Evaluation of the applicability of MOSFET detectors in radiotherapy

• The response of MOSFET detectors to six different set-up factors affecting the measurements was investigated.
• Detector readouts were compared with doses calculated by different treatment planning systems.
• Doses were measured and calculated for the conventional and IMRT therapies using 6 and 15 MV beams.
• The differences between planned and MOSFET measured doses delivered to the selected target areas are presented.
• Three different plans for thorax and pelvis areas were studied.

MOSFET detectors of 1 mVcGy−1 sensitivity were tested for the accuracy of absorbed dose measurements in radiation therapy with the use of photon and electron beams. Before a detector was used in the study, several calibration coefficients were determined to allow for different factors affecting its operation. Then, the detector exposure response was compared with the dose calculated in the anthropomorphic phantom by the Monaco and MasterPlan treatment planning systems. MOSFET detectors were placed inside the phantom during the irradiation. Three different plans for thorax and pelvis areas were studied. The paper presents the differences between planned and MOSFET measured doses delivered to the selected target areas using conventional and IMRT techniques.