Optimization of high dose-rate cervix brachytherapy; Part I: Dose distribution
Autor: | Bernd Uwe Sevin, James G. Schwade, Andre A. Abitbol, Christopher F. Serago, Andrew M. Cohen, Fahed Fayad, Pavel V. Houdek, Arnold M. Markoe, Jeffrey A. Fiedler, Alfred H. Brandon, Xiaodong Wu, Alan A. Lewin, Vincent Pisciotta, Hervy E. Averette |
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Rok vydání: | 1991 |
Předmět: |
Cancer Research
High energy medicine.medical_treatment Brachytherapy Cervix Uteri Dose distribution Radiotherapy High-Energy medicine Humans High activity Radiology Nuclear Medicine and imaging Cervix Radiation business.industry Radiotherapy Planning Computer-Assisted Radiotherapy Dosage Uterine cervix medicine.anatomical_structure Oncology Vagina Ovoid Female Nuclear medicine business Dose rate |
Zdroj: | International Journal of Radiation Oncology*Biology*Physics. 21:1621-1625 |
ISSN: | 0360-3016 |
DOI: | 10.1016/0360-3016(91)90341-z |
Popis: | Computer controlled high dose-rate (HDR) brachytherapy afterloading machines are equipped with a single, miniaturized, high activity Ir-192 source that can be rapidly moved in fine increments among several channels. Consequently, by appropriate programming of source dwell positions and times, the dose distribution can be optimized as desired. We have explored the optimization potential of this new technology for two applications: (a) cervix brachytherapy, and (b) transvaginal irradiation. Cervix brachytherapy with a gynecologic ring applicator was simulated by 48 sources of relative activities ranging from 0.17 to 1.00 that were equally distributed between the tandem and the ring. The results confirmed that the optimized distribution of physical doses are superior to those achievable with standard brachytherapy sources and applicators. For example, with five-point optimization, the relative dose-rate in the rectum was only 47% of that in point A; for standard application the dose rate was 47% higher. For transvaginal application 27 sources of relative activities between 0.07-0.79 were placed in the ring and a single source of unit strength in the tandem. Using dose distribution homogeneity as an optimization criterion, the results (+/- 2.5%) were again superior to those obtained for commonly used double ovoid (+/- 15%), linear cylinder (+/- 27%), or a "T" source (31%). |
Databáze: | OpenAIRE |
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