Feasibility of dosimetry with optically stimulated luminescence detectors in magnetic fields

Readout with the portable reader yielded package standard deviations of 1-2% and revealed no significant relation between dose response and magnetic field strength, while readout with the Risø reader resulted in standard deviations of only 1% and a significant decrease in response of −1.3% per T (95%-confidence interval: −1.9% to −0.7%). The angular dependence was not significantly influenced by the magnetic field. The small decrease in dose response supports the applicability of the OSL technique in MR-guided radiation therapy devices. We expect that no additional magnetic field correction factor has to be used when a calibration of the detectors in the magnetic field of such a device is performed.