Use of optically stimulated luminescence dosimeter and radiophotoliminescent glass dosimeter for dose measurement in dual-source dual-energy computed tomography

摘要

We aimed to evaluate properties of optically stimulated luminescence dosimeters (OSLDs) and radiophotoluminescent glass dosimeters (RPLDs) used in dual-source dual-energy (DE) computed tomography (DECT) dosimetry. Energy dependence was evaluated in single-energy (SE) and DE modes, and their relative dose responses differed by 3.8% and 6.6% under equivalent effective energy with OSLD and RPLD, respectively. Dose variation was evaluated using coefficients of variation of dose values from 10 dosimeters, and dose variation of OSLD and RPLD in SE mode ranged from 2.1 to 3.0% and from 2.1 to 2.8%, and those in the DE mode were 1.8 and 2.6%, respectively. Dose linearity was evaluated from 1 to 150 mGy, and linear relationships of dose response were observed between the dosimeters and the ionization chamber (correlation coefficients >= 0.9991). Angular dependence was evaluated from - 90 degrees to + 90 degrees, and it was smaller in DE mode than in SE mode for OSLD. The normalized response of RPLD was higher at +/- 30 degrees and +/- 60 degrees and lower at - 90 degrees in SE and DE modes. This study demonstrated both OSLD and RPLD can perform dosimetry in dual-source DECT with small influence of the properties of the dosimeters compared with that in SECT.