicity.

    Science.gov (United States)

    Cuttino, Laurie W; Todor, Dorin; Rosu, Miheala; Arthur, Douglas W

    2009-01-01

    Accelerated partial breast irradiation (APBI) continues to increase in popularity. Up to 14% of patients treated with the MammoSite (MS) report some degree of chronic pain, which may be related to chest wall toxicity. Reports from several institutions using the multicatheter (MC) technique have not shown associated elevated chest wall toxicity. Additionally, a recent investigation has suggested that increased toxicity may occur with the MS when the dose to the chest wall exceeds 125% of the prescribed dose. This investigation compares the skin and chest wall doses of a cohort of patients treated with the MC technique to a group treated with the MS. The dosimetric data for 43 patients treated with the MC technique and 83 patients treated with the MS at Virginia Commonwealth University were reviewed. This cohort represents consecutively treated patients from our most recent experience to minimize any learning curve effect on dosimetry. Plans were generated using 3D software (Brachyvision, Varian Medical Systems, Inc., Palo Alto, CA). Multiple dwell positions were used for all MS patients to optimize dose delivery. The minimum distances from the planning target volume to the skin and chest wall were calculated, as well as the maximum doses delivered to the skin and chest wall. The mean skin distances for patients treated with the MC technique and the MS were 0.5 and 0.9cm, respectively (pskin distance, the mean skin dose for the MC technique was only 2.3Gy per fraction (67% of prescription dose). The mean skin dose for the MS was 3.2Gy per fraction (94% of prescription dose, pskin dose for the MS was 3.6Gy per fraction (105% of prescription dose, pskin doses in excess of 125% for the MC and MS were 0% and 9.6%, respectively. The percentage of patients receiving chest wall doses in excess of 125% for the MC and MS were 0% and 38.6%, respectively. The MC technique results in more conformal dose delivery, with significantly lower mean skin and chest wall doses. Treatment

  20. Aesthetic preference recognition of 3D shapes using EEG.

    Science.gov (United States)

    Chew, Lin Hou; Teo, Jason; Mountstephens, James

    2016-04-01

    Recognition and identification of aesthetic preference is indispensable in industrial design. Humans tend to pursue products with aesthetic values and make buying decisions based on their aesthetic preferences. The existence of neuromarketing is to understand consumer responses toward marketing stimuli by using imaging techniques and recognition of physiological parameters. Numerous studies have been done to understand the relationship between human, art and aesthetics. In this paper, we present a novel preference-based measurement of user aesthetics using electroencephalogram (EEG) signals for virtual 3D shapes with motion. The 3D shapes are designed to appear like bracelets, which is generated by using the Gielis superformula. EEG signals were collected by using a medical grade device, the B-Alert X10 from advance brain monitoring, with a sampling frequency of 256 Hz and resolution of 16 bits. The signals obtained when viewing 3D bracelet shapes were decomposed into alpha, beta, theta, gamma and delta rhythm by using time-frequency analysis, then classified into two classes, namely like and dislike by using support vector machines and K-nearest neighbors (KNN) classifiers respectively. Classification accuracy of up to 80 % was obtained by using KNN with the alpha, theta and delta rhythms as the features extracted from frontal channels, Fz, F3 and F4 to classify two classes, like and dislike.

  1. Exploration of continuous variability in collections of 3D shapes

    KAUST Repository

    Ovsjanikov, Maks

    2011-07-01

    As large public repositories of 3D shapes continue to grow, the amount of shape variability in such collections also increases, both in terms of the number of different classes of shapes, as well as the geometric variability of shapes within each class. While this gives users more choice for shape selection, it can be difficult to explore large collections and understand the range of variations amongst the shapes. Exploration is particularly challenging for public shape repositories, which are often only loosely tagged and contain neither point-based nor part-based correspondences. In this paper, we present a method for discovering and exploring continuous variability in a collection of 3D shapes without correspondences. Our method is based on a novel navigation interface that allows users to explore a collection of related shapes by deforming a base template shape through a set of intuitive deformation controls. We also help the user to select the most meaningful deformations using a novel technique for learning shape variability in terms of deformations of the template. Our technique assumes that the set of shapes lies near a low-dimensional manifold in a certain descriptor space, which allows us to avoid establishing correspondences between shapes, while being rotation and scaling invariant. We present results on several shape collections taken directly from public repositories. © 2011 ACM.

  2. Automatic Reconstruction of Spacecraft 3D Shape from Imagery

    Science.gov (United States)

    Poelman, C.; Radtke, R.; Voorhees, H.

    We describe a system that computes the three-dimensional (3D) shape of a spacecraft from a sequence of uncalibrated, two-dimensional images. While the mathematics of multi-view geometry is well understood, building a system that accurately recovers 3D shape from real imagery remains an art. A novel aspect of our approach is the combination of algorithms from computer vision, photogrammetry, and computer graphics. We demonstrate our system by computing spacecraft models from imagery taken by the Air Force Research Laboratory's XSS-10 satellite and DARPA's Orbital Express satellite. Using feature tie points (each identified in two or more images), we compute the relative motion of each frame and the 3D location of each feature using iterative linear factorization followed by non-linear bundle adjustment. The "point cloud" that results from this traditional shape-from-motion approach is typically too sparse to generate a detailed 3D model. Therefore, we use the computed motion solution as input to a volumetric silhouette-carving algorithm, which constructs a solid 3D model based on viewpoint consistency with the image frames. The resulting voxel model is then converted to a facet-based surface representation and is texture-mapped, yielding realistic images from arbitrary viewpoints. We also illustrate other applications of the algorithm, including 3D mensuration and stereoscopic 3D movie generation.

  3. Radiation dose to the left anterior descending coronary artery during interstitial pulsed-dose-rate brachytherapy used as a boost in breast cancer patients undergoing organ-sparing treatment

    Directory of Open Access Journals (Sweden)

    Marcin Sinacki

    2017-02-01

    Full Text Available Purpose: To assess dose received by the left anterior descending (LAD coronary artery during interstitial pulsed-dose-rate brachytherapy (PDR-BT boost for left-sided breast cancer patients undergoing organ-sparing treatment. Material and methods : Thirty consecutive pT1-3N0-1M0 breast cancer patients boosted between 2014 and 2015 with 10 Gy/10 pulses/hour PDR-BT following a computed tomography (CT simulation with the multi-catheter implant were included. The most common localization of primary tumor were upper quadrants. Patients were implanted with rigid tubes following breast conserving surgery and whole breast external beam irradiation (40 Gy/15 or 50 Gy/25 fractions. Computed tomography scans were retrospectively reviewed and LADs were contoured without and with margin of 5 mm (LAD 5mm . Standard treatment plan encompassed tumor bed determined by the surgical clips with margin of 2 cm. Dosimetric parameters were extracted from the dose-volume histograms. Results : The mean D 90 and V 100 were 10.3 Gy (range: 6.6-13.3, and 42.0 cc (range: 15.3-109.3, respectively. The median dose non-uniformity ratio (DNR was 0.50 (range: 0.27-0.82. The mean doses to LAD and LAD 5mm were 1.0 Gy and 0.96 Gy, and maximal doses were 1.57 Gy and 1.99 Gy, respectively. Dose to the 0.1 cc of the LAD and LAD 5mm were 1.42 Gy and 1.85 Gy (range: 0.01-4.98 Gy and 0.1-6.89 Gy, respectively. Conclusions : Interstitial multi-catheter PDR-BT used as a boost for left-sided breast cancer is generally associated with low dose to the LAD. However, higher dose in individual cases may require alternative approaches.

  4. Image guided, adaptive, accelerated, high dose brachytherapy as model for advanced small volume radiotherapy.

    Science.gov (United States)

    Haie-Meder, Christine; Siebert, Frank-André; Pötter, Richard

    2011-09-01

    Brachytherapy has consistently provided a very conformal radiation therapy modality. Over the last two decades this has been associated with significant improvements in imaging for brachytherapy applications (prostate, gynecology), resulting in many positive advances in treatment planning, application techniques and clinical outcome. This is emphasized by the increased use of brachytherapy in Europe with gynecology as continuous basis and prostate and breast as more recently growing fields. Image guidance enables exact knowledge of the applicator together with improved visualization of tumor and target volumes as well as of organs at risk providing the basis for very individualized 3D and 4D treatment planning. In this commentary the most important recent developments in prostate, gynecological and breast brachytherapy are reviewed, with a focus on European recent and current research aiming at the definition of areas for important future research. Moreover the positive impact of GEC-ESTRO recommendations and the highlights of brachytherapy physics are discussed what altogether presents a full overview of modern image guided brachytherapy. An overview is finally provided on past and current international brachytherapy publications focusing on "Radiotherapy and Oncology". These data show tremendous increase in almost all research areas over the last three decades strongly influenced recently by translational research in regard to imaging and technology. In order to provide high level clinical evidence for future brachytherapy practice the strong need for comprehensive prospective clinical research addressing brachytherapy issues is high-lighted. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. Use of ultrasound in image-guided high-dose-rate brachytherapy: enumerations and arguments

    Science.gov (United States)

    Kataria, Tejinder; Gupta, Deepak; Goyal, Shikha; Bisht, Shyam Singh; Basu, Trinanjan; Abhishek, Ashu

    2017-01-01

    Inherently, brachytherapy is the most conformal radiotherapeutic technique. As an aid to brachytherapy, ultrasonography (USG) serves as a portable, inexpensive, and simple to use method allowing for accurate, reproducible, and adaptive treatments. Some newer brachytherapy planning systems have incorporated USG as the sole imaging modality. Ultrasonography has been successfully used to place applicator and dose planning for prostate, cervix, and anal canal cancers. It can guide placement of brachytherapy catheters for all other sites like breast, skin, and head and neck cancers. Traditional USG has a few limitations, but recent advances such as 3-dimensional (3D) USG and contrast USG have enhanced its potential as a dependable guide in high-dose-rate image-guided brachytherapy (HDR-IGBT). The authors in this review have attempted to enumerate various aspects of USG in brachytherapy, highlighting its use across various sites. PMID:28533803

  6. Use of ultrasound in image-guided high-dose-rate brachytherapy: enumerations and arguments

    Directory of Open Access Journals (Sweden)

    Susovan Banerjee

    2017-04-01

    Full Text Available Inherently, brachytherapy is the most conformal radiotherapeutic technique. As an aid to brachytherapy, ultrasonography (USG serves as a portable, inexpensive, and simple to use method allowing for accurate, reproducible, and adaptive treatments. Some newer brachytherapy planning systems have incorporated USG as the sole imaging modality. Ultrasonography has been successfully used to place applicator and dose planning for prostate, cervix, and anal canal cancers. It can guide placement of brachytherapy catheters for all other sites like breast, skin, and head and neck cancers. Traditional USG has a few limitations, but recent advances such as 3-dimensional (3D USG and contrast USG have enhanced its potential as a dependable guide in high-dose-rate image-guided brachytherapy (HDR-IGBT. The authors in this review have attempted to enumerate various aspects of USG in brachytherapy, highlighting its use across various sites.

  7. 3D shaping of electron beams using amplitude masks

    Energy Technology Data Exchange (ETDEWEB)

    Shiloh, Roy, E-mail: royshilo@post.tau.ac.il; Arie, Ady

    2017-06-15

    Highlights: • Electron beams are shaped in 3D with examples of curves and lattices. • Computer generated holograms are manifested as binary amplitude masks. • Applications in electron-optical particle trapping, manipulation, and synthesis. • Electron beam lithography fabrication scheme explained in detail. • Measurement paradigms of 3D shaped beams are discussed. - Abstract: Shaping the electron wavefunction in three dimensions may prove to be an indispensable tool for research involving atomic-sized particle trapping, manipulation, and synthesis. We utilize computer-generated holograms to sculpt electron wavefunctions in a standard transmission electron microscope in 3D, and demonstrate the formation of electron beams exhibiting high intensity along specific trajectories as well as shaping the beam into a 3D lattice of hot-spots. The concepts presented here are similar to those used in light optics for trapping and tweezing of particles, but at atomic scale resolutions.

  8. Reconstruction of hidden 3D shapes using diffuse reflections

    CERN Document Server

    Gupta, Otkrist; Willwacher, Thomas; Veeraraghavan, Ashok; Raskar, Ramesh

    2012-01-01

    We analyze multi-bounce propagation of light in an unknown hidden volume and demonstrate that the reflected light contains sufficient information to recover the 3D structure of the hidden scene. We formulate the forward and inverse theory of secondary and tertiary scattering reflection using ideas from energy front propagation and tomography. We show that using careful choice of approximations, such as Fresnel approximation, greatly simplifies this problem and the inversion can be achieved via a backpropagation process. We provide a theoretical analysis of the invertibility, uniqueness and choices of space-time-angle dimensions using synthetic examples. We show that a 2D streak camera can be used to discover and reconstruct hidden geometry. Using a 1D high speed time of flight camera, we show that our method can be used recover 3D shapes of objects "around the corner".

  9. Parameterization adaption for 3D shape optimization in aerodynamics

    Directory of Open Access Journals (Sweden)

    Badr Abou El Majd

    2013-10-01

    Full Text Available When solving a PDE problem numerically, a certain mesh-refinement process is always implicit, and very classically, mesh adaptivity is a very effective means to accelerate grid convergence. Similarly, when optimizing a shape by means of an explicit geometrical representation, it is natural to seek for an analogous concept of parameterization adaptivity. We propose here an adaptive parameterization for three-dimensional optimum design in aerodynamics by using the so-called “Free-Form Deformation” approach based on 3D tensorial Bézier parameterization. The proposed procedure leads to efficient numerical simulations with highly reduced computational costs.[How to cite this article:  Majd, B.A.. 2014. Parameterization adaption for 3D shape optimization in aerodynamics. International Journal of Science and Engineering, 6(1:61-69. Doi: 10.12777/ijse.6.1.61-69

  10. Advancements in brachytherapy.

    Science.gov (United States)

    Tanderup, Kari; Ménard, Cynthia; Polgar, Csaba; Lindegaard, Jacob Christian; Kirisits, Christian; Pötter, Richard

    2017-01-15

    Brachytherapy is a radiotherapy modality associated with a highly focal dose distribution. Brachytherapy treats the cancer tissue from the inside, and the radiation does not travel through healthy tissue to reach the target as with external beam radiotherapy techniques. The nature of brachytherapy makes it attractive for boosting limited size target volumes to very high doses while sparing normal tissues. Significant developments over the last decades have increased the use of 3D image guided procedures with the utilization of CT, MRI, US and PET. This has taken brachytherapy to a new level in terms of controlling dose and demonstrating excellent clinical outcome. Interests in focal, hypofractionated and adaptive treatments are increasing, and brachytherapy has significant potential to develop further in these directions with current and new treatment indications. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. SU-F-T-60: A Quick Dose Calculation Check for Accuboost Breast Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Sen, A [Cancer Treatment Center of America, Tulsa, OK (United States)

    2016-06-15

    Purpose: Accuboost treatment planning uses dwell times from a nomogram designed with Monte Carlo calculations for round and D-shaped applicators. A quick dose calculation method has been developed for verification of the HDR Brachytherapy dose as a second check. Methods: Accuboost breast treatment uses several round and D-shaped applicators to be used non-invasively with an Ir-192 source from a HDR Brachytherapy afterloader after the breast is compressed in a mammographic unit for localization. The breast thickness, source activity, the prescription dose and the applicator size are entered into a nomogram spreadsheet which gives the dwell times to be manually entered into the delivery computer. Approximating the HDR Ir-192 as a point source, and knowing the geometry of the round and D-applicators, the distances from the source positions to the midpoint of the central plane are calculated. Using the exposure constant of Ir-192 and medium as human tissue, the dose at a point is calculated as: D(cGy) = 1.254 × A × t/R2, where A is the activity in Ci, t is the dwell time in sec and R is the distance in cm. The dose from each dwell position is added to get the total dose. Results: Each fraction is delivered in two compressions: cranio-caudally and medial-laterally. A typical APBI treatment in 10 fractions requires 20 compressions. For a patient treated with D45 applicators and an average of 5.22 cm thickness, this calculation was 1.63 % higher than the prescription. For another patient using D53 applicators in the CC direction and 7 cm SDO applicators in the ML direction, this calculation was 1.31 % lower than the prescription. Conclusion: This is a simple and quick method to double check the dose on the central plane for Accuboost treatment.

  12. Brachytherapy in lip cancer.

    Science.gov (United States)

    Rovirosa-Casino, Angeles; Planas-Toledano, Isabel; Ferre-Jorge, Jorge; Oliva-Díez, José María; Conill-Llobet, Carlos; Arenas-Prat, Meritxell

    2006-05-01

    Lip cancer is one of the most prevalent skin tumours of the head and neck. The characteristics of the tumour relate to their exophyitic growth in an area of easy visual acces which allows their diagnosis in early stages. As a result, there is a better prognosis with the present treatments. In early stages the treatment can be performed by surgery or by brachytherapy, and the results are similar on local control; nevertheless brachytherapy offers the best functional and esthetic results. We are reporting on a review of the literature in relation to indications, techniques and results of brachytherapy for lip cancer.

  13. Progressive 3D shape abstraction via hierarchical CSG tree

    Science.gov (United States)

    Chen, Xingyou; Tang, Jin; Li, Chenglong

    2017-06-01

    A constructive solid geometry(CSG) tree model is proposed to progressively abstract 3D geometric shape of general object from 2D image. Unlike conventional ones, our method applies to general object without the need for massive CAD models, and represents the object shapes in a coarse-to-fine manner that allows users to view temporal shape representations at any time. It stands in a transitional position between 2D image feature and CAD model, benefits from state-of-the-art object detection approaches and better initializes CAD model for finer fitting, estimates 3D shape and pose parameters of object at different levels according to visual perception objective, in a coarse-to-fine manner. Two main contributions are the application of CSG building up procedure into visual perception, and the ability of extending object estimation result into a more flexible and expressive model than 2D/3D primitive shapes. Experimental results demonstrate the feasibility and effectiveness of the proposed approach.

  14. The American College of Radiology and the American Brachytherapy Society practice parameter for the performance of low-dose-rate brachytherapy.

    Science.gov (United States)

    Viswanathan, Akila N; Erickson, Beth A; Ibbott, Geoffrey S; Small, William; Eifel, Patricia J

    Brachytherapy is the use of radionuclides to treat malignancies or benign conditions by means of a radiation source placed close to or into the tumor or treatment site. This practice parameter refers only to the use of radionuclide brachytherapy. Brachytherapy alone or combined with external beam therapy plays an important role in the management and treatment of patients with cancer. Low-dose-rate (LDR) brachytherapy has traditionally been used for treating prostate, head and neck, breast, cervical, and endometrial cancers as well as obstructive bile duct, esophageal, or bronchial lesions. It has been practiced for over a century with a variety of sources including radium-226, cesium-137, and, more recently, iridium- 192, iodine-125, and palladium-103. Low-dose-rate (LDR) brachytherapy can be given as interstitial, intracavitary, intraluminal, and/or plesiotherapy to a wide variety of treatment sites. This practice parameter addresses sealed sources as they are used for LDR brachytherapy. It is recognized that unsealed sources (e.g., yttrium-90) are also a form of LDR brachytherapy. Copyright © 2016 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.

  15. Recommendations from GEC ESTRO Breast Cancer Working Group (I): Target definition and target delineation for accelerated or boost Partial Breast Irradiation using multicatheter interstitial brachytherapy after breast conserving closed cavity surgery.

    Science.gov (United States)

    Strnad, Vratislav; Hannoun-Levi, Jean-Michel; Guinot, Jose-Luis; Lössl, Kristina; Kauer-Dorner, Daniela; Resch, Alexandra; Kovács, György; Major, Tibor; Van Limbergen, Erik

    2015-06-01

    The aim was to develop a delineation guideline for target definition for APBI or boost by consensus of the Breast Working Group of GEC-ESTRO. Appropriate delineation of CTV (PTV) with low inter- and intra-observer variability in clinical practice is complex and needs various steps as: (1) Detailed knowledge of primary surgical procedure, of all details of pathology, as well as of preoperative imaging. (2) Definition of tumour localization before breast conserving surgery inside the breast and translation of this information in the postoperative CT imaging data set. (3) Calculation of the size of total safety margins. The size should be at least 2 cm. (4) Definition of the target. (5) Delineation of the target according to defined rules. Providing guidelines based on the consensus of a group of experts should make it possible to achieve a reproducible and consistent definition of CTV (PTV) for Accelerated Partial Breast Irradiation (APBI) or boost irradiation after breast conserving closed cavity surgery, and helps to define it after selected cases of oncoplastic surgery. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2012-06-07

    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.

  17. MRI-guided brachytherapy

    Science.gov (United States)

    Tanderup, Kari; Viswanathan, Akila; Kirisits, Christian; Frank, Steven J.

    2014-01-01

    The application of MRI-guided brachytherapy has demonstrated significant growth during the last two decades. Clinical improvements in cervix cancer outcomes have been linked to the application of repeated MRI for identification of residual tumor volumes during radiotherapy. This has changed clinical practice in the direction of individualized dose administration, and mounting evidence of improved clinical outcome with regard to local control, overall survival as well as morbidity. MRI-guided prostate HDR and LDR brachytherapy has improved the accuracy of target and organs-at-risk (OAR) delineation, and the potential exists for improved dose prescription and reporting for the prostate gland and organs at risk. Furthermore, MRI-guided prostate brachytherapy has significant potential to identify prostate subvolumes and dominant lesions to allow for dose administration reflecting the differential risk of recurrence. MRI-guided brachytherapy involves advanced imaging, target concepts, and dose planning. The key issue for safe dissemination and implementation of high quality MRI-guided brachytherapy is establishment of qualified multidisciplinary teams and strategies for training and education. PMID:24931089

  18. Dosimetric audit in brachytherapy

    Science.gov (United States)

    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

  19. Canadian prostate brachytherapy in 2012

    Science.gov (United States)

    Keyes, Mira; Crook, Juanita; Morris, W. James; Morton, Gerard; Pickles, Tom; Usmani, Nawaid; Vigneault, Eric

    2013-01-01

    Prostate brachytherapy can be used as a monotherapy for low- and intermediate-risk patients or in combination with external beam radiation therapy (EBRT) as a form of dose escalation for selected intermediate- and high-risk patients. Prostate brachytherapy with either permanent implants (low dose rate [LDR]) or temporary implants (high dose rate [HDR]) is emerging as the most effective radiation treatment for prostate cancer. Several large Canadian brachytherapy programs were established in the mid- to late-1990s. Prostate brachytherapy is offered in British Columbia, Alberta, Manitoba, Ontario, Quebec and New Brunswick. We anticipate the need for brachytherapy services in Canada will significantly increase in the near future. In this review, we summarize brachytherapy programs across Canada, contemporary eligibility criteria for the procedure, toxicity and prostate-specific antigen recurrence free survival (PRFS), as published from Canadian institutions for both LDR and HDR brachytherapy. PMID:23671495

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

    Science.gov (United States)

    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. Copyright © 2014 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  1. Initial clinical experience with the Strut-Adjusted Volume Implant (SAVI) breast brachytherapy device for accelerated partial-breast irradiation (APBI): first 100 patients with more than 1 year of follow-up.

    Science.gov (United States)

    Yashar, Catheryn M; Scanderbeg, Daniel; Kuske, Robert; Wallace, Anne; Zannis, Victor; Blair, Sarah; Grade, Emily; Swenson, Virginia H; Quiet, Coral

    2011-07-01

    The Strut-Adjusted Volume Implant (SAVI; Cianna Medical, Aliso Viejo, CA) is a multichannel single-entry brachytherapy device designed to allow dose modulation to minimize normal tissue dose while simultaneously maximizing target coverage. This is the first report on the initial 102 patients with nearly 2 years of median follow-up. One hundred two patients were treated at two institutions. Data were collected on eligibility and dosimetry and followed for toxicity and recurrence. The median follow-up is 21 months. Overall dosimetry is outstanding (median percent of target volume receiving 90% of the prescription dose was 95.9%, volume of target receiving 150% of the prescription dose was 27.8 mL, and volume of target receiving 200% of the prescription dose was 14.0 cm(3)). No devices were pulled prior to treatment completion. For patients with a skin bridge of less than 7 mm, the maximum median skin dose was 280 cGy (median percent of target volume receiving 90% of the prescription dose was 95.2%, volume of target receiving 150% of the prescription dose was 25.8 cm(3) and volume of target receiving 200% of the prescription dose was 12.7 mL). For patients with both chest wall and skin of less than 7 mm, the maximum median lung dose was 205 cGy with simultaneous skin dose of 272 cGy. The rate of telangiectasia was 1.9%. Grade 1 hyperpigmentation developed in 10 patients (9.8%) and Grade 2 fibrosis in 2 patients (1.9%). There were 2 symptomatic seromas and 2 cases of asymptomatic fat necrosis (1.9%). Of the patients, 27% were not eligible for MammoSite balloon brachytherapy (Hologic, Inc., Marlborough, MA) and 5% were not eligible for any balloon brachytherapy. The recurrence rate was 1%. The SAVI appears to safely allow an increase in eligibility for APBI over balloon brachytherapy or three-dimensional conformal radiation, highlighting the outstanding device flexibility to maximize the target dose and minimize the normal tissue dose. The device was well tolerated by

  2. Development of the 3D Shape Shearography Technique for Strain Inspection of Curved Objects

    OpenAIRE

    Anisimov, A.; Serikova, M.G.; Groves, R.M.

    2016-01-01

    Practical development questions of 3D shape shearography technique for surface strain inspection of curved objects are discussed. Results of a global cameras-projector system calibration and different methods of shear distance estimation in 3D are presented

  3. Changes in brachytherapy-based APBI patient selection immediately before and after publication of the ASTRO consensus statement.

    Science.gov (United States)

    Husain, Zain A; Lloyd, Shane; Shah, Chirag; Wilson, Lynn D; Koshy, Matthew; Mahmood, Usama

    2015-01-01

    In July 2009, American Society of Radiation Oncology (ASTRO) released a consensus statement (CS) to guide patient selection for accelerated partial breast irradiation (APBI). The goal of this study was to examine how practice patterns changed following the guideline's release. The Surveillance, Epidemiology, and End Results database was queried from 2008 to 2010 for females aged ≥20 years receiving breast conservation via brachytherapy. Among the APBI cohort, characteristics and CS grouping ("suitable," "cautionary," or "unsuitable") of patients receiving APBI in the 18 months before (January 2008 to June 2009) and after (July 2009 to December 2010) guideline publication were analyzed. A total of 87,528 patients undergoing breast conservation therapy were identified. Of this, 4,253 patients (4.9%) received brachytherapy-based APBI. Limiting the analysis to patients not missing data that would affect their CS classification rendered 3,828 patients. The proportion of breast conservation patients receiving brachytherapy-based APBI before and after CS release remained the same (4.9% vs. 4.8%, p = 0.36). Among patients receiving brachytherapy-based APBI, the unsuitable category decreased (15.8 vs. 11.1%, p ASTRO CS was associated with a decrease in "unsuitable" patients and an increase in "suitable" patients being treated with brachytherapy-based APBI. This trend began before guideline release and thus cannot be definitively attributed to the ASTRO CS. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  4. Genetic Fuzzy Prediction of Mass Perception in Non-Functional 3D Shapes

    DEFF Research Database (Denmark)

    Achiche, Sofiane

    2010-01-01

    and their perception by observers. The link between geometry and human perception is created using a genetic learning algorithm combined with a fuzzy logic decision support system. Human evaluations of the non-functional 3D shapes against two contrary perception adjectives (massive versus lightweight) are used...... as the learning data set. The non-functional 3D shapes were designed by engineering design students from the Technical University of Denmark who were asked to design non-functional 3D shapes evoking either the adjective massive or light. Eight fuzzy models were developed: three (3) models constructed manually...... by the author and five (5) genetically generated. The fuzzy models were constructed using different sets of inputs of quantitative geometric properties. Combination of the different inputs resulted in different sets of fuzzy rules that can eventually be used as design guidelines for designers. The results...

  5. Modulation measuring profilometry with cross grating projection and single shot for dynamic 3D shape measurement

    Science.gov (United States)

    Lu, Mingteng; Su, Xianyu; Cao, Yiping; You, Zhisheng; Zhong, Min

    2016-12-01

    In order to determine Dynamic 3-D shape with vertical measurement mode, a fast modulation measuring profilometry (MMP) with a cross grating projection and single shot is proposed. Unlike the previous methods, in our current projection system, one cross grating is projected by a special projection lens consisting of a common projection lens and a cylindrical lens. Due to the characteristics of cylindrical lens, the image of the vertical component and the horizontal component of the cross grating is separated in the image space, and the measuring range is just the space between the two image planes. Through a beam splitter, the CCD camera can coaxially capture the fringe pattern of the cross grating modulated by the testing object's shape. In one fringe pattern, by applying Fourier transform, filtering and inverse Fourier transform, the modulation corresponding to the vertical and horizontal components of the cross grating can be obtained respectively. Then the 3-D shape of the object can be reconstructed according to the mapping relationship between modulation and height, which was established by calibration process in advance. So the 3-D shape information can be recorded at the same speed of the frame rate of the CCD camera. This paper gives the principle of the proposed method and the set-up for measuring experiment and system calibration. The 3-D shape of a still object and a dynamic process of liquid vortex were measured and reconstructed in the experiments, and the results proved the method's feasibility. The advantage of the proposed method is that only one fringe pattern is needed to extract the modulation distribution and to reconstruct the 3-D shape of the object. Therefore, the proposed method can achieve high speed measurement and vertical measurement without shadow and occlusion. It can be used in the dynamic 3-D shape measurement and vibration analysis.

  6. Performance analysis of 3-D shape measurement algorithm with a short baseline projector-camera system

    OpenAIRE

    Liu, Jianyang; Li, Youfu

    2014-01-01

    A number of works for 3-D shape measurement based on structured light have been well-studied in the last decades. A common way to model the system is to use the binocular stereovision-like model. In this model, the projector is treated as a camera, thus making a projector-camera-based system unified with a well-established traditional binocular stereovision system. After calibrating the projector and camera, a 3-D shape information is obtained by conventional triangulation. However, in such a...

  7. An approach to using conventional brachytherapy software for clinical treatment planning of complex, Monte Carlo-based brachytherapy dose distributions

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, Mark J.; Melhus, Christopher S.; Granero, Domingo; Perez-Calatayud, Jose; Ballester, Facundo [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States); Radiation Oncology Department, Physics Section, ' ' La Fe' ' University Hospital, Avenida Campanar 21, E-46009 Valencia (Spain); Department of Atomic, Molecular, and Nuclear Physics, University of Valencia, C/Dr. Moliner 50, E-46100 Burjassot, Spain and IFIC (University of Valencia-CSIC), C/Dr. Moliner 50, E-46100 Burjassot (Spain)

    2009-06-15

    Certain brachytherapy dose distributions, such as those for LDR prostate implants, are readily modeled by treatment planning systems (TPS) that use the superposition principle of individual seed dose distributions to calculate the total dose distribution. However, dose distributions for brachytherapy treatments using high-Z shields or having significant material heterogeneities are not currently well modeled using conventional TPS. The purpose of this study is to establish a new treatment planning technique (Tufts technique) that could be applied in some clinical situations where the conventional approach is not acceptable and dose distributions present cylindrical symmetry. Dose distributions from complex brachytherapy source configurations determined with Monte Carlo methods were used as input data. These source distributions included the 2 and 3 cm diameter Valencia skin applicators from Nucletron, 4-8 cm diameter AccuBoost peripheral breast brachytherapy applicators from Advanced Radiation Therapy, and a 16 mm COMS-based eye plaque using {sup 103}Pd, {sup 125}I, and {sup 131}Cs seeds. Radial dose functions and 2D anisotropy functions were obtained by positioning the coordinate system origin along the dose distribution cylindrical axis of symmetry. Origin:tissue distance and active length were chosen to minimize TPS interpolation errors. Dosimetry parameters were entered into the PINNACLE TPS, and dose distributions were subsequently calculated and compared to the original Monte Carlo-derived dose distributions. The new planning technique was able to reproduce brachytherapy dose distributions for all three applicator types, producing dosimetric agreement typically within 2% when compared with Monte Carlo-derived dose distributions. Agreement between Monte Carlo-derived and planned dose distributions improved as the spatial resolution of the fitted dosimetry parameters improved. For agreement within 5% throughout the clinical volume, spatial resolution of

  8. (106)Ruthenium brachytherapy for retinoblastoma.

    Science.gov (United States)

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

    2008-07-01

    To evaluate the efficacy of (106)Ru plaque brachytherapy for the treatment of retinoblastoma. We reviewed a retrospective, noncomparative case series of 39 children with retinoblastoma treated with (106)Ru plaques at the Jules-Gonin Eye Hospital between October 1992 and July 2006, with 12 months of follow-up. A total of 63 tumors were treated with (106)Ru brachytherapy in 41 eyes. The median patient age was 27 months. (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 (106)Ru brachytherapy was used as the first- or second-line treatment and in 15 (31.9%) of 47 tumors for which (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. (106)Ru brachytherapy is an effective treatment for retinoblastoma, with few secondary complications. Local vitreous seeding can be successfully treated with (106)Ru brachytherapy.

  9. SU-E-T-325: Dosimetric Impact Due to FlexiShield in Electronic Brachytherapy (eBx) of Breast IORT: A Phantom Study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y; Huynh, J; Ley, M; Gonzalez, V [University of Arizona, Tucson, AZ (United States)

    2015-06-15

    Purpose: To evaluate dosimetric change of eBx plan due to Flexishield. Methods: To simulate a clinically difficult case (skin spacing < 1 cm and touching chest wall), prostheses breast tissue phantom overlaid Xoft spherical balloon applicator. To minimize significant metal streak artifact, megavoltage CT (MVCT) scan was acquired using helical TomoTherapy HiART. Two sets of MVCT images were taken with/without FlexiShield for 15 cases: 4 for small (3–4 cm), 4 for medium (4–5 cm) and 7 for large (5–6 cm) balloon. Total 30 MVCT scans were obtained with 50 % contrast to improve image contrast of balloon relative to breast tissue phantom. Balloon deformation was measured in anterior-posterior (AP) and lateral (LAT) dimensions in the middle of balloon. Skin spacing was also evaluated. Treatment plan was made based on each MVCT scan and two balloon surface doses (AP and LAT directions) and skin dose were compared between plans with/without FlexiShield. Results: The balloon was deformed due to pressure from both FlexiShield (skin side) and FlexiShield mini (chest wall side). Mean ± standard deviation (maximum) value was 1.5 ± 1.0 mm (3.3 mm) for AP compression and 0.4 ± 0.3 mm (1.1 mm) for LAT expansion. Balloon surface dose was increased by 1.8 ± 1.2 Gy (4.9 Gy) at AP point and decreased by 0.4 ± 0.4 Gy (1.3 Gy) at LAT point. Skin spacing was constantly reduced by 1.1 ± 0.8 mm (3 mm). Skin surface dose was increased by 1.5 ± 0.8 Gy (3.3 Gy) and its relative increase was 17.9 ± 9.3% (39.6%). Conclusion: FlexiShield deforms the balloon and reduces skin spacing, thereby resulting in higher dose in AP direction, lower dose in LAT direction, and elevated skin dose compared to the plan without FlexiShield. In the clinic, this balloon deformation and corresponding dose variation should be considered.

  10. 3D shape shearography with integrated structured light projection for strain inspection of curved objects

    Science.gov (United States)

    Anisimov, Andrei G.; Groves, Roger M.

    2015-05-01

    Shearography (speckle pattern shearing interferometry) is a non-destructive testing technique that provides full-field surface strain characterization. Although real-life objects especially in aerospace, transport or cultural heritage are not flat (e.g. aircraft leading edges or sculptures), their inspection with shearography is of interest for both hidden defect detection and material characterization. Accurate strain measuring of a highly curved or free form surface needs to be performed by combining inline object shape measuring and processing of shearography data in 3D. Previous research has not provided a general solution. This research is devoted to the practical questions of 3D shape shearography system development for surface strain characterization of curved objects. The complete procedure of calibration and data processing of a 3D shape shearography system with integrated structured light projector is presented. This includes an estimation of the actual shear distance and a sensitivity matrix correction within the system field of view. For the experimental part a 3D shape shearography system prototype was developed. It employs three spatially-distributed shearing cameras, with Michelson interferometers acting as the shearing devices, one illumination laser source and a structured light projector. The developed system performance was evaluated with a previously reported cylinder specimen (length 400 mm, external diameter 190 mmm) loaded by internal pressure. Further steps for the 3D shape shearography prototype and the technique development are also proposed.

  11. Programming 2D/3D shape-shifting with hobbyist 3D printers

    NARCIS (Netherlands)

    van Manen, T.; Janbaz, S.; Zadpoor, A.A.

    2017-01-01

    Materials and devices with advanced functionalities often need to combine complex 3D shapes with functionality-inducing surface features. Precisely controlled bio-nanopatterns, printed electronic components, and sensors/actuators are all examples of such surface features. However, the vast majority

  12. Synthesis of image sequences for Korean sign language using 3D shape model

    Science.gov (United States)

    Hong, Mun-Ho; Choi, Chang-Seok; Kim, Chang-Seok; Jeon, Joon-Hyeon

    1995-05-01

    This paper proposes a method for offering information and realizing communication to the deaf-mute. The deaf-mute communicates with another person by means of sign language, but most people are unfamiliar with it. This method enables to convert text data into the corresponding image sequences for Korean sign language (KSL). Using a general 3D shape model of the upper body leads to generating the 3D motions of KSL. It is necessary to construct the general 3D shape model considering the anatomical structure of the human body. To obtain a personal 3D shape model, this general model is to adjust to the personal base images. Image synthesis for KSL consists of deforming a personal 3D shape model and texture-mapping the personal images onto the deformed model. The 3D motions for KSL have the facial expressions and the 3D movements of the head, trunk, arms and hands and are parameterized for easily deforming the model. These motion parameters of the upper body are extracted from a skilled signer's motion for each KSL and are stored to the database. Editing the parameters according to the inputs of text data yields to generate the image sequences of 3D motions.

  13. Breast conserving treatment of breast carcinoma T2 ({<=} 4 cm) and T3 by neoadjuvant chemotherapy, quadrantectomy, high dose rate brachytherapy as a boost, external beam radiotherapy and adjuvant chemotherapy: local control and overall survival analysis; Tratamento conservador do cancer de mama T2 ({<=} 4 cm) e T3 por quimioterapia neoadjuvante, quadrantectomia, braquiterapia com alta taxa de dose como reforco de dose, teleterapia complementar e quimioterapia adjuvante: analise de controle local e sobrevida global

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Celia Regina; Miziara Filho, Miguel Abrao; Fogaroli, Ricardo Cesar; Baraldi, Helena Espindola; Pellizzon, Antonio Cassio Assis; Pelosi, Edilson Lopes [Instituto do Cancer Dr. Arnaldo Vieira de Carvalho (ICAVC), Sao Paulo, SP (Brazil). Servico de Radioterapia], e-mail: celiarsoares@terra.com.br; Fristachi, Carlos Elias [Instituto do Cancer Dr. Arnaldo Vieira de Carvalho (ICAVC), Sao Paulo, SP (Brazil). Servico de Onco-Ginecologia e Mastologia; Paes, Roberto Pinto [Instituto do Cancer Dr. Arnaldo Vieira de Carvalho (ICAVC), Sao Paulo, SP (Brazil)

    2008-12-15

    Objective: to assess the treatment of breast cancer T2 ({<=} 4 cm) and T3 through neoadjuvant chemotherapy, quadrantectomy and high dose rate brachytherapy as a boost, complementary radiotherapy and adjuvant chemotherapy, considering local control and overall survival. Material and method: this clinical prospective descriptive study was based on the evaluation of 88 patients ranging from 30 to 70 years old, with infiltrating ductal carcinoma, clinical stage IIb and IIIa, responsive to the neoadjuvant chemotherapy, treated from June/1995 to December/2006. Median follow-up was 58 months. Using clinical methods the tumor was evaluated before and after three or four cycles of chemotherapy based on anthracyclines. Overall survival and local control were assessed according to Kaplan-Meier methodology. Results: Local control and overall survival in five years were 90% and 73.5%, respectively. Conclusion: local control and overall survival were comparable to other forms of treatment. (author)

  14. Photon Sources for Brachytherapy

    Science.gov (United States)

    Rijnders, Alex

    As introduction a short overview of the history of brachytherapy (BT) is given, with a focus on the evolution in the photon sources that have been used over the years. A major step in this evolution was the introduction of the automatic afterloading devices, which could be compared to the introduction of linear accelerators in external beam radiotherapy (EBRT). The modern afterloaders allow for optimization of the dose delivery and the use of different dose rates (low dose rate, high dose rate and pulsed dose rate) in function of tumor biology and patient comfort. Still today new sources are under investigation, and these developments together with the improvements in treatment planning and treatment techniques will enforce the role and place of BT as a valuable alternative for or supplementary to EBRT.

  15. D-shaped photonic crystal fiber refractive index sensor based on surface plasmon resonance.

    Science.gov (United States)

    An, Guowen; Hao, Xiaopeng; Li, Shuguang; Yan, Xin; Zhang, Xuenan

    2017-08-20

    A type of D-shaped photonic crystal fiber sensor based on surface plasmon resonance (SPR) is proposed for refractive index sensing and analyzed by the finite element method. The SPR effect between surface plasmon polariton modes and fiber core modes of the designed D-shaped photonic crystal fiber is used to measure the refractive index of the analyte. Numerical results show that the sensor can detect a range of refractive index ranging from 1.33 to 1.38. When the thickness of metal film is t=20  nm, the maximum sensitivity of 10,493  nm/RIU is obtained with a very high resolution of 9.53×10(-6)  RIU. The good sensing performance makes the proposed sensor a competitive candidate for environmental, biological, and biochemical sensing applications.

  16. D-shaped tilted fiber Bragg grating using magnetic fluid for magnetic field sensor

    Science.gov (United States)

    Ying, Yu; Zhang, Rui; Si, Guang-Yuan; Wang, Xin; Qi, Yuan-Wei

    2017-12-01

    In our work, a numerical investigation of a magnetic field sensor based on a D-shaped tilted fiber Bragg grating and magnetic fluid is performed. The sensing probe is constructed by placing the magnetic fluid film on the flat surface of the D-shaped tilted fiber Bragg grating. We investigate the resonance wavelengths of the proposed structure with different tilted angles of grating ranging from 0° to 20°, and analyze the magnetic field sensing characteristics. The simulation results show that the optical fiber sensor exhibits optimal transmission characteristics with a tilted angle of 8°. The wavelength sensitivity of the magnetic field sensor is as high as -0.18nm/Oe in the range of 30Oe-270Oe, and it demonstrates a linearity up to R2= -0.9998. Such sensor has potential applications in determining magnetic sensing field.

  17. 3D shape representation with spatial probabilistic distribution of intrinsic shape keypoints

    Science.gov (United States)

    Ghorpade, Vijaya K.; Checchin, Paul; Malaterre, Laurent; Trassoudaine, Laurent

    2017-12-01

    The accelerated advancement in modeling, digitizing, and visualizing techniques for 3D shapes has led to an increasing amount of 3D models creation and usage, thanks to the 3D sensors which are readily available and easy to utilize. As a result, determining the similarity between 3D shapes has become consequential and is a fundamental task in shape-based recognition, retrieval, clustering, and classification. Several decades of research in Content-Based Information Retrieval (CBIR) has resulted in diverse techniques for 2D and 3D shape or object classification/retrieval and many benchmark data sets. In this article, a novel technique for 3D shape representation and object classification has been proposed based on analyses of spatial, geometric distributions of 3D keypoints. These distributions capture the intrinsic geometric structure of 3D objects. The result of the approach is a probability distribution function (PDF) produced from spatial disposition of 3D keypoints, keypoints which are stable on object surface and invariant to pose changes. Each class/instance of an object can be uniquely represented by a PDF. This shape representation is robust yet with a simple idea, easy to implement but fast enough to compute. Both Euclidean and topological space on object's surface are considered to build the PDFs. Topology-based geodesic distances between keypoints exploit the non-planar surface properties of the object. The performance of the novel shape signature is tested with object classification accuracy. The classification efficacy of the new shape analysis method is evaluated on a new dataset acquired with a Time-of-Flight camera, and also, a comparative evaluation on a standard benchmark dataset with state-of-the-art methods is performed. Experimental results demonstrate superior classification performance of the new approach on RGB-D dataset and depth data.

  18. Programming 2D/3D shape-shifting with hobbyist 3D printers

    OpenAIRE

    van Manen, T.; Janbaz, S.; Zadpoor, A.A.

    2017-01-01

    Materials and devices with advanced functionalities often need to combine complex 3D shapes with functionality-inducing surface features. Precisely controlled bio-nanopatterns, printed electronic components, and sensors/actuators are all examples of such surface features. However, the vast majority of the refined technologies that are currently available for creating functional surface features work only on flat surfaces. Here we present initially flat constructs that upon triggering by high ...

  19. American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) practice guideline for the performance of high-dose-rate brachytherapy.

    Science.gov (United States)

    Erickson, Beth A; Demanes, D Jeffrey; Ibbott, Geoffrey S; Hayes, John K; Hsu, I-Chow J; Morris, David E; Rabinovitch, Rachel A; Tward, Jonathan D; Rosenthal, Seth A

    2011-03-01

    High-Dose-Rate (HDR) brachytherapy is a safe and efficacious treatment option for patients with a variety of different malignancies. Careful adherence to established standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and American Society for Therapeutic Radiation Oncology (ASTRO) has produced a practice guideline for HDR brachytherapy. The guideline defines the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrists. Review of the leading indications for HDR brachytherapy in the management of gynecologic, thoracic, gastrointestinal, breast, urologic, head and neck, and soft tissue tumors is presented. Logistics with respect to the brachytherapy implant procedures and attention to radiation safety procedures and documentation are presented. Adherence to these practice guidelines can be part of ensuring quality and safety in a successful HDR brachytherapy program. Copyright © 2011. Published by Elsevier Inc.

  20. 3D shape reconstruction of teeth by shadow speckle correlation method

    Science.gov (United States)

    Gao, Jianxin; Xu, Wei; Geng, Jianping

    2006-05-01

    This paper presents a new method for 3D shape reconstruction in computer-aided dental prosthetics. A specklegram is projected onto the tooth to be measured. This shadow speckle image is recorded and then processed by a digital image correlation method, which enables the computation of 2D shapes based on the similar principle of shadow moiré method. By repeating the procedure for all the sides, i.e., one crown and several side surfaces, local 2D shapes can be measured precisely. Afterwards, these local 2D profiles are merged to form a 3D model, during which certain constraints such as the widths along perpendicular directions are introduced to guide the process. As the height information within an entire image field is recorded instantly, it has the potential to be employed in an intra-oral environment, which would make the patient feel more comfortable during the restoration process. In vitro experiments were carried out on gypsum teeth models and the results proved the effectiveness of the proposed method.

  1. Magnetic resonance image guided brachytherapy.

    Science.gov (United States)

    Tanderup, Kari; Viswanathan, Akila N; Kirisits, Christian; Frank, Steven J

    2014-07-01

    The application of magnetic resonance image (MRI)-guided brachytherapy has demonstrated significant growth during the past 2 decades. Clinical improvements in cervix cancer outcomes have been linked to the application of repeated MRI for identification of residual tumor volumes during radiotherapy. This has changed clinical practice in the direction of individualized dose administration, and resulted in mounting evidence of improved clinical outcome regarding local control, overall survival as well as morbidity. MRI-guided prostate high-dose-rate and low-dose-rate brachytherapies have improved the accuracy of target and organs-at-risk delineation, and the potential exists for improved dose prescription and reporting for the prostate gland and organs at risk. Furthermore, MRI-guided prostate brachytherapy has significant potential to identify prostate subvolumes and dominant lesions to allow for dose administration reflecting the differential risk of recurrence. MRI-guided brachytherapy involves advanced imaging, target concepts, and dose planning. The key issue for safe dissemination and implementation of high-quality MRI-guided brachytherapy is establishment of qualified multidisciplinary teams and strategies for training and education. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Brachytherapy in oesophageal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Leung, J.T.; Kuan, R. [Royal Prince Alfred Hospital, Camperdown, NSW (Australia)

    1995-11-01

    Patients with recurrent or locally advanced oesophageal carcinoma have a poor prognosis. Relief of dysphagia is often the goal of any further treatment. Several methods, including laser re-canalization, prosthetic intubation, dilatation, external beam irradiation (EBI) and intraluminal brachytherapy (IBT) can be used to alleviate dysphagia. In this retrospective review of 11 patients, eight with recurrent tumour and three newly diagnosed patients were treated with low dose rate IBT. Relief of dysphagia was achieved in nine patients, all of whom were able to maintain swallowing of at least a semi-solid diet until death or last follow-up. Toxicity was minimal, but survival was poor, with a median survival of only 3 months. IBT presents several advantages over other palliative methods, especially in recurrent tumours where re-treatment with EBI is often difficult because of normal tissue tolerance. Low dose rate IBT takes only 1-2 days to deliver, is highly effective, has little morbidity and the palliation achieved is relatively durable. 19 refs., 2 tabs., 1 fig.

  3. High-dose-rate interstitial brachytherapy for the treatment of penile carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Petera, J.; Odrazka, K.; Zouhar, M.; Bedrosova, J.; Dolezel, M. [Dept. of Oncology and Radiotherapy, Charles Univ. Medical School and Teaching Hospital, Hradec Kralove (Czech Republic)

    2004-02-01

    Background: interstitial low-dose-rate (LDR) brachytherapy allows conservative treatment of T1-T2 penile carcinoma. High-dose-rate (HDR) is often considered to be dangerous for interstitial implants because of a higher risk of complications, but numerous reports suggest that results may be comparable to LDR. Nevertheless, there are no data in the literature available regarding HDR interstitial brachytherapy for carcinoma of the penis. Case report: a 64-year-old man with T1 NO MO epidermoid carcinoma of the glans is reported. Interstitial HDR brachytherapy was performed using the stainless hollow needle technique and a breast template for fixation and good geometry. The dose delivered was 18 x 3 Gy twice daily. Results: after 232 days from brachytherapy, the patient was without any evidence of the tumor, experienced no serious radiation-induced complications, and had a fully functional organ. Conclusion: HDR interstitial brachytherapy is feasible in selected case of penis carcinoma, when careful planning and small single fractions are used. (orig.)

  4. Brachytherapy dosimeter with silicon photomultipliers

    Energy Technology Data Exchange (ETDEWEB)

    Moutinho, L.M., E-mail: moutinho@ua.pt [i3N, Physics Department, University of Aveiro (Portugal); Castro, I.F.C. [i3N, Physics Department, University of Aveiro (Portugal); Peralta, L. [Faculdade de Ciências da Universidade de Lisboa (Portugal); Laboratório de Instrumentação e Física Experimental de Partículas (LIP), Lisboa (Portugal); Abreu, M.C. [Laboratório de Instrumentação e Física Experimental de Partículas (LIP), Lisboa (Portugal); Veloso, J.F.C.A. [i3N, Physics Department, University of Aveiro (Portugal)

    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.

  5. A D-Shaped Bileaflet Bioprosthesis which Replicates Physiological Left Ventricular Flow Patterns

    Science.gov (United States)

    Tan, Sean Guo-Dong; Kim, Sangho; Hon, Jimmy Kim Fatt; Leo, Hwa Liang

    2016-01-01

    Prior studies have shown that in a healthy heart, there exist a large asymmetric vortex structure that aids in establishing a steady flow field in the left ventricle. However, the implantation of existing artificial heart valves at the mitral position is found to have a negative effect on this physiological flow pattern. In light of this, a novel D-shaped bileaflet porcine bioprosthesis (GD valve) has been designed based on the native geometry mitral valve, with the hypothesis that biomimicry in valve design can restore physiological left ventricle flow patterns after valve implantation. An in-vitro experiment using two dimensional particle velocimetry imaging was carried out to determine the hemodynamic performance of the new bileaflet design and then compared to that of the well-established St. Jude Epic valve which functioned as a control in the experiment. Although both valves were found to have similar Reynolds shear stress and Turbulent Kinetic Energy levels, the novel D-shape valve was found to have lower turbulence intensity and greater mean kinetic energy conservation. PMID:27258099

  6. A D-Shaped Bileaflet Bioprosthesis which Replicates Physiological Left Ventricular Flow Patterns.

    Directory of Open Access Journals (Sweden)

    Sean Guo-Dong Tan

    Full Text Available Prior studies have shown that in a healthy heart, there exist a large asymmetric vortex structure that aids in establishing a steady flow field in the left ventricle. However, the implantation of existing artificial heart valves at the mitral position is found to have a negative effect on this physiological flow pattern. In light of this, a novel D-shaped bileaflet porcine bioprosthesis (GD valve has been designed based on the native geometry mitral valve, with the hypothesis that biomimicry in valve design can restore physiological left ventricle flow patterns after valve implantation. An in-vitro experiment using two dimensional particle velocimetry imaging was carried out to determine the hemodynamic performance of the new bileaflet design and then compared to that of the well-established St. Jude Epic valve which functioned as a control in the experiment. Although both valves were found to have similar Reynolds shear stress and Turbulent Kinetic Energy levels, the novel D-shape valve was found to have lower turbulence intensity and greater mean kinetic energy conservation.

  7. Novel Use of the Contura for High Dose Rate Cranial Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Scanderbeg, Daniel J., E-mail: dscanderbeg@ucsd.edu [Department of Radiation Oncology, University of California at San Diego, La Jolla, CA (United States); Center for Advanced Radiotherapy Technologies, Rebecca and John Moores Comprehensive Cancer Center, University of California at San Diego, La Jolla, CA (United States); Alksne, John F. [Division of Neurological Surgery, University of California at San Diego, La Jolla, CA (United States); Lawson, Joshua D. [Department of Radiation Oncology, University of California at San Diego, La Jolla, CA (United States); Center for Advanced Radiotherapy Technologies, Rebecca and John Moores Comprehensive Cancer Center, University of California at San Diego, La Jolla, CA (United States); Murphy, Kevin T. [Department of Radiation Oncology, University of California at San Diego, La Jolla, CA (United States)

    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.

  8. Rectal complications after prostate brachytherapy.

    Science.gov (United States)

    Shah, Shimul A; Cima, Robert R; Benoit, Eric; Breen, Elizabeth L; Bleday, Ronald

    2004-09-01

    Prostate brachytherapy is gaining wide popularity as an alternative to resection for the treatment of locally advanced prostate cancer. Rectal-urethral fistula after prostate brachytherapy is a rare but serious complication, and its incidence, presentation, risk factors, and clinical management have not been well described. From January 1997 to October 2002, seven patients with rectal-urethral fistulas were referred to two institutions (Brigham and Women's Hospital and West Roxbury Veteran's Administration Hospital) of a major teaching referral center. Clinical presentation, risk factors, prostate staging, and clinical management were examined in a retrospective fashion. Seven rectal-urethral fistulas developed from roughly 700 (1 percent) patients treated with prostate brachytherapy for prostate cancer. The average patient age was 67.7 years, preimplant prostate-specific antigen was 7.1, and Gleason score was 3+3. Symptoms occurred at a mean of 27.3 months after prostate brachytherapy was started and included anorectal pain (57 percent), clear mucous discharge (57 percent), diarrhea (43 percent), and rectal ulceration (43 percent). Coronary artery disease was a common comorbidity (71 percent). Previous transurethral resection of prostate (28 percent) and pelvic irradiation or external beam radiation therapy (14 percent) were not associated with increased risk of rectal-urethral fistula. All patients underwent a diverting colostomy (86 percent) or ileostomy (14 percent), and four patients went on to have definitive therapy. Definitive resection was performed between 5 and 43 months after diverting ostomy and was chosen on the basis of comorbid disease, quality of life, and degree of operation. Two patients required a second diversion after definitive resection because of anorectal pain and a colocutaneous fistula. Postoperative complications included myocardial infarction (14 percent), blood transfusion (14 percent), and bowel perforation (14 percent). Patients

  9. 3D shape measurement of shoeprint impression with structured illumination and fringe pattern analysis

    Science.gov (United States)

    Su, Xianyu; Cao, Yiping; Xiang, Liqun; Chen, Wenjing

    2002-06-01

    The shoeprint impressions of suspect left at the crime scene can sometimes tell investigators what type of shoes to be looked for. These shoeprint impressions as one of the important evidence are useful in the detection of criminals. In this paper we propose a novel technique for identifying and analyzing the 3D characteristics of shoeprint impressions. We also design 3D shoeprint impression analysis system based on the combination the 3D shape measurement with structured illumination and fringe pattern analysis. We give a detail discussion on the principle and configuration of the system. Laboratory experiments show the technique is efficient in the detection of shoeprint and in the offering the reference for judicial evidence.

  10. 3-D shape measurement based on complementary Gray-code light

    Science.gov (United States)

    Zhang, Qican; Su, Xianyu; Xiang, Liqun; Sun, Xuezhen

    2012-04-01

    A combination of phase-shift with Gray-code light projection into a three-dimensional (3-D) measurement system has been exploited to digitalize 3-D shape information of a tested object, even with a discontinuous surface. Unfortunately, the phase unwrapping will fall into an error, when an improper value of Gray coding is caused by mistake at the partial boundary of two adjacent binary words. To this end, a new complementary Gray-code method is proposed in this paper as well as the corresponding phase-unwrapping method. This problem of phase unwrapping could be cleverly solved by projecting an additional Gray-code pattern to extend this code and using the different and complementary boundary locations of the traditional and additional codes. The results of computer simulation and experiment confirm that this proposed method based on complementary Gray-code can reliably reconstruct the nature phase distribution of the tested object with only one extra fringe pattern.

  11. A surface plasmon resonance sensor based on a single mode D-shape polymer optical fiber

    Science.gov (United States)

    Gasior, Katarzyna; Martynkien, Tadeusz; Napiorkowski, Maciej; Zolnacz, Kinga; Mergo, Pawel; Urbanczyk, Waclaw

    2017-02-01

    For the first time to our knowledge, we report a successful fabrication of surface plasmon resonance (SPR) sensors in a specially developed single-mode birefringent polymer D-shape fiber with a core made of PMMA/PS copolymer. A small distance between the core and the cladding boundary allows to deposit a gold layer directly onto the flat fiber surface, which significantly simplifies the sensors fabrication process. The developed SPR sensor exhibits a sensitivity of 2765 nm RIU-1 for the refractive index of external medium equal to 1.410, which is similar to the sensitivity of the SPR sensors based on conventional side-polished single-mode silica fibers. Using the finite element method, we also numerically studied the sensor performance. The sensor characteristics obtained in the simulations are in a relatively good agreement with the experimental results.

  12. Full-field 3D shape measurement of specular object having discontinuous surfaces

    Science.gov (United States)

    Zhang, Zonghua; Huang, Shujun; Gao, Nan; Gao, Feng; Jiang, Xiangqian

    2017-06-01

    This paper presents a novel Phase Measuring Deflectometry (PMD) method to measure specular objects having discontinuous surfaces. A mathematical model is established to directly relate the absolute phase and depth, instead of the phase and gradient. Based on the model, a hardware measuring system has been set up, which consists of a precise translating stage, a projector, a diffuser and a camera. The stage locates the projector and the diffuser together to a known position during measurement. By using the model-based and machine vision methods, system calibration is accomplished to provide the required parameters and conditions. The verification tests are given to evaluate the effectiveness of the developed system. 3D (Three-Dimensional) shapes of a concave mirror and a monolithic multi-mirror array having multiple specular surfaces have been measured. Experimental results show that the proposed method can obtain 3D shape of specular objects having discontinuous surfaces effectively

  13. Quantitative model for the generic 3D shape of ICMEs at 1 AU

    Science.gov (United States)

    Démoulin, P.; Janvier, M.; Masías-Meza, J. J.; Dasso, S.

    2016-10-01

    Context. Interplanetary imagers provide 2D projected views of the densest plasma parts of interplanetary coronal mass ejections (ICMEs), while in situ measurements provide magnetic field and plasma parameter measurements along the spacecraft trajectory, that is, along a 1D cut. The data therefore only give a partial view of the 3D structures of ICMEs. Aims: By studying a large number of ICMEs, crossed at different distances from their apex, we develop statistical methods to obtain a quantitative generic 3D shape of ICMEs. Methods: In a first approach we theoretically obtained the expected statistical distribution of the shock-normal orientation from assuming simple models of 3D shock shapes, including distorted profiles, and compared their compatibility with observed distributions. In a second approach we used the shock normal and the flux rope axis orientations together with the impact parameter to provide statistical information across the spacecraft trajectory. Results: The study of different 3D shock models shows that the observations are compatible with a shock that is symmetric around the Sun-apex line as well as with an asymmetry up to an aspect ratio of around 3. Moreover, flat or dipped shock surfaces near their apex can only be rare cases. Next, the sheath thickness and the ICME velocity have no global trend along the ICME front. Finally, regrouping all these new results and those of our previous articles, we provide a quantitative ICME generic 3D shape, including the global shape of the shock, the sheath, and the flux rope. Conclusions: The obtained quantitative generic ICME shape will have implications for several aims. For example, it constrains the output of typical ICME numerical simulations. It is also a base for studying the transport of high-energy solar and cosmic particles during an ICME propagation as well as for modeling and forecasting space weather conditions near Earth.

  14. Intravascular brachytherapy for peripheral vascular disease

    Directory of Open Access Journals (Sweden)

    Hagen, Anja

    2008-09-01

    Full Text Available Scientific background: Percutaneous transluminal angioplasties (PTA through balloon dilatation with or without stenting, i.e. vessel expansion through balloons with or without of implantation of small tubes, called stents, are used in the treatment of peripheral artery occlusive disease (PAOD. The intravascular vessel irradiation, called intravascular brachytherapy, promises a reduction in the rate of repeated stenosis (rate of restenosis after PTA. Research questions: The evaluation addresses questions on medical efficacy, cost-effectiveness as well as ethic, social and legal implications in the use of brachytherapy in PAOD patients. Methods: A systematic literature search was conducted in August 2007 in the most important medical electronic databases for publications beginning from 2002. The medical evaluation included randomized controlled trials (RCT. The information synthesis was performed using meta-analysis. Health economic modeling was performed with clinical assumptions derived from the meta-analysis and economical assumptions derived from the German Diagnosis Related Groups (G-DRG-2007. Results: Medical evaluation: Twelve publications about seven RCT on brachytherapy vs. no brachytherapy were included in the medical evaluation. Two RCT showed a significant reduction in the rate of restenosis at six and/or twelve months for brachytherapy vs. no brachytherapy after successful balloon dilatation, the relative risk in the meta-analysis was 0.62 (95% CI: 0.46 to 0.84. At five years, time to recurrence of restenosis was significantly delayed after brachytherapy. One RCT showed a significant reduction in the rate of restenosis at six months for brachytherapy vs. no brachytherapy after PTA with optional stenting, the relative risk in the meta-analysis was 0.76 (95% CI: 0.61 to 0.95. One RCT observed a significantly higher rate of late thrombotic occlusions after brachytherapy in the subgroup of stented patients. A single RCT for brachytherapy

  15. Contribution of disparity to the perception of 3D shape as revealed by bistability of stereoscopic Necker cubes.

    Science.gov (United States)

    Erkelens, C J

    2012-01-01

    The Necker cube is a famous demonstration of ambiguity in visual perception of 3D shape. Its bistability is attributed to indecisiveness because monocular cues do not allow the observer to infer one particular 3D shape from the 2D image. A remarkable but not appreciated observation is that Necker cubes are bistable during binocular viewing. One would expect disparity information to veto bistability. To investigate the effect of zero and non-zero disparity on perceptual bistability in detail, perceptual dominance durations were measured for luminance- and disparity-defined Necker cubes. Luminance-defined Necker cubes were bistable for all tested disparities between the front and back faces of the cubes. Absence of an effect of disparity on dominance durations suggested the suppression of disparity information. Judgments of depth between the front and back sides of the Necker cubes, however, showed that disparity affected perceived depth. Disparity-defined Necker cubes were also bistable but dominance durations showed different distributions. I propose a framework for 3D shape perception in which 3D shape is inferred from pictorial cues acting on luminance- and disparity-defined 2D shapes.

  16. Afterloading: The Technique That Rescued Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Aronowitz, Jesse N., E-mail: jesse.aronowitz@umassmemorial.org

    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.

  17. Intraoperative HDR Brachytherapy: Present and Future

    NARCIS (Netherlands)

    I.-K.K. Kolkman-Deurloo (Inger-Karina)

    2007-01-01

    textabstractRadiotherapy is one of the most effective modalities in cancer treatment, and can be applied either by external beam radiotherapy or by brachytherapy. Brachytherapy is a treatment modality in which tumors are irradiated by positioning radioactive sources very close to or in the tumor

  18. Image-Based Biomarker of Breast Cancer Risk: Analysis of Risk Disparity Among Minority Populations

    Science.gov (United States)

    2011-03-01

    brachytherapy , and other special techniques. ------------------------------------------------------------------------------------ DSUPENN Breast...simulated skin and Cooper’s ligaments. We designed and implemented the new method in Matlab and analyzed its asymptotic spatial and temporal complexity. We

  19. Dynamic rotating-shield brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yunlong [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 (United States); Flynn, Ryan T.; Kim, Yusung [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Yang, Wenjun [Department of Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Madison, Wisconsin 53705 (United States); Wu, Xiaodong [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 and Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States)

    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

  20. MRT letter: a total variation based method for 3D shape recovery of microscopic objects through image focus.

    Science.gov (United States)

    Mahmood, Muhammad Tariq

    2013-09-01

    Generally, shape from focus methods use a single focus measure to compute focus quality and to obtain an initial depth map of an object. However, different focus measures perform differently in diverse conditions. Therefore, it is hard to get accurate 3D shape based on a single focus measure. In this article, we propose a total variation based method for recovering 3D shape of an object by combining multiple depth hypothesis obtained through different focus measures. Improved performance of the proposed method is evaluated by conducting several experiments using images of synthetic and real microscopic objects. Comparative analysis demonstrates the effectiveness of the proposed approach. Copyright © 2013 Wiley Periodicals, Inc.

  1. Quantification of lacrimal function after D-shaped field irradiation for retinoblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Imhof, S.M.; Tan, K.E.W.P. (Free Univ. Hospital, Amsterdam (Netherlands). Dept. of Ophthalmology); Hofman, P. (Utrecht Univ. Hospital (Netherlands). Dept. of Radiotherapy)

    1993-08-01

    To study the quantitative effects of mega-voltage external beam irradiation in a D-shaped field in patients with retinoblastoma, biomicroscopy was performed in 61 patients and tear function tests (Schirmer-lactoferrin and lysozyme tests) on 45 eyes in 34 irradiated patients. The results were compared with those obtained in 25 non-irradiated control eyes. The Schirmer test was significantly diminished in irradiated eyes, as were the lactoferrin and lysozyme values. A mild to severe keratitis was found in 17 of the 61 patients (28%). A significant correlation (p<0.005) was found between the severe keratitis and the mean Schirmer values; the mean lactoferrin and lysozyme values were diminished in all patients but did not correlate significantly with the corneal abnormalities. These quantitative data, obtained in patients treated for retinoblastoma, affirm the qualitative data found in patients irradiated for other reasons such as orbital or sinus tumours. Irradiation for retinoblastoma is not a harmless treatment and serious late side effects have to be considered. (Author).

  2. Whole 3D shape reconstruction of vascular segments under pressure via fringe projection techniques

    Science.gov (United States)

    Genovese, Katia; Pappalettere, Carmine

    2006-12-01

    Understanding and modelling vascular wall mechanics is a primary issue in the study of circulatory diseases. Although theoretical and numerical studies on arteries compliance are continuously increasing, relatively little work has been documented on the use of non-invasive imaging techniques for monitoring 3D vascular wall deformations. Usually, 2D video dimension analyzer (VDA) systems recover diameter and length variations during inflation/extension tests by tracking position changes of few markers put on the blood vessel surface. Then, strain determination relies on the assumption of axisymmetric deformations. However, more rigorous evaluations of whole wall deformation map are required for properly modelling the highly anisotropic and inhomogeneous vascular tissue mechanical response. This paper describes the development and application of a fringe projection (FP)-based procedure for the 360° 3D shape reconstruction of tubular samples subjected to internal pressure. A specially designed fixture for mounting and inflating the tubular segment allows specimen rotation about its axis. Movement is controlled by a high-precision rotational stage. This yields accurate positioning of the surface to be investigated with respect to the viewing direction. Data point clouds obtained from multiple recorded images are then processed and merged in a CAD environment, thus providing the whole shape of the sample with very high spatial resolution. The entire procedure has successfully been applied to latex specimens and porcine vascular segments. Further improvements will make the present procedure suitable for in vitro tests under more closely reproduced physiological conditions.

  3. Reducing the pressure drag of a D-shaped bluff body using linear feedback control

    Science.gov (United States)

    Dalla Longa, L.; Morgans, A. S.; Dahan, J. A.

    2017-12-01

    The pressure drag of blunt bluff bodies is highly relevant in many practical applications, including to the aerodynamic drag of road vehicles. This paper presents theory revealing that a mean drag reduction can be achieved by manipulating wake flow fluctuations. A linear feedback control strategy then exploits this idea, targeting attenuation of the spatially integrated base (back face) pressure fluctuations. Large-eddy simulations of the flow over a D-shaped blunt bluff body are used as a test-bed for this control strategy. The flow response to synthetic jet actuation is characterised using system identification, and controller design is via shaping of the frequency response to achieve fluctuation attenuation. The designed controller successfully attenuates integrated base pressure fluctuations, increasing the time-averaged pressure on the body base by 38%. The effect on the flow field is to push the roll-up of vortices further downstream and increase the extent of the recirculation bubble. This control approach uses only body-mounted sensing/actuation and input-output model identification, meaning that it could be applied experimentally.

  4. Statistical 3D shape analysis of gender differences in lateral ventricles

    Science.gov (United States)

    He, Qing; Karpman, Dmitriy; Duan, Ye

    2010-03-01

    This paper aims at analyzing gender differences in the 3D shapes of lateral ventricles, which will provide reference for the analysis of brain abnormalities related to neurological disorders. Previous studies mostly focused on volume analysis, and the main challenge in shape analysis is the required step of establishing shape correspondence among individual shapes. We developed a simple and efficient method based on anatomical landmarks. 14 females and 10 males with matching ages participated in this study. 3D ventricle models were segmented from MR images by a semiautomatic method. Six anatomically meaningful landmarks were identified by detecting the maximum curvature point in a small neighborhood of a manually clicked point on the 3D model. Thin-plate spline was used to transform a randomly selected template shape to each of the rest shape instances, and the point correspondence was established according to Euclidean distance and surface normal. All shapes were spatially aligned by Generalized Procrustes Analysis. Hotelling T2 twosample metric was used to compare the ventricle shapes between males and females, and False Discovery Rate estimation was used to correct for the multiple comparison. The results revealed significant differences in the anterior horn of the right ventricle.

  5. Two conformational states in D-shaped DNA: Effects of local denaturation

    Science.gov (United States)

    Lee, O.-Chul; Kim, Cheolhee; Kim, Jae-Yeol; Lee, Nam Ki; Sung, Wokyung

    2016-06-01

    The bending of double-stranded(ds) DNA on the nano-meter scale plays a key role in many cellular processes such as nucleosome packing, transcription-control, and viral-genome packing. In our recent study, a nanometer-sized dsDNA bent into a D shape was formed by hybridizing a circular single-stranded(ss) DNA and a complementary linear ssDNA. Our fluorescence resonance energy transfer (FRET) measurement of D-DNA revealed two types of conformational states: a less-bent state and a kinked state, which can transform into each other. To understand the origin of the two deformed states of D-DNA, here we study the presence of open base-pairs in the ds portion by using the breathing-DNA model to simulate the system. We provide strong evidence that the two states are due to the emergence of local denaturation, i.e., a bubble in the middle and two forks at ends of the dsDNA portion. We also study the system analytically and find that the free-energy landscape is bistable with two minima representative of the two states. The kink and fork sizes estimated by the analytical calculation are also in excellent agreement with the results of the simulation. Thus, this combined experimental-simulation-analytical study corroborates that highly bent D-DNA reduces bending stress via local denaturation.

  6. Drag of a D-shaped bluff body under small amplitude harmonic actuation

    Directory of Open Access Journals (Sweden)

    Yaqing Li

    2015-01-01

    Full Text Available Open-loop flow control method was used to affect the development of a turbulent wake behind a D-shaped bluff body. Loud speakers were embedded inside the bluff body to produce two zero-net-mass-flux jets through 2 mm-wide span-wise slots located along the upper and lower edges on the rear wall. The drag forces for different actuation amplitudes (Cμ, the ratio between the momentum of the actuating jets and the moment deficit caused by the bluff body and frequencies (StA were examined. The effects of the phase difference in the two jets (0 and π were also studied. It was found that when Cμ was 0.1%, a drag reduction up to 5% was achieved when the velocities of the two jets varied in phase at a frequency of StA=0.16. When the velocities of the two jets varied π out of phase, significant drag increase was observed.

  7. Lung lobe segmentation by graph search with 3D shape constraints

    Science.gov (United States)

    Zhang, Li; Hoffman, Eric A.; Reinhardt, Joseph M.

    2001-05-01

    The lung lobes are natural units for reporting image-based measurements of the respiratory system. Lobar segmentation can also be used in pulmonary image processing to guide registration and drive additional segmentation. We have developed a 3D shape-constrained lobar segmentation technique for volumetric pulmonary CT images. The method consists of a search engine and shape constraints that work together to detect lobar fissures using gray level information and anatomic shape characteristics in two steps: (1) a coarse localization step, (2) a fine tuning step. An error detecting mechanism using shape constraints is used in our method to correct erroneous search results. Our method has been tested in four subjects, and the results are compared to manually traced results. The average RMS difference between the manual results and shape-constrained segmentation results is 2.23 mm. We further validated our method by evaluating the repeatability of lobar volumes measured from repeat scans of the same subject. We compared lobar air and tissue volume variations to show that most of the lobar volume variations are due to difference in air volume scan to scan.

  8. Research on High Sensitive D-Shaped FBG Hydrogen Sensors in Power Transformer Oil.

    Science.gov (United States)

    Luo, Ying-Ting; Wang, Hong-Bin; Ma, Guo-Ming; Song, Hong-Tu; Li, Chengrong; Jiang, Jun

    2016-10-04

    Dissolved hydrogen is a symbol gas decomposed by power transformer oil for electrical faults such as overheat or partial discharges. A novel D-shaped fiber Bragg grating (D-FBG) sensor is herein proposed and was fabricated with magnetron sputtering to measure the dissolved hydrogen concentration in power transformer oil in this paper. Different from the RI (refractive index)-based effect, D-FBG in this case is sensitive to curvature caused by stress from sensing coating, leading to Bragg wavelength shifts accordingly. The relationship between the D-FBG wavelength shift and dissolved hydrogen concentration in oil was measured experimentally in the laboratory. The detected sensitivity could be as high as 1.96 μL/L at every 1-pm wavelength shift. The results proved that a simple, polished FBG-based hydrogen sensor provides a linear measuring characteristic in the range of low hydrogen concentrations in transformer oil. Moreover, the stable hydrogen sensing performance was investigated by X-ray diffraction analysis.

  9. KOALA: 3-D shape of asteroids from multi-data inversion

    Science.gov (United States)

    Carry, B.; Kaasalainen, M.; Merline, W. J.; Drummond, J. D.; Durech, J.; Berthier, J.; Conrad, A.

    2011-10-01

    We describe our on-going observing program to determine the physical properties of asteroids from groundbased facilities. We combine disk-resolved images from adaptive optics, optical lightcurves, and stellar occultations to put tighter constraints on the spin, 3-D shape, and size of asteroids. We will discuss the relevance of the determination of physical properties to help understand the asteroid population (e.g., density, composition, and non-gravitational forces). We will then briefly describe our multi-data inversion algorithm KOALA (Carry et al. 2010a, Kaasalainen 2011, see also Kaasalainen et al., same meeting), which allows the determination of certain physical properties of an asteroid from the combination of different techniques of observation. A comparison of results obtained with KOALA on asteroid (21) Lutetia, prior to the ESA Rosetta flyby, with the high spatial resolution images returned from that flyby, will then be presented, showing the high accuracy of KOALA inversion. Finally, we will describe our current development of the algorithm, and focus on examples of other asteroids currently being studied with KOALA.

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

    OpenAIRE

    Pons-Llanas, Olga; Ballester-S?nchez, Rosa; Celada-?lvarez, Francisco Javier; Candela-Juan, Cristian; Garc?a-Mart?nez, Teresa; Llavador-Ros, Margarita; Botella-Estrada, Rafael; Barker, Christopher A.; Ballesta, Antonio; Tormo-Mic?, Alejandro; Rodr?guez, Silvia; Perez-Calatayud, Jose

    2014-01-01

    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 applic...

  11. Object Recognition in Flight: How Do Bees Distinguish between 3D Shapes?

    Directory of Open Access Journals (Sweden)

    Annette Werner

    Full Text Available Honeybees (Apis mellifera discriminate multiple object features such as colour, pattern and 2D shape, but it remains unknown whether and how bees recover three-dimensional shape. Here we show that bees can recognize objects by their three-dimensional form, whereby they employ an active strategy to uncover the depth profiles. We trained individual, free flying honeybees to collect sugar water from small three-dimensional objects made of styrofoam (sphere, cylinder, cuboids or folded paper (convex, concave, planar and found that bees can easily discriminate between these stimuli. We also tested possible strategies employed by the bees to uncover the depth profiles. For the card stimuli, we excluded overall shape and pictorial features (shading, texture gradients as cues for discrimination. Lacking sufficient stereo vision, bees are known to use speed gradients in optic flow to detect edges; could the bees apply this strategy also to recover the fine details of a surface depth profile? Analysing the bees' flight tracks in front of the stimuli revealed specific combinations of flight maneuvers (lateral translations in combination with yaw rotations, which are particularly suitable to extract depth cues from motion parallax. We modelled the generated optic flow and found characteristic patterns of angular displacement corresponding to the depth profiles of our stimuli: optic flow patterns from pure translations successfully recovered depth relations from the magnitude of angular displacements, additional rotation provided robust depth information based on the direction of the displacements; thus, the bees flight maneuvers may reflect an optimized visuo-motor strategy to extract depth structure from motion signals. The robustness and simplicity of this strategy offers an efficient solution for 3D-object-recognition without stereo vision, and could be employed by other flying insects, or mobile robots.

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

    Science.gov (United States)

    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.

  13. Sensor for In-Motion Continuous 3D Shape Measurement Based on Dual Line-Scan Cameras

    Directory of Open Access Journals (Sweden)

    Bo Sun

    2016-11-01

    Full Text Available The acquisition of three-dimensional surface data plays an increasingly important role in the industrial sector. Numerous 3D shape measurement techniques have been developed. However, there are still limitations and challenges in fast measurement of large-scale objects or high-speed moving objects. The innovative line scan technology opens up new potentialities owing to the ultra-high resolution and line rate. To this end, a sensor for in-motion continuous 3D shape measurement based on dual line-scan cameras is presented. In this paper, the principle and structure of the sensor are investigated. The image matching strategy is addressed and the matching error is analyzed. The sensor has been verified by experiments and high-quality results are obtained.

  14. Evanescent-coupling fiber optic pollution monitoring system using etched D-shape E-core fiber

    Science.gov (United States)

    Lee, Shing M.; Yang, Changjie; Pan, Wei P.

    1996-12-01

    Surface contamination of insulators in high voltage transmission and distribution systems may lead to troublesome flashovers which interrupt service. Insulator contamination may be monitored using direct measurement of equivalent salt deposit density (ESDD), which directly relates to the flashover voltage. A fiber-optic evanescent- coupling fiber-optic ESDD monitor is presented. The use of a piece of D-shape E-core fiber as sensor head can provide a sensitive and large area ESDD monitoring system. We have demonstrated the use of D-shape fiber in monitoring ESDD on insulator surfaces. A simple process has been developed to precisely etch the D-fiber. The polarimetric and evanescent loss sensors have been investigated. The evanescent loss sensor is particularly suitable for in-situ ESDD monitoring in power transmission lines and substations.

  15. Novel D-shaped fiber fabrication method for saturable absorber application in the generation of ultra-short pulses

    Science.gov (United States)

    Ahmad, H.; Safaei, R.; Rezayi, M.; Amiri, I. S.

    2017-08-01

    A cost-efficient, time-saving and effective technique for the fabrication of D-shaped fibers is presented, to provide a platform with a strong evanescent field to be used as a saturable absorber (SA). This technique provides flexibility by removing the required portion of the fiber, and a small polished length which offers a unique opportunity to deposit SA on its surface by simply submerging it in the SA solution without high losses. A compact fiber laser utilizing a graphene oxide coating on a fabricated D-shaped fiber as an SA capable of generating ultrashort pulses is designed and verified. We report the generation of ultrafast pulses as short as 227 fs with a 34.7 MHz repetition rate, having a 3 dB bandwidth of 14 nm at the 1570 nm center wavelength.

  16. Simultaneous acquisition of 3D shape and deformation by combination of interferometric and correlation-based laser speckle metrology.

    Science.gov (United States)

    Dekiff, Markus; Berssenbrügge, Philipp; Kemper, Björn; Denz, Cornelia; Dirksen, Dieter

    2015-12-01

    A metrology system combining three laser speckle measurement techniques for simultaneous determination of 3D shape and micro- and macroscopic deformations is presented. While microscopic deformations are determined by a combination of Digital Holographic Interferometry (DHI) and Digital Speckle Photography (DSP), macroscopic 3D shape, position and deformation are retrieved by photogrammetry based on digital image correlation of a projected laser speckle pattern. The photogrammetrically obtained data extend the measurement range of the DHI-DSP system and also increase the accuracy of the calculation of the sensitivity vector. Furthermore, a precise assignment of microscopic displacements to the object's macroscopic shape for enhanced visualization is achieved. The approach allows for fast measurements with a simple setup. Key parameters of the system are optimized, and its precision and measurement range are demonstrated. As application examples, the deformation of a mandible model and the shrinkage of dental impression material are measured.

  17. 3D base: a geometrical data base system for the analysis and visualisation of 3D-shapes obtained from parallel serial sections including three different geometrical representations

    NARCIS (Netherlands)

    Verbeek, F. J.; de Groot, M. M.; Huijsmans, D. P.; Lamers, W. H.; Young, I. T.

    1993-01-01

    In this paper we discuss a geometrical data base that includes three different geometrical representations of one and the same reconstructed 3D shape: the contour-pile, the voxel enumeration, and the triangulation of a surface. The data base is tailored for 3D shapes obtained from plan-parallel

  18. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Science.gov (United States)

    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 a...

  19. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Science.gov (United States)

    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 a...

  20. 10 CFR 35.2406 - Records of brachytherapy source accountability.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Records of brachytherapy source accountability. 35.2406... Records of brachytherapy source accountability. (a) A licensee shall maintain a record of brachytherapy source accountability required by § 35.406 for 3 years. (b) For temporary implants, the record must...

  1. 10 CFR 35.406 - Brachytherapy sources accountability.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Brachytherapy sources accountability. 35.406 Section 35....406 Brachytherapy sources accountability. (a) A licensee shall maintain accountability at all times... area. (c) A licensee shall maintain a record of the brachytherapy source accountability in accordance...

  2. Development of a Remote Handling Robot for the Maintenance of an ITER-Like D-Shaped Vessel

    Directory of Open Access Journals (Sweden)

    Peihua Chen

    2014-01-01

    Full Text Available Robotic operation is one of the major challenges in the remote maintenance of ITER vacuum vessel (VV and future fusion reactors as inner operations of Tokamak have to be done by robots due to the internal adverse conditions. This paper introduces a novel remote handling robot (RHR for the maintenance of ITER-like D-shaped vessel. The modular designed RHR, which is an important part of the remote handling system for ITER, consists of three parts: an omnidirectional transfer vehicle (OTV, a planar articulated arm (PAA, and an articulated teleoperated manipulator (ATM. The task of RHR is to carry processing tools, such as the viewing system, leakage detector, and electric screwdriver, to inspect and maintain the components installed inside the D-shaped vessel. The kinematics of the OTV, as well as the kinematic analyses of the PAA and ATM, is studied in this paper. Because of its special length and heavy payload, the dynamics of the PAA is also investigated through a dynamic simulation system based on robot technology middleware (RTM. The results of the path planning, workspace simulations, and dynamic simulation indicate that the RHR has good mobility together with satisfying kinematic and dynamic performances and can well accomplish its maintenance tasks in the ITER-like D-shaped vessel.

  3. Double-pattern triangular pulse width modulation technique for high-accuracy high-speed 3D shape measurement.

    Science.gov (United States)

    Wang, Yajun; Jiang, Chufan; Zhang, Song

    2017-11-27

    Using 1-bit binary patterns for three-dimensional (3D) shape measurement has been demonstrated as being advantageous over using 8-bit sinusoidal patterns in terms of achievable speeds. However, the phase quality generated by binary pattern(s) typically are not high if only a small number of phase-shifted patterns are used. This paper proposes a method to improve the phase quality by representing each pattern with the difference of two binary patterns: the first binary pattern is generated by triangular pulse width modulation (TPWM) technique, and the second being π shifted from the first pattern that is also generated by TPWM technique. The phase is retrieved by applying a three-step phase-shifting algorithm to the difference patterns. Through optimizing the modulation frequency of the triangular carrier signal, we demonstrate that a high-quality phase can be generated for a wide range of fringe periods (e.g., from 18 to 1140 pixels) with only six binary patterns. Since only 1-bit binary patterns are required for 3D shape measurement, this paper will present a real-time 3D shape measurement system that can achieve 30 Hz.

  4. In vivo dosimetry in brachytherapy.

    Science.gov (United States)

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

    2013-07-01

    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.

  5. In vivo dosimetry in brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Tanderup, Kari [Department of Oncology, Aarhus University Hospital, Aarhus 8000 (Denmark); Department of Clinical Medicine, Aarhus University, Aarhus 8000 (Denmark); Beddar, Sam [Department of Radiation Oncology, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Andersen, Claus E.; Kertzscher, Gustavo [Center of Nuclear Technologies, Technical University of Denmark, Roskilde 4000 (Denmark); Cygler, Joanna E. [Department of Physics, Ottawa Hospital Cancer Centre, Ottawa, Ontario K1H 8L6 (Canada)

    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.

  6. Patient-Specific Monte Carlo-Based Dose-Kernel Approach for Inverse Planning in Afterloading Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    D' Amours, Michel [Departement de Radio-Oncologie et Centre de Recherche en Cancerologie de l' Universite Laval, Hotel-Dieu de Quebec, Quebec, QC (Canada); Department of Physics, Physics Engineering, and Optics, Universite Laval, Quebec, QC (Canada); Pouliot, Jean [Department of Radiation Oncology, University of California, San Francisco, School of Medicine, San Francisco, CA (United States); Dagnault, Anne [Departement de Radio-Oncologie et Centre de Recherche en Cancerologie de l' Universite Laval, Hotel-Dieu de Quebec, Quebec, QC (Canada); Verhaegen, Frank [Department of Radiation Oncology, Maastro Clinic, GROW Research Institute, Maastricht University Medical Centre, Maastricht (Netherlands); Department of Oncology, McGill University, Montreal, QC (Canada); Beaulieu, Luc, E-mail: beaulieu@phy.ulaval.ca [Departement de Radio-Oncologie et Centre de Recherche en Cancerologie de l' Universite Laval, Hotel-Dieu de Quebec, Quebec, QC (Canada); Department of Physics, Physics Engineering, and Optics, Universite Laval, Quebec, QC (Canada)

    2011-12-01

    Purpose: Brachytherapy planning software relies on the Task Group report 43 dosimetry formalism. This formalism, based on a water approximation, neglects various heterogeneous materials present during treatment. Various studies have suggested that these heterogeneities should be taken into account to improve the treatment quality. The present study sought to demonstrate the feasibility of incorporating Monte Carlo (MC) dosimetry within an inverse planning algorithm to improve the dose conformity and increase the treatment quality. Methods and Materials: The method was based on precalculated dose kernels in full patient geometries, representing the dose distribution of a brachytherapy source at a single dwell position using MC simulations and the Geant4 toolkit. These dose kernels are used by the inverse planning by simulated annealing tool to produce a fast MC-based plan. A test was performed for an interstitial brachytherapy breast treatment using two different high-dose-rate brachytherapy sources: the microSelectron iridium-192 source and the electronic brachytherapy source Axxent operating at 50 kVp. Results: A research version of the inverse planning by simulated annealing algorithm was combined with MC to provide a method to fully account for the heterogeneities in dose optimization, using the MC method. The effect of the water approximation was found to depend on photon energy, with greater dose attenuation for the lower energies of the Axxent source compared with iridium-192. For the latter, an underdosage of 5.1% for the dose received by 90% of the clinical target volume was found. Conclusion: A new method to optimize afterloading brachytherapy plans that uses MC dosimetric information was developed. Including computed tomography-based information in MC dosimetry in the inverse planning process was shown to take into account the full range of scatter and heterogeneity conditions. This led to significant dose differences compared with the Task Group report

  7. Patient-specific Monte Carlo-based dose-kernel approach for inverse planning in afterloading brachytherapy.

    Science.gov (United States)

    D'Amours, Michel; Pouliot, Jean; Dagnault, Anne; Verhaegen, Frank; Beaulieu, Luc

    2011-12-01

    Brachytherapy planning software relies on the Task Group report 43 dosimetry formalism. This formalism, based on a water approximation, neglects various heterogeneous materials present during treatment. Various studies have suggested that these heterogeneities should be taken into account to improve the treatment quality. The present study sought to demonstrate the feasibility of incorporating Monte Carlo (MC) dosimetry within an inverse planning algorithm to improve the dose conformity and increase the treatment quality. The method was based on precalculated dose kernels in full patient geometries, representing the dose distribution of a brachytherapy source at a single dwell position using MC simulations and the Geant4 toolkit. These dose kernels are used by the inverse planning by simulated annealing tool to produce a fast MC-based plan. A test was performed for an interstitial brachytherapy breast treatment using two different high-dose-rate brachytherapy sources: the microSelectron iridium-192 source and the electronic brachytherapy source Axxent operating at 50 kVp. A research version of the inverse planning by simulated annealing algorithm was combined with MC to provide a method to fully account for the heterogeneities in dose optimization, using the MC method. The effect of the water approximation was found to depend on photon energy, with greater dose attenuation for the lower energies of the Axxent source compared with iridium-192. For the latter, an underdosage of 5.1% for the dose received by 90% of the clinical target volume was found. A new method to optimize afterloading brachytherapy plans that uses MC dosimetric information was developed. Including computed tomography-based information in MC dosimetry in the inverse planning process was shown to take into account the full range of scatter and heterogeneity conditions. This led to significant dose differences compared with the Task Group report 43 approach for the Axxent source. Copyright © 2011

  8. Dosimetric study of a brachytherapy treatment of esophagus with Brazilian 192Ir sources using an anthropomorphic phantom

    Science.gov (United States)

    Neves, Lucio P.; Santos, William S.; Gorski, Ronan; Perini, Ana P.; Maia, Ana F.; Caldas, Linda V. E.; Orengo, Gilberto

    2014-11-01

    Several radioisotopes are produced at Instituto de Pesquisas Energéticas e Nucleares for the use in medical treatments, including the activation of 192Ir sources. These sources are suitable for brachytherapy treatments, due to their low or high activity, depending on the concentration of 192Ir, easiness to manufacture, small size, stable daughter products and the possibility of re-utilization. They may be used for the treatment of prostate, cervix, head and neck, skin, breast, gallbladder, uterus, vagina, lung, rectum, and eye cancer treatment. In this work, the use of some 192Ir sources was studied for the treatment of esophagus cancer, especially the dose determination of important structures, such as those on the mediastinum. This was carried out utilizing a FASH anthropomorphic phantom and the MCNP5 Monte Carlo code to transport the radiation through matter. It was possible to observe that the doses at lungs, breast, esophagus, thyroid and heart were the highest, which was expected due to their proximity to the source. Therefore, the data are useful to assess the representative dose specific to brachytherapy treatments on the esophagus for radiation protection purposes. The use of brachytherapy sources was studied for the treatment of esophagus cancer. FASH anthropomorphic phantom and MCNP5 Monte Carlo code were employed. The doses at lungs, breast, esophagus, thyroid and heart were the highest. The data is useful to assess the representative doses of treatments on the esophagus.

  9. Brachytherapy

    Science.gov (United States)

    ... type of energy, called ionizing radiation, to kill cancer cells and shrink tumors. External beam radiation therapy (EBRT) involves high-energy ... a grain of rice) in or near the tumor and leaving them there permanently. ... the radioactivity level of the implants eventually diminishes to nothing. ...

  10. Brachytherapy with an improved MammoSite Radiation Therapy System

    Science.gov (United States)

    Karthik, Nanda; Keppel, Cynthia; Nazaryan, Vahagn

    2007-03-01

    Accelerated partial breast irradiation treatment utilizing the MammoSite Radiation Therapy System (MRTS) is becoming increasingly popular. Clinical studies show excellent results for disease control and localization, as well as for cosmesis. Several Phase I, II, and III clinical trials have found significant association between skin spacing and cosmetic results after treatment with MRTS. As a result, patients with skin spacing less then 7 mm are not recommended to undergo this treatment. We have developed a practical innovation to the MammoSite brachytherapy methodology that is directed to overcome the skin spacing problem. The idea is to partially shield the radiation dose to the skin where the skin spacing is less then 7 mm, thereby protecting the skin from radiation damage. Our innovation to the MRTS will allow better cosmetic outcome in breast conserving therapy (BCT), and will furthermore allow more women to take advantage of BCT. Reduction in skin radiation exposure is particularly important for patients also undergoing adjuvant chemotherapy. We will present the method and preliminary laboratory and Monte Carlo simulation results.

  11. Combined anti-tumor therapeutic effect of targeted gene, hyperthermia, radionuclide brachytherapy in breast carcinoma%磁感应加热和HSV-tk自杀基因及核素内照射联合治疗乳腺癌的实验研究

    Institute of Scientific and Technical Information of China (English)

    陈道桢; 唐秋莎; 项静英; 许飞; 张立; 王峻峰

    2011-01-01

    素治疗能有效抑制MCF-7乳腺癌的生长,对乳腺癌治疗有潜在的应用前景.%Objective To investigate the antitumor therapeutic effect of combined therapy of magnetic induction heating by nano-magnetic particles, herpes simplex virus thymidine kinase gene(HSV-tk suicide gene) and internal radiation in mice bearing MCF-7 breast carcinoma. Methods The transfection reagents, plasmids heat shock protein-HSV-tk (pHSP-HSV-tk), ferroso-ferric oxide nano-magnetic fluid flow and 188Re-ganciclovir-bovine serum albumin-nanopaticles (GCV-BSA-NP) were prepared. The heating experiments in vivo were carried out using ferroso-ferric oxide nano-magnetic fluid flow. Sixty mice tumor models bearing MCF-7 breast carcinoma were established and randomly divided into six groups. Group A was the control group, B was gene transfection therapy group, C was hyperthermia group, D was gene transfection therapy combined with radionuclide brachytherapy group, E was gene therapy combined with hyperthermia group, and F was gene therapy, hyperthermia combined with radionuclide brachytherapy group. The tumor growth, tumor mass and histopathological changes were evaluated. The expression of HSV-tk in the groups of B, D, E and F was detected by RT-PCR. Poisson distribution and one-way analysis of variance (ANOVA) were used for statistical analysis by SPSS 10.0 software. Results In the animal heating experiments, the temperature of tumor increased up to 39.6 ℃, 43.2 ℃, and 48.1 ℃ quickly with different injected doses (2, 4 and 6 mg respectively) of nano-magnetic particles and maintained for 40 min. The temperature of tumor tissue reduced to 36.8 ℃, 37.5 ℃ and 37.8 ℃ in 10 min when alternating magnetic field (AMF) stopped. The tumor mass in Groups C ((452.50 ±30.29) mg), D ((240.98 ±35.32)mg), E((231.87 ±27.41) mg) and F ((141.55 ±23.78) mg) were much lower than that in Group A ((719.12±22.65) mg) (F=800.07, P<0. 01), with the most significant treatment effect in Group F.The tumor mass in Group B

  12. Sensitivity of low energy brachytherapy Monte Carlo dose calculations to uncertainties in human tissue composition

    Energy Technology Data Exchange (ETDEWEB)

    Landry, Guillaume; Reniers, Brigitte; Murrer, Lars; Lutgens, Ludy; Bloemen-Van Gurp, Esther; Pignol, Jean-Philippe; Keller, Brian; Beaulieu, Luc; Verhaegen, Frank [Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands); Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Departement de Radio-Oncologie et Centre de Recherche en Cancerologie, de l' Universite Laval, CHUQ, Pavillon L' Hotel-Dieu de Quebec, Quebec G1R 2J6 (Canada) and Departement de Physique, de Genie Physique et d' Optique, Universite Laval, Quebec G1K 7P4 (Canada); Department of Radiation Oncology (MAASTRO), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands) and Medical Physics Unit, McGill University, Montreal General Hospital, Montreal, Quebec H3G 1A4 (Canada)

    2010-10-15

    Purpose: The objective of this work is to assess the sensitivity of Monte Carlo (MC) dose calculations to uncertainties in human tissue composition for a range of low photon energy brachytherapy sources: {sup 125}I, {sup 103}Pd, {sup 131}Cs, and an electronic brachytherapy source (EBS). The low energy photons emitted by these sources make the dosimetry sensitive to variations in tissue atomic number due to the dominance of the photoelectric effect. This work reports dose to a small mass of water in medium D{sub w,m} as opposed to dose to a small mass of medium in medium D{sub m,m}. Methods: Mean adipose, mammary gland, and breast tissues (as uniform mixture of the aforementioned tissues) are investigated as well as compositions corresponding to one standard deviation from the mean. Prostate mean compositions from three different literature sources are also investigated. Three sets of MC simulations are performed with the GEANT4 code: (1) Dose calculations for idealized TG-43-like spherical geometries using point sources. Radial dose profiles obtained in different media are compared to assess the influence of compositional uncertainties. (2) Dose calculations for four clinical prostate LDR brachytherapy permanent seed implants using {sup 125}I seeds (Model 2301, Best Medical, Springfield, VA). The effect of varying the prostate composition in the planning target volume (PTV) is investigated by comparing PTV D{sub 90} values. (3) Dose calculations for four clinical breast LDR brachytherapy permanent seed implants using {sup 103}Pd seeds (Model 2335, Best Medical). The effects of varying the adipose/gland ratio in the PTV and of varying the elemental composition of adipose and gland within one standard deviation of the assumed mean composition are investigated by comparing PTV D{sub 90} values. For (2) and (3), the influence of using the mass density from CT scans instead of unit mass density is also assessed. Results: Results from simulation (1) show that variations

  13. The American Brachytherapy Society consensus guidelines for plaque brachytherapy of uveal melanoma and retinoblastoma.

    Science.gov (United States)

    2014-01-01

    To present the American Brachytherapy Society (ABS) guidelines for plaque brachytherapy of choroidal melanoma and retinoblastoma. An international multicenter Ophthalmic Oncology Task Force (OOTF) was assembled to include 47 radiation oncologists, medical physicists, and ophthalmic oncologists from 10 countries. The ABS-OOTF produced collaborative guidelines, based on their eye cancer-specific clinical experience and knowledge of the literature. This work was reviewed and approved by the ABS Board of Directors as well as within the journal's peer-reivew process. The ABS-OOTF reached consensus that ophthalmic plaque radiation therapy is best performed in subspecialty brachytherapy centers. Quality assurance, methods of plaque construction, and dosimetry should be consistent with the 2012 joint guidelines of the American Association of Physicists in Medicine and ABS. Implantation of plaque sources should be performed by subspecialty-trained surgeons. Although there exist select restrictions related to tumor size and location, the ABS-OOTF agreed that most melanomas of the iris, ciliary body, and choroid could be treated with plaque brachytherapy. The ABS-OOTF reached consensus that tumors with gross orbital extension and blind painful eyes and those with no light perception vision are unsuitable for brachytherapy. In contrast, only select retinoblastomas are eligible for plaque brachytherapy. Prescription doses, dose rates, treatment durations, and clinical methods are described. Plaque brachytherapy is an effective eye and vision-sparing method to treat patients with intraocular tumors. Practitioners are encouraged to use ABS-OOTF guidelines to enhance their practice. Copyright © 2014 American Brachytherapy Society. All rights reserved.

  14. A novel methodology to model the cooling processes of packed horticultural produce using 3D shape models

    Science.gov (United States)

    Gruyters, Willem; Verboven, Pieter; Rogge, Seppe; Vanmaercke, Simon; Ramon, Herman; Nicolai, Bart

    2017-10-01

    Freshly harvested horticultural produce require a proper temperature management to maintain their high economic value. Towards this end, low temperature storage is of crucial importance to maintain a high product quality. Optimizing both the package design of packed produce and the different steps in the postharvest cold chain can be achieved by numerical modelling of the relevant transport phenomena. This work presents a novel methodology to accurately model both the random filling of produce in a package and the subsequent cooling process. First, a cultivar-specific database of more than 100 realistic CAD models of apple and pear fruit is built with a validated geometrical 3D shape model generator. To have an accurate representation of a realistic picking season, the model generator also takes into account the biological variability of the produce shape. Next, a discrete element model (DEM) randomly chooses surface meshed bodies from the database to simulate the gravitational filling process of produce in a box or bin, using actual mechanical properties of the fruit. A computational fluid dynamics (CFD) model is then developed with the final stacking arrangement of the produce to study the cooling efficiency of packages under several conditions and configurations. Here, a typical precooling operation is simulated to demonstrate the large differences between using actual 3D shapes of the fruit and an equivalent spheres approach that simplifies the problem drastically. From this study, it is concluded that using a simplified representation of the actual fruit shape may lead to a severe overestimation of the cooling behaviour.

  15. An accurate 3D shape context based non-rigid registration method for mouse whole-body skeleton registration

    Science.gov (United States)

    Xiao, Di; Zahra, David; Bourgeat, Pierrick; Berghofer, Paula; Acosta Tamayo, Oscar; Wimberley, Catriona; Gregoire, Marie C.; Salvado, Olivier

    2011-03-01

    Small animal image registration is challenging because of its joint structure, and posture and position difference in each acquisition without a standard scan protocol. In this paper, we face the issue of mouse whole-body skeleton registration from CT images. A novel method is developed for analyzing mouse hind-limb and fore-limb postures based on geodesic path descriptor and then registering the major skeletons and fore limb skeletons initially by thin-plate spline (TPS) transform based on the obtained geodesic paths and their enhanced correspondence fields. A target landmark correction method is proposed for improving the registration accuracy of the improved 3D shape context non-rigid registration method we previously proposed. A novel non-rigid registration framework, combining the skeleton posture analysis, geodesic path based initial alignment and 3D shape context model, is proposed for mouse whole-body skeleton registration. The performance of the proposed methods and framework was tested on 12 pairs of mouse whole-body skeletons. The experimental results demonstrated the flexibility, stability and accuracy of the proposed framework for automatic mouse whole body skeleton registration.

  16. Automatic and rapid whole-body 3D shape measurement based on multinode 3D sensing and speckle projection.

    Science.gov (United States)

    Guo, Jiping; Peng, Xiang; Li, Ameng; Liu, Xiaoli; Yu, Jiping

    2017-11-01

    Automatic and rapid whole-body 3D shape measurement has attracted extensive attention in recent years and been widely used in many fields. Rapid 3D reconstruction, automatic 3D registration, and dedicated system layout are critical factors to enable an excellent 3D measurement system. In this paper, we present an automatic and rapid whole- body 3D measurement system that is based on multinode 3D sensors using speckle projection. A rapid algorithm for searching homologous point pairs is suggested, which takes advantage of the optimized projective rectification and simplified subpixel matching techniques, leading to an improved time efficiency of 3D reconstruction. Meanwhile, a low-cost automatic system with a flexible setup and an improved calibration strategy are proposed, where system parameters of each node sensor can be simultaneously estimated with the assistance of a cubic and a planar target. Furthermore, an automatic range data registration strategy by employing two aided cameras is investigated. Experiment results show that the presented approach can realize automatic whole-body 3D shape measurement with high efficiency and accuracy.

  17. Review of MammoSite brachytherapy: Advantages, disadvantages and clinical outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Bensaleh, Saleh; Bezak, Eva; Borg, Martin (Dept. of Radiation Oncology, Royal Adelaide Hospital, Adelaide (Australia))

    2009-05-15

    Background. The MammoSite radiotherapy system is an alternative treatment option for patients with early-stage breast cancer to overcome the longer schedules associated with external beam radiation therapy. The device is placed inside the breast surgical cavity and inflated with a combination of saline and radiographic contrast to completely fill the cavity. The treatment schedule for the MammoSite monotherapy is 34 Gy delivered in 10 fractions at 1.0 cm from the balloon surface with a minimum of 6 hours between fractions on the same day. Material and methods. This review article presents the advantages, disadvantages, uncertainties and clinical outcomes associated with the MammoSite brachytherapy (MSB). Results. Potential advantages of MSB are: high localised dose with rapid falloff for normal tissue sparing, minimum delay between surgery and RT, catheter moves with breast, improved local control, no exposure to staff, likely side-effects reduction and potential cost/time saving (e.g. for country patients). The optimal cosmetic results depend on the balloon-to-skin distance. Good-to-excellent cosmetic results are achieved for patients with balloon-skin spacing of =7 mm. There have been very few published data regarding the long term tumour control and cosmesis associated with the MSB. The available data on the local control achieved with the MSB were comparable with other accelerated partial breast irradiation techniques. The contrast medium inside the balloon causes dose reduction at the prescription point. Current brachytherapy treatment planning systems (BTPS) do not take into account the increased photon attenuation due to high Z of contrast. Some BTPS predicted up to 10% higher dose near the balloon surface compared with Monte Carlo calculations using various contrast concentrations (5-25%). Conclusion. Initial clinical results have shown that the MammoSite device could be used as a sole radiation treatment for selected patients with early stage breast cancer

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

    Science.gov (United States)

    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

  19. Late coronary occlusion after intracoronary brachytherapy

    NARCIS (Netherlands)

    M.A. Costa (Marco); M. Sabaté (Manel); I.P. Kay (Ian Patrick); P. Cervinka; J.M.R. Ligthart (Jürgen); P. Serrano (Pedro); V.L.M.A. Coen (Veronique); P.W.J.C. Serruys (Patrick); P.C. Levendag (Peter); W.J. van der Giessen (Wim)

    1999-01-01

    textabstractBACKGROUND: Intracoronary brachytherapy appears to be a promising technology to prevent restenosis. Presently, limited data are available regarding the late safety of this therapeutic modality. The aim of the study was to determine the incidence of late (>1 month)

  20. Concomitant chemoradiotherapy with high dose rate brachytherapy ...

    African Journals Online (AJOL)

    Purpose: This study aims to report the incidence of treatment-induced acute toxicities, local control and survival of patients with cervix cancer treated by external beam radiotherapy (EBR) and high-dose-rate (HDR) brachytherapy concomitant with weekly Cisplatin chemotherapy. Methods: Forty patients with FIGO Stages IB2 ...

  1. MO-D-BRD-00: Electronic Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    Electronic brachytherapy (eBT) has seen an insurgence of manufacturers entering the US market for use in radiation therapy. In addition to the established interstitial, intraluminary, and intracavitary applications of eBT, many centers are now using eBT to treat skin lesions. It is important for medical physicists working with electronic brachytherapy sources to understand the basic physics principles of the sources themselves as well as the variety of applications for which they are being used. The calibration of the sources is different from vendor to vendor and the traceability of calibrations has evolved as new sources came to market. In 2014, a new air-kerma based standard was introduced by the National Institute of Standards and Technology (NIST) to measure the output of an eBT source. Eventually commercial treatment planning systems should accommodate this new standard and provide NIST traceability to the end user. The calibration and commissioning of an eBT system is unique to its application and typically entails a list of procedural recommendations by the manufacturer. Commissioning measurements are performed using a variety of methods, some of which are modifications of existing AAPM Task Group protocols. A medical physicist should be familiar with the different AAPM Task Group recommendations for applicability to eBT and how to properly adapt them to their needs. In addition to the physical characteristics of an eBT source, the photon energy is substantially lower than from HDR Ir-192 sources. Consequently, tissue-specific dosimetry and radiobiological considerations are necessary when comparing these brachytherapy modalities and when making clinical decisions as a radiation therapy team. In this session, the physical characteristics and calibration methodologies of eBt sources will be presented as well as radiobiology considerations and other important clinical considerations. Learning Objectives: To understand the basic principles of electronic

  2. Prostate brachytherapy in Ghana: our initial experience.

    Science.gov (United States)

    Mensah, James Edward; Yarney, Joel; Vanderpuye, Verna; Akpakli, Evans; Tagoe, Samuel; Sasu, Evans

    2016-10-01

    This study presents the experience of a brachytherapy team in Ghana with a focus on technology transfer and outcome. The team was initially proctored by experienced physicians from Europe and South Africa. A total of 90 consecutive patients underwent either brachytherapy alone or brachytherapy in combination with external beam radiotherapy for prostate carcinoma between July 2008 and February 2014 at Korle Bu Teaching Hospital, Accra, Ghana. Patients were classified as low-risk, intermediate, and high-risk according to the National Comprehensive Cancer Network (NCCN) criteria. All low-risk and some intermediate risk group patients were treated with seed implantation alone. Some intermediate and all high-risk group patients received brachytherapy combined with external beam radiotherapy. The median patient age was 64.0 years (range 46-78 years). The median follow-up was 58 months (range 18-74 months). Twelve patients experienced biochemical failure including one patient who had evidence of metastatic disease and died of prostate cancer. Freedom from biochemical failure rates for low, intermediate, and high-risk cases were 95.4%, 90.9%, and 70.8%, respectively. Clinical parameters predictive of biochemical outcome included: clinical stage, Gleason score, and risk group. Pre-treatment prostate specific antigen (PSA) was not a statistically significant predictor of biochemical failure. Sixty-nine patients (76.6%) experienced grade 1 urinary symptoms in the form of frequency, urgency, and poor stream. These symptoms were mostly self-limiting. Four patients needed catheterization for urinary retention (grade 2). One patient developed a recto urethral fistula (grade 3) following banding for hemorrhoids. Our results compare favorably with those reported by other institutions with more extensive experience. We believe therefore that, interstitial permanent brachytherapy can be safely and effectively performed in a resource challenged environment if adequate training

  3. Prostate brachytherapy in Ghana: our initial experience

    Directory of Open Access Journals (Sweden)

    James Edward Mensah

    2016-10-01

    Full Text Available Purpose: This study presents the experience of a brachytherapy team in Ghana with a focus on technology transfer and outcome. The team was initially proctored by experienced physicians from Europe and South Africa. Material and methods : A total of 90 consecutive patients underwent either brachytherapy alone or brachytherapy in combination with external beam radiotherapy for prostate carcinoma between July 2008 and February 2014 at Korle Bu Teaching Hospital, Accra, Ghana. Patients were classified as low-risk, intermediate, and high-risk according to the National Comprehensive Cancer Network (NCCN criteria. All low-risk and some intermediate risk group patients were treated with seed implantation alone. Some intermediate and all high-risk group patients received brachytherapy combined with external beam radiotherapy. Results: The median patient age was 64.0 years (range 46-78 years. The median follow-up was 58 months (range 18-74 months. Twelve patients experienced biochemical failure including one patient who had evidence of metastatic disease and died of prostate cancer. Freedom from biochemical failure rates for low, intermediate, and high-risk cases were 95.4%, 90.9%, and 70.8%, respectively. Clinical parameters predictive of biochemical outcome included: clinical stage, Gleason score, and risk group. Pre-treatment prostate specific antigen (PSA was not a statistically significant predictor of biochemical failure. Sixty-nine patients (76.6% experienced grade 1 urinary symptoms in the form of frequency, urgency, and poor stream. These symptoms were mostly self-limiting. Four patients needed catheterization for urinary retention (grade 2. One patient developed a recto urethral fistula (grade 3 following banding for hemorrhoids. Conclusions : Our results compare favorably with those reported by other institutions with more extensive experience. We believe therefore that, interstitial permanent brachytherapy can be safely and effectively

  4. Dose volume uniformity index: a simple tool for treatment plan evaluation in brachytherapy

    Directory of Open Access Journals (Sweden)

    Ramachandran Prabhakar

    2010-07-01

    Full Text Available Purpose: In radiotherapy treatment planning, dose homogeneity inside the target volume plays a significant role in the final treatment outcome. Especially in brachytherapy where there is a steep dose gradient in the dose distribution inside the target volume, comparing the plans based on the dose homogeneity helps in assessing the high dose volume inside the final treatment plan. In brachytherapy, the dose inhomogeneity inside the target volume depends on many factors such as the type of sources, placement of these radioactive sources, distance between the applicators/implanttubes, dwell time of the source, etc. In this study, a simple index, the dose volume uniformity index (DVUI, has been proposed to study the dose homogeneity inside the target volume. This index gives the total dose volume inhomogeneity inside a given prescription isoline.Material and methods: To demonstrate the proposed DVUI in this study, a single plane implant (breast: 6 catheters, a double plane implant (breast: 9 catheters and a tongue implant (5 catheters were selected. The catheters were reconstructed from the CT image datasets in the Plato treatment planning system. The doses for the single, double and tongue implants were prescribed to the reference dose rate as per the Paris technique. DVUI was computed from the cumulative dose volume histogram.Results: For a volume receiving a uniform dose inside the prescription isoline, the DVUI is 1. Any value of DVUI > 1 shows the presence of a relatively high dose volume inside the prescription isoline. In addition to the concept of DVUI, a simple conformality index, the dose volume conformality index (DVCI, has also been proposed in this study based on the DVUI.Conclusion: The DVUI and the proposed DVCI in this study provide an easy way of comparing the rival plans in brachytherapy.

  5. 3D shape of asteroid (6) Hebe from VLT/SPHERE imaging: Implications for the origin of ordinary H chondrites

    Science.gov (United States)

    Marsset, M.; Carry, B.; Dumas, C.; Hanuš, J.; Viikinkoski, M.; Vernazza, P.; Müller, T. G.; Delbo, M.; Jehin, E.; Gillon, M.; Grice, J.; Yang, B.; Fusco, T.; Berthier, J.; Sonnett, S.; Kugel, F.; Caron, J.; Behrend, R.

    2017-08-01

    Context. The high-angular-resolution capability of the new-generation ground-based adaptive-optics camera SPHERE at ESO VLT allows us to assess, for the very first time, the cratering record of medium-sized (D 100-200 km) asteroids from the ground, opening the prospect of a new era of investigation of the asteroid belt's collisional history. Aims: We investigate here the collisional history of asteroid (6) Hebe and challenge the idea that Hebe may be the parent body of ordinary H chondrites, the most common type of meteorites found on Earth ( 34% of the falls). Methods: We observed Hebe with SPHERE as part of the science verification of the instrument. Combined with earlier adaptive-optics images and optical light curves, we model the spin and three-dimensional (3D) shape of Hebe and check the consistency of the derived model against available stellar occultations and thermal measurements. Results: Our 3D shape model fits the images with sub-pixel residuals and the light curves to 0.02 mag. The rotation period (7.274 47 h), spin (ECJ2000 λ, β of 343°, +47°), and volume-equivalent diameter (193 ± 6 km) are consistent with previous determinations and thermophysical modeling. Hebe's inferred density is 3.48 ± 0.64 g cm-3, in agreement with an intact interior based on its H-chondrite composition. Using the 3D shape model to derive the volume of the largest depression (likely impact crater), it appears that the latter is significantly smaller than the total volume of close-by S-type H-chondrite-like asteroid families. Conclusions: Our results imply that (6) Hebe is not the most likely source of H chondrites. Over the coming years, our team will collect similar high-precision shape measurements with VLT/SPHERE for 40 asteroids covering the main compositional classes, thus providing an unprecedented dataset to investigate the origin and collisional evolution of the asteroid belt. Based on observations made with ESO Telescopes at the La Silla Paranal Observatory

  6. Radiation-induced circumscribed superficial morphea after brachytherapy for endometrial adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Apoorva Trivedi, BS

    2017-12-01

    Full Text Available Radiation-induced morphea (RIM is a rare and underrecognized complication of radiation therapy that most commonly occurs in women after treatment for breast cancer. Although not fully understood, RIM is hypothesized to arise from an increase in cytokines that stimulate collagen production and extracellular matrix formation. Most documented cases of RIM occur 1 year after radiation therapy and are localized to areas that were treated for breast cancer. We report on a case of a female patient with stage IB endometrial adenocarcinoma who was treated with 24 Gray of adjuvant brachytherapy. The patient developed a diffuse morpheaform, pruritic eruption only at distant sites from the brachytherapy treatment field. Although treatment for RIM is generally unsatisfactory, our patient experienced improvement in the pruritus and a regression of the lesions while applying topical 0.1% tacrolimus ointment and 0.1% triamcinolone creme. An early diagnosis of RIM can prevent extensive workup, guide treatment, and improve quality of life for patients. Keywords: radiation-induced morphea, postirradiation morphea

  7. SU-F-BRA-02: Electromagnetic Tracking in Brachytherapy as An Advanced Modality for Treatment Quality Assurance

    Energy Technology Data Exchange (ETDEWEB)

    Kellermeier, M; Herbolzheimer, J; Kreppner, S; Lotter, M; Strnad, V [University Clinic Erlangen, Department of Radiation Oncology, Erlangen, DE (Germany); Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, DE (Germany); Bert, C [University Clinic Erlangen, Department of Radiation Oncology, Erlangen, DE (Germany); Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, DE (Germany); GSI Helmholtz Centre for Heavy Ion Research, Darmstadt, DE (Germany)

    2015-06-15

    Purpose: To present the use of Electromagnetic Tracking (EMT) for quality assurance in brachytherapy by means of phantom studies and to assess the clinical applicability of EMT during HDR breast brachytherapy. Methods: An EMT system was investigated to examine its suitability for clinical applications in brachytherapy. A field generator served as electromagnetic field emitter. Sensors (magnetic sensitive only), connected to a control unit, were used and their respective position and orientation inside a pre-defined measurement volume (500 mm cube length) determined. Up to three 6DoF sensors were placed on the phantom’s surface to obtain additional reference coordinates used to derive relative measured positions of a smaller 5DoF sensor inserted in the 6F catheters of the implant. The catheters were successively measured by manual displacement of the sensor at ∼40 mm/s. The measured catheter tracks, acquired multiple times at various locations (CT and treatment room), were smoothed, divided into intervals (2.5 mm dwell step size), registered (rigid Iterative Closest Point transformation) and compared against the known phantom geometry. Results: The reference coordinates were used to exclude the influence of external (e.g., respiratory-induced) motion. Precision tests in a clinical setting showed variances below 1 mm (translational) and 1° (rotational), respectively. Our method for catheter reconstruction preserved the length of the tracked catheter (within 1 mm). The measured tracking accuracy was 1±0.3 mm (maximum: 2 mm). The results are less accurate in environments potentially interfering with the magnetic field, e.g., in the vicinity of ferromagnetic table components. Conclusion: Our EMT system is able to perform reproducible and accurate catheter tracking and reconstruction. Currently, measurements of the implant geometry in HDR breast treatments are initiated. Online implant monitoring by means of EM tracking may be a first step towards advanced

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

    Science.gov (United States)

    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 for...

  9. 10 CFR 35.67 - Requirements for possession of sealed sources and brachytherapy sources.

    Science.gov (United States)

    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 physical...

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

    Science.gov (United States)

    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

  11. The difference of scoring dose to water or tissues in Monte Carlo dose calculations for low energy brachytherapy photon sources.

    Science.gov (United States)

    Landry, Guillaume; Reniers, Brigitte; Pignol, Jean-Philippe; Beaulieu, Luc; Verhaegen, Frank

    2011-03-01

    The goal of this work is to compare D(m,m) (radiation transported in medium; dose scored in medium) and D(w,m) (radiation transported in medium; dose scored in water) obtained from Monte Carlo (MC) simulations for a subset of human tissues of interest in low energy photon brachytherapy. Using low dose rate seeds and an electronic brachytherapy source (EBS), the authors quantify the large cavity theory conversion factors required. The authors also assess whether ap plying large cavity theory utilizing the sources' initial photon spectra and average photon energy induces errors related to spatial spectral variations. First, ideal spherical geometries were investigated, followed by clinical brachytherapy LDR seed implants for breast and prostate cancer patients. Two types of dose calculations are performed with the GEANT4 MC code. (1) For several human tissues, dose profiles are obtained in spherical geometries centered on four types of low energy brachytherapy sources: 125I, 103Pd, and 131Cs seeds, as well as an EBS operating at 50 kV. Ratios of D(w,m) over D(m,m) are evaluated in the 0-6 cm range. In addition to mean tissue composition, compositions corresponding to one standard deviation from the mean are also studied. (2) Four clinical breast (using 103Pd) and prostate (using 125I) brachytherapy seed implants are considered. MC dose calculations are performed based on postimplant CT scans using prostate and breast tissue compositions. PTV D90 values are compared for D(w,m) and D(m,m). (1) Differences (D(w,m)/D(m,m)-1) of -3% to 70% are observed for the investigated tissues. For a given tissue, D(w,m)/D(m,m) is similar for all sources within 4% and does not vary more than 2% with distance due to very moderate spectral shifts. Variations of tissue composition about the assumed mean composition influence the conversion factors up to 38%. (2) The ratio of D90(w,m) over D90(m,m) for clinical implants matches D(w,m)/D(m,m) at 1 cm from the single point sources, Given

  12. In vivo dose verification method in catheter based high dose rate brachytherapy.

    Science.gov (United States)

    Jaselskė, Evelina; Adlienė, Diana; Rudžianskas, Viktoras; Urbonavičius, Benas Gabrielis; Inčiūra, Arturas

    2017-12-01

    In vivo dosimetry is a powerful tool for dose verification in radiotherapy. Its application in high dose rate (HDR) brachytherapy is usually limited to the estimation of gross errors, due to inability of the dosimetry system/ method to record non-uniform dose distribution in steep dose gradient fields close to the radioactive source. In vivo dose verification in interstitial catheter based HDR brachytherapy is crucial since the treatment is performed inserting radioactive source at the certain positions within the catheters that are pre-implanted into the tumour. We propose in vivo dose verification method for this type of brachytherapy treatment which is based on the comparison between experimentally measured and theoretical dose values calculated at well-defined locations corresponding dosemeter positions in the catheter. Dose measurements were performed using TLD 100-H rods (6 mm long, 1 mm diameter) inserted in a certain sequences into additionally pre-implanted dosimetry catheter. The adjustment of dosemeter positioning in the catheter was performed using reconstructed CT scans of patient with pre-implanted catheters. Doses to three Head&Neck and one Breast cancer patient have been measured during several randomly selected treatment fractions. It was found that the average experimental dose error varied from 4.02% to 12.93% during independent in vivo dosimetry control measurements for selected Head&Neck cancer patients and from 7.17% to 8.63% - for Breast cancer patient. Average experimental dose error was below the AAPM recommended margin of 20% and did not exceed the measurement uncertainty of 17.87% estimated for this type of dosemeters. Tendency of slightly increasing average dose error was observed in every following treatment fraction of the same patient. It was linked to the changes of theoretically estimated dosemeter positions due to the possible patient's organ movement between different treatment fractions, since catheter reconstruction was

  13. Development of a brachytherapy audit checklist tool.

    Science.gov (United States)

    Prisciandaro, Joann; Hadley, Scott; Jolly, Shruti; Lee, Choonik; Roberson, Peter; Roberts, Donald; Ritter, Timothy

    2015-01-01

    To develop a brachytherapy audit checklist that could be used to prepare for Nuclear Regulatory Commission or agreement state inspections, to aid in readiness for a practice accreditation visit, or to be used as an annual internal audit tool. Six board-certified medical physicists and one radiation oncologist conducted a thorough review of brachytherapy-related literature and practice guidelines published by professional organizations and federal regulations. The team members worked at two facilities that are part of a large, academic health care center. Checklist items were given a score based on their judged importance. Four clinical sites performed an audit of their program using the checklist. The sites were asked to score each item based on a defined severity scale for their noncompliance, and final audit scores were tallied by summing the products of importance score and severity score for each item. The final audit checklist, which is available online, contains 83 items. The audit scores from the beta sites ranged from 17 to 71 (out of 690) and identified a total of 7-16 noncompliance items. The total time to conduct the audit ranged from 1.5 to 5 hours. A comprehensive audit checklist was developed which can be implemented by any facility that wishes to perform a program audit in support of their own brachytherapy program. The checklist is designed to allow users to identify areas of noncompliance and to prioritize how these items are addressed to minimize deviations from nationally-recognized standards. Copyright © 2015 American Brachytherapy Society. All rights reserved.

  14. Design and optimization of a brachytherapy robot

    Science.gov (United States)

    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.

  15. Adaptation of the CVT algorithm for catheter optimization in high dose rate brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Poulin, Eric; Fekete, Charles-Antoine Collins; Beaulieu, Luc [Département de Physique, de Génie Physique et d’Optique et Centre de recherche sur le cancer de l’Université Laval, Université Laval, Québec, Québec G1V 0A6, Canada and Département de Radio-Oncologie et Axe oncologie du Centre de Recherche du CHU de Québec, CHU de Québec, 11 Côte du Palais, Québec, Québec G1R 2J6 (Canada); Létourneau, Mélanie [Département de Radio-Oncologie, CHU de Québec, 11 Côte du Palais, Québec, Québec G1R 2J6 (Canada); Fenster, Aaron [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (United Kingdom); Pouliot, Jean [Department of Radiation Oncology, University of California San Francisco, Helen Diller Family Comprehensive Cancer Center, 1600 Divisadero Street, San Francisco, California 94143-1708 (United States)

    2013-11-15

    Purpose: An innovative, simple, and fast method to optimize the number and position of catheters is presented for prostate and breast high dose rate (HDR) brachytherapy, both for arbitrary templates or template-free implants (such as robotic templates).Methods: Eight clinical cases were chosen randomly from a bank of patients, previously treated in our clinic to test our method. The 2D Centroidal Voronoi Tessellations (CVT) algorithm was adapted to distribute catheters uniformly in space, within the maximum external contour of the planning target volume. The catheters optimization procedure includes the inverse planning simulated annealing algorithm (IPSA). Complete treatment plans can then be generated from the algorithm for different number of catheters. The best plan is chosen from different dosimetry criteria and will automatically provide the number of catheters and their positions. After the CVT algorithm parameters were optimized for speed and dosimetric results, it was validated against prostate clinical cases, using clinically relevant dose parameters. The robustness to implantation error was also evaluated. Finally, the efficiency of the method was tested in breast interstitial HDR brachytherapy cases.Results: The effect of the number and locations of the catheters on prostate cancer patients was studied. Treatment plans with a better or equivalent dose distributions could be obtained with fewer catheters. A better or equal prostate V100 was obtained down to 12 catheters. Plans with nine or less catheters would not be clinically acceptable in terms of prostate V100 and D90. Implantation errors up to 3 mm were acceptable since no statistical difference was found when compared to 0 mm error (p > 0.05). No significant difference in dosimetric indices was observed for the different combination of parameters within the CVT algorithm. A linear relation was found between the number of random points and the optimization time of the CVT algorithm. Because the

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

    Directory of Open Access Journals (Sweden)

    Banerjee R

    2014-05-01

    Full Text Available Robyn Banerjee,1 Mitchell Kamrava21Department of Radiation Oncology, Tom Baker Cancer Centre, Calgary, Alberta, Canada; 2Department of Radiation Oncology, University of California Los Angeles, Los Angeles, CA, USAAbstract: 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.Keywords: cervical cancer, brachytherapy, image-guided brachytherapy

  17. Improving the efficiency of image guided brachytherapy in cervical cancer

    Directory of Open Access Journals (Sweden)

    Sophie Otter

    2016-12-01

    Full Text Available Brachytherapy is an essential component of the treatment of locally advanced cervical cancers. It enables the dose to the tumor to be boosted whilst allowing relative sparing of the normal tissues. Traditionally, cervical brachytherapy was prescribed to point A but since the GEC-ESTRO guidelines were published in 2005, there has been a move towards prescribing the dose to a 3D volume. Image guided brachytherapy has been shown to reduce local recurrence, and improve survival and is optimally predicated on magnetic resonance imaging. Radiological studies, patient workflow, operative parameters, and intensive therapy planning can represent a challenge to clinical resources. This article explores the ways, in which 3D conformal brachytherapy can be implemented and draws findings from recent literature and a well-developed hospital practice in order to suggest ways to improve the efficiency and efficacy of a brachytherapy service. Finally, we discuss relatively underexploited translational research opportunities.

  18. Breast conserving treatment of locally advanced carcinoma T2 and T3 after neoadjuvant chemotherapy followed by quadrantectomy and high dose-rate brachytherapy, as a boost, complementary teletherapy and adjuvant chemotherapy; Tratamento conservador dos carcinomas de mama localmente avancados T2 e T3, apos quimioterapia neoadjuvante, com quadrantectomia e braquiterapia de alta taxa de dose como reforco de dose, teleterapia complementar e quimioterapia adjuvante

    Energy Technology Data Exchange (ETDEWEB)

    Fristachi, Carlos Elias [Instituto do Cancer Dr. Arnaldo Vieira de Carvalho (ICAVC), Sao Paulo, SP (Brazil). Servico de Onco-Ginecologia e Mastologia]. E-mail: cefristachi@uol.com.br; Miziara Filho, Miguel Abrao; Soares, Celia Regina; Fogaroli, Ricardo Cesar; Pelosi, Edilson Lopes; Martins, Homero Lavieri Martins [Instituto do Cancer Dr. Arnaldo Vieira de Carvalho (ICAVC), Sao Paulo, SP (Brazil). Servico de Radioterapia; Baracat, Fausto Farah [Hospital do Servidor Publico Estadual de Sao Paulo (HSPE), SP (Brazil). Servico de Ginecologia e Mastologia; Piato, Sebastiao [Irmandade da Santa Casa de Misericordia de Sao Paulo, SP (Brazil). Dept. de Obstetricia e Ginecologia (DOGI)

    2005-07-01

    Objective: to assess the treatment of breast cancer T2 and T3(T > = 4 cm), through neoadjuvant chemotherapy, quadrantectomy and high-dose-rate (HDR) brachytherapy as a boost, complementary radiotherapy and adjuvant chemotherapy, considering its method problems, its esthetics results, the aspect of local control, overall survival, and disease-free survival. Patients and method: this clinical prospective descriptive study was based on the evaluation of 26 patients ranging from 30 to 70 years old, with infiltrating ductal carcinoma, clinical stage IIB and IIIA, responsive to the neoadjuvant chemotherapy. Early and late radiotherapy complications were evaluated according to the criteria established by the RTOG/EORTC (Radiotherapy and Oncology Group /European Organization for Research and Treatment of Cancer) groups. Esthetics evaluation was done in accordance with the criteria set by a plastic surgeon. Local control was evaluated by clinical method, mammography and ultrasonography. Overall survival (OS) and the disease-free survival (DFS) were assessed according to Kaplan-Meier methodology. All the patients were treated at the Dr. Arnaldo Vieira de Carvalho Cancer Institute, from June/1995 to November/2001, and evaluated in March, 2002, with median follow-up of 28.7 months. Results: early complications were observed in 8 patients (30.6%). Two patients were classified as G3 and G4 (RTOG/EORTC). Six patients had late complications and three of them (11.5%) were classified as G3 and G4. One patient (3.8%) had local recurrence, 64 months after having local treatment. Esthetics results were considered good or regular in 16 patients (60.5%) out of 24 patients who were examined. Overall survival and disease-free survival in 24, 36 and 60 months were 100%, 92.3% and 83.1% respectively. Conclusion: early and late radiotherapy complications were considerate high when compared to literature, but esthetic results were considered acceptable. RL, OS and DFS were comparable to other

  19. Conformal treatment planning for interstitial brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kovacs, G. [Kiel Univ. (Germany). Klinik fuer Strahlentherapie (Radioonkologie); Hebbinghaus, D. [Kiel Univ. (Germany). Klinik fuer Strahlentherapie (Radioonkologie); Dennert, P. [Kiel Univ. (Germany). Klinik fuer Strahlentherapie (Radioonkologie); Kohr, P. [Kiel Univ. (Germany). Klinik fuer Strahlentherapie (Radioonkologie); Wilhelm, R. [Kiel Univ. (Germany). Klinik fuer Strahlentherapie (Radioonkologie); Kimmig, B. [Kiel Univ. (Germany). Klinik fuer Strahlentherapie (Radioonkologie)

    1996-09-01

    Quality of a brachytherapy application depends on the choice of the target volume, on the dose distribution homogeneity and radiation injury on critical tissue, which should be postulated by advanced brachytherapy treatment planning systems. Basic imaging method for conformal treatment planning is the cross-sectional imaging. The clinical applicatibility of a new type 3D planning system using CT and/or MRT-simulation or US-simulation for planning purposes was studied. The planning system developed at Kiel University differs from usual brachytherapy planning systems because of the obligatory use of cross-sectional imaging as basic imaging method for reconstruction of structures of interest. Dose distribution and normal anatomy can be visualized on each CT/MRT/US slice as well as coronal, sagittal, axial and free chosen reconstructions (3D), as well as dose-volume histogram curves and special colour-coded visualization of dose homogeneity in the target can be analyzed. Because of the experience in the clinical routine, as well as on the base of 30 simultaneous planning procedures on both 2D (semi-3D) and 3D planning systems we observed similar time consumption. Advantages of 3D planning were the better interpretation of target delineation, delineation of critical structures as well as dose distribution, causing more accurate volume optimisation of dose distribution. Conformal brachytherapy treatment planning for interstitial brachytherapy means significant advantages for the clinical routine compared to 2D or semi-3D methods. (orig.) [Deutsch] Die Qualitaet einer Brachytherapieapplikation ist abhaengig von der Zielvolumenwahl, der homogenen Dosisverteilung und der Schonung kritischer Organe. Diese Voraussetzungen koennen am besten mit Hilfe eines 3D-Planungssystem erfuellt werden. Als Planungsvorlage fuer die Konformationstherapieplanung sind am besten Schnittbilder (CT, MRT, US) geeignet. Es wurde die Anwendbarkeit eines auf CT- (oder MRT-)Simulation oder geeignete

  20. 3D Shape-Encoded Particle Filter for Object Tracking and Its Application to Human Body Tracking

    Directory of Open Access Journals (Sweden)

    R. Chellappa

    2008-03-01

    Full Text Available We present a nonlinear state estimation approach using particle filters, for tracking objects whose approximate 3D shapes are known. The unnormalized conditional density for the solution to the nonlinear filtering problem leads to the Zakai equation, and is realized by the weights of the particles. The weight of a particle represents its geometric and temporal fit, which is computed bottom-up from the raw image using a shape-encoded filter. The main contribution of the paper is the design of smoothing filters for feature extraction combined with the adoption of unnormalized conditional density weights. The “shape filter” has the overall form of the predicted 2D projection of the 3D model, while the cross-section of the filter is designed to collect the gradient responses along the shape. The 3D-model-based representation is designed to emphasize the changes in 2D object shape due to motion, while de-emphasizing the variations due to lighting and other imaging conditions. We have found that the set of sparse measurements using a relatively small number of particles is able to approximate the high-dimensional state distribution very effectively. As a measures to stabilize the tracking, the amount of random diffusion is effectively adjusted using a Kalman updating of the covariance matrix. For a complex problem of human body tracking, we have successfully employed constraints derived from joint angles and walking motion.

  1. 3D Shape-Encoded Particle Filter for Object Tracking and Its Application to Human Body Tracking

    Directory of Open Access Journals (Sweden)

    Chellappa R

    2008-01-01

    Full Text Available Abstract We present a nonlinear state estimation approach using particle filters, for tracking objects whose approximate 3D shapes are known. The unnormalized conditional density for the solution to the nonlinear filtering problem leads to the Zakai equation, and is realized by the weights of the particles. The weight of a particle represents its geometric and temporal fit, which is computed bottom-up from the raw image using a shape-encoded filter. The main contribution of the paper is the design of smoothing filters for feature extraction combined with the adoption of unnormalized conditional density weights. The "shape filter" has the overall form of the predicted 2D projection of the 3D model, while the cross-section of the filter is designed to collect the gradient responses along the shape. The 3D-model-based representation is designed to emphasize the changes in 2D object shape due to motion, while de-emphasizing the variations due to lighting and other imaging conditions. We have found that the set of sparse measurements using a relatively small number of particles is able to approximate the high-dimensional state distribution very effectively. As a measures to stabilize the tracking, the amount of random diffusion is effectively adjusted using a Kalman updating of the covariance matrix. For a complex problem of human body tracking, we have successfully employed constraints derived from joint angles and walking motion.

  2. Shape optimization of active and passive drag-reducing devices on a D-shaped bluff body

    CERN Document Server

    Semaan, Richard

    2016-01-01

    Shape optimization of an active and a passive drag-reducing device on a two-dimensional D-shaped bluff body is performed. The two devices are: Coanda actuator, and randomly-shaped trailing-edge flap. The optimization sequence is performed by coupling the genetic algorithm software DAKOTA to the mesh generator Pointwise and to the CFD solver OpenFOAM. For the the active device the cost functional is the power ratio, whereas for the passive device it is the drag coefficient. The optimization leads to total power savings of $\\approx 70\\%$ for the optimal Coanda actuator, and a 40\\% drag reduction for the optimal flap. This reduction is mainly achieved through streamlining the base flow and suppressing the vortex shedding. The addition of either an active or a passive device creates two additional smaller recirculation regions in the base cavity that shifts the larger recirculation region away from the body and increases the base pressure. The results are validated against more refined URANS simulations for selec...

  3. Micro Fourier Transform Profilometry (μFTP): 3D shape measurement at 10,000 frames per second

    Science.gov (United States)

    Zuo, Chao; Tao, Tianyang; Feng, Shijie; Huang, Lei; Asundi, Anand; Chen, Qian

    2018-03-01

    Fringe projection profilometry is a well-established technique for optical 3D shape measurement. However, in many applications, it is desirable to make 3D measurements at very high speed, especially with fast moving or shape changing objects. In this work, we demonstrate a new 3D dynamic imaging technique, Micro Fourier Transform Profilometry (μFTP), which can realize an acquisition rate up to 10,000 3D frame per second (fps). The high measurement speed is achieved by the number of patterns reduction as well as high-speed fringe projection hardware. In order to capture 3D information in such a short period of time, we focus on the improvement of the phase recovery, phase unwrapping, and error compensation algorithms, allowing to reconstruct an accurate, unambiguous, and distortion-free 3D point cloud with every two projected patterns. We also develop a high-frame-rate fringe projection hardware by pairing a high-speed camera and a DLP projector, enabling binary pattern switching and precisely synchronized image capture at a frame rate up to 20,000 fps. Based on this system, we demonstrate high-quality textured 3D imaging of 4 transient scenes: vibrating cantilevers, rotating fan blades, flying bullet, and bursting balloon, which were previously difficult or even unable to be captured with conventional approaches.

  4. SU-GG-T-49: Real Time Dose Verification for Novel Shielded Balloon Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Govindarajan, Nandakarthik; Nazaryan, Vahagn; Gueye, Paul; Keppel, Cynthia

    2010-06-01

    Purpose: The validation of a novel approach for reducing skindoses to an acceptable level during Accelerated Partial Breast Irradiation (APBI) when the balloon-to-skin distance is inadequate (less than 7 mm) is reported. The study uses a real time dose verification method for a metallic shielded balloon applicator using scintillation fiber technology. Method and Materials: Partial shielding of the radiationdose to the skin using iron or other ferrous powder could enable the extension of APBI to some patients. With small external and pre-determined magnetic fields (breast and torso phantoms of differing sizes. The dose on the external surface of the skin was measured from a 6.1 Ci {sup 192}Ir of a GammaMed 12i afterloader unit, with a MOSFET,ion chamber and scintillating fiber array detectors. Results: Realistic Monte Carlo simulation studies for the amount and distribution of the required shielding material were compared to dedicated phantom data. A decrease of the skindose was measured to an acceptable level (~350-450 cGy) during standard breast Brachytherapy treatments with relatively weak magnetic fields. Additional measurements provided negligible corrections (< few %) on the saline water density from the suspended ironpowder.Conclusion: This project opens the possibility to increasing the survival expectancy and minimizing negative side effects during brachytherapy treatments, as well as improving cosmetic outcome for all APBI patients. The proposed method may also be used in other procedures for brain, heart, rectal, or vaginal cancers.

  5. Experimental and computational development of a natural breast phantom for dosimetry studies

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, Luciana B.; Campos, Tarcisio P.R., E-mail: lucibn19@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2013-07-01

    This paper describes the experimental and computational development of a natural breast phantom, anthropomorphic and anthropometric for studies in dosimetry of brachytherapy and teletherapy of breast. The natural breast phantom developed corresponding to fibroadipose breasts of women aged 30 to 50 years, presenting radiographically medium density. The experimental breast phantom was constituted of three tissue-equivalents (TE's): glandular TE, adipose TE and skin TE. These TE's were developed according to chemical composition of human breast and present radiological response to exposure. Completed the construction of experimental breast phantom this was mounted on a thorax phantom previously developed by the research group NRI/UFMG. Then the computational breast phantom was constructed by performing a computed tomography (CT) by axial slices of the chest phantom. Through the images generated by CT a computational model of voxels of the thorax phantom was developed by SISCODES computational program, being the computational breast phantom represented by the same TE's of the experimental breast phantom. The images generated by CT allowed evaluating the radiological equivalence of the tissues. The breast phantom is being used in studies of experimental dosimetry both in brachytherapy as in teletherapy of breast. Dosimetry studies by MCNP-5 code using the computational model of the phantom breast are in progress. (author)

  6. Simulated Optimization of Brachytherapy for the Treatment of Breast Cancer

    Science.gov (United States)

    2014-03-01

    Q4 Courses/Study Cancer biology Radiation biology Radiotherapy Physics Medical Imaging Clinical Skills Delivery Methods Treatment Planning...generate histories until a sigma value of ɘ.5 was achieved. The average number of histories it took to achieve this was on the order of 10^9...Actual Dose was calculated using the formula D! = A ⋅ t ⋅ f ⋅ D!!"where D! is the actual dose in eV/(g* histories ), Ais activity in disintegrations/sec, t

  7. Morphea as a consequence of accelerated partial breast irradiation.

    Science.gov (United States)

    Wernicke, A Gabriella; Goltser, Yevgeniya; Trichter, Samuel; Sabbas, Albert; Gaan, Jalong; Swistel, Alexander J; Magro, Cynthia M

    2011-03-01

    Morphea is a localized form of scleroderma usually unaccompanied by the typical systemic stigmata that characterize progressive systemic scleroderma. It rarely manifests at the site of whole breast external-beam radiation therapy. We present an unusual case of radiation-induced morphea (RIM) that occurred after accelerated partial breast irradiation (APBI) using intracavitary Contura brachytherapy. A 65-year-old white woman was treated for stage IIA invasive ductal carcinoma of the left breast with APBI to a dose of 34 Gy in 3.4-Gy fractions twice daily over the course 5 days with intracavitary brachytherapy. At 1.5 years after completion of APBI, the patient developed an area of tenderness, erythema, and induration at the site of irradiation. A skin biopsy was consistent with morphea. To our knowledge, this is the first case of RIM confined to the area of APBI.

  8. In vivo measurements for high dose rate brachytherapy with optically stimulated luminescent dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Renu; Jursinic, Paul A. [Department of Radiation Oncology, West Michigan Cancer Center, 200 North Park Street, Kalamazoo, Michigan 49007 (United States)

    2013-07-15

    Purpose: To show the feasibility of clinical implementation of OSLDs for high dose-rate (HDR) in vivo dosimetry for gynecological and breast patients. To discuss how the OSLDs were characterized for an Ir-192 source, taking into account low gamma energy and high dose gradients. To describe differences caused by the dose calculation formalism of treatment planning systems.Methods: OSLD irradiations were made using the GammaMedplus iX Ir-192 HDR, Varian Medical Systems, Milpitas, CA. BrachyVision versions 8.9 and 10.0, Varian Medical Systems, Milpitas, CA, were used for calculations. Version 8.9 used the TG-43 algorithm and version 10.0 used the Acuros algorithm. The OSLDs (InLight Nanodots) were characterized for Ir-192. Various phantoms were created to assess calculated and measured doses and the angular dependence and self-absorption of the Nanodots. Following successful phantom measurements, patient measurements for gynecological patients and breast cancer patients were made and compared to calculated doses.Results: The OSLD sensitivity to Ir-192 compared to 6 MV is between 1.10 and 1.25, is unique to each detector, and changes with accumulated dose. The measured doses were compared to those predicted by the treatment planning system and found to be in agreement for the gynecological patients to within measurement uncertainty. The range of differences between the measured and Acuros calculated doses was -10%-14%. For the breast patients, there was a discrepancy of -4.4% to +6.5% between the measured and calculated doses at the skin surface when the Acuros algorithm was used. These differences were within experimental uncertainty due to (random) error in the location of the detector with respect to the treatment catheter.Conclusions: OSLDs can be successfully used for HDR in vivo dosimetry. However, for the measurements to be meaningful one must account for the angular dependence, volume-averaging, and the greater sensitivity to Ir-192 gamma rays than to 6 MV x

  9. Feasibility of accelerated partial breast irradiation in a large inner-city public hospital.

    Science.gov (United States)

    Amin, Miral; Gabram, Sheryl; Bumpers, Harvey; Landry, Jerome; Jani, Ashesh B; Diaz, Roberto; Rizzo, Monica

    2012-12-01

    Breast conserving therapy (BCT) that include breast conserving surgery followed by adjuvant radiation therapy has revolutioned medicine by allowing women to avoid mastectomy. Accelerated partial breast irradiation (APBI) has emerged as a valid alternative to whole-breast irradiation that requires a shorter time commitment. We report our novel experience with APBI at a large public hospital that serves low-income and potentially noncompliant patients. A retrospective chart review was conducted of women who underwent BCT for stage 0-IIA breast cancer from August 2007 to August 2010 treated with APBI with a brachytherapy catheter. Twenty-four patients (20 African American) were considered for APBI. Average age was 61 years. Four patients could not undergo APBI for technical reasons and completed whole-breast irradiation over a 5 week period. Median follow-up was 19 months. Nine patients (37.5 %) had ductal carcinoma-in-situ, and 15 patients (62.5 %) had invasive ductal carcinoma with an average tumor size of 1.1 cm. All patients had negative margins of >2 mm. Two patients (8 %) treated with the brachytherapy catheter had in-breast tumor recurrence. Thus, all 24 patients initially identified for APBI successfully completed adjuvant radiotherapy. Patient compliance with postoperative irradiation is key to minimize local recurrence after BCT for breast cancer. This success with a brachytherapy catheter in underserved women in a U.S. public hospital setting indicates that outcomes of compliance and complications are comparable to nationally published results.

  10. Multihelix rotating shield brachytherapy for cervical cancer

    Energy Technology Data Exchange (ETDEWEB)

    Dadkhah, Hossein [Department of Biomedical Engineering, University of Iowa, 1402 Seamans Center for the Engineering Arts and Sciences, Iowa City, Iowa 52242 (United States); Kim, Yusung; Flynn, Ryan T., E-mail: ryan-flynn@uiowa.edu [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Wu, Xiaodong [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 and Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center for the Engineering Arts and Sciences, Iowa City, Iowa 52242 (United States)

    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. A simplified analytical dose calculation algorithm accounting for tissue heterogeneity for low-energy brachytherapy sources

    Science.gov (United States)

    Mashouf, Shahram; Lechtman, Eli; Beaulieu, Luc; Verhaegen, Frank; Keller, Brian M.; Ravi, Ananth; Pignol, Jean-Philippe

    2013-09-01

    The American Association of Physicists in Medicine Task Group No. 43 (AAPM TG-43) formalism is the standard for seeds brachytherapy dose calculation. But for breast seed implants, Monte Carlo simulations reveal large errors due to tissue heterogeneity. Since TG-43 includes several factors to account for source geometry, anisotropy and strength, we propose an additional correction factor, called the inhomogeneity correction factor (ICF), accounting for tissue heterogeneity for Pd-103 brachytherapy. This correction factor is calculated as a function of the media linear attenuation coefficient and mass energy absorption coefficient, and it is independent of the source internal structure. Ultimately the dose in heterogeneous media can be calculated as a product of dose in water as calculated by TG-43 protocol times the ICF. To validate the ICF methodology, dose absorbed in spherical phantoms with large tissue heterogeneities was compared using the TG-43 formalism corrected for heterogeneity versus Monte Carlo simulations. The agreement between Monte Carlo simulations and the ICF method remained within 5% in soft tissues up to several centimeters from a Pd-103 source. Compared to Monte Carlo, the ICF methods can easily be integrated into a clinical treatment planning system and it does not require the detailed internal structure of the source or the photon phase-space.

  12. [Perioperative interstitial brachytherapy for recurrent keloid scars].

    Science.gov (United States)

    Rio, E; Bardet, E; Peuvrel, P; Martinet, L; Perrot, P; Baraer, F; Loirat, Y; Sartre, J-Y; Malard, O; Ferron, C; Dreno, B

    2010-01-01

    Evaluation of the results of perioperative interstitial brachytherapy with low dose-rate (LDR) Ir-192 in the treatment of keloid scars. We performed a retrospective analysis of 73 histologically confirmed keloids (from 58 patients) resistant to medicosurgical treated by surgical excision plus early perioperative brachytherapy. All lesions were initially symptomatic. Local control was evaluated by clinical evaluation. Functional and cosmetic results were assessed in terms of patient responses to a self-administered questionnaire. Median age was 28 years (range 13-71 years). Scars were located as follows: 37% on the face, 32% on the trunk or abdomen, 16% on the neck, and 15% on the arms or legs. The mean delay before loading was four hours (range, 1-6h). The median dose was 20Gy (range, 15-40Gy). Sixty-four scars (from 53 patients) were evaluated. Local control was 86% (follow-up, 44.5 months; range, 14-150 months). All relapses occurred early - within 2 years posttreatment. At 20 months, survival without recurrence was significantly lower when treated lengths were more than 6cm long. The rate was 100% for treated scars below 4.5cm in length, 95% (95% CI: 55-96) for those 4.5-6cm long, and 75% (95% CI: 56-88) beyond 6cm (p=0.038). Of the 35 scars (28 patients) whose results were reassessed, six remained symptomatic and the esthetic results were considered to be good in 51% (18/35) and average in 37% (13/35) (median follow-up, 70 months; range, 16-181 months). Early perioperative LDR brachytherapy delivering 20Gy at 5mm reduced the rate of recurrent keloids resistant to other treatments and gave good functional results. 2009 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  13. Stereotactic radiotherapy as an alternative to plaque brachytherapy in retinoblastoma.

    Science.gov (United States)

    Eldebawy, Eman; Patrocinio, Horacio; Evans, Michael; Hashem, Rania; Nelson, Sylvie; Sidi, Rubina; Freeman, Carolyn

    2010-12-01

    Radioactive plaque brachytherapy has an established role for selected patients with retinoblastoma. Newer non-invasive radiotherapy techniques such as stereotactic conformal radiotherapy (SCR) that uses highly accurate positioning to deliver treatment with small beams may be an interesting alternative to brachytherapy. We report a case treated with SCR and compare the dosimetry with that achievable with brachytherapy. With advantages and disadvantages to both, SCR should more often be considered in the management of RB because of the more homogeneous dose within the target volume and similar or lower doses to surrounding normal tissues.

  14. The application of Geant4 simulation code for brachytherapy treatment

    CERN Document Server

    Agostinelli, S; Garelli, S; Paoli, G; Nieminen, P; Pia, M G

    2000-01-01

    Brachytherapy is a radiotherapeutic modality that makes use of radionuclides to deliver a high radiation dose to a well-defined volume while sparing surrounding healthy structures. At the National Institute for Cancer Research of Genova a High Dose Rate remote afterloading system provides Ir(192) endocavitary brachytherapy treatments. We studied the possibility to use the Geant4 Monte Carlo simulation toolkit in brachytherapy for calculation of complex physical parameters, not directly available by experiment al measurements, used in treatment planning dose deposition models.

  15. Flap reconstruction and interstitial brachytherapy in nonextremity soft tissue sarcoma

    Directory of Open Access Journals (Sweden)

    Goel Vineeta

    2007-01-01

    Full Text Available Radiotherapy is an integral component of management of high-grade soft tissue sarcomas. Interstitial brachytherapy is used to deliver a boost or radical dose with several advantages over external beam radiotherapy. There has always been a concern to use brachytherapy with flap reconstruction of skin defects after wide excision. We preset our initial experience with interstitial brachytherapy in two patients of recurrent high-grade non-extremity sarcomas treated with surgical excision and soft tissue reconstruction of surgical defect.

  16. The American College of Radiology and the American Brachytherapy Society practice parameter for transperineal permanent brachytherapy of prostate cancer.

    Science.gov (United States)

    Bittner, Nathan H J; Orio, Peter F; Merrick, Gregory S; Prestidge, Bradley R; Hartford, Alan Charles; Rosenthal, Seth A

    Transperineal permanent brachytherapy is a safe and effective treatment option for patients with organ-confined prostate cancer. Careful adherence to established brachytherapy standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and the American Brachytherapy Society (ABS) has produced practice parameters for LDR prostate brachytherapy. These practice parameters define the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrist. Factors with respect to patient selection and appropriate use of supplemental treatment modalities such as external beam radiation and androgen suppression therapy are discussed. Logistics with respect to the brachytherapy implant procedure, the importance of dosimetric guidelines, and attention to radiation safety procedures and documentation are presented. Adherence to these parameters can be part of ensuring quality and safety in a successful prostate brachytherapy program. Copyright © 2016 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.

  17. Evaluation of resins for use in brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Luiz Claudio F.M. Garcia; Ferraz, Wilmar Barbosa; Chrcanovic, Bruno Ramos; Santos, Ana Maria M., E-mail: ferrazw@cdtn.b, E-mail: amms@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    Brachytherapy is an advanced cancer treatment where radioactive seeds or sources are placed near or directly into the tumor thus reducing the radiation exposure in the surrounding healthy tissues. Prostate cancer can be treated with interstitial brachytherapy in initial stage of the disease in which tiny radioactive seeds with cylindrical geometry are used. Several kinds of seeds have been developed in order to obtain a better dose distribution around them and with a lower cost manufacturing. These seeds consist of an encapsulation, a radionuclide carrier, and X-ray marker. Among the materials that have potential for innovation in the construction of seeds, biocompatible resins appear as an important option. In this paper, we present some characterization results with Fourier transform infrared spectroscopic (FTIR) and ultraviolet-visible spectroscopy (UV-vis) performed on two types of resins in which curing temperatures for each one were varied as also the results of coatings with these resins under titanium substrates. Interactions of these resins in contact with the simulated body fluid were evaluated by atomic force microscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. (author)

  18. Coatings of nanoparticles applied to brachytherapy treatments

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Andreza A.D.C.C.; Rostelato, Maria Elisa C.M.; Souza, Carla D.; Rodrigues, Bruna T.; Souza, Daiane C.B.; Zeituni, Carlos A.; Nogueira, Beatriz R., E-mail: ccg.andreza@gmail.com, E-mail: elisaros@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-07-01

    Brachytherapy is a treatment for cancer in which the radiation is placed close or in contact with the region to be treated saving the surrounding healthy tissues. Nanotechnology is the science that studies the properties of nanometric materials. Nanobrachytherapy in a new field that unites the advantages of brachytherapy with the small size in the nanoparticle, resulting in an even less invasive treatment. In view of the synthesis of the nanoparticles and their use, there is a fundamental role that is made by the coatings, which not only have the function of avoiding the aggregation of particles, but also stabilize and control their functional properties. Among the range of coatings, the most outstanding are polyethylene glycol (PEG) and gum arabica (GA). PEG improves the surface properties of nanoparticles and presents high stability under biomedical conditions. After the synthesis of gold nanoparticles was developed, PEG and gum arabica were successfully incorporated into the surface. In a vial of pyrex, 1 ml of coating agent and 1 ml of nanoparticles was left under gentle shaking for 2 hours. Incorporation was confirmed by DLS and HRTEM. GA requires further study. (author)

  19. A flattening filter for brachytherapy skin irradiation

    Science.gov (United States)

    Kron, Tomas; Haque, Mamoon; Foulkes, Kristie; Jeraj, Robert

    2002-03-01

    Radioactive sources in close contact offer an alternative to superficial radiation in the treatment of skin lesions. A flattening filter was designed for a lead surface applicator to improve the skin dose distribution of a high dose rate (HDR) brachytherapy unit (Nucletron). At three heights from the opening (10, 15 and 25 mm) of the cylindrical applicator, the 192Ir source can be driven into the centre of the applicator. Thin sheets of lead foil (0.2 mm) were cut into circular shapes and placed in the opening to build a cylindrical cone that acts as a flattening filter. The shape of the cone was optimized in an iterative process using a spreadsheet and the resulting dose distribution under the applicator was determined using radiosensitive film. The use of the filter improved the dose distribution in a plane perpendicular to the beam axis to be within +/-5% of the central axis dose. The present applicator and flattening filter together with an HDR brachytherapy unit offer an alternative for skin irradiation where a superficial unit is not available or will be replaced with a more flexible device. As the depth dose characteristics can be modified using different source-to-surface distances, the dose throughout the patient's skin can be shaped as desired by the radiation oncologist using a compensator design type approach.

  20. A study of brachytherapy for intraocular tumor

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Yung Hoon; Lee, Dong Han; Ko, Kyung Hwan; Lee, Tae Won; Lee, Sung Koo; Choi, Moon Sik [Korea Cancer Center Hospital of Korea Atomic Energy Research Institute, Seoul (Korea, Republic of)

    1994-12-01

    Our purpose of this study is to perform brachytherapy for intraocular tumor. The result were as followed. 1. Eye model was determined as a 25 mm diameter sphere. Ir-192 was considered the most appropriate as radioisotope for brachytherapy, because of the size, half, energy and availability. 2. Considering the biological response with human tissue and protection of exposed dose, we made the plaques with gold, of which size were 15 mm, 17 mm and 20 mm in diameter, and 1.5 mm in thickness. 3. Transmission factor of plaques are all 0.71 with TLD and film dosimetry at the surface of plaques and 0.45, 0.49 at 1.5 mm distance of surface, respectively. 4. As compared the measured data for the plaque with Ir-192 seeds to results of computer dose calculation model by Gary Luxton et al. and CAP-PLAN (Radiation Treatment Planning System), absorbed doses are within {+-}10% and distance deviations are within 0.4 mm. Maximum error is -11.3% and 0.8 mm, respectively. 7 figs, 2 tabs, 28 refs. (Author).

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

    Energy Technology Data Exchange (ETDEWEB)

    Harkenrider, Matthew M., E-mail: mharkenrider@lumc.edu; 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.

  2. Coregistered photoacoustic-ultrasound imaging applied to brachytherapy

    Science.gov (United States)

    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.

  3. Brachytherapy in thetreatment of the oral and oropharyngeal cancer

    Directory of Open Access Journals (Sweden)

    A. M. Zhumankulov

    2015-01-01

    Full Text Available Background. One of the methods of radiotherapy of malignant tumors of oral cavity and oropharyngeal region today is interstitial radiation therapy – brachytherapy, allowing you to create the optimum dose of irradiation to the tumor, necessary for its destruction, without severe radiation reactions in the surrounding tissues unchanged. Brachytherapy has the following advantages: high precision – the ability of the local summarization of high single doses in a limited volume of tissue; good tolerability; a short time of treatment. At this time, brachytherapy is the method of choice used as palliative therapy and as a component of radical treatment.Objective: The purpose of this article is a literature review about the latest achievements of interstitial brachytherapy in malignant tumors of the oral cavity and oropharynx.

  4. Radiotherapy and Brachytherapy : Proceedings of the NATO Advanced Study Institute on Physics of Modern Radiotherapy & Brachytherapy

    CERN Document Server

    Lemoigne, Yves

    2009-01-01

    This volume collects a series of lectures presented at the tenth ESI School held at Archamps (FR) in November 2007 and dedicated to radiotherapy and brachytherapy. The lectures focus on the multiple facets of radiotherapy in general, including external radiotherapy (often called teletherapy) as well as internal radiotherapy (called brachytherapy). Radiotherapy strategy and dose management as well as the decisive role of digital imaging in the associated clinical practice are developed in several articles. Grouped under the discipline of Conformal Radiotherapy (CRT), numerous modern techniques, from Multi-Leaf Collimators (MLC) to Intensity Modulated RadioTherapy (IMRT), are explained in detail. The importance of treatment planning based upon patient data from digital imaging (Computed Tomography) is also underlined. Finally, despite the quasi- totality of patients being presently treated with gamma and X-rays, novel powerful tools are emerging using proton and light ions (like carbon ions) beams, bound to bec...

  5. Electromagnetic tracking for treatment verification in interstitial brachytherapy.

    Science.gov (United States)

    Bert, Christoph; Kellermeier, Markus; Tanderup, Kari

    2016-10-01

    Electromagnetic tracking (EMT) is used in several medical fields to determine the position and orientation of dedicated sensors, e.g., attached to surgical tools. Recently, EMT has been introduced to brachytherapy for implant reconstruction and error detection. The manuscript briefly summarizes the main issues of EMT and error detection in brachytherapy. The potential and complementarity of EMT as treatment verification technology will be discussed in relation to in vivo dosimetry and imaging.

  6. Electromagnetic tracking for treatment verification in interstitial brachytherapy

    Directory of Open Access Journals (Sweden)

    Christoph Bert

    2016-11-01

    Full Text Available Electromagnetic tracking (EMT is used in several medical fields to determine the position and orientation of dedicated sensors, e.g., attached to surgical tools. Recently, EMT has been introduced to brachytherapy for implant reconstruction and error detection. The manuscript briefly summarizes the main issues of EMT and error detection in brachytherapy. The potential and complementarity of EMT as treatment verification technology will be discussed in relation to in vivo dosimetry and imaging.

  7. Electronic brachytherapy management of atypical fibroxanthoma: report of 8 lesions

    OpenAIRE

    Stephen Doggett; James Brazil; Marketa Limova; Leah Press; Sidney Smith; Jeremy Peck

    2017-01-01

    Purpose : To evaluate the suitability of treating atypical fibroxanthoma (AFX), an uncommon skin malignancy, with electronic brachytherapy. Material and methods : From Feb 2013 to Sep 2014, we were referred a total of 8 cases of AFX in 7 patients, all involving the scalp. All of them were treated with electronic brachytherapy 50 Kev radiations (Xoft Axxent®, Fremont, California). All lesions received 40 Gy in two fractions per week with 5mm margins. Results : At a median follow-up...

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

    Science.gov (United States)

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

    2014-03-01

    Brachytherapy with radioactive high dose rate (HDR) (192)Ir 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. 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). 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 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.

  9. Electromagnetic tracking for treatment verification in interstitial brachytherapy

    OpenAIRE

    Christoph Bert; Markus Kellermeier; Kari Tanderup

    2016-01-01

    Electromagnetic tracking (EMT) is used in several medical fields to determine the position and orientation of dedicated sensors, e.g., attached to surgical tools. Recently, EMT has been introduced to brachytherapy for implant reconstruction and error detection. The manuscript briefly summarizes the main issues of EMT and error detection in brachytherapy. The potential and complementarity of EMT as treatment verification technology will be discussed in relation to in vivo dosimetry and imaging.

  10. Breast Cancer and its Radiotherapeutic Methods

    Directory of Open Access Journals (Sweden)

    Banafsheh Zeinali Rafsanjani

    2012-03-01

    Full Text Available Breast cancer is the most common cancer in women after skin cancer. In Iran, the presentation age of this cancer is younger than the global average. There are different therapeutic methods for treatment of breast cancer and the choice of treatment depends on the stage of the disease as well as its type and characteristics. Therapeutic methods include surgery, radiotherapy, and systemic therapies, each consisting of a variety of techniques. The two main surgical techniques are lumpectomy and mastectomy. The main systemic methods are biological therapy (immunotherapy, hormone therapy, and chemotherapy. Radiotherapy is mainly categorized into external-beam radiotherapy and brachytherapy. In this paper, we present a brief review of the different types of breast cancer and their treatments using conventional and modern radiotherapy methods, as well as the treatment efficacy and side effects of breast radiotherapy.

  11. Radiobiological characterization of post-lumpectomy focal brachytherapy with lipid nanoparticle-carried radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Hrycushko, Brian A; Goins, Beth; Yan Weiqiang; Phillips, William T; Otto, Pamela M; Bao, Ande [Department of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX (United States); Gutierrez, Alonso N, E-mail: bao@uthscsa.edu [Department of Radiation Oncology, University of Texas Health Science Center at San Antonio, San Antonio, TX (United States)

    2011-02-07

    Post-operative radiotherapy has commonly been used for early stage breast cancer to treat residual disease. The primary objective of this work was to characterize, through dosimetric and radiobiological modeling, a novel focal brachytherapy technique which uses direct intracavitary infusion of {beta}-emitting radionuclides ({sup 186}Re/{sup 188}Re) carried by lipid nanoparticles (liposomes). Absorbed dose calculations were performed for a spherical lumpectomy cavity with a uniformly injected activity distribution using a dose point kernel convolution technique. Radiobiological indices were used to relate predicted therapy outcome and normal tissue complication of this technique with equivalent external beam radiotherapy treatment regimens. Modeled stromal damage was used as a measure of the inhibition of the stimulatory effect on tumor growth driven by the wound healing response. A sample treatment plan delivering 50 Gy at a therapeutic range of 2.0 mm for {sup 186}Re-liposomes and 5.0 mm for {sup 188}Re-liposomes takes advantage of the dose delivery characteristics of the {beta}-emissions, providing significant EUD (58.2 Gy and 72.5 Gy for {sup 186}Re and {sup 188}Re, respectively) with a minimal NTCP (0.046%) of the healthy ipsilateral breast. Modeling of kidney BED and ipsilateral breast NTCP showed that large injected activity concentrations of both radionuclides could be safely administered without significant complications.

  12. Patient-specific dose calculation methods for high-dose-rate iridium-192 brachytherapy

    Science.gov (United States)

    Poon, Emily S.

    In high-dose-rate 192Ir brachytherapy, the radiation dose received by the patient is calculated according to the AAPM Task Group 43 (TG-43) formalism. This table-based dose superposition method uses dosimetry parameters derived with the radioactive 192Ir source centered in a water phantom. It neglects the dose perturbations caused by inhomogeneities, such as the patient anatomy, applicators, shielding, and radiographic contrast solution. In this work, we evaluated the dosimetric characteristics of a shielded rectal applicator with an endocavitary balloon injected with contrast solution. The dose distributions around this applicator were calculated by the GEANT4 Monte Carlo (MC) code and measured by ionization chamber and GAFCHROMIC EBT film. A patient-specific dose calculation study was then carried out for 40 rectal treatment plans. The PTRAN_CT MC code was used to calculate the dose based on computed tomography (CT) images. This study involved the development of BrachyGUI, an integrated treatment planning tool that can process DICOM-RT data and create PTRAN_CT input initialization files. BrachyGUI also comes with dose calculation and evaluation capabilities. We proposed a novel scatter correction method to account for the reduction in backscatter radiation near tissue-air interfaces. The first step requires calculating the doses contributed by primary and scattered photons separately, assuming a full scatter environment. The scatter dose in the patient is subsequently adjusted using a factor derived by MC calculations, which depends on the distances between the point of interest, the 192Ir source, and the body contour. The method was validated for multicatheter breast brachytherapy, in which the target and skin doses for 18 patient plans agreed with PTRAN_CT calculations better than 1%. Finally, we developed a CT-based analytical dose calculation method. It corrects for the photon attenuation and scatter based upon the radiological paths determined by ray tracing

  13. Comparing digital-light-processing (DLP) and liquid-crystal-on-silicon (LCoS) technologies for high-quality 3D shape measurement

    Science.gov (United States)

    Gong, Chen; Li, Beiwen; Harding, Kevin G.; Zhang, Song

    2014-05-01

    This paper presents a thorough comparison between the digital-light-processing (DLP) technology and liquid-crystal-onsilicon (LCoS) technology on high-quality 3D shape measurement. Specifically, we will study not only each individual color, but also the combination of different color (i.e., white light). The binary defocusing and focused sinusoidal fringe projection methods will be evaluated under all these scenarios. Experimental data demonstrated that for slow speed measurements, DLP has better fringe contrast and thus higher signal to noise ratio (SNR) for better quality 3D shape measurement when the binary defocusing method is employed, or when proper synchronization is present when the focus sinusoidal method is used; and LCoS provides more flexibility for system development when the focus sinusoidal method is employed.

  14. Role of brachytherapy in the treatment of localized prostate cancer

    Directory of Open Access Journals (Sweden)

    A. D. Kaprin

    2015-01-01

    Full Text Available The review is devoted to application of brachytherapy for treating the localized prostate cancer (PC. Statistics for incidence and detectability of this pathology and its dynamics for recent years are represented. Brief analysis of other methods which are conveniently used for treatment of PC, such as radical prostatectomy and external-beam radiotherapy, was performed. Advantages and disadvantages of these methods have been discussed. Brief history about the development of brachytherapy from first experience to wide-spread use in clinical practice is reported. The detailed review of series of large trials from Russia and other countries for efficiency and safety of brachytherapy in patients with prostate cancer for recent 15 years is also represented. Two types of brachytherapy in current clinical oncology i.e. low-dose technique with permanent implantation of microsources and high-dose temporary isotope implantation, specifics of its application in different groups of patients have been described. The procedure of brachytherapy and its three main steps i.e. planning, implantation and control assessment after implantation have been characterized in details. The conclusion about benefits of using of brachytherapy in the treatment of prostate cancer as minimally invasive and efficient method was made. 

  15. Electronic brachytherapy management of atypical fibroxanthoma: report of 8 lesions

    Directory of Open Access Journals (Sweden)

    Stephen Doggett

    2017-01-01

    Full Text Available Purpose : To evaluate the suitability of treating atypical fibroxanthoma (AFX, an uncommon skin malignancy, with electronic brachytherapy. Material and methods : From Feb 2013 to Sep 2014, we were referred a total of 8 cases of AFX in 7 patients, all involving the scalp. All of them were treated with electronic brachytherapy 50 Kev radiations (Xoft Axxent®, Fremont, California. All lesions received 40 Gy in two fractions per week with 5mm margins. Results : At a median follow-up of 23.7 months, the local recurrence rate is 12.5%. The single lesion that failed was not debulked surgically prior to electronic brachytherapy. Conclusions : To our knowledge, this is the first report in the literature on the use of radiation therapy as curative primary treatment for AFX. No contraindication to the use of radiations is found in the literature, with surgery being the sole treatment for AFX noted. Our recurrence rate is 0% for debulked lesions. Risk of recurrence is mitigated with surgical debulking prior to brachytherapy. Electronic brachytherapy appears to be a safe and effective treatment for debulked AFX. Multiple excisions, skin grafting, and wound care can be avoided in elderly patients by the use of electronic brachytherapy.

  16. MO-B-BRC-01: Introduction [Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Prisciandaro, J. [University of Michigan (United States)

    2016-06-15

    Brachytherapy has proven to be an effective treatment option for prostate cancer. Initially, prostate brachytherapy was delivered through permanently implanted low dose rate (LDR) radioactive sources; however, high dose rate (HDR) temporary brachytherapy for prostate cancer is gaining popularity. Needle insertion during prostate brachytherapy is most commonly performed under ultrasound (U/S) guidance; however, treatment planning may be performed utilizing several imaging modalities either in an intra- or post-operative setting. During intra-operative prostate HDR, the needles are imaged during implantation, and planning may be performed in real time. At present, the most common imaging modality utilized for intra-operative prostate HDR is U/S. Alternatively, in the post-operative setting, following needle implantation, patients may be simulated with computed tomography (CT) or magnetic resonance imaging (MRI). Each imaging modality and workflow provides its share of benefits and limitations. Prostate HDR has been adopted in a number of cancer centers across the nation. In this educational session, we will explore the role of U/S, CT, and MRI in HDR prostate brachytherapy. Example workflows and operational details will be shared, and we will discuss how to establish a prostate HDR program in a clinical setting. Learning Objectives: Review prostate HDR techniques based on the imaging modality Discuss the challenges and pitfalls introduced by the three imagebased options for prostate HDR brachytherapy Review the QA process and learn about the development of clinical workflows for these imaging options at different institutions.

  17. A review of the clinical experience in pulsed dose rate brachytherapy

    Science.gov (United States)

    Balgobind, Brian V; Koedooder, Kees; Ordoñez Zúñiga, Diego; Dávila Fajardo, Raquel; Rasch, Coen R N

    2015-01-01

    Pulsed dose rate (PDR) brachytherapy is a treatment modality that combines physical advantages of high dose rate (HDR) brachytherapy with the radiobiological advantages of low dose rate brachytherapy. The aim of this review was to describe the effective clinical use of PDR brachytherapy worldwide in different tumour locations. We found 66 articles reporting on clinical PDR brachytherapy including the treatment procedure and outcome. Moreover, PDR brachytherapy has been applied in almost all tumour sites for which brachytherapy is indicated and with good local control and low toxicity. The main advantage of PDR is, because of the small pulse sizes used, the ability to spare normal tissue. In certain cases, HDR resembles PDR brachytherapy by the use of multifractionated low-fraction dose. PMID:26290399

  18. Radiation recall secondary to adjuvant docetaxel after balloon-catheter based accelerated partial breast irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Nathan W. [Summer Intern, Mayo Clinic Arizona, Scottsdale, AZ (United States); Wong, William W., E-mail: wong.william@mayo.ed [Department of Radiation Oncology, Mayo Clinic Arizona, 13400 E. Shea Boulevard, Scottsdale, AZ 85259 (United States); Karlin, Nina J. [Division of Oncology, Mayo Clinic Arizona, Scottsdale, AZ (United States); Gray, Richard J. [Department of Surgery, Mayo Clinic Arizona, Scottsdale, AZ (United States)

    2010-08-15

    For early stage breast cancer, wide local excision and post-operative whole breast irradiation is a standard treatment. If adjuvant chemotherapy is recommended, radiation is usually given after completion of chemotherapy. In recent years, accelerated partial breast irradiation (APBI) with balloon-cathetered based brachytherapy has become an option for selected patients. For these patients, adjuvant chemotherapy would have to be administered after radiation. The sequence of treatment with radiation followed by chemotherapy results in increased risk of radiation recall reaction (RRD) in these patients. Docetaxel is becoming a more commonly used drug as adjuvant treatment for breast cancer. Here we report a case of docetaxel induced RRD after APBI with balloon-cathetered based brachytherapy. Such reaction would have an adverse impact on the cosmetic outcome and quality of life of the patient. For patients who develop an intense skin reaction after the administration of docetaxel following APBI, RRD should be considered in the differential diagnosis.

  19. 3D shape optimization of fan vanes for multiple operating regimes subject to efficiency and noise-related excellence criteria and constraints

    Directory of Open Access Journals (Sweden)

    Ivo Marinić-Kragić

    2016-01-01

    Full Text Available Fully generic 3D shapes of centrifugal roof fan vanes are explored based on a custom-developed numerical workflow with the ability to vary the vane 3D shape by manipulating the control points of parametric surfaces and change the number of vanes and rotation speed. An excellence formulation is based on design flow efficiency, multi-regime operational conditions and noise criteria for various cases, including multi-objective optimization. Multiple cases of optimization demonstrate the suitability of customized and individualized fan designs for specific working environments according to the selected excellence criteria. Noise analysis is considered as an additional decision-making tool for cases where multiple solutions of equal efficiency are generated and as an additional criteria for multi-objective optimization. The 3D vane shape enables further gains in efficiency compared to 2D shape optimization, while multi-objective optimization with noise as an additional criterion shows potential to greatly reduce the roof fan noise with only small losses in efficiency. The developed workflow which comprises (i a 3D parametric shape modeler, (ii an evolutionary optimizer and (iii a computational fluid dynamics (CFD simulator can be viewed as an integral tool for optimizing the designs of roof fans under custom conditions.

  20. Predictors of Metastatic Disease After Prostate Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Forsythe, Kevin [Department of Radiation Oncology, Mount Sinai School of Medicine, New York, NY (United States); Burri, Ryan [Department of Radiation Oncology, New York-Presbyterian Hospital, New York, NY (United States); Stone, Nelson [Department of Urology, Mount Sinai School of Medicine, New York, NY (United States); Stock, Richard G., E-mail: richard.stock@moutsinai.org [Department of Radiation Oncology, Mount Sinai School of Medicine, New York, NY (United States)

    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

  1. Breast lump

    Science.gov (United States)

    ... removed with surgery. Breast infections are treated with antibiotics. If you are diagnosed with breast cancer , you will discuss your options carefully and thoroughly with your provider. Alternative Names Breast mass Images Female breast Breast lumps ...

  2. Breast lift

    Science.gov (United States)

    Mastopexy; Breast lift with reduction; Breast lift with augmentation ... enlargement with implants) when they have a breast lift. ... it for medical reasons. Women usually have breast lifts to lift sagging, loose breasts. Pregnancy, breastfeeding, and ...

  3. 78 FR 41125 - Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting

    Science.gov (United States)

    2013-07-09

    ... COMMISSION Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting AGENCY...'s permanent implant brachytherapy program. This interim policy affects NRC licensees that are authorized to perform permanent implant brachytherapy. DATES: This policy revision is effective July 9, 2013...

  4. 10 CFR 35.2432 - Records of calibration measurements of brachytherapy sources.

    Science.gov (United States)

    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 the...

  5. Interstitial brachytherapy in carcinoma of the penis

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhary, A.J.; Ghosh, S.; Bhalavat, R.L. [Tata Memorial Hospital, Mumbai (India). Dept. of Radiation Oncology; Kulkarni, J.N. [Tata Memorial Hospital, Mumbai (India). Dept. of Surgery; Sequeira, B.V.E. [Tata Memorial Hospital, Mumbai (India). Dept. of Medical Physics

    1999-01-01

    Aim: Keeping in line with the increasing emphasis on organ preservation, we at the Tata Memorial Hospital have evaluated the role of Ir-192 interstitial implant as regards local control, functional and cosmetic outcome in early as well as locally recurrent carcinoma of the distal penis. Patients and Methods: From October 1988 to December 1996, 23 patients with histopathologically proven cancer of the penis were treated with radical radiation therapy using Ir-192 temporary interstitial implant. Our patients were in the age group of 20 to 60 years. The primary lesions were T1 and 7, T2 in 7 and recurrent in 9 patients. Only 7 patients had palpable groin nodes at presentation, all of which were pathologically negative. The median dose of implant was 50 Gy (range 40 to 60 Gy), using the LDR afterloading system and the Paris system of implant rules for dosimetry. Follow-up ranged from 4 to 117 months (median 24 months). Results: At last follow-up 18 of the 23 patients remained locally controlled with implant alone. Three patients failed only locally, 2 locoregionally and 1 only at the groin. Of the 5 patients who failed locally, 4 were successfully salvaged with partial penectomy and remained controlled when last seen. Local control with implant alone at 8 years was 70% by life table analysis. The patients had excellent functional and cosmetic outcome. We did not record any case of skin or softtissue necrosis. Only 2 patients developed meatal stenosis, both of which were treated endoscopically. Conclusion: Our results lead us to interpret that interstitial brachytherapy with Ir-192 offers excellent local control rates with preservation of organ and function. Penectomy can be reserved as a means for effective salvage. (orig.) [Deutsch] Ziel: Das Prinzip des Organerhalts gewinnt in der Onkologie zunehmend an Bedeutung. Ziel dieser Untersuchung war es, die Rolle der interstitiellen Brachytherapie mit Ir-192 zur Behandlung des fruehen und rezidivierten Peniskarzinoms zu

  6. Epoxy resins used to seal brachytherapy seed

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Natalia Carolina Camargos; Ferraz, Wilmar Barbosa; Reis, Sergio Carneiro dos; Santos, Ana Maria Matildes dos, E-mail: nccf@cdtn.br, E-mail: ferrazw@cdtn.br, E-mail: reissc@cdtn.br, E-mail: amms@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, BH (Brazil)

    2013-07-01

    Prostate cancer treatment with brachytherapy is recommended for patients with cancer at an early stage. In this treatment, small radioactive seeds are implanted directly in the prostate gland. These seeds are composed at least of one radionuclide carrier and an X-ray marker enclosed within a metallic tube usually sealed by laser process. This process is expensive and, furthermore, it can provoke a partial volatilization of the radionuclide and change the isotropy in dose distribution around the seed. In this paper, we present a new sealing process using epoxy resin. Three kinds of resins were utilized and characterized by scanning electron microscopy (SEM), energy dispersive X ray (EDS) and by differential scanning calorimetry (DSC) after immersion in simulated body fluid (SBF) and in sodium iodine solution (NaI). The sealing process showed excellent potential to replace the sealing laser usually employed. (author)

  7. Paddle-based rotating-shield brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yunlong; Xu, Weiyu [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 (United States); Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Buatti, John M. [Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States); Dadkhah, Hossein [Department of Biomedical Engineering, University of Iowa, 1402 Seamans Center, Iowa City, Iowa 52242 (United States); Wu, Xiaodong, E-mail: xiaodong-wu@uiowa.edu [Department of Electrical and Computer Engineering, University of Iowa, 4016 Seamans Center, Iowa City, Iowa 52242 and Department of Radiation Oncology, University of Iowa, 200 Hawkins Drive, Iowa City, Iowa 52242 (United States)

    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

  8. Fast dose optimization for rotating shield brachytherapy.

    Science.gov (United States)

    Cho, Myung; Wu, Xiaodong; Dadkhah, Hossein; Yi, Jirong; Flynn, Ryan T; Kim, Yusung; Xu, Weiyu

    2017-10-01

    To provide a fast computational method, based on the proximal graph solver (POGS) - A convex optimization solver using the alternating direction method of multipliers (ADMM), for calculating an optimal treatment plan in rotating shield brachytherapy (RSBT). RSBT treatment planning has more degrees of freedom than conventional high-dose-rate brachytherapy due to the addition of emission direction, and this necessitates a fast optimization technique to enable clinical usage. The multi-helix RSBT (H-RSBT) delivery technique was investigated for five representative cervical cancer patients. Treatment plans were generated for all patients using the POGS method and the commercially available solver IBM ILOG CPLEX. The rectum, bladder, sigmoid colon, high-risk clinical target volume (HR-CTV), and HR-CTV boundary were the structures included in our optimization, which applied an asymmetric dose-volume optimization with smoothness control. Dose calculation resolution was 1 × 1 × 3 mm3 for all cases. The H-RSBT applicator had 6 helices, with 33.3 mm of translation along the applicator per helical rotation and 1.7 mm spacing between dwell positions, yielding 17.5° emission angle spacing per 5 mm along the applicator. For each patient, HR-CTV D90 , HR-CTV D100 , rectum D2cc , sigmoid D2cc , and bladder D2cc matched within 1% for CPLEX and POGS methods. Also, similar EQD2 values between CPLEX and POGS methods were obtained. POGS was around 18 times faster than CPLEX. For all patients, total optimization times were 32.1-65.4 s for CPLEX and 2.1-3.9 s for POGS. POGS reduced treatment plan optimization time approximately 18 times for RSBT with similar HR-CTV D90 , organ at risk (OAR) D2cc values, and EQD2 values compared to CPLEX, which is significant progress toward clinical translation of RSBT. © 2017 American Association of Physicists in Medicine.

  9. Calibration of Photon Sources for Brachytherapy

    Science.gov (United States)

    Rijnders, Alex

    Source calibration has to be considered an essential part of the quality assurance program in a brachytherapy department. Not only it will ensure that the source strength value used for dose calculation agrees within some predetermined limits to the value stated on the source certificate, but also it will ensure traceability to international standards. At present calibration is most often still given in terms of reference air kerma rate, although calibration in terms of absorbed dose to water would be closer to the users interest. It can be expected that in a near future several standard laboratories will be able to offer this latter service, and dosimetry protocols will have to be adapted in this way. In-air measurement using ionization chambers (e.g. a Baldwin—Farmer ionization chamber for 192Ir high dose rate HDR or pulsed dose rate PDR sources) is still considered the method of choice for high energy source calibration, but because of their ease of use and reliability well type chambers are becoming more popular and are nowadays often recommended as the standard equipment. For low energy sources well type chambers are in practice the only equipment available for calibration. Care should be taken that the chamber is calibrated at the standard laboratory for the same source type and model as used in the clinic, and using the same measurement conditions and setup. Several standard laboratories have difficulties to provide these calibration facilities, especially for the low energy seed sources (125I and 103Pd). Should a user not be able to obtain properly calibrated equipment to verify the brachytherapy sources used in his department, then at least for sources that are replaced on a regular basis, a consistency check program should be set up to ensure a minimal level of quality control before these sources are used for patient treatment.

  10. A modified dose calculation formalism for electronic brachytherapy sources.

    Science.gov (United States)

    DeWerd, Larry A; Culberson, Wesley S; Micka, John A; Simiele, Samantha J

    2015-01-01

    To propose a modification of the current dose calculation formalism introduced in the Task Group No. 43 Report (TG-43) to accommodate an air-kerma rate standard for electronic brachytherapy sources as an alternative to an air-kerma strength standard. Electronic brachytherapy sources are miniature x-ray tubes emitting low energies with high-dose-rates. The National Institute of Standards and Technology (NIST) has introduced a new primary air-kerma rate standard for one of these sources, in contrast to air-kerma strength. A modification of the TG-43 protocol for calculation of dose-rate distributions around electronic brachytherapy sources including sources in an applicator is presented. It cannot be assumed that the perturbations from sources in an applicator are negligible, and thus, the applicator is incorporated in the formalism. The modified protocol mimics the fundamental methodology of the original TG-43 formalism, but now incorporates the new NIST-traceable source strength metric of air-kerma rate at 50 cm and introduces a new subscript, i, to denote the presence of an applicator used in treatment delivery. Applications of electronic brachytherapy sources for surface brachytherapy are not addressed in this Technical Note since they are well documented in other publications. A modification of the AAPM TG-43 protocol has been developed to accommodate an air-kerma rate standard for electronic brachytherapy sources as an alternative to an air-kerma strength standard. The modified TG-43 formalism allows dose calculations to be performed using a new NIST-traceable source strength metric and introduces the concept of applicator-specific formalism parameters denoted with subscript, i. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  11. Skin surface brachytherapy: A survey of contemporary practice patterns.

    Science.gov (United States)

    Likhacheva, Anna O; Devlin, Phillip M; Shirvani, Shervin M; Barker, Christopher A; Beron, Phillip; Bhatnagar, Ajay; Doggett, Stephen W; Hochman, Lawrence; Hsu, Charles; Kasper, Michael; Keisch, Martin; Mutyala, Subhakar; Prestidge, Bradley; Rodriguez Villalba, Silvia; Shukla, Vershalee; Sundararaman, Srinath; Kamrava, Mitchell

    The aim of this study was to define current patterns of care among radiation oncologists who use skin surface brachytherapy for the treatment of cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC) in academic and community settings. A 30-question electronic survey was administered to clinician members of the American Brachytherapy Society. The respondents were asked to provide details regarding their clinical practice and their approach to skin surface brachytherapy. A total of 16 surveys were returned. Among the respondents, aggregate experience varied from 8 to 1800 cases. Most preferred brachytherapy over external beam radiation because of shorter treatment course, conformality of treatment for irregular or curved targets, and shallow dose deposition. Of the total, 60% of respondents routinely estimated lesion depth via ultrasound before initiating treatment. Treatment margin on gross disease varied widely (range, 3-15 mm; median, 5 mm). Hypofractionation was the preferred dose schedule. Prescribed doses ranged from 30 Gy in five fractions to 64 Gy in 32 fractions (EQD2, 40 Gy-65 Gy). There was a tendency to increase the number of fractions for larger targets, although some used the same fractionation regardless of anatomic location or lesion size. There was no consensus on dosimetric constraints, and some respondents reported cases of severe toxicity, particularly when treating the pretibial skin. This pattern of care study suggests that skin brachytherapy can be a convenient and safe tool for treatment of BCC and cSCC. Prospective trials and the development of expert consensus guidelines would be beneficial for optimizing skin surface brachytherapy and reducing practice variation. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  12. The role of brachytherapy in radiation and isotopes centre of Khartoum (RICK)

    CERN Document Server

    Ali, A M

    2000-01-01

    As there are many efforts devoted in order to manage the cancer, here the researcher handle one of these efforts that play a major part in treating the cancer internationally, it is a brachytherapy system. Brachytherapy was carried out mostly with radium sources, but recently some artificial sources are incorporated in this mode of treatment such as Cs-137, Ir-192, Au-198, P-32, Sr-90 and I-125. The research cover history of brachytherapy and radioactive sources used in, techniques of implementation, radiation protection and methods of brachytherapy dose calculation, as well as brachytherapy in radiation and isotopes centre in Khartoum.

  13. Breast Pain

    Science.gov (United States)

    ... result in the development of breast cysts. Breast trauma, prior breast surgery or other factors localized to the breast can lead to breast pain. Breast pain may also start outside the breast — in the chest wall, muscles, joints or heart, for example — and ...

  14. The American College of Radiology and the American Brachytherapy Society practice parameter for the performance of radionuclide-based high-dose-rate brachytherapy.

    Science.gov (United States)

    Erickson, Beth A; Bittner, Nathan H J; Chadha, Manjeet; Mourtada, Firas; Demanes, D Jeffrey

    Brachytherapy is a radiation therapy method in which radionuclide sources are used to deliver a radiation dose at a distance of up to a few centimeters by surface, intracavitary, intraluminal, or interstitial application. This practice parameter refers only to the use of radionuclides for brachytherapy. Brachytherapy alone or combined with external beam therapy plays an important role in the management and treatment of patients with cancer. High-dose-rate (HDR) brachytherapy uses radionuclides such as iridium-192 at dose rates of 20 cGy per minute (12 Gy per hour) or more to a designated target point or volume. High-dose-rate (HDR) brachytherapy is indicated for treating malignant or benign tumors where the treatment volume or targeted points are defined and accessible. Copyright © 2016 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.

  15. Fibroadenoma - breast

    Science.gov (United States)

    ... fibroadenoma; Breast lump - noncancerous; Breast lump - benign References Hacker NF, Friedlander ML. Breast disease: a gynecologic perspective. In: Hacker NF, Gambone JC, Hobel CJ, eds. Hacker and ...

  16. The compressed breast during mammography and breast tomosynthesis: in vivo shape characterization and modeling

    Science.gov (United States)

    Rodríguez-Ruiz, Alejandro; Agasthya, Greeshma A.; Sechopoulos, Ioannis

    2017-09-01

    To characterize and develop a patient-based 3D model of the compressed breast undergoing mammography and breast tomosynthesis. During this IRB-approved, HIPAA-compliant study, 50 women were recruited to undergo 3D breast surface imaging with structured light (SL) during breast compression, along with simultaneous acquisition of a tomosynthesis image. A pair of SL systems were used to acquire 3D surface images by projecting 24 different patterns onto the compressed breast and capturing their reflection off the breast surface in approximately 12-16 s. The 3D surface was characterized and modeled via principal component analysis. The resulting surface model was combined with a previously developed 2D model of projected compressed breast shapes to generate a full 3D model. Data from ten patients were discarded due to technical problems during image acquisition. The maximum breast thickness (found at the chest-wall) had an average value of 56 mm, and decreased 13% towards the nipple (breast tilt angle of 5.2°). The portion of the breast not in contact with the compression paddle or the support table extended on average 17 mm, 18% of the chest-wall to nipple distance. The outermost point along the breast surface lies below the midline of the total thickness. A complete 3D model of compressed breast shapes was created and implemented as a software application available for download, capable of generating new random realistic 3D shapes of breasts undergoing compression. Accurate characterization and modeling of the breast curvature and shape was achieved and will be used for various image processing and clinical tasks.

  17. On the use of particle filters for electromagnetic tracking in high dose rate brachytherapy

    Science.gov (United States)

    Götz, Th I.; Lahmer, G.; Brandt, T.; Kallis, K.; Strnad, V.; Bert, Ch; Hensel, B.; Tomé, A. M.; Lang, E. W.

    2017-10-01

    Modern radiotherapy of female breast cancers often employs high dose rate brachytherapy, where a radioactive source is moved inside catheters, implanted in the female breast, according to a prescribed treatment plan. Source localization relative to the patient’s anatomy is determined with solenoid sensors whose spatial positions are measured with an electromagnetic tracking system. Precise sensor dwell position determination is of utmost importance to assure irradiation of the cancerous tissue according to the treatment plan. We present a hybrid data analysis system which combines multi-dimensional scaling with particle filters to precisely determine sensor dwell positions in the catheters during subsequent radiation treatment sessions. Both techniques are complemented with empirical mode decomposition for the removal of superimposed breathing artifacts. We show that the hybrid model robustly and reliably determines the spatial positions of all catheters used during the treatment and precisely determines any deviations of actual sensor dwell positions from the treatment plan. The hybrid system only relies on sensor positions measured with an EMT system and relates them to the spatial positions of the implanted catheters as initially determined with a computed x-ray tomography.

  18. Dose Modification Factor Analysis of Multi-Lumen Brachytherapy Applicator with Monte Carlo Simulation

    Science.gov (United States)

    Williams, Eric Alan

    Multi-lumen applicators like the Contura (SenoRx, Inc.) are used in partial breast irradiation (PBI) brachytherapy in instances where asymmetric dose distributions are desired, for example, when the applicator surface-to-skin thickness is small (<7mm). In these instances, the air outside the patient and the lung act as a poor scattering medium, scattering less dose back into the breast tissue which affects the dose distribution. Many commercial treatment planning systems do not correct for tissue heterogeneity, which results in inaccuracies in the planned dose distribution. This deviation has been quantified as the dose modification factor (DMF), equal to the ratio of the dose rate at 1cm beyond the applicator surface, with homogenous medium, to the dose rate at 1cm with heterogeneous medium. This investigation intends to model the Contura applicator with the Monte Carlo N-Particle code (MCNP, Los Alamos National Labs), determine a DMF through simulation, and correlate to previous measurements. Taking all geometrical considerations into account, an accurate model of the Contura balloon applicator was created in MCNP. This model was used to run simulations of symmetric and asymmetric plans. The dose modification factor was found to be dependent on the simulated water phantom geometry, with cuboid geometry yielding a max DMF of 1.0664. The same measurements taken using a spherical geometry water phantom gave a DMF of 1.1221. It was also seen that the difference in DMF between symmetric and asymmetric plans using the Contura applicator is minimal.

  19. Progress on system for applying simultaneous heat and brachytherapy to large-area surface disease (Invited Paper)

    Science.gov (United States)

    Stauffer, Paul R.; Schlorff, Jaime L.; Juang, Titania; Neuman, Daniel G., Jr.; Johnson, Jessi E.; Maccarini, Paolo F.; Pouliot, Jean

    2005-04-01

    Laboratory experiments have shown that thermal enhancement of radiation response increases substantially for higher thermal dose (approaching 100 CEM43) and when hyperthermia and radiation are delivered simultaneously. Unfortunately, equipment capable of delivering uniform doses of heat and radiation simultaneously has not been available to test the clinical potential of this approach. We present recent progress on the clinical implementation of a system that combines the uniform heating capabilities of flexible printed circuit board microwave array applicators with an array of brachytherapy catheters held a fixed distance from the skin for uniform radiation of tissue brachytherapy source. The system is based on the Combination Applicator which consists of an array of up to 32 Dual Concentric Conductor (DCC) apertures driven at 915 MHz for heating tissue, coupled with an array of 1 cm spaced catheters for HDR therapy. Efforts to optimize the clinical interface and move from rectangular to more complex shape applicators that accommodate the entire disease in a larger number of patients are described. Improvements to the system for powering and controlling the applicator are also described. Radiation dosimetry and experimental performance results of a prototype 15 x 15 cm dual-purpose applicator demonstrate dose distributions with good homogeneity under large contoured surfaces typical of diffuse chestwall recurrence of breast carcinoma. Investigations of potential interaction between heat and brachytherapy components of a Combination Applicator demonstrate no perceptible perturbation of the heating field from an HDR source or leadwire, no perceptible effect of a scanning HDR source on fiberoptic thermometry, and <0.5% variation of radiation dose delivered through the CMA applicator. By applying heat and radiation simultaneously for maximum synergism of modalities, this dual therapy system should expand the number of patients that can benefit from effective

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

    Science.gov (United States)

    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.

  1. egs_brachy: a versatile and fast Monte Carlo code for brachytherapy

    Science.gov (United States)

    Chamberland, Marc J. P.; Taylor, Randle E. P.; Rogers, D. W. O.; Thomson, Rowan M.

    2016-12-01

    egs_brachy is a versatile and fast Monte Carlo (MC) code for brachytherapy applications. It is based on the EGSnrc code system, enabling simulation of photons and electrons. Complex geometries are modelled using the EGSnrc C++ class library and egs_brachy includes a library of geometry models for many brachytherapy sources, in addition to eye plaques and applicators. Several simulation efficiency enhancing features are implemented in the code. egs_brachy is benchmarked by comparing TG-43 source parameters of three source models to previously published values. 3D dose distributions calculated with egs_brachy are also compared to ones obtained with the BrachyDose code. Well-defined simulations are used to characterize the effectiveness of many efficiency improving techniques, both as an indication of the usefulness of each technique and to find optimal strategies. Efficiencies and calculation times are characterized through single source simulations and simulations of idealized and typical treatments using various efficiency improving techniques. In general, egs_brachy shows agreement within uncertainties with previously published TG-43 source parameter values. 3D dose distributions from egs_brachy and BrachyDose agree at the sub-percent level. Efficiencies vary with radionuclide and source type, number of sources, phantom media, and voxel size. The combined effects of efficiency-improving techniques in egs_brachy lead to short calculation times: simulations approximating prostate and breast permanent implant (both with (2 mm)3 voxels) and eye plaque (with (1 mm)3 voxels) treatments take between 13 and 39 s, on a single 2.5 GHz Intel Xeon E5-2680 v3 processor core, to achieve 2% average statistical uncertainty on doses within the PTV. egs_brachy will be released as free and open source software to the research community.

  2. SU-E-T-169: Characterization of Pacemaker/ICD Dose in SAVI HDR Brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Kalavagunta, C; Lasio, G; Yi, B; Zhou, J; Lin, M [Univ. of Maryland School Of Medicine, Baltimore, MD (United States)

    2015-06-15

    Purpose: It is important to estimate dose to pacemaker (PM)/Implantable Cardioverter Defibrillator (ICD) before undertaking Accelerated Partial Breast Treatment using High Dose Rate (HDR) brachytherapy. Kim et al. have reported HDR PM/ICD dose using a single-source balloon applicator. To the authors knowledge, there have so far not been any published PM/ICD dosimetry literature for the Strut Adjusted Volume Implant (SAVI, Cianna Medical, Aliso Viejo, CA). This study aims to fill this gap by generating a dose look up table (LUT) to predict maximum dose to the PM/ICD in SAVI HDR brachytherapy. Methods: CT scans for 3D dosimetric planning were acquired for four SAVI applicators (6−1-mini, 6−1, 8−1 and 10−1) expanded to their maximum diameter in air. The CT datasets were imported into the Elekta Oncentra TPS for planning and each applicator was digitized in a multiplanar reconstruction window. A dose of 340 cGy was prescribed to the surface of a 1 cm expansion of the SAVI applicator cavity. Cartesian coordinates of the digitized applicator were determined in the treatment leading to the generation of a dose distribution and corresponding distance-dose prediction look up table (LUT) for distances from 2 to 15 cm (6-mini) and 2 to 20 cm (10–1).The deviation between the LUT doses and the dose to the cardiac device in a clinical case was evaluated. Results: Distance-dose look up table were compared to clinical SAVI plan and the discrepancy between the max dose predicted by the LUT and the clinical plan was found to be in the range (−0.44%, 0.74%) of the prescription dose. Conclusion: The distance-dose look up tables for SAVI applicators can be used to estimate the maximum dose to the ICD/PM, with a potential usefulness for quick assessment of dose to the cardiac device prior to applicator placement.

  3. Developing a Verification and Training Phantom for Gynecological Brachytherapy System

    Directory of Open Access Journals (Sweden)

    Mahbobeh Nazarnejad

    2012-03-01

    Full Text Available Introduction Dosimetric accuracy is a major issue in the quality assurance (QA program for treatment planning systems (TPS. An important contribution to this process has been a proper dosimetry method to guarantee the accuracy of delivered dose to the tumor. In brachytherapy (BT of gynecological (Gyn cancer it is usual to insert a combination of tandem and ovoid applicators with a complicated geometry which makes their dosimetry verification difficult and important. Therefore, evaluation and verification of dose distribution is necessary for accurate dose delivery to the patients. Materials and Methods The solid phantom was made from Perspex slabs as a tool for intracavitary brachytherapy dosimetric QA. Film dosimetry (EDR2 was done for a combination of ovoid and tandem applicators introduced by Flexitron brachytherapy system. Treatment planning was also done with Flexiplan 3D-TPS to irradiate films sandwiched between phantom slabs. Isodose curves obtained from treatment planning system and the films were compared with each other in 2D and 3D manners. Results The brachytherapy solid phantom was constructed with slabs. It was possible to insert tandems and ovoids loaded with radioactive source of Ir-192 subsequently. Relative error was 3-8.6% and average relative error was 5.08% in comparison with the films and TPS isodose curves. Conclusion Our results showed that the difference between TPS and the measurements is well within the acceptable boundaries and below the action level according to AAPM TG.45. Our findings showed that this phantom after minor corrections can be used as a method of choice for inter-comparison analysis of TPS and to fill the existing gap for accurate QA program in intracavitary brachytherapy. The constructed phantom also showed that it can be a valuable tool for verification of accurate dose delivery to the patients as well as training for brachytherapy residents and physics students.

  4. Radioactive seed migration following parotid gland interstitial brachytherapy.

    Science.gov (United States)

    Fan, Yi; Huang, Ming-Wei; Zhao, Yi-Jiao; Gao, Hong; Zhang, Jian-Guo

    2017-09-15

    To evaluate the incidence and associated factors of pulmonary seed migration after parotid brachytherapy using a novel migrated seed detection technique. Patients diagnosed with parotid cancer who underwent permanent parotid brachytherapy from January 2006 to December 2011 were reviewed retrospectively. Head and neck CT scans and chest X-rays were evaluated during routine follow-up. Mimics software and Geomagic Studio software were used for seed reconstruction and migrated seed detection from the original implanted region, respectively. Postimplant dosimetry analysis was performed after seeds migration if the seeds were still in their emitting count. Adverse clinical sequelae from seed embolization to the lung were documented. The radioactive seed implants were identified on chest X-rays in 6 patients. The incidence rate of seed migration in 321 parotid brachytherapy patients was 1.87% (6/321) and that of individual seed migration was 0.04% (6/15218 seeds). All migrated seeds were originally from the retromandibular region. No adverse dosimetric consequences were found in the target region. Pulmonary symptoms were not reported by any patient in this study. In our patient set, migration of radioactive seeds with an initial radioactivity of 0.6-0.7 mCi to the chest following parotid brachytherapy was rare. Late migration of a single seed from the central target region did not affect the dosimetry significantly, and patients did not have severe short-term complications. This study proposed a novel technique to localize the anatomical origin of the migrated seeds during brachytherapy. Our evidence suggested that placement of seeds adjacent to blood vessels was associated with an increased likelihood of seed migration to the lungs. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  5. Aspects of dosimetry and clinical practice of skin brachytherapy: The American Brachytherapy Society working group report.

    Science.gov (United States)

    Ouhib, Zoubir; Kasper, Michael; Perez Calatayud, Jose; Rodriguez, Silvia; Bhatnagar, Ajay; Pai, Sujatha; Strasswimmer, John

    2015-01-01

    Nonmelanoma skin cancers (NMSCs) are the most common type of human malignancy. Although surgical techniques are the standard treatment, radiation therapy using photons, electrons, and brachytherapy (BT) (radionuclide-based and electronic) has been an important mode of treatment in specific clinical situations. The purpose of this work is to provide a clinical and dosimetric summary of the use of BT for the treatment of NMSC and to describe the different BT approaches used in treating cutaneous malignancies. A group of experts from the fields of radiation oncology, medical physics, and dermatology, who specialize in managing cutaneous malignancies reviewed the literature and compiled their clinical experience regarding the clinical and dosimetric aspects of skin BT. A dosimetric and clinical review of both high dose rate ((192)Ir) and electronic BT treatment including surface, interstitial, and custom mold applicators is given. Patient evaluation tools such as staging, imaging, and patient selection criteria are discussed. Guidelines for clinical and dosimetric planning, appropriate margin delineation, and applicator selection are suggested. Dose prescription and dose fractionation schedules, as well as prescription depth are discussed. Commissioning and quality assurance requirements are also outlined. Given the limited published data for skin BT, this article is a summary of the limited literature and best practices currently in use for the treatment of NMSC. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

    Hissoiny, Sami; Ozell, Benoit; Despres, Philippe; Carrier, Jean-Francois [Ecole polytechnique de Montreal, Departement de genie informatique et genie logiciel, 2500 chemin de Polytechnique, Montreal, QC, H3T 1J4 (Canada); Departement de radio-oncologie, Centre hospitalier universitaire de Quebec (CHUQ), 11 Cote du Palais, Quebec, QC, G1R 2J6 (Canada); Departement de physique, Universite de Montreal, Montreal, QC (Canada) and Departement de radio-oncologie and Centre de recherche du CHUM, Centre hospitalier de l' Universite de Montreal (CHUM), Montreal, QC, H2L 4M1 (Canada)

    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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  9. The difference of scoring dose to water or tissues in Monte Carlo dose calculations for low energy brachytherapy photon sources

    Energy Technology Data Exchange (ETDEWEB)

    Landry, Guillaume; Reniers, Brigitte; Pignol, Jean-Philippe; Beaulieu, Luc; Verhaegen, Frank [Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands); Department of Radiation Oncology, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario M4N 3M5 (Canada); Departement de Radio-Oncologie et Centre de Recherche en Cancerologie, Universite Laval, CHUQ Pavillon L' Hotel-Dieu de Quebec, Quebec G1R 2J6 (Canada) and Departement de Physique, de Genie Physique et d' Optique, Universite Laval, Quebec G1K 7P4 (Canada); Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht 6201 BN (Netherlands) and Department of Oncology, McGill University, Montreal General Hospital, Montreal, Quebec H3G 1A4 (Canada)

    2011-03-15

    Purpose: The goal of this work is to compare D{sub m,m} (radiation transported in medium; dose scored in medium) and D{sub w,m} (radiation transported in medium; dose scored in water) obtained from Monte Carlo (MC) simulations for a subset of human tissues of interest in low energy photon brachytherapy. Using low dose rate seeds and an electronic brachytherapy source (EBS), the authors quantify the large cavity theory conversion factors required. The authors also assess whether applying large cavity theory utilizing the sources' initial photon spectra and average photon energy induces errors related to spatial spectral variations. First, ideal spherical geometries were investigated, followed by clinical brachytherapy LDR seed implants for breast and prostate cancer patients. Methods: Two types of dose calculations are performed with the GEANT4 MC code. (1) For several human tissues, dose profiles are obtained in spherical geometries centered on four types of low energy brachytherapy sources: {sup 125}I, {sup 103}Pd, and {sup 131}Cs seeds, as well as an EBS operating at 50 kV. Ratios of D{sub w,m} over D{sub m,m} are evaluated in the 0-6 cm range. In addition to mean tissue composition, compositions corresponding to one standard deviation from the mean are also studied. (2) Four clinical breast (using {sup 103}Pd) and prostate (using {sup 125}I) brachytherapy seed implants are considered. MC dose calculations are performed based on postimplant CT scans using prostate and breast tissue compositions. PTV D{sub 90} values are compared for D{sub w,m} and D{sub m,m}. Results: (1) Differences (D{sub w,m}/D{sub m,m}-1) of -3% to 70% are observed for the investigated tissues. For a given tissue, D{sub w,m}/D{sub m,m} is similar for all sources within 4% and does not vary more than 2% with distance due to very moderate spectral shifts. Variations of tissue composition about the assumed mean composition influence the conversion factors up to 38%. (2) The ratio of D

  10. SU-F-T-537: Prone Breast Accelerated Partial Breast Irradiation Using Non-Coplanar Volumetric Arc Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Beninati, G; Barbiere, J; Godfrey, L; Ndlovu, A [Hackensack University Medical Center, Hackensack, NJ (United States)

    2016-06-15

    Purpose: To demonstrate that Volumetric Modulated Arc Therapy (VMAT) can be an alternative technique to Brachytherapy Accelerated Partial Breast Irradiation (APBI) for treating large breasted women. The non-coplanar VMAT technique uses a commercially available couch and a small number of angles. This technique with the patient in the prone position can reduce high skin and critical structure doses in large breasted women, which are usually associated with Brachytherapy APBI. Methods: Philips Pinnacle treatment planning system with Smart Arc was used to plan a left sided laterally located excision cavity on a standard prone breast patient setup. Three thirty-degree arcs entered from the lateral side at respective couch angles of 345, 0, and 15 degrees. A fourth thirty degree arc beam entered from the medial side at a couch angle of 0 degrees. The arcs were selected to avoid critical structures as much as possible. A test run was then performed to verify that the beams did not collide with the patient nor support structures. NSABP B-39/RTOG 0413 protocol guidelines were used for dose prescription, normal tissue, and target definition. Results: Dose Volume Histogram analysis indicated that all parameters were equal or better than RTOG recommendations. Of particular note regarding the plan quality:1.(a) For a prescribed dose of 3850cGy the PTV-EVAL target volume receiving 100 percent of the dose(V100) was 93; protocol recommendation is V90 > 90 percent. (b) Maximum dose was 110 percent versus the allowed 120 percent .2. Uninvolved percentage of normal breast V100 and V50 were 17 and 47 versus allowed 35 and 60 percent respectively.3. For the skin, V100 was 5.7cc and the max dose to 0.1 cc was 4190cGy. Conclusion: Prone Breast non-coplanar VMAT APBI can achieve better skin cosmesis and lower critical structure doses than Brachytherapy APBI.

  11. Lead-oriented synthesis: Investigation of organolithium-mediated routes to 3-D scaffolds and 3-D shape analysis of a virtual lead-like library.

    Science.gov (United States)

    Lüthy, Monique; Wheldon, Mary C; Haji-Cheteh, Chehasnah; Atobe, Masakazu; Bond, Paul S; O'Brien, Peter; Hubbard, Roderick E; Fairlamb, Ian J S

    2015-06-01

    Synthetic routes to six 3-D scaffolds containing piperazine, pyrrolidine and piperidine cores have been developed. The synthetic methodology focused on the use of N-Boc α-lithiation-trapping chemistry. Notably, suitably protected and/or functionalised medicinal chemistry building blocks were synthesised via concise, connective methodology. This represents a rare example of lead-oriented synthesis. A virtual library of 190 compounds was then enumerated from the six scaffolds. Of these, 92 compounds (48%) fit the lead-like criteria of: (i) -1⩽AlogP⩽3; (ii) 14⩽number of heavy atoms⩽26; (iii) total polar surface area⩾50Å(2). The 3-D shapes of the 190 compounds were analysed using a triangular plot of normalised principal moments of inertia (PMI). From this, 46 compounds were identified which had lead-like properties and possessed 3-D shapes in under-represented areas of pharmaceutical space. Thus, the PMI analysis of the 190 member virtual library showed that whilst scaffolds which may appear on paper to be 3-D in shape, only 24% of the compounds actually had 3-D structures in the more interesting areas of 3-D drug space. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Full-frame, high-speed 3D shape and deformation measurements using stereo-digital image correlation and a single color high-speed camera

    Science.gov (United States)

    Yu, Liping; Pan, Bing

    2017-08-01

    Full-frame, high-speed 3D shape and deformation measurement using stereo-digital image correlation (stereo-DIC) technique and a single high-speed color camera is proposed. With the aid of a skillfully designed pseudo stereo-imaging apparatus, color images of a test object surface, composed of blue and red channel images from two different optical paths, are recorded by a high-speed color CMOS camera. The recorded color images can be separated into red and blue channel sub-images using a simple but effective color crosstalk correction method. These separated blue and red channel sub-images are processed by regular stereo-DIC method to retrieve full-field 3D shape and deformation on the test object surface. Compared with existing two-camera high-speed stereo-DIC or four-mirror-adapter-assisted singe-camera high-speed stereo-DIC, the proposed single-camera high-speed stereo-DIC technique offers prominent advantages of full-frame measurements using a single high-speed camera but without sacrificing its spatial resolution. Two real experiments, including shape measurement of a curved surface and vibration measurement of a Chinese double-side drum, demonstrated the effectiveness and accuracy of the proposed technique.

  13. High-beta analytic equilibria in circular, elliptical, and D-shaped large aspect ratio axisymmetric configurations with poloidal and toroidal flows

    Science.gov (United States)

    López, O. E.; Guazzotto, L.

    2017-03-01

    The Grad-Shafranov-Bernoulli system of equations is a single fluid magnetohydrodynamical description of axisymmetric equilibria with mass flows. Using a variational perturbative approach [E. Hameiri, Phys. Plasmas 20, 024504 (2013)], analytic approximations for high-beta equilibria in circular, elliptical, and D-shaped cross sections in the high aspect ratio approximation are found, which include finite toroidal and poloidal flows. Assuming a polynomial dependence of the free functions on the poloidal flux, the equilibrium problem is reduced to an inhomogeneous Helmholtz partial differential equation (PDE) subject to homogeneous Dirichlet conditions. An application of the Green's function method leads to a closed form for the circular solution and to a series solution in terms of Mathieu functions for the elliptical case, which is valid for arbitrary elongations. To extend the elliptical solution to a D-shaped domain, a boundary perturbation in terms of the triangularity is used. A comparison with the code FLOW [L. Guazzotto et al., Phys. Plasmas 11(2), 604-614 (2004)] is presented for relevant scenarios.

  14. Polarization detection analysis of dual-channel surface plasmon resonance sensing for silicone oils based on the D-shaped fiber with a central hole

    Science.gov (United States)

    Xia, Li; Shuai, Binbin; Li, Wei; Liu, Deming

    2012-08-01

    We present and numerically characterize a dual channel surface plasmon resonance (SPR) sensor based on a D-shaped fiber with a central hole for silicone oil detections. The proposed design incorporates two metalized channels to facilitate the simultaneous detection of one group of silicone oils, which can consist of two different species. It has been demonstrated that the p-polarized input light can induce two peaks among surface plasmon resonance places, which come from the coupling between the core-guided mode and the fundamental surface plasmon polariton (SPP) modes at the D-shaped surface and around the central hole surface. However, the s-polarized input light can only induce one peak among surface plasmon resonance places, which comes from the coupling between the core-guided mode and the fundamental SPP mode around the central hole surface. The simulation results show that the characteristic responses of two channels independently correspond to the refractive index variations in the silicone oils with which they are in contact. A maximum sensitivity of 3500 nm/RIU (refractive index unit) and 4400 nm/RIU are achieved for channel A and B, respectively. This kind of sensor structure and polarization related demodulation method is promising in the simultaneous multi-analytes sensing applications in the future.

  15. 3DMADMAC|SPECTRAL: Hardware and Software Solution for Integrated Digitization of 3D Shape, Multispectral Color and BRDF for Cultural Heritage Documentation

    Directory of Open Access Journals (Sweden)

    Robert Sitnik

    2011-12-01

    Full Text Available In this article a new 3D measurement system along with the study on 3D printing technology is presented from the perspective of quality of reproduction. In the first part of the paper the 3DMADMAC|SPECTRAL system which integrates 3D shape with additional color and angular reflectance measurement capabilities is presented (see Figure 1. The shape measurement system is based on structured light projection with the use of a DLP projector. The 3D shape measurement method is based on sinusoidal fringes and Gray codes projection. Color is being measured using multispectral images with a set of interference filters to separate spectral channels. Additionally the set up includes an array of compact light sources for measuring angular reflectance based on image analysis and 3D data processing. All three components of the integrated system use the same greyscale camera as a detector. The purpose of the system is to obtain complete information about shape, color and reflectance characteristic of mea sured surface, especially for cultural heritage objects - in order to create high quality 3D documentation. In the second part of the paper the 3D printing technology will be tested on real measured cultural heritage objects. Tests allow to assess measurement and color accuracy of reproduction by selected 3D printing technology and shed some light on how current 3D printing technology can be applied into cultural heritage.

  16. Endoluminal brachytherapy for recurrent laryngeal carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Latham, M.M. [Sir Charles Gairdner Hospital, Perth, WA, (Australia). Dept of Radiotherapy; Smart, G.P.; Hedland-Thomas, B. [Royal Perth Hospital, WA, (Australia). Dept of Medical Physics; Harper, C.S. [Royal Perth Hospital, WA (Australia). Radiation Oncology Centre

    1997-11-01

    Early-stage squamous cell carcinoma of the larynx is usually treated with local field radiotherapy. Surgery is used for salvage following recurrence. Further recurrences present a more difficult therapeutic problem which requires individualized management. The aims of local control, survival, maintenance of function and minimizing side effects all need to be balanced according to the site and extent of disease. The present case study looks at the management of a 54-year-old man with multiple recurrences from a squamous cell carcinoma of the larynx. It describes a technique of endoluminal brachytherapy using an iridium-192 wire spiraled around the outer part of a tracheotomy tube that achieves good local control while enabling self-insertion and self-cleaning during the procedure. The dose given was 2500 cGy at 5 mm over 25.2 h and was achieved with minimal early or delayed side effects. The patient had no further symptoms relating to the stomal recurrence until his death from metastatic disease 6 months later. (authors). 8 refs., 3 figs.

  17. American College of Radiology-American Brachytherapy Society practice parameter for electronically generated low-energy radiation sources.

    Science.gov (United States)

    Devlin, Phillip M; Gaspar, Laurie E; Buzurovic, Ivan; Demanes, D Jeffrey; Kasper, Michael E; Nag, Subir; Ouhib, Zoubir; Petit, Joshua H; Rosenthal, Seth A; Small, William; Wallner, Paul E; Hartford, Alan C

    This collaborative practice parameter technical standard has been created between the American College of Radiology and American Brachytherapy Society to guide the usage of electronically generated low energy radiation sources (ELSs). It refers to the use of electronic X-ray sources with peak voltages up to 120 kVp to deliver therapeutic radiation therapy. The parameter provides a guideline for utilizing ELS, including patient selection and consent, treatment planning, and delivery processes. The parameter reviews the published clinical data with regard to ELS results in skin, breast, and other cancers. This technical standard recommends appropriate qualifications of the involved personnel. The parameter reviews the technical issues relating to equipment specifications as well as patient and personnel safety. Regarding suggestions for educational programs with regard to this parameter,it is suggested that the training level for clinicians be equivalent to that for other radiation therapies. It also suggests that ELS must be done using the same standards of quality and safety as those in place for other forms of radiation therapy. Copyright © 2017 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.

  18. Three dimensional intensity modulated brachytherapy (IMBT): Dosimetry algorithm and inverse treatment planning

    Energy Technology Data Exchange (ETDEWEB)

    Shi Chengyu; Guo Bingqi; Cheng, Chih-Yao; Esquivel, Carlos; Eng, Tony; Papanikolaou, Niko [Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229 (United States); Department of Radiation Oncology, Oklahoma University Health Science Center, Oklahoma City, Oklahoma 73104 (United States); Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229 (United States)

    2010-07-15

    Purpose: The feasibility of intensity modulated brachytherapy (IMBT) to improve dose conformity for irregularly shaped targets has been previously investigated by researchers by means of using partially shielded sources. However, partial shielding does not fully explore the potential of IMBT. The goal of this study is to introduce the concept of three dimensional (3D) intensity modulated brachytherapy and solve two fundamental issues regarding the application of 3D IMBT treatment planning: The dose calculation algorithm and the inverse treatment planning method. Methods: A 3D IMBT treatment planning system prototype was developed using the MATLAB platform. This system consists of three major components: (1) A comprehensive IMBT source calibration method with dosimetric inputs from Monte Carlo (EGSnrc) simulations; (2) a ''modified TG-43'' (mTG-43) dose calculation formalism for IMBT dosimetry; and (3) a physical constraint based inverse IMBT treatment planning platform utilizing a simulated annealing optimization algorithm. The model S700 Axxent electronic brachytherapy source developed by Xoft, Inc. (Fremont, CA), was simulated in this application. Ten intracavitary accelerated partial breast irradiation (APBI) cases were studied. For each case, an ''isotropic plan'' with only optimized source dwell time and a fully optimized IMBT plan were generated and compared to the original plan in various dosimetric aspects, such as the plan quality, planning, and delivery time. The issue of the mechanical complexity of the IMBT applicator is not addressed in this study. Results: IMBT approaches showed superior plan quality compared to the original plans and the isotropic plans to different extents in all studied cases. An extremely difficult case with a small breast and a small distance to the ribs and skin, the IMBT plan minimized the high dose volume V{sub 200} by 16.1% and 4.8%, respectively, compared to the original and the

  19. The Adoption of New Adjuvant Radiation Therapy Modalities Among Medicare Beneficiaries With Breast Cancer: Clinical Correlates and Cost Implications

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, Kenneth B. [Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center, Yale Comprehensive Cancer Center and Yale University School of Medicine, New Haven, Connecticut (United States); Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Soulos, Pamela R. [Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center, Yale Comprehensive Cancer Center and Yale University School of Medicine, New Haven, Connecticut (United States); Section of General Internal Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut (United States); Herrin, Jeph [Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center, Yale Comprehensive Cancer Center and Yale University School of Medicine, New Haven, Connecticut (United States); Health Research and Educational Trust, Chicago, Illinois (United States); Yu, James B. [Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center, Yale Comprehensive Cancer Center and Yale University School of Medicine, New Haven, Connecticut (United States); Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, Connecticut (United States); Long, Jessica B. [Cancer Outcomes, Public Policy, and Effectiveness Research (COPPER) Center, Yale Comprehensive Cancer Center and Yale University School of Medicine, New Haven, Connecticut (United States); Section of General Internal Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut (United States); Dostaler, Edward [Section of General Internal Medicine, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut (United States); and others

    2013-04-01

    Purpose: New radiation therapy modalities have broadened treatment options for older women with breast cancer, but it is unclear how clinical factors, geographic region, and physician preference affect the choice of radiation therapy modality. Methods and Materials: We used the Surveillance, Epidemiology, and End Results-Medicare database to identify women diagnosed with stage I-III breast cancer from 1998 to 2007 who underwent breast-conserving surgery. We assessed the temporal trends in, and costs of, the adoption of intensity modulated radiation therapy (IMRT) and brachytherapy. Using hierarchical logistic regression, we evaluated the relationship between the use of these new modalities and patient and regional characteristics. Results: Of 35,060 patients, 69.9% received conventional external beam radiation therapy (EBRT). Although overall radiation therapy use remained constant, the use of IMRT increased from 0.0% to 12.6% from 1998 to 2007, and brachytherapy increased from 0.7% to 9.0%. The statistical variation in brachytherapy use attributable to the radiation oncologist and geographic region was 41.4% and 9.5%, respectively (for IMRT: 23.8% and 22.1%, respectively). Women undergoing treatment at a free-standing radiation facility were significantly more likely to receive IMRT than were women treated at a hospital-based facility (odds ratio for IMRT vs EBRT: 3.89 [95% confidence interval, 2.78-5.45]). No such association was seen for brachytherapy. The median radiation therapy cost per treated patient increased from $5389 in 2001 to $8539 in 2007. Conclusions: IMRT and brachytherapy use increased substantially from 1998 to 2007; overall, radiation therapy costs increased by more than 50%. Radiation oncologists played an important role in treatment choice for both types of radiation therapy, whereas geographic region played a bigger role in the use of IMRT than brachytherapy.

  20. Projected Improvements in Accelerated Partial Breast Irradiation Using a Novel Breast Stereotactic Radiotherapy Device: A Dosimetric Analysis.

    Science.gov (United States)

    Snider, James W; Mutaf, Yildirim; Nichols, Elizabeth; Hall, Andrea; Vadnais, Patrick; Regine, William F; Feigenberg, Steven J

    2017-01-01

    Accelerated partial breast irradiation has caused higher than expected rates of poor cosmesis. At our institution, a novel breast stereotactic radiotherapy device has demonstrated dosimetric distributions similar to those in brachytherapy. This study analyzed comparative dose distributions achieved with the device and intensity-modulated radiation therapy accelerated partial breast irradiation. Nine patients underwent computed tomography simulation in the prone position using device-specific immobilization on an institutional review board-approved protocol. Accelerated partial breast irradiation target volumes (planning target volume_10mm) were created per the National Surgical Adjuvant Breast and Bowel Project B-39 protocol. Additional breast stereotactic radiotherapy volumes using smaller margins (planning target volume_3mm) were created based on improved immobilization. Intensity-modulated radiation therapy and breast stereotactic radiotherapy accelerated partial breast irradiation plans were separately generated for appropriate volumes. Plans were evaluated based on established dosimetric surrogates of poor cosmetic outcomes. Wilcoxon rank sum tests were utilized to contrast volumes of critical structures receiving a percentage of total dose ( Vx). The breast stereotactic radiotherapy device consistently reduced dose to all normal structures with equivalent target coverage. The ipsilateral breast V20-100 was significantly reduced ( P irradiation in this series indicate a potential to improve outcomes. Clinical trials investigating this benefit have begun accrual.

  1. Spinal anaesthesia for brachytherapy for carcinoma of the cervix: a ...

    African Journals Online (AJOL)

    Setting and subjects: Forty female patients, presenting to Groote Schuur Hospital for brachytherapy for carcinoma of the cervix, were randomised to receive either 5 mg or 9 mg (1 ml or 1.8 ml) of 0.5% hyperbaric bupivacaine, plus 15 μg fentanyl via the L3/L4 interspace. Results: Patients receiving the lower dose could be ...

  2. Electromagnetic tracking for treatment verification in interstitial brachytherapy

    DEFF Research Database (Denmark)

    Bert, Christoph; Kellermeier, Markus; Tanderup, Kari

    2016-01-01

    Electromagnetic tracking (EMT) is used in several medical fields to determine the position and orientation of dedicated sensors, e.g., attached to surgical tools. Recently, EMT has been introduced to brachytherapy for implant reconstruction and error detection. The manuscript briefly summarizes...

  3. Factors influencing outcome of I-125 prostate cancer brachytherapy

    NARCIS (Netherlands)

    Hinnen, K.A.

    2011-01-01

    Brachytherapy is becoming an increasingly popular prostate cancer treatment, probably due to the specific advantages of the procedure, such as the minimal invasiveness and the lower chance of impotence and incontinence. Nonetheless, because of the long follow-up that is required to obtain prostate

  4. Calculation of the Transit Dose in HDR Brachytherapy Based on ...

    African Journals Online (AJOL)

    The Monte Carlo method, which is the gold standard for accurate dose calculations in radiotherapy, was used to obtain the transit doses around a high dose rate (HDR) brachytherapy implant with thirteen dwell points. The midpoints of each of the inter-dwell separations, of step size 0.25 cm, were representative of the ...

  5. Brachytherapy optimal planning with application to intravascular radiation therapy

    DEFF Research Database (Denmark)

    Sadegh, Payman; Mourtada, Firas A.; Taylor, Russell H.

    1999-01-01

    . Dose rate calculations are based on the sosimetry formulation of the American Association of Physicists in Medicine, Task Group 43. We apply the technique to optimal planning for intravascular brachytherapy of intimal hyperplasia using ultrasound data and 192Ir seeds. The planning includes...

  6. In vivo dosimetry: trends and prospects for brachytherapy

    DEFF Research Database (Denmark)

    Kertzscher, Gustavo; Rosenfeld, A.; Beddar, S.

    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...

  7. Transit dose calculation in high dose rate brachytherapy (HDR ...

    African Journals Online (AJOL)

    Transit doses around a high dose rate 192Ir brachytherapy source were calculated using Sievert Integral at positions where the moving source was located exactly between two adjacent dwell positions. The correspond-ing transit dose rates were obtained by using energy absorption coefficients. Discrete step sizes of 0.25 ...

  8. Pulsed dose rate brachytherapy – is it the right way?

    Directory of Open Access Journals (Sweden)

    Janusz Skowronek

    2010-10-01

    Full Text Available Pulsed dose rate (PDR-BT treatment is a brachytherapy modality that combines physical advantages of high-doserate (HDR-BT technology (isodose optimization, radiation safety with the radiobiological advantages of low-dose-rate (LDR-BT brachytherapy. Pulsed brachytherapy consists of using stronger radiation source than for LDR-BT and producing series of short exposures of 10 to 30 minutes in every hour to approximately the same total dose in the sameoverall time as with the LDR-BT. Modern afterloading equipment offers certain advantages over interstitial or intracavitaryinsertion of separate needles, tubes, seeds or wires. Isodose volumes in tissues can be created flexibly by a combinationof careful placement of the catheter and the adjustment of the dwell times of the computerized stepping source.Automatic removal of the radiation sources into a shielded safe eliminates radiation exposures to staff and visitors.Radiation exposure is also eliminated to the staff who formerly loaded and unloaded multiplicity of radioactive sources into the catheters, ovoids, tubes etc. This review based on summarized clinical investigations, analyses the feasibility and the background to introduce this brachytherapy technique and chosen clinical applications of PDR-BT.

  9. Comparative dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Brandao, Samia de Freitas, E-mail: samiabrandao@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Campos, Tarcisio Passos Ribeiro de [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

    2013-06-15

    Objective: comparative analysis of dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for treatment of brain tumors. Materials and methods: simulations of intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT were performed with the MCNP5 code, modeling the treatment of a brain tumor on a voxel computational phantom representing a human head. Absorbed dose rates were converted into biologically weighted dose rates. Results: intracavitary balloon catheter brachytherapy with I-125 produced biologically weighted mean dose rates of 3.2E-11, 1.3E-10, 1.9E-11 and 6.9E-13 RBE.Gy.h{sup -1}.p{sup -1}.s, respectively, on the healthy tissue, on the balloon periphery and on the /{sub 1} and /{sub 2} tumor infiltration zones. On the other hand, Cf-252 brachytherapy combined with BNCT produced a biologically weighted mean dose rate of 5.2E-09, 2.3E-07, 8.7E-09 and 2.4E-09 RBE.Gy.h{sup -1}.p{sup -1}.s, respectively on the healthy tissue, on the target tumor and on the /{sub 1} and /{sub 2} infiltration zones. Conclusion: Cf-252 brachytherapy combined with BNCT delivered a selective irradiation to the target tumor and to infiltration zones, while intracavitary balloon catheter brachytherapy with I-125 delivered negligible doses on the tumor infiltration zones. (author)

  10. Comparative dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for brain tumors

    Directory of Open Access Journals (Sweden)

    Samia de Freitas Brandao

    2013-07-01

    Full Text Available Objective Comparative analysis of dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for treatment of brain tumors. Materials and Methods Simulations of intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT were performed with the MCNP5 code, modeling the treatment of a brain tumor on a voxel computational phantom representing a human head. Absorbed dose rates were converted into biologically weighted dose rates. Results Intracavitary balloon catheter brachytherapy with I-125 produced biologically weighted mean dose rates of 3.2E-11, 1.3E-10, 1.9E-11 and 6.9E-13 RBE.Gy.h-1.p-1.s, respectively, on the healthy tissue, on the balloon periphery and on the I 1 and I 2 tumor infiltration zones. On the other hand, Cf-252 brachytherapy combined with BNCT produced a biologically weighted mean dose rate of 5.2E-09, 2.3E-07, 8.7E-09 and 2.4E-09 RBE.Gy.h-1.p-1.s, respectively on the healthy tissue, on the target tumor and on the I 1 and I 2 infiltration zones. Conclusion Cf-252 brachytherapy combined with BNCT delivered a selective irradiation to the target tumor and to infiltration zones, while intracavitary balloon catheter brachytherapy with I-125 delivered negligible doses on the tumor infiltration zones.

  11. Brachytherapy dose measurements in heterogeneous tissues

    Energy Technology Data Exchange (ETDEWEB)

    Paiva F, G.; Luvizotto, J.; Salles C, T.; Guimaraes A, P. C.; Dalledone S, P. de T.; Yoriyaz, H. [Instituto de Pesquisas Energeticas e Nucleares / CNEN, Av. Lineu Prestes 2242, Cidade Universitaria, 05508-000 Sao Paulo (Brazil); Rubo, R., E-mail: gabrielpaivafonseca@gmail.com [Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo, 05403-900 Sao Paulo (Brazil)

    2014-08-15

    Recently, Beau lieu et al. published an article providing guidance for Model-Based Dose Calculation Algorithms (MBDCAs), where tissue heterogeneity considerations are addressed. It is well-known that T G-43 formalism which considers only water medium is limited and significant dose differences have been found comparing both methodologies. The aim of the present work is to experimentally quantify dose values in heterogeneous medium using different dose measurement methods and techniques and compare them with those obtained with Monte Carlo simulations. Experiments have been performed using a Nucletron micro Selectron-Hdr Ir-192 brachytherapy source and a heterogeneous phantom composed by PMMA and different tissue equivalent cylinders like bone, lungs and muscle. Several dose measurements were obtained using tissue equivalent materials with height 1.8 cm and 4.3 cm positioned between the radiation source and the detectors. Radiochromic films, TLDs and MOSFET S have been used for the dose measurements. Film dosimetry has been performed using two methodologies: a) linearization for dose-response curve based on calibration curves to create a functional form that linearize s the dose response and b) 177 multichannel analysis dosimetry where the multiple color channels are analyzed allowing to address not only disturbances in the measurements caused by thickness variation in the film layer, but also, separate other external influences in the film response. All experiments have been simulated using the MCNP5 Monte Carlo radiation transport code. Comparison of experimental results are in good agreement with calculated dose values with differences less than 6% for almost all cases. (Author)

  12. Dose optimisation in single plane interstitial brachytherapy.

    Science.gov (United States)

    Tanderup, Kari; Hellebust, Taran Paulsen; Honoré, Henriette Benedicte; Nielsen, Søren Kynde; Olsen, Dag Rune; Grau, Cai; Lindegaard, Jacob Christian

    2006-10-01

    Brachytherapy dose distributions can be optimised by modulation of source dwell times. In this study dose optimisation in single planar interstitial implants was evaluated in order to quantify the potential benefit in patients. In 14 patients, treated for recurrent rectal and cervical cancer, flexible catheters were sutured intra-operatively to the tumour bed in areas with compromised surgical margin. Both non-optimised, geometrically and graphically optimised CT -based dose plans were made. The overdose index (OI), homogeneity index (HI), conformal index (COIN), minimum target dose, and high dose volumes were evaluated. The dependence of OI, HI, and COIN on target volume and implant regularity was evaluated. In addition, 12 theoretical implant configurations were analyzed. Geometrical and graphical optimisation improved the dose plans significantly with graphical optimisation being superior. Graphically optimised dose plans showed a significant decrease of 18%+/-9% in high dose volume (p<0.001). HI, COIN, and OI were significantly improved from 0.50+/-0.05 to 0.60+/-0.05, from 0.65+/-0.04 to 0.71+/-0.04, and from 0.19+/-0.03 to 0.15+/-0.03, respectively (p<0.001 for all). Moreover, minimum target dose increased significantly from 71%+/-5% to 80%+/-5% (p<0.001). The improvement in OI and HI obtained by optimisation depended on the regularity of the implant, such that the benefit of optimisation was larger for irregular implants. OI and HI correlated strongly with target volume limiting the usability of these parameters for comparison of dose plans between patients. Dwell time optimisation significantly improved the dose distribution regarding homogeneity, conformity, minimum target dose, and size of high dose volumes. Graphical optimisation is fast, reproducible and superior to geometric optimisation.

  13. Surgical resection and permanent iodine-125 brachytherapy for brain metastases.

    Science.gov (United States)

    Huang, Kim; Sneed, Penny K; Kunwar, Sandeep; Kragten, Annemarie; Larson, David A; Berger, Mitchel S; Chan, Albert; Pouliot, Jean; McDermott, Michael W

    2009-01-01

    To evaluate the efficacy and toxicity of surgical resection and permanent iodine-125 brachytherapy without adjuvant whole brain radiation therapy (WBRT) for brain metastases. Forty patients were treated with permanent iodine-125 brachytherapy at the time of resection of brain metastases from 1997 to 2003. Actuarial freedom from progression (FFP) and survival were measured from the date of surgery and estimated using the Kaplan-Meier method, with censoring at last imaging for FFP endpoints. The median survival was 11.3 months overall, 12.0 months in 19 patients with newly diagnosed brain metastases and 7.3 months in 21 patients with recurrent brain metastases. Twenty-two patients (55%) remained free of progression of brain metastases, three failed at the resection cavity (including one with leptomeningeal dissemination), two failed with leptomeningeal spread only, and 13 failed elsewhere in the brain including two who also had leptomeningeal disease. The 1-year resection cavity FFP probabilities were 92%, 86% and 88%; and brain FFP probabilities were 29%, 43% and 37% for the newly diagnosed, recurrent and all patients, respectively. Symptomatic necrosis developed 7.4-40.0 months (median, 19.5 months) after brachytherapy in 9 patients (23%), confirmed by resection in 6 patients. Excellent local control was achieved using permanent iodine-125 brachytherapy for brain metastasis resection cavities, although there is a high risk of radiation necrosis over time. These data support consideration of permanent brachytherapy without adjuvant WBRT as a treatment option in patients with symptomatic or large newly diagnosed or recurrent brain metastases.

  14. All fiber-optic ultra-sensitive temperature sensor using few-layer MoS2 coated D-shaped fiber

    Science.gov (United States)

    Mohanraj, J.; Velmurugan, V.; Sathiyan, S.; Sivabalan, S.

    2018-01-01

    We experimentally demonstrate a novel all fiber-optic temperature sensor using Molybdenum disulfide (MoS2) nanosheets coated D-shaped fiber (DSF). The DSF exhibits a strong evanescent field interaction with the MoS2 nanosheets which in turn has good optical absorption that results in very high sensitivity. In addition, a few layer MoS2 exhibit high thermal conductivity and therefore highly suitable for temperature sensing. The proposed all fiber temperature sensor was investigated in the temperature range of 26 °C - 83 °C and achieved a maximum optical output power variation of 7 dB. Further, the experimental results show an ultrahigh sensitivity of 0.1211 dB/∘C, a linear correlation coefficient of 99.6 % and a better precision of 0.04 °C. Therefore, the proposed fiber-optic sensor is capable of measuring dynamic temperatures in a harsh environment.

  15. High-precision real-time 3D shape measurement using a bi-frequency scheme and multi-view system.

    Science.gov (United States)

    Tao, Tianyang; Chen, Qian; Feng, Shijie; Hu, Yan; Da, Jian; Zuo, Chao

    2017-05-01

    High-speed and high-precision 3D shape measurement plays a central role in diverse applications such as automatic online inspection, robotics control, and human-computer interaction. Conventional multi-frame phase-shifting-based fringe projection profilometry techniques face inherent trade-offs between the speed and measurement precision, which are fundamentally limited by the fringe density and extra pattern projections used for de-ambiguity of fringe orders. Increasing the frequency of the projection fringes can obviously improve the measurement precision; however, it creates difficulties in the subsequent phase unwrapping. For this reason, to date, the frequency of the fringes in typical real-time 3D shape measurement techniques is generally less than 30 to guarantee a reasonable reliability of phase unwrapping. To overcome this limitation, a bi-frequency phase-shifting technique based on a multi-view fringe projection system is proposed, which significantly enhances the measurement precision without compromising the measurement speed. Based on the geometric constraints in a multi-view system, the unwrapped phase of the low-frequency (10-period) fringes can be obtained directly, which serves as a reference to unwrap the high-frequency phase map with a total number of periods of up to 160. Besides, the proposed scheme with 10-period and 160-period fringes is suitable for slightly defocusing projection, allowing a higher projection rate and measurement speed. Experiments on both static and dynamic scenes are performed, verifying that our method can achieve high-speed and high-precision 3D measurement at 300 frames per second with a precision of about 50 μm.

  16. Use of ultrasound in image-guided high-dose-rate brachytherapy: enumerations and arguments

    OpenAIRE

    Susovan Banerjee; Tejinder Kataria; Deepak Gupta; Shikha Goyal; Shyam Singh Bisht; Trinanjan Basu; Ashu Abhishek

    2017-01-01

    Inherently, brachytherapy is the most conformal radiotherapeutic technique. As an aid to brachytherapy, ultrasonography (USG) serves as a portable, inexpensive, and simple to use method allowing for accurate, reproducible, and adaptive treatments. Some newer brachytherapy planning systems have incorporated USG as the sole imaging modality. Ultrasonography has been successfully used to place applicator and dose planning for prostate, cervix, and anal canal cancers. It can guide placement of br...

  17. TU-AB-BRC-08: Egs-brachy, a Fast and Versatile Monte Carlo Code for Brachytherapy Applications

    Energy Technology Data Exchange (ETDEWEB)

    Chamberland, M; Taylor, R; Rogers, D; Thomson, R [Carleton University, Ottawa, ON (Canada)

    2016-06-15

    Purpose: To introduce egs-brachy, a new, fast, and versatile Monte Carlo code for brachytherapy applications. Methods: egs-brachy is an EGSnrc user-code based on the EGSnrc C++ class library (egs++). Complex phantom, applicator, and source model geometries are built using the egs++ geometry module. egs-brachy uses a tracklength estimator to score collision kerma in voxels. Interaction, spectrum, energy fluence, and phase space scoring are also implemented. Phase space sources and particle recycling may be used to improve simulation efficiency. HDR treatments (e.g. stepping source through dwell positions) can be simulated. Standard brachytherapy seeds, as well as electron and miniature x-ray tube sources are fully modelled. Variance reduction techniques for electron source simulations are implemented (Bremsstrahlung cross section enhancement, uniform Bremsstrahlung splitting, and Russian Roulette). TG-43 parameters of seeds are computed and compared to published values. Example simulations of various treatments are carried out on a single 2.5 GHz Intel Xeon E5-2680 v3 processor core. Results: TG-43 parameters calculated with egs-brachy show excellent agreement with published values. Using a phase space source, 2% average statistical uncertainty in the PTV ((2mm){sup 3} voxels) can be achieved in 10 s for 100 {sup 125}I or {sup 103}Pd seeds in a 36.2 cm{sup 3} prostate PTV, 31 s for 64 {sup 103}Pd seeds in a 64 cm{sup 3} breast PTV, and 56 s for a miniature x-ray tube in a 27 cm{sup 3} breast PTV. Comparable uncertainty is reached in 12 s in a (1 mm){sup 3} water voxel 5 mm away from a COMS 16mm eye plaque with 13 {sup 103}Pd seeds. Conclusion: The accuracy of egs-brachy has been demonstrated through benchmarking calculations. Calculation times are sufficiently fast to allow full MC simulations for routine treatment planning for diverse brachytherapy treatments (LDR, HDR, miniature x-ray tube). egs-brachy will be available as free and open-source software to the

  18. Advantages of high-dose rate (HDR) brachytherapy in treatment of prostate cancer

    Science.gov (United States)

    Molokov, A. A.; Vanina, E. A.; Tseluyko, S. S.

    2017-09-01

    One of the modern methods of preserving organs radiation treatment is brachytherapy. This article analyzes the results of prostate brachytherapy. These studies of the advantages of high dose brachytherapy lead to the conclusion that this method of radiation treatment for prostate cancer has a favorable advantage in comparison with remote sensing methods, and is competitive, preserving organs in comparison to surgical methods of treatment. The use of the method of polyfocal transperineal biopsy during the brachytherapy session provides information on the volumetric spread of prostate cancer and adjust the dosimetry plan taking into account the obtained data.

  19. dose in cervical cancer intracavitary brachytherapy

    Directory of Open Access Journals (Sweden)

    Zahra Siavashpour

    2016-04-01

    Full Text Available Purpose: To analyze the optimum organ filling point for organs at risk (OARs dose in cervical cancer high-dose-rate (HDR brachytherapy. Material and methods : In a retrospective study, 32 locally advanced cervical cancer patients (97 insertions who were treated with 3D conformal external beam radiation therapy (EBRT and concurrent chemotherapy during 2010-2013 were included. Rotterdam HDR tandem-ovoid applicators were used and computed tomography (CT scanning was performed after each insertion. The OARs delineation and GEC-ESTRO-based clinical target volumes (CTVs contouring was followed by 3D forward planning. Then, dose volume histogram (DVH parameters of organs were recorded and patients were classified based on their OARs volumes, as well as their inserted tandem length. Results : The absorbed dose to point A ranged between 6.5-7.5 Gy. D 0.1cm ³ and D 2cm ³ of the bladder significantly increased with the bladder volume enlargement (p value < 0.05. By increasing the bladder volume up to about 140 cm3, the rectum dose was also increased. For the cases with bladder volumes higher than 140 cm3, the rectum dose decreased. For bladder volumes lower than 75 cm3, the sigmoid dose decreased; however, for bladder volumes higher than 75 cm3, the sigmoid dose increased. The D 2cm ³ of the bladder and rectum were higher for longer tandems than for shorter ones, respectively. The divergence of the obtained results for different tandem lengths became wider by the extension of the bladder volume. The rectum and sigmoid volume had a direct impact on increasing their D 0.1cm ³ and D 2cm ³, as well as decreasing their D 10 , D 30 , and D 50 . Conclusions : There is a relationship between the volumes of OARs and their received doses. Selecting a bladder with a volume of about 70 cm3 or less proved to be better with regards to the dose to the bladder, rectum, and sigmoid.

  20. Breast Diseases

    Science.gov (United States)

    Most women experience breast changes at some time. Your age, hormone levels, and medicines you take may cause lumps, bumps, and discharges (fluids that are not breast milk). If you have a breast lump, pain, ...

  1. 10 CFR 35.2067 - Records of leaks tests and inventory of sealed sources and brachytherapy sources.

    Science.gov (United States)

    2010-01-01

    ... brachytherapy sources. 35.2067 Section 35.2067 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2067 Records of leaks tests and inventory of sealed sources and brachytherapy sources... of the semi-annual physical inventory of sealed sources and brachytherapy sources required by § 35.67...

  2. Parallelized patient-specific quality assurance for high-dose-rate image-guided brachytherapy in an integrated computed tomography-on-rails brachytherapy suite.

    Science.gov (United States)

    Kim, Taeho; Showalter, Timothy N; Watkins, W Tyler; Trifiletti, Daniel M; Libby, Bruce

    2015-01-01

    To describe a parallelized patient-specific quality assurance (QA) program designed to ensure safety and quality in image-guided high-dose-rate brachytherapy in an integrated computed tomography (CT)-on-rails brachytherapy suite. A patient-specific QA program has been modified for the image-guided brachytherapy (IGBT) program in an integrated CT-on-rails brachytherapy suite. In the modification of the QA procedures of Task Group-59, the additional patient-specific QA procedures are included to improve rapid IGBT workflow with applicator placement, imaging, planning, treatment, and applicator removal taking place in one room. The IGBT workflow is partitioned into two groups of tasks that can be performed in parallel by two or more staff members. One of the unique components of our implemented workflow is that groups work together to perform QA steps in parallel and in series during treatment planning and contouring. Coordinating efforts in this systematic way enable rapid and safe brachytherapy treatment while incorporating 3-dimensional anatomic variations between treatment days. Implementation of these patient-specific QA procedures in an integrated CT-on-rails brachytherapy suite ensures confidence that a rapid workflow IGBT program can be implemented without sacrificing patient safety or quality and deliver highly-conformal dose to target volumes. These patient-specific QA components may be adapted to other IGBT environments that seek to provide rapid workflow while ensuring quality. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

    Han, Kathy, E-mail: Kathy.Han@rmp.uhn.on.ca [Radiation Medicine Program, Princess Margaret Hospital, University Health Network, Toronto, Ontario (Canada); Milosevic, Michael; Fyles, Anthony [Radiation Medicine Program, Princess Margaret Hospital, University Health Network, Toronto, Ontario (Canada); Pintilie, Melania [Department of Biostatistics, Princess Margaret Hospital, Toronto, Ontario (Canada); Viswanathan, Akila N. [Department of Radiation Oncology, Dana-Farber Cancer Institute/Brigham and Women' s Hospital, Boston, Massachusetts (United States)

    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.

  4. Salvage high-dose-rate brachytherapy for isolated vaginal recurrence of endometrial cancer.

    Science.gov (United States)

    Baek, Sungjae; Isohashi, Fumiaki; Yamaguchi, Hiroko; Mabuchi, Seiji; Yoshida, Ken; Kotsuma, Tadayuki; Yamazaki, Hideya; Tanaka, Eiichi; Sumida, Iori; Tamari, Keisuke; Otani, Keisuke; Seo, Yuji; Suzuki, Osamu; Yoshioka, Yasuo; Kimura, Tadashi; Ogawa, Kazuhiko

    We have retrospectively analyzed the outcomes of high-dose-rate (HDR) brachytherapy as a salvage therapy for vaginal recurrence of endometrial cancer. From 1997 to 2012, salvage HDR brachytherapy was performed in 43 patients. The median age was 64 years (range, 41-88 years). HDR brachytherapy was performed by interstitial brachytherapy in 34 patients (79%) and by intracavity brachytherapy in nine patients (21%). Seventeen (40%) of the 43 patients were treated with external beam radiotherapy. The median followup period was 58 months (range, 6-179 months). The 5-year overall survival (OS), progression-free survival (PFS), and local control rates (LC) were 84%, 52%, and 78%, respectively. Patients who received brachytherapy with external beam radiotherapy experienced no nodal recurrence (0 of 17 patients), whereas 23% of the patients (6 of 26 patients) who received brachytherapy alone experienced nodal recurrence (p = 0.047). The pathologic grade at the time of initial surgery (G1-2 vs. G3) was found to be a significant prognostic factor for both OS and PFS. The respective 5-year OS was 96% vs. 40% (p brachytherapy vs. intracavity brachytherapy) were significant prognostic factors for LC. The respective 5-year LC was 74% vs. 100% (p = 0.020) and 85% vs. 56% (p = 0.035). HDR brachytherapy is effective and feasible in patients with isolated vaginal recurrence of endometrial cancer. Pathologic grade, age, and modality were significant prognostic factors. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  5. Accelerated partial breast irradiation following breast-conservative surgery. A review; Irradiation partielle du sein apres chirurgie conservatrice revue de la litterature

    Energy Technology Data Exchange (ETDEWEB)

    Calais, G. [Hopital Bretonneau, Clinique d' Oncologie et Radiotherapie, 37 - Tours (France)

    2003-11-01

    After breast-conservative surgery, radiation therapy delivered to the whole breast to 50 Gy with an additional boost of 10 to 16 Gy is the standard of care. Based upon data showing that the vast majority of the recurrences occur within and surrounding the original tumor site and in order to reduce the morbidity of whole breast radiotherapy and to give the treatment in a shorter time, partial breast irradiation has been developed by several institutions. Partial breast radiotherapy is given by intraoperative radiotherapy (photons or electrons), or brachytherapy (low dose rate or high dose rate) or external radiotherapy using 3D conformal radiation therapy. This is a review of the literature data on this topic. (author)

  6. A statistical shape modelling framework to extract 3D shape biomarkers from medical imaging data: assessing arch morphology of repaired coarctation of the aorta.

    Science.gov (United States)

    Bruse, Jan L; McLeod, Kristin; Biglino, Giovanni; Ntsinjana, Hopewell N; Capelli, Claudio; Hsia, Tain-Yen; Sermesant, Maxime; Pennec, Xavier; Taylor, Andrew M; Schievano, Silvia

    2016-05-31

    Medical image analysis in clinical practice is commonly carried out on 2D image data, without fully exploiting the detailed 3D anatomical information that is provided by modern non-invasive medical imaging techniques. In this paper, a statistical shape analysis method is presented, which enables the extraction of 3D anatomical shape features from cardiovascular magnetic resonance (CMR) image data, with no need for manual landmarking. The method was applied to repaired aortic coarctation arches that present complex shapes, with the aim of capturing shape features as biomarkers of potential functional relevance. The method is presented from the user-perspective and is evaluated by comparing results with traditional morphometric measurements. Steps required to set up the statistical shape modelling analyses, from pre-processing of the CMR images to parameter setting and strategies to account for size differences and outliers, are described in detail. The anatomical mean shape of 20 aortic arches post-aortic coarctation repair (CoA) was computed based on surface models reconstructed from CMR data. By analysing transformations that deform the mean shape towards each of the individual patient's anatomy, shape patterns related to differences in body surface area (BSA) and ejection fraction (EF) were extracted. The resulting shape vectors, describing shape features in 3D, were compared with traditionally measured 2D and 3D morphometric parameters. The computed 3D mean shape was close to population mean values of geometric shape descriptors and visually integrated characteristic shape features associated with our population of CoA shapes. After removing size effects due to differences in body surface area (BSA) between patients, distinct 3D shape features of the aortic arch correlated significantly with EF (r = 0.521, p = .022) and were well in agreement with trends as shown by traditional shape descriptors. The suggested method has the potential to discover

  7. Dose volume analysis in brachytherapy and stereotactic radiosurgery

    CERN Document Server

    Tozer-Loft, S M

    2000-01-01

    compared with a range of figures of merit which express different aspects of the quality of each dose distributions. The results are analysed in an attempt to answer the question: What are the important features of the dose distribution (conformality, uniformity, etc) which show a definite relationship with the outcome of the treatment? Initial results show positively that, when Gamma Knife radiosurgery is used to treat acoustic neuroma, some measures of conformality seem to have a surprising, but significant association with outcome. A brief introduction to three branches of radiotherapy is given: interstitial brachytherapy, external beam megavoltage radiotherapy, and stereotactic radiosurgery. The current interest in issues around conformity, uniformity and optimisation is explained in the light of technical developments in these fields. A novel method of displaying dose-volume information, which mathematically suppresses the inverse-square law, as first suggested by L.L. Anderson for use in brachytherapy i...

  8. Brachytherapy optimal planning with application to intravascular radiation therapy.

    Science.gov (United States)

    Sadegh, P; Mourtada, F A; Taylor, R H; Anderson, J H

    1999-09-01

    We have been studying brachytherapy planning with the objective of minimizing the maximum deviation of the delivered dose from prescribed dose bounds for treatment volumes. A general framework for optimal treatment planning is presented and the minmax optimization is formulated as a linear program. Dose rate calculations are based on the dosimetry formulation of the American Association of Physicists in Medicine, Task Group 43. We apply the technique to optimal planning for intravascular brachytherapy of intimal hyperplasia using ultrasound data and 192Ir seeds. The planning includes determination of an optimal dwell-time sequence for a train of seeds that deliver radiation while stepping through the vessel lesion. The results illustrate the advantage of this strategy over the common approach of delivering radiation by positioning a single train of seeds along the whole lesion.

  9. Iodine-125 brachytherapy for brain tumours - a review

    Science.gov (United States)

    2012-01-01

    Iodine-125 brachytherapy has been applied to brain tumours since 1979. Even though the physical and biological characteristics make these implants particularly attractive for minimal invasive treatment, the place for stereotactic brachytherapy is still poorly defined. An extensive review of the literature has been performed, especially concerning indications, results and complications. Iodine-125 seeds have been implanted in astrocytomas I-III, glioblastomas, metastases and several other tumour entities. Outcome data given in the literature are summarized. Complications are rare in carefully selected patients. All in all, for highly selected patients with newly diagnosed or recurrent primary or metastatic tumours, this method provides encouraging survival rates with relatively low complication rates and a good quality of life. PMID:22394548

  10. 3T MR-Guided Brachytherapy for Gynecologic Malignancies

    CERN Document Server

    Kapur, Tina; Damato, Antonio; Schmidt, Ehud J; Viswanathan, Akila N; 10.1016/j.mri.2012.06.003

    2013-01-01

    Gynecologic malignancies are a leading cause of death in women worldwide. Standard treatment for many primary and recurrent gynecologic cancer cases includes a combination of external beam radiation, followed by brachytherapy. Magnetic Resonance Imaging (MRI) is benefitial in diagnostic evaluation, in mapping the tumor location to tailor radiation dose, and in monitoring the tumor response to treatment. Initial studies of MR-guidance in gynecologic brachtherapy demonstrate the ability to optimize tumor coverage and reduce radiation dose to normal tissues, resulting in improved outcomes for patients. In this article we describe a methodology to aid applicator placement and treatment planning for 3 Tesla (3T) MR-guided brachytherapy that was developed specifically for gynecologic cancers. This has been used in 18 cases to date in the Advanced Multimodality Image Guided Operating suite at Brigham and Women's Hospital. It is comprised of state of the art methods for MR imaging, image analysis, and treatment plann...

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Abraam S. Soliman

    2016-08-01

    Full Text Available 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.

  13. Which modality for prostate brachytherapy; Quelle modalite de curietherapie prostatique?

    Energy Technology Data Exchange (ETDEWEB)

    Bossi, A. [Departement de radiotherapie, institut Gustave-Roussy, 94 - Villejuif (France)

    2010-10-15

    Brachytherapy techniques by permanent implant of radioactive sources or by temporary high-dose-rate (HDR) fractions are nowadays extensively used for the treatment of prostatic carcinoma. Long-term results (at 20 years) concerning large amount of patients have been published by major centers confirming both in terms of efficacy and toxicities that permanent implant of radioactive iodine-125 seeds yields at least the same good results of surgery and of external beam irradiation when proposed to patients affected by low-risk disease. For intermediate to high-risk tumors, HDR temporary implants are proposed as a boost for dose escalation. For both techniques, several topics still need to be clarified dealing with a recent enlargement of indications (HDR alone for low-risk, iodine-125 seeds boost for intermediate-high-risk cancers), or with technical aspects (loose seeds versus linked ones, number of fractions and dose for HDR protocols), while dosimetric issues have only recently been addressed by cooperatives groups. Last but not least, there is a real need to address and clearly characterize the correct definition of biochemical disease control both for iodine permanent implant and for HDR implant. New challenges are facing the prostate-brachytherapy community in the near future: local relapse after external beam radiotherapy are currently managed by several salvage treatments (prostatectomy, cryo, high intensity focused ultrasounds [HIFU]) but the role of reirradiation by brachytherapy is also actively investigated. Focal therapy has gained considerable interest in the last 5 years aiming at treating only the area of cancer foci inside the prostate and preserving nearby healthy tissues. Encouraging results have been obtained with the so-called 'minimally invasive' approaches and both permanent seed implantation and HDR brachytherapy techniques may be worthwhile testing in this setting because of their capability of exactly sculpting the dose inside the

  14. Brachytherapy in Lip Carcinoma: Long-Term Results

    Energy Technology Data Exchange (ETDEWEB)

    Guibert, Mireille, E-mail: mireilleguib@voila.fr [Department of Head and Neck Surgery, Larrey Hospital, Toulouse (France); David, Isabelle [Department of Radiation Oncology, Claudius Regaud Institut, Toulouse (France); Vergez, Sebastien [Department of Head and Neck Surgery, Larrey Hospital, Toulouse (France); Rives, Michel [Department of Radiation Oncology, Claudius Regaud Institut, Toulouse (France); Filleron, Thomas [Department of Epidemiology, Claudius Regaud Institut, Toulouse (France); Bonnet, Jacques; Delannes, Martine [Department of Radiation Oncology, Claudius Regaud Institut, Toulouse (France)

    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.

  15. Photon energy-fluence correction factor in low energy brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Antunes, Paula C.G.; Yoriyaz, Hélio [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Vijande, Javier; Giménez-Alventosa, Vicent; Ballester, Facundo, E-mail: pacrisguian@gmail.com [Department of Atomic, Molecular, and Nuclear Physics and Instituto de Física Corpuscular (UV-CSIC), University of Valencia (Spain)

    2017-07-01

    The AAPM TG-43 brachytherapy dosimetry formalism has become a standard for brachytherapy dosimetry worldwide; it implicitly assumes that charged-particle equilibrium (CPE) exists for the determination of absorbed dose to water at different locations. At the time of relating dose to tissue and dose to water, or vice versa, it is usually assumed that the photon fluence in water and in tissues are practically identical, so that the absorbed dose in the two media can be related by their ratio of mass energy-absorption coefficients. The purpose of this work is to study the influence of photon energy-fluence in different media and to evaluate a proposal for energy-fluence correction factors for the conversion between dose-to-tissue (D{sub tis}) and dose-to-water (D{sub w}). State-of-the art Monte Carlo (MC) calculations are used to score photon fluence differential in energy in water and in various human tissues (muscle, adipose and bone) in two different codes, MCNP and PENELOPE, which in all cases include a realistic modeling of the {sup 125}I low-energy brachytherapy seed in order to benchmark the formalism proposed. A correction is introduced that is based on the ratio of the water-to-tissue photon energy-fluences using the large-cavity theory. In this work, an efficient way to correlate absorbed dose to water and absorbed dose to tissue in brachytherapy calculations at clinically relevant distances for low-energy photon emitting seed is proposed. The energy-fluence based corrections given in this work are able to correlate absorbed dose to tissue and absorbed dose to water with an accuracy better than 0.5% in the most critical cases. (author)

  16. Study of two different radioactive sources for prostate brachytherapy treatment

    Energy Technology Data Exchange (ETDEWEB)

    Pereira Neves, Lucio; Perini, Ana Paula [Instituto de Fisica, Universidade Federal de Uberlandia, Caixa Postal 593, 38400-902, Uberlandia, MG (Brazil); Souza Santos, William de; Caldas, Linda V.E. [Instituto de Pesquisas Energeticas e Nucleares, Comissao Nacional de Energia Nuclear, IPENCNEN/SP, Av. Prof. Lineu Prestes, 2242, Cidade Universitaria, 05508-000 Sao Paulo, SP (Brazil); Belinato, Walmir [Departamento de Ensino, Instituto Federal de Educacao, Ciencia e Tecnologia da Bahia, Campus Vitoria da Conquista, Zabele, Av. Amazonas 3150, 45030-220 Vitoria da Conquista, BA (Brazil)

    2015-07-01

    In this study we evaluated two radioactive sources for brachytherapy treatments. Our main goal was to quantify the absorbed doses on organs and tissues of an adult male patient, submitted to a brachytherapy treatment with two radioactive sources. We evaluated a {sup 192}Ir and a {sup 125}I radioactive sources. The {sup 192}Ir radioactive source is a cylinder with 0.09 cm in diameter and 0.415 cm long. The {sup 125}I radioactive source is also a cylinder, with 0.08 cm in diameter and 0.45 cm long. To evaluate the absorbed dose distribution on the prostate, and other organs and tissues of an adult man, a male virtual anthropomorphic phantom MASH, coupled in the radiation transport code MCNPX 2.7.0, was employed.We simulated 75, 90 and 102 radioactive sources of {sup 125}I and one of {sup 192}Ir, inside the prostate, as normally used in these treatments, and each treatment was simulated separately. As this phantom was developed in a supine position, the displacement of the internal organs of the chest, compression of the lungs and reduction of the sagittal diameter were all taken into account. For the {sup 192}Ir, the higher doses values were obtained for the prostate and surrounding organs, as the colon, gonads and bladder. Considering the {sup 125}I sources, with photons with lower energies, the doses to organs that are far from the prostate were lower. All values for the dose rates are in agreement with those recommended for brachytherapy treatments. Besides that, the new seeds evaluated in this work present usefulness as a new tool in prostate brachytherapy treatments, and the methodology employed in this work may be applied for other radiation sources, or treatments. (authors)

  17. Ruby-based inorganic scintillation detectors for 192Ir brachytherapy

    Science.gov (United States)

    Kertzscher, Gustavo; Beddar, Sam

    2016-11-01

    We tested the potential of ruby inorganic scintillation detectors (ISDs) for use in brachytherapy and investigated various unwanted luminescence properties that may compromise their accuracy. The ISDs were composed of a ruby crystal coupled to a poly(methyl methacrylate) fiber-optic cable and a charge-coupled device camera. The ISD also included a long-pass filter that was sandwiched between the ruby crystal and the fiber-optic cable. The long-pass filter prevented the Cerenkov and fluorescence background light (stem signal) induced in the fiber-optic cable from striking the ruby crystal, which generates unwanted photoluminescence rather than the desired radioluminescence. The relative contributions of the radioluminescence signal and the stem signal were quantified by exposing the ruby detectors to a high-dose-rate brachytherapy source. The photoluminescence signal was quantified by irradiating the fiber-optic cable with the detector volume shielded. Other experiments addressed time-dependent luminescence properties and compared the ISDs to commonly used organic scintillator detectors (BCF-12, BCF-60). When the brachytherapy source dwelled 0.5 cm away from the fiber-optic cable, the unwanted photoluminescence was reduced from  >5% to  5% within 10 s from the onset of irradiation and after the source had retracted. The ruby-based ISDs generated signals of up to 20 times that of BCF-12-based detectors. The study presents solutions to unwanted luminescence properties of ruby-based ISDs for high-dose-rate brachytherapy. An optic filter should be sandwiched between the ruby crystal and the fiber-optic cable to suppress the photoluminescence. Furthermore, we recommend avoiding ruby crystals that exhibit significant time-dependent luminescence.

  18. HDR brachytherapy for superficial non-melanoma skin cancers.

    Science.gov (United States)

    Gauden, Ruth; Pracy, Martin; Avery, Anne-Marie; Hodgetts, Ian; Gauden, Stan

    2013-04-01

    Our initial experience using recommended high dose per fraction skin brachytherapy (BT) treatment schedules, resulted in poor cosmesis. This study aimed to assess in a prospective group of patients the use of Leipzig surface applicators for High Dose Rate (HDR) brachytherapy, for the treatment of small non-melanoma skin cancers (NMSC) using a protracted treatment schedule. Treatment was delivered by HDR brachytherapy with Leipzig applicators. 36 Gy, prescribed to between 3 to 4 mm, was given in daily 3 Gy fractions. Acute skin toxicity was evaluated weekly during irradiation using the Radiation Therapy Oncology Group criteria. Local response, late skin effects and cosmetic results were monitored at periodic intervals after treatment completion. From March 2002, 200 patients with 236 lesions were treated. Median follow-up was 66 months (range 25-121 months). A total of 162 lesions were macroscopic, while in 74 cases, BT was given after resection because of positive microscopic margins. There were 121 lesions that were basal cell carcinomas, and 115 were squamous cell carcinomas. Lesions were located on the head and neck (198), the extremities (26) and trunk (12). Local control was 232/236 (98%). Four patients required further surgery to treat recurrence. Grade 1 acute skin toxicity was detected in 168 treated lesions (71%) and grade 2 in 81 (34%). Cosmesis was good or excellent in 208 cases (88%). Late skin hypopigmentation changes were observed in 13 cases (5.5%). Delivering 36 Gy over 2 weeks to superficial NMSC using HDR brachytherapy is well tolerated and provides a high local control rate without significant toxicity. © 2012 The Authors. Journal of Medical Imaging and Radiation Oncology © 2012 The Royal Australian and New Zealand College of Radiologists.

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

    Energy Technology Data Exchange (ETDEWEB)

    Taira, Al V. [Western Radiation Oncology, Mountain View, CA (United States); Merrick, Gregory S., E-mail: gmerrick@urologicresearchinstitute.org [Schiffler Cancer Center, Wheeling Jesuit University, Wheeling, WV (United States); Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan H.; Allen, Zachariah A. [Schiffler Cancer Center, Wheeling Jesuit University, Wheeling, WV (United States); Wallner, Kent E. [Puget Sound Healthcare Corporation Group Health Cooperative, University of Washington, Seattle, WA (United States)

    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

  20. Cost effectiveness of new breast cancer radiotherapy technologies in diverse populations.

    Science.gov (United States)

    Gold, Heather Taffet; Hayes, Mary Katherine

    2012-11-01

    Accelerated partial breast radiotherapy (RT) strategies (3-D conformal external-beam RT (3-D CRT) and brachytherapy with balloon catheter) reduce time and transportation burdens of whole breast RT for breast cancer. Long-term clinical trial evidence is unavailable for accelerated modalities, but uncertainty might be acceptable for patients likely to receive suboptimal whole breast RT. The objective of this study is to assess the cost effectiveness of accelerated partial breast RT compared to on-time and delayed whole breast RT. The design used in this study is decision analytic Markov model. The data sources are published literature; and national/federal sources. The target population of this study is a hypothetical cohort of 60 years old women previously treated with breast-conserving surgery for node-negative, estrogen receptor-positive breast cancer with tumors costs (2008 US$), quality-adjusted life years (QALYs), and incremental cost-effectiveness ratios. The base-case results were: 3-D CRT was the preferred strategy, costing on average $10,800 and yielding 11.21 QALYs. On-time whole breast RT costs $368,000/QALY compared to 3-D CRT, above the $100,000/QALY WTP threshold. 3-D CRT was also preferred over delayed whole breast RT. Brachytherapy was never preferred. Sensitivity analysis indicated that the results were sensitive to the rate of recurrence outside the initial tumor quadrant ("elsewhere failure") in one-way analysis. Probabilistic sensitivity analysis indicated that results were sensitive to parameter uncertainty, and that the elsewhere-failure rate and treatment preferences may drive results. The limitation of this study is that efficacy estimates are derived from studies that may not fully represent the population modeled. As a conclusion, 3-D CRT was preferred to whole breast RT and for women likely to delay RT, indicating that 3-D CRT could be targeted more efficiently before randomized trial evidence.

  1. Postoperative high-dose-rate brachytherapy in the prevention of keloids

    NARCIS (Netherlands)

    Veen, Ronald E.; Kal, Henk B.

    2007-01-01

    Background: The aim of this study is to show the efficiency of keloidectomy and postoperative interstitial high-dose-rate (HDR) brachytherapy in the prevention of keloids. Methods and Materials: Between 1998 and 2004, 35 patients with 54 keloids were treated postoperatively with HDR brachytherapy.

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

    Energy Technology Data Exchange (ETDEWEB)

    Tortorelli, J.P.; Simion, G.P.; Kozlowski, S.D. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    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.

  3. Salvage high-dose-rate brachytherapy for esophageal cancer in previously irradiated patients: A retrospective analysis.

    Science.gov (United States)

    Wong Hee Kam, Stéphanie; Rivera, Sofia; Hennequin, Christophe; Lourenço, Nelson; Chirica, Mircea; Munoz-Bongrand, Nicolas; Gornet, Jean-Marc; Quéro, Laurent

    2015-01-01

    To evaluate outcomes after exclusive salvage high-dose-rate (HDR) intraluminal esophageal brachytherapy given to previously irradiated patients with recurrent esophageal cancer. We reviewed medical records of 30 patients who were treated by salvage HDR brachytherapy for local esophageal cancer. Brachytherapy delivered four to six fractions of 5-7 Gy at 5 mm from the applicator surface and 20 mm above and below the macroscopic tumor volume. Eighty percentage of patients received treatment as initially planned. Complete response rate, evaluated 1 month after brachytherapy by endoscopy and biopsy, was 53%. Squamous histology and complete endoscopic tumor response at 1 month were significantly associated with better local tumor control. Median local progression-free survival was 9.8 months. Overall survival was 31.5% and 17.5% at 1 and 2 years, respectively. On univariate analysis, preserved performance status and limited weight loss (brachytherapy were associated with better overall survival. Severe toxicity (Grade ≥3) occurred in 7 patients (23%). Although esophageal cancer in previously irradiated patients is associated with poor outcomes, HDR brachytherapy may be a valuable salvage treatment for inoperable patients with locally limited esophageal cancer, particularly in the subset of patients with preserved performance status and limited weight loss (≤10%) before salvage brachytherapy. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  4. Differences in outcome for cervical cancer patients treated with or without brachytherapy.

    Science.gov (United States)

    Karlsson, Johannes; Dreifaldt, Ann-Charlotte; Mordhorst, Louise Bohr; Sorbe, Bengt

    To compare the clinical outcome of cervical cancer patients treated with primary radiotherapy with and without the addition of brachytherapy. In all, 220 patients with cervical cancer stage I-IV treated between 1993 and 2009 were included. Three or five 6.0 Gy fractions of brachytherapy were given in addition to the external beam radiotherapy to 134 patients, whereas 86 patients received external beam radiotherapy alone (EBRTA). In the EBRTA group, the patients received external boost instead of brachytherapy with a total dose to the tumor of 64-72 Gy. The 5-year overall survival and cancer-specific survival rates of the complete series were 42.5% and 55.5%, respectively. The rates of primary complete remission, 5-year cancer-specific survival, and recurrence were 92.5%, 68.5%, and 31.3% for the brachytherapy group vs. 73.3%, 35.4%, and 37.2% for the EBRTA group. The survival (all types) of the patients receiving brachytherapy was significantly (p brachytherapy group. Brachytherapy is important to achieve sufficient doses to the periphery and central part of the tumor and should always be considered in treatment of cervical carcinomas. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  5. The darker-is-deeper heuristic for the perception of 3D shape from shading: Is it perceptually or ecologically valid?

    Science.gov (United States)

    Todd, James T; Egan, Eric J L; Kallie, Christopher S

    2015-01-01

    The darker-is-deeper heuristic was originally proposed by Langer and Zucker (1994) for approximating 3D shape from shading under conditions of diffuse illumination that typically occur for outdoor scenes on a cloudy day, and it is based on the assumption that vignetting is the primary source of luminance variation under those conditions. It was later rejected as a model of human perception by Langer and Bülthoff (2000), because points in concavities that appear to be the deepest are most often located on local luminance maxima. Despite that result, this heuristic has continued to be described in the literature as a viable model of human perception (e.g., Chen & Tyler, 2015; Tyler, 1998), based entirely on the appearance of image intensity gratings, which have little or no connection to real 3D surfaces or patterns of illumination. In this article we will present a large number of examples to show what actually happens when surfaces are viewed under directional and diffuse illuminations. The results will highlight a number of well-known phenomena in addition to vignetting that can influence the pattern of shading on a surface under diffuse illumination, and they will also demonstrate that the darker-is-deeper heuristic is generally invalid for all types of illumination, except in unusual circumstances.

  6. Salvage brachytherapy for locally recurrent prostate cancer after external beam radiotherapy

    Directory of Open Access Journals (Sweden)

    Yasuhiro Yamada

    2015-01-01

    Full Text Available External beam radiotherapy (EBRT is a standard treatment for prostate cancer. Despite the development of novel radiotherapy techniques such as intensity-modulated conformal radiotherapy, the risk of local recurrence after EBRT has not been obviated. Various local treatment options (including salvage prostatectomy, brachytherapy, cryotherapy, and high-intensity focused ultrasound [HIFU] have been employed in cases of local recurrence after primary EBRT. Brachytherapy is the first-line treatment for low-risk and selected intermediate-risk prostate tumors. However, few studies have examined the use of brachytherapy to treat post-EBRT recurrent prostate cancer. The purpose of this paper is to analyze the current state of our knowledge about the effects of salvage brachytherapy in patients who develop locally recurrent prostate cancer after primary EBRT. This article also introduces our novel permanent brachytherapy salvage method.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  9. American Brachytherapy Society Task Group Report: Combination of brachytherapy and external beam radiation for high-risk prostate cancer.

    Science.gov (United States)

    Spratt, Daniel E; Soni, Payal D; McLaughlin, Patrick W; Merrick, Gregory S; Stock, Richard G; Blasko, John C; Zelefsky, Michael J

    To review outcomes for high-risk prostate cancer treated with combined modality radiation therapy (CMRT) utilizing external beam radiation therapy (EBRT) with a brachytherapy boost. The available literature for high-risk prostate cancer treated with combined modality radiation therapy was reviewed and summarized. At this time, the literature suggests that the majority of high-risk cancers are curable with multimodal treatment. Several large retrospective studies and three prospective randomized trials comparing CMRT to dose-escalated EBRT have demonstrated superior biochemical control with CMRT. Longer followup of the randomized trials will be required to determine if this will translate to a benefit in metastasis-free survival, disease-specific survival, and overall survival. Although greater toxicity has been associated with CMRT compared to EBRT, recent studies suggest that technological advances that allow better definition and sparing of critical adjacent structures as well as increasing experience with brachytherapy have improved implant quality and the toxicity profile of brachytherapy. The role of androgen deprivation therapy is well established in the external beam literature for high-risk disease, but there is controversy regarding the applicability of these data in the setting of dose escalation. At this time, there is not sufficient evidence for the omission of androgen deprivation therapy with dose escalation in this population. Comparisons with surgery remain limited by differences in patient selection, but the evidence would suggest better disease control with CMRT compared to surgery alone. Due to a series of technological advances, modern combination series have demonstrated unparalleled rates of disease control in the high-risk population. Given the evidence from recent randomized trials, combination therapy may become the standard of care for high-risk cancers. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All

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

    Energy Technology Data Exchange (ETDEWEB)

    Al-Qaisieh, Bashar [Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Mason, Josh, E-mail: joshua.mason@nhs.net [Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Bownes, Peter; Henry, Ann [Leeds Cancer Centre, Leeds Teaching Hospitals NHS Trust, Leeds (United Kingdom); Dickinson, Louise [Division of Surgery and Interventional Science, University College London, London (United Kingdom); Department of Radiology, Northwick Park Hospital, London North West NHS Trust, London (United Kingdom); Ahmed, Hashim U. [Division of Surgery and Interventional Science, University College London, London (United Kingdom); University College London Hospital, London (United Kingdom); Emberton, Mark [University College London Hospital, London (United Kingdom); Langley, Stephen [St Luke' s Cancer Centre, Guildford (United Kingdom)

    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

  11. Breast pain

    Science.gov (United States)

    ... the level of of hormones during menstruation or pregnancy often cause breast pain. Some swelling and tenderness just before your period is normal. Some women who have pain in one or both breasts may fear breast cancer . However, breast pain is not a common symptom ...

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

    Energy Technology Data Exchange (ETDEWEB)

    Craciunescu, O [Duke University Medical Center, Durham, NC (United States); Todor, D [Virginia Commonwealth University, Richmond, VA (United States); 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.

  13. Fast patient-specific Monte Carlo brachytherapy dose calculations via the correlated sampling variance reduction technique

    Energy Technology Data Exchange (ETDEWEB)

    Sampson, Andrew; Le Yi; Williamson, Jeffrey F. [Department of Radiation Oncology, Virginia Commonwealth University, Richmond, Virginia 23298 (United States)

    2012-02-15

    Purpose: To demonstrate potential of correlated sampling Monte Carlo (CMC) simulation to improve the calculation efficiency for permanent seed brachytherapy (PSB) implants without loss of accuracy. Methods: CMC was implemented within an in-house MC code family (PTRAN) and used to compute 3D dose distributions for two patient cases: a clinical PSB postimplant prostate CT imaging study and a simulated post lumpectomy breast PSB implant planned on a screening dedicated breast cone-beam CT patient exam. CMC tallies the dose difference, {Delta}D, between highly correlated histories in homogeneous and heterogeneous geometries. The heterogeneous geometry histories were derived from photon collisions sampled in a geometrically identical but purely homogeneous medium geometry, by altering their particle weights to correct for bias. The prostate case consisted of 78 Model-6711 {sup 125}I seeds. The breast case consisted of 87 Model-200 {sup 103}Pd seeds embedded around a simulated lumpectomy cavity. Systematic and random errors in CMC were unfolded using low-uncertainty uncorrelated MC (UMC) as the benchmark. CMC efficiency gains, relative to UMC, were computed for all voxels, and the mean was classified in regions that received minimum doses greater than 20%, 50%, and 90% of D{sub 90}, as well as for various anatomical regions. Results: Systematic errors in CMC relative to UMC were less than 0.6% for 99% of the voxels and 0.04% for 100% of the voxels for the prostate and breast cases, respectively. For a 1 x 1 x 1 mm{sup 3} dose grid, efficiency gains were realized in all structures with 38.1- and 59.8-fold average gains within the prostate and breast clinical target volumes (CTVs), respectively. Greater than 99% of the voxels within the prostate and breast CTVs experienced an efficiency gain. Additionally, it was shown that efficiency losses were confined to low dose regions while the largest gains were located where little difference exists between the homogeneous and

  14. In vitro experiments on PDR brachytherapy; In-Vitro-Untersuchungen zur PDR-Brachytherapie

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, P.; Frank, C. [Klinik fuer Radioonkologie, St. Marien-Krankenhaus, Siegen (Germany); Weber, K.J. [Abt. fuer Strahlentherapie, Radiologische Klinik, Heidelberg Univ. (Germany)

    1998-07-01

    Simulating the clinical situation in PDR brachytherapy, fractionation experiments were carried out in the dose rate gradient of afterloading sources. Different dose levels were produced with the same number of fractions in the same overall incubation time. The fractionation schedules which were to be compared with a CLDR reference curve were: 40x0.47 Gy, 20x0.94 Gy, 10x1.88 Gy, 5x3.76 Gy, 2x9.4 Gy given in a period of 20 h and 1x18.8 Gy as a `single dose` exposition. As measured by flow cytometry, the influence of the dose rate in the pulse on cell survival and on cell cycle distribution under superfractionation was examined on V79 cells. V79 spheroids as a model for a slowly growing tumor, reacted according to the radiobiological calculations, as a CLDR equivalancy was achieved with increasing fractionation. Rapidly growing V79 monolayer cells showed an inverse fractionation effect. A superfractionated irradiation with pulses of 0.94 Gy/h respectively 0.47 Gy/0.5 h was significantly more effective than the CLDR irradiation. This inverse fractionation effect in log-phase V79 cells could be attributed to the accumulation of cycling cells in the radiosensitive G2/M phase (G2 block) during protected exposure which was drastically more pronounced for the pulsed scheme. HeLa cells were rather insensitive to changes of fractionation. Superfractionation as well as hypofractionation yielded CLDR equivalent survival curves. (orig./MG) [Deutsch] In Anlehnung an die klinischen Verhaeltnisse der PDR-Brachytherapie wurden Fraktionierungsexperimente im Dosis-Leistungs-Gradienten von Afterloading-Quellen durchgefuehrt. Unterschiedliche Strahlendosen wurden mit der jeweils gleichen Anzahl von Fraktionen und in der jeweils gleichen `Gesamtinkubationszeit` erzeugt. Folgende Fraktionierungen wurden mit einer CLDR-Referenzkurve verglichen: 40x0,47 Gy, 20x0,94 Gy, 10x1,88 Gy, 5x3,76 Gy, 2x9,4 Gy in jeweils 20 Stunden und einmal 18,8 Gy als `Single-dose-`Exposition. Zusaetzlich wurden

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

    Directory of Open Access Journals (Sweden)

    Kasper ME

    2015-11-01

    Full Text Available Michael E Kasper,1,2 Ahmed A Chaudhary3 1Department of Radiation Oncology, Lynn Cancer Institute at Boca Raton Regional Hospital, Boca Raton, 2Charles E. Schmidt College of Medicine, Florida Atlantic University, FL, 3North Main Radiation Oncology, Warren Alpert School of Medicine, Brown University, RI, USA Abstract: 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. Keywords: electronic brachytherapy, superficial radiotherapy, skin surface brachytherapy, electron beam therapy, nonmelanoma skin cancer, basal cell carcinoma, squamous cell carcinoma

  16. (106)Ru plaque brachytherapy for uveal melanoma: factors associated with local tumor recurrence.

    Science.gov (United States)

    Barker, Christopher A; Francis, Jasmine H; Cohen, Gil'ad N; Marr, Brian P; Wolden, Suzanne L; McCormick, Beryl; Abramson, David H

    2014-01-01

    Plaque brachytherapy is a common form of treatment for uveal melanoma, and the Collaborative Ocular Melanoma Study (COMS) used (125)I. Recently, (106)Ru has been reintroduced for plaque brachytherapy in the United States. We reviewed our experience treating uveal melanoma with (106)Ru plaque brachytherapy using COMS planning techniques, hypothesizing that we would observe similar outcomes to those in the COMS. Medical records of patients undergoing (106)Ru plaque brachytherapy were reviewed retrospectively. Patient, tumor, and treatment characteristics were recorded. Outcomes including visual acuity, local tumor recurrence, salvage treatment, metastasis, and survival were recorded. Cox regression analyses were used to determine factors associated with local tumor recurrence and enucleation. Twenty-eight patients were studied. Median age was 60 years, and 50% were men. Median tumor base diameter and height were 9.4 and 2.6 mm, respectively. Ophthalmic complications were rare. Local tumor recurrence and enucleation occurred in 13 and 4 patients, respectively. Local tumor recurrence was associated with low visual acuity in the tumor-bearing eye, posterior tumors, small plaque size, and difference in plaque-tumor diameter of brachytherapy using COMS planning techniques, we found a greater than expected rate of local tumor recurrence. Planning (106)Ru plaque brachytherapy should be done carefully at centers that have previously used COMS protocols and (125)I. Copyright © 2014 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  17. Attenuation measurements show that the presence of a TachoSil surgical patch will not compromise target irradiation in intra-operative electron radiation therapy or high-dose-rate brachytherapy.

    Science.gov (United States)

    Sarmento, Sandra; Costa, Filipa; Pereira, Alexandre; Lencart, Joana; Dias, Anabela; Cunha, Luís; Sousa, Olga; Silva, José Pedro; Santos, Lúcio

    2015-01-09

    Surgery of locally advanced and/or recurrent rectal cancer can be complemented with intra-operative electron radiation therapy (IOERT) to deliver a single dose of radiation directly to the unresectable margins, while sparing nearby sensitive organs/structures. Haemorrhages may occur and can affect the dose distribution, leading to an incorrect target irradiation. The TachoSil (TS) surgical patch, when activated, creates a fibrin clot at the surgical site to achieve haemostasis. The aim of this work was to determine the effect of TS on the dose distribution, and ascertain whether it could be used in combination with IOERT. This characterization was extended to include high dose rate (HDR) intraoperative brachytherapy, which is sometimes used at other institutions instead of IOERT. CT images of the TS patch were acquired for initial characterization. Dosimetric measurements were performed in a water tank phantom, using a conventional LINAC with a hard-docking system of cylindrical applicators. Percentage Depth Dose (PDD) curves were obtained, and measurements made at the depth of dose maximum for the three clinically used electron energies (6, 9 and 12MeV), first without any attenuator and then with the activated patch of TS completely covering the tip of the IOERT applicator. For HDR brachytherapy, a measurement setup was improvised using a solid water phantom and a Farmer ionization chamber. Our measurements show that the attenuation of a TachoSil patch is negligible, both for high energy electron beams (6 to 12MeV), and for a HDR (192)Ir brachytherapy source. Our results cannot be extrapolated to lower beam energies such as 50 kVp X-rays, which are sometimes used for breast IORT. The TachoSil surgical patch can be used in IORT procedures using 6MeV electron energies or higher, or HDR (192)Ir brachytherapy.

  18. Interstitial brachytherapy for eyelid carcinoma. Outcome analysis in 60 patients

    Energy Technology Data Exchange (ETDEWEB)

    Krengli, M.; Deantonio, L. [University Hospital ' ' Maggiore della Carita' ' , Division of Radiotherapy, Novara (Italy); University of ' ' Piemonte Orientale' ' , Department of Translational Medicine, Novara (Italy); Masini, L.; Filomeno, A.; Gambaro, G. [University Hospital ' ' Maggiore della Carita' ' , Division of Radiotherapy, Novara (Italy); Comoli, A.M. [University Hospital Maggiore della Carita, Ophthalmology, Novara (Italy); Negri, E. [University Hospital Maggiore della Carita, Medical Physics, Novara (Italy)

    2014-03-15

    Eyelid cancer is a therapeutic challenge due to the cosmetic and functional implications of this anatomical region and the objectives of therapy are tumor control, functional and cosmetic outcome. The present study was performed to analyze local control, toxicity, functional and cosmetic results in patients with eyelid carcinoma treated by interstitial brachytherapy. In this study 60 patients with eyelid carcinoma were treated by interstitial brachytherapy using iridium ({sup 192}Ir) wires with a linear activity of 1.2-1.7 mCi/cm. The prescription dose was 51-70 Gy (mean 65 Gy, median 66 Gy). Of the 60 patients 51 (85.0 %) had received no prior treatment, 4 (6.7 %) had received previous surgery with positive or close margins and 5 (8.3 %) had suffered local recurrence after surgery. Of the tumors 52 (86.7 %) were basal cell carcinoma, 7 (11.7 %) squamous cell carcinoma and 1 (1.7 %) Merkel cell carcinoma. Clinical stage of the 51 previously untreated tumors was 38 T1N0, 12 T2N0 and 1 T3N0. Mean follow-up was 92 months (range 6-253 months). Local control was maintained in 96.7 % of patients. Late effects higher than grade 2 were observed in 3.0 % of cases. Functional and cosmetic outcomes were optimal in 68.4 % of patients. Interstitial brachytherapy for carcinoma of the eyelid can achieve local control, cosmetic and functional results comparable to those of surgery. (orig.) [German] Das Karzinom des Augenlids stellt aufgrund der funktionellen und kosmetischen Beeintraechtigungen dieser anatomischen Region eine therapeutische Herausforderung dar. Ziele der Therapie sind sowohl die Tumorkontrolle als auch ein gutes funktionelles und kosmetisches Ergebnis. Lokale Kontrolle, Toxizitaet sowie funktionelle und kosmetische Ergebnisse bei Patienten mit Karzinom des Augenlids, die mit interstitieller Brachytherapie behandelt wurden, sollten analysiert werden. Sechzig Patienten mit Karzinom des Augenlids wurden mit interstitieller Brachytherapie mit Iridium-192-Draehten

  19. Major causes of impractical brachytherapy in elderly patients with uterine cervical cancer.

    Science.gov (United States)

    Yanazume, Yumi; Yanazume, Shintaro; Iio, Kazuto; Yonekura, Ryuji; Kojima, Nobuko; Uchida, Natsuko; Koriyama, Chihaya; Douchi, Tsutomu

    2014-06-01

    Incomplete brachytherapy is a major risk factor for recurrence. However, high-dose-rate intracavitary brachytherapy has not been assessed adequately in elderly patients with invasive cervical cancer. The present study investigated the clinical importance of intracavitary brachytherapy and risk factors of incomplete intracavitary brachytherapy in elderly patients with cervical cancer. Subjects were 76 patients aged 70-89 years old with invasive cervical cancer. All subjects were recruited between January 1997 and September 2010, and were planning to receive external beam radiation therapy followed by high-dose-rate intracavitary brachytherapy. Survival rates and the incidence of complications were compared between the 70s and 80s age groups. Risk factors for recurrence in elderly patients were evaluated using multivariate analysis, and risk factors for impractical intracavitary brachytherapy were also estimated. No significant differences were observed in 3-year progression-free survival rates or the incidence of complications in the two age groups. Cox multivariate analysis showed that histology (non-squamous cell carcinoma), incomplete intracavitary brachytherapy, and lymph node swelling were significant prognostic factors for recurrence. Impractical application was the major reason for incomplete treatment. Multiple logistic regression analysis revealed that a previous history without vaginal births (P = 0.016) was an independent risk factor for the impractical application, independent of tumor diameter ≥ 4 cm (P = 0.007). Incomplete intracavitary brachytherapy decreased the survival rates of elderly patients. Larger tumors and patients without a history of vaginal births were the two major causes of impractical intracavitary brachytherapy, which may be fatal, especially in elderly patients with bulky tumors. © 2014 The Authors. Journal of Obstetrics and Gynaecology Research © 2014 Japan Society of Obstetrics and Gynecology.

  20. High brachytherapy doses can counteract hypoxia in cervical cancer—a modelling study

    Science.gov (United States)

    Lindblom, Emely; Dasu, Alexandru; Beskow, Catharina; Toma-Dasu, Iuliana

    2017-01-01

    Tumour hypoxia is a well-known adverse factor for the outcome of radiotherapy. For cervical tumours in particular, several studies indicate large variability in tumour oxygenation. However, clinical evidence shows that the management of cervical cancer including brachytherapy leads to high rate of success. It was the purpose of this study to investigate whether the success of brachytherapy for cervical cancer, seemingly regardless of oxygenation status, could be explained by the characteristics of the brachytherapy dose distributions. To this end, a previously used in silico model of tumour oxygenation and radiation response was further developed to simulate the treatment of cervical cancer employing a combination of external beam radiotherapy and intracavitary brachytherapy. Using a clinically-derived brachytherapy dose distribution and assuming a homogeneous dose delivered by external radiotherapy, cell survival was assessed on voxel level by taking into account the variation of sensitivity with oxygenation as well as the effects of repair, repopulation and reoxygenation during treatment. Various scenarios were considered for the conformity of the brachytherapy dose distribution to the hypoxic region in the target. By using the clinically-prescribed brachytherapy dose distribution and varying the total dose delivered with external beam radiotherapy in 25 fractions, the resulting values of the dose for 50% tumour control, D 50, were in agreement with clinically-observed values for high cure rates if fast reoxygenation was assumed. The D 50 was furthermore similar for the different degrees of conformity of the brachytherapy dose distribution to the tumour, regardless of whether the hypoxic fraction was 10%, 25%, or 40%. To achieve 50% control with external RT only, a total dose of more than 70 Gy in 25 fractions would be required for all cases considered. It can thus be concluded that the high doses delivered in brachytherapy can counteract the increased

  1. Intensity-based fluoroscopy and ultrasound registration for prostate brachytherapy

    Science.gov (United States)

    Aghaloo, Zahra Karim

    Prostate cancer continues to be the most commonly diagnosed cancer among men. Brachytherapy has emerged as one of the definitive treatment options for early stage prostate cancer which entails permanent implantation of radioactive seeds into the prostate to eradicate the cancer with ionizing radiation. Successful brachytherapy requires the ability to perform dosimetry -which requires seed localization- during the procedure but such function is not available today. If dosimetry could be performed intraoperatively, physicians could implant additional seeds into the under-dosed portions of the prostate while the patient is still on the operating table. This thesis addresses the brachytherapy seed localization problem with introducing intensity based registration between transrectal ultrasound (TRUS) that shows only the prostate and a 3D seed model drawn from fluoroscopy that shows only the implanted seeds. The TRUS images are first filtered and compounded, and then registered to the seed model by using mutual information. A training phantom was implanted with 48 seeds and imaged. Various ultrasound filtering techniques were analyzed. The effect of false positives and false negatives in ultrasound was investigated by randomly masking seeds from the fluoroscopy volume or adding seeds to that in random locations. Furthermore, the effect of sparse and dense ultrasound data was analyzed by running the registration for ultrasound data with different spacing. The registration error remained consistently below clinical threshold and capture range was significantly larger than the initial guess guaranteed by the clinical workflow. This fully automated method provided excellent registration accuracy and robustness in phantom studies and promises to demonstrate clinically adequate performance on human data.

  2. Optimal perioperative anesthesia management for gynecologic interstitial brachytherapy

    Directory of Open Access Journals (Sweden)

    Alison A. Nielsen

    2017-06-01

    Full Text Available Purpose : To propose an optimal perioperative pain management clinical care pathway for interstitial brachytherapy for gynecologic cancer based on our interdepartmental experience. Material and methods : We conducted a retrospective review of 23 women who underwent 32 interstitial brachytherapy procedures for gynecological cancers, analyzing patient demographics, type of anesthetic, medications, postoperative pain scores, adverse events, and delays in discharge. We measured the association of postoperative nausea and/or vomiting (PONV with hydromorphone use, and postoperative pain scores and total narcotic administration with type of anesthesia. Results : In 91% of patients postoperative pain was managed with an epidural infusion plus, as needed (PRN, IV or patient controlled analgesia (PCA narcotics. The most common postoperative adverse event was PONV (53%, followed by delirium (22%. Hospital discharge was delayed, at least by one night, in 26% of patients. Use of a basal rate on the PCA was associated with all cases of delayed discharge from over-sedation and PONV. The use of 5 mg or more of intravenous (IV hydromorphone during the first 24-hours postoperatively was associated with PONV (p = 0.01. Use of a basal PCA was associated with delirium (p = 0.03. Postoperative pain scores were not significantly associated with the type of anesthesia. Conclusions : Interstitial gynecologic brachytherapy requires a multidisciplinary effort for optimal perioperative management. Our study outlines the appropriate preoperative, intraoperative, and postoperative anesthesia clinical care pathway. Decreased narcotic use during hospitalization and utilization of a patient-directed infusion may decrease side effects and allow for a more efficient hospital discharge.

  3. Salvage robot-assisted radical prostatectomy after brachytherapy: our experience

    Directory of Open Access Journals (Sweden)

    A. V. Govorov

    2014-11-01

    Full Text Available In case of recurrence of prostate cancer after radiation therapy patient may be offered salvage radical prostatectomy (both open and laparoscopic/robotic, hormone therapy, and a number of alternative techniques such as salvage cryoablation, HIFU-therapy and brachytherapy. Results of monitoring of patients for 10 years after salvage treatment of prostate cancer are known only after salvage prostatectomy. Technically radical prostatectomy after radiation therapy is associated with a large number of complications if compared with primary radical prostatectomy. The most frequent complications after salvage prostatectomy include incontinence, stricture formation of urethrovesical anastomosis, rectal injury, acute urinary retention and infectious complications.

  4. Salvage robot-assisted radical prostatectomy after brachytherapy: our experience

    Directory of Open Access Journals (Sweden)

    A. V. Govorov

    2014-01-01

    Full Text Available In case of recurrence of prostate cancer after radiation therapy patient may be offered salvage radical prostatectomy (both open and laparoscopic/robotic, hormone therapy, and a number of alternative techniques such as salvage cryoablation, HIFU-therapy and brachytherapy. Results of monitoring of patients for 10 years after salvage treatment of prostate cancer are known only after salvage prostatectomy. Technically radical prostatectomy after radiation therapy is associated with a large number of complications if compared with primary radical prostatectomy. The most frequent complications after salvage prostatectomy include incontinence, stricture formation of urethrovesical anastomosis, rectal injury, acute urinary retention and infectious complications.

  5. Use of Monte Carlo Methods in brachytherapy; Uso del metodo de Monte Carlo en braquiterapia

    Energy Technology Data Exchange (ETDEWEB)

    Granero Cabanero, D.

    2015-07-01

    The Monte Carlo method has become a fundamental tool for brachytherapy dosimetry mainly because no difficulties associated with experimental dosimetry. In brachytherapy the main handicap of experimental dosimetry is the high dose gradient near the present sources making small uncertainties in the positioning of the detectors lead to large uncertainties in the dose. This presentation will review mainly the procedure for calculating dose distributions around a fountain using the Monte Carlo method showing the difficulties inherent in these calculations. In addition we will briefly review other applications of the method of Monte Carlo in brachytherapy dosimetry, as its use in advanced calculation algorithms, calculating barriers or obtaining dose applicators around. (Author)

  6. LOW-DOSE RATE BRACHYTHERAPY FOR PROSTATE CANCER: DIFFERENT INDICATIONS – DIFFERENT RESULTS

    Directory of Open Access Journals (Sweden)

    V. A. Biryukov

    2014-07-01

    Full Text Available In Russia, there is presently a growing interest in low-dose intratissue radiotherapy (brachytherapy for locally advanced prostate cancer (PC. Since its inception, current brachytherapy has undergone a number of significant changes in terms of improved visualization and better treatment planning and monitoring, which is sure to have affected the higher quality of their performance and better long-term results. The main purpose of the given paper is to generalize the data of foreign investigators who have the greatest experience with brachytherapy for its further use in the treatment of patients with locally advanced PC under the conditions of Russian clinics.

  7. Breast Gangrene

    Directory of Open Access Journals (Sweden)

    Husasin Irfan

    2011-08-01

    Full Text Available Abstract Background Breast gangrene is rare in surgical practice. Gangrene of breast can be idiopathic or secondary to some causative factor. Antibiotics and debridement are used for management. Acute inflammatory infiltrate, severe necrosis of breast tissue, necrotizing arteritis, and venous thrombosis is observed on histopathology. The aim of was to study patients who had breast gangrene. Methods A prospective study of 10 patients who had breast gangrene over a period of 6 years were analyzed Results All the patients in the study group were female. Total of 10 patients were encountered who had breast gangrene. Six patients presented with breast gangrene on the right breast whereas four had on left breast. Out of 10 patients, three had breast abscess after teeth bite followed by gangrene, one had iatrogenic trauma by needle aspiration of erythematous area of breast under septic conditions. Four had history of application of belladonna on cutaneous breast abscess and had then gangrene. All were lactating female. Amongst the rest two were elderly, on