Open AccessHow important is the dose rate sensitivity of 2D and 3D radiation dosimeters?
Author(s) -
Yves De Deene
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1305/1/012059
Subject(s) - dosimeter , dose rate , percentage depth dose curve , calibration , imaging phantom , nuclear medicine , radiation , materials science , dosimetry , biomedical engineering , medicine , medical physics , mathematics , optics , ionization chamber , physics , statistics , ion , quantum mechanics , ionization
Several kinds of chemical 3D radiation dosimeters have been fabricated to acquire the dose distribution in clinical radiotherapy. A legitimate concern with every new dosimeter is its dose rate dependent response because, the dose rate in each point of the phantom during a clinical treatment is unknown. Unfortunately, many 3D dosimeters have shown some degree of dose rate dependence. In practice, radiation dosimeters are mostly calibrated using a calibration curve that is obtained by irradiating calibration vials with different doses but using a fixed dose rate. Therefore, when applying a dose calibration to an experimentally obtained dose distribution, a deviation between the measured dose distribution and the actual dose distribution can be expected. In this computational study, the effect of a dose rate dependent dosimeter response on a theoretical dose distribution has been investigated. In order to compare the effect of dose rate, a gamma evaluation is performed between the predefined dose distribution and the dose distribution that is affected by a dose rate dependent radiation response. It is found that a dose rate difference of -10%, results in a gamma pass rate of 100% in the 3D dose distribution.