4 research outputs found
Grundlegende Untersuchungen zum Dosisueberhoehungseffekt im PMMA
Available from the library of Tuebingen Univ. (DE) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman
Exposure of treating physician to radiation during prostate brachytherapy using iodine-125 seeds
Background and Purpose: Only sparse reports have been made about radiation exposure of the treating physician during prostate seed implantation. Therefore, thermoluminescence dosimeter (TLD) measurements on the index fingers and the backs of both hands were conducted. Material and Methods: Stranded iodine-125 seeds with a mean apparent activity of 27.4 MBq per seed were used. During application, the treating physician manipulated the loaded needle with the index fingers, partially under fluoroscopic control. Four physicians with varying experience treated 24 patients. The radiation exposure was determined with TLD-100 chips attached to the index fingertips and the backs of hands. Radiation exposure was correlated with the physician`s experience. Results: The average brachytherapy duration by the most experienced physician was 19.2 min (standard deviation sigma = 1.2 min; novices: 34.8 min [sigma = 10.2 min]). The mean activity was 1,703 MBq (sigma = 123 MBq), applied with 16.3 needles (sigma = 2.5 needles; novices: 1,469 MBq [sigma = 229 MBq]; 16.8 needles [sigma = 2.3 needles]). The exposure of the finger of the ``active hand`` and the back of the hand amounted to 1.31 mSv (sigma = 0.54 mSv) and 0.61 mSv (sigma = 0.23 mSv), respectively (novices: 2.07 mSv [sigma = 0.86 mSv] and 1.05 mSv [sigma = 0.53 mSv]). Conclusion: If no other radiation exposure needs to be considered, an experienced physician can perform about 400 applications per year without exceeding the limit of 500 mSv/year; for novices, the corresponding figure is about 200
AAPM recommendations on medical physics practices for ocular plaque brachytherapy: Report of task group 221
The American Association of Physicists in Medicine (AAPM) formed Task Group 221 (TG-221) to discuss a generalized commissioning process, quality management considerations, and clinical physics practice standards for ocular plaque brachytherapy. The purpose of this report is also, in part, to aid the clinician to implement recommendations of the AAPM TG-129 report, which placed emphasis on dosimetric considerations for ocular brachytherapy applicators used in the Collaborative Ocular Melanoma Study (COMS). This report is intended to assist medical physicists in establishing a new ocular brachytherapy program and, for existing programs, in reviewing and updating clinical practices. The report scope includes photon- and beta-emitting sources and source:applicator combinations. Dosimetric studies for photon and beta sources are reviewed to summarize the salient issues and provide references for additional study. The components of an ocular plaque brachytherapy quality management program are discussed, including radiation safety considerations, source calibration methodology, applicator commissioning, imaging quality assurance tests for treatment planning, treatment planning strategies, and treatment planning system commissioning. Finally, specific guidelines for commissioning an ocular plaque brachytherapy program, clinical physics practice standards in ocular plaque brachytherapy, and other areas reflecting the need for speci