Abstract：
:In many of brachytherapy procedures, a large amount of radioactive sources are used to deliver desired doses to the target volume. It is both the federal regulation recommendation (U.S. Nuclear Regulatory Commission, 10 CFR 35.432) and recommendations of the American Association of Physicists in Medicine (AAPM) [Kutcher et al., Med. Phys. 21, 581-618 (1994); Nath et al., Med. Phys. 24, 1557-1598 (1997)] that users independently verify the sources' strength. Though the reports of AAPM Task Group 40 [Kutcher et al., Med. Phys. 21, 581-618 (1994)] and 56 [Nath et al., Med. Phys. 24, 1557-1598 (1997)] have made specific recommendations on the assay of brachytherapy sources, the relevant statistical significance of the recommendations remain unanswered. In this study, statistical theories were used and a method was presented to quantify the assay process of brachytherapy sources and to evaluate the recommendations. The results showed that the quality of a source assay process was dependent on the measured source strength deviation and number of assayed sources. Its dependence on the total number of sources becomes statistically insignificant if the total number is large enough. It was concluded that the assay process can be determined by the obtained assay information, instead of a preset percentage of total sources. It was further found that the use of manufacturer's stated strength value may possibly lead to bigger uncertainty in source strength accuracy, unless the manufacturer's stated strength is the measured mean value of all the ordered sources.
journal_name
Med Physjournal_title
Medical physicsauthors
Yue NJ,Haffty BG,Yue Jdoi
10.1118/1.2734723subject
Has Abstractpub_date
2007-06-01 00:00:00pages
1975-82issue
6eissn
0094-2405issn
2473-4209journal_volume
34pub_type
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