Premium
Evaluation of the accuracy of fetal dose estimates using TG‐36 data
Author(s) -
Kry Stephen F.,
Starkschall George,
Antolak John A.,
Salehpour Mohammad
Publication year - 2007
Publication title -
medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.473
H-Index - 180
eISSN - 2473-4209
pISSN - 0094-2405
DOI - 10.1118/1.2710332
Subject(s) - medicine , nuclear medicine , dosimetry , fetus , radiation dose , radiation therapy , field size , pregnancy , biology , genetics
The American Association of Physicists in Medicine Radiation Therapy Committee Task Group 36 report (TG‐36) provides guidelines for managing radiation therapy of pregnant patients. Included in the report are data that can be used to estimate the dose to the fetus. The purpose of this study is to evaluate the accuracy of these fetal dose estimates as compared to clinically measured values. TG‐36 calculations were performed and compared with measurements of the fetal dose made in vivo or in appropriately‐designed phantoms. Calculation and measurement data was collected for eight pregnant patients who underwent radiation therapy at the MD Anderson Cancer Center as well as for several fetal dose studies in the literature. The maximum measured unshielded fetal dose was 47 cGy , which was 1.5% of the prescription dose. For all cases, TG‐36 calculations and measured fetal doses differed by up to a factor of 3—the ratio of the calculated to measured dose ranged from 0.34 to 2.93. On average, TG‐36 calculations underestimated the measured dose by 31%. No significant trends in the relationship between the calculated and measured fetal doses were found based on the distance from, or the size of, the treatment field.