Abstract:
:A phantom study for dosimetry in the urethra using alanine/ESR during (192)Ir HDR brachytherapy of prostate cancer is presented. The measurement method of the secondary standard of the Physikalisch-Technische Bundesanstalt had to be slightly modified in order to be able to measure inside a Foley catheter. The absorbed dose to water response of the alanine dosimetry system to (192)Ir was determined with a reproducibility of 1.8% relative to (60)Co. The resulting uncertainty for measurements inside the urethra was estimated to be 3.6%, excluding the uncertainty of the dose rate constant Lambda. The applied dose calculated by a treatment planning system is compared to the measured dose for a small series of (192)Ir HDR irradiations in a gel phantom. The differences between the measured and applied dose are well within the limits of uncertainty. Therefore, the method is considered to be suitable for measurements in vivo.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Anton M,Wagner D,Selbach HJ,Hackel T,Hermann RM,Hess CF,Vorwerk Hdoi
10.1088/0031-9155/54/9/022subject
Has Abstractpub_date
2009-05-07 00:00:00pages
2915-31issue
9eissn
0031-9155issn
1361-6560pii
S0031-9155(09)05490-6journal_volume
54pub_type
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