Comparison of the New MOSkin Detector and Fiber Optic Dosimetry System for Radiotherapy

Abstract

In radiotherapy, interest in real-time dosimetry stems from the desire to monitor the dose delivered to the target volume and the surrounding normal tissue to enable clinicians to track the progress of the treatment, and prevent surrounding tissue from receiving too much radiation dose. In this study, the dosimetric performance of the new MOSkin dosimeter and a Bicron BCF-20 scintillating fiber was compared to depth dose measurements taken with a Farmer-type ionization chamber. The performance of the MOSkin and BCF-20 detectors in the build-up region of the depth dose curve, where the dose gradient is steep, is also compared to readings taken with an Attix chamber. At depths greater than 15 mm, the MOSkin readings deviated from the ion chamber readings by up to 4%, while the fiber optic dosimeter always remained within 3% of the ionization chamber reading. In the build-up region, the MOSkin proved quite capable of measuring the dose at build up when compared to the Attix chamber results, while the fiber optic dosimeter was not able to measure the dose in this region with a high level of precision due to the thick sensitive volume of the scintillating crystal.