ESTRO 2024 - Abstract Book

S3351

Physics - Detectors, dose measurement and phantoms

ESTRO 2024

Dose maps from a volume of 50x50x40 mm 3 were successfully read out from the YSO:Ce crystal with a spatial resolution of 0.28x0.28x0.50 mm 3 after irradiation with overlapping 10x10 mm 2 jaw-defined fields of photons and irradiation with four proton pencil beams of different energies. The reproducibility of the system was found to be within 2% by investigations of the readout after irradiation with a photon treatment plan consisting of two opposing fields, yielding a homogeneous dose distribution. A promising linearity was observed in the fractional OSL response, as a function of dose-averaged LET value, from the dual-composite OSL-based film across an area of 60x60 mm 2 with a spatial resolution of 1.16x1.16 mm 2 .

Conclusion:

We present the use of OSL for measuring dose distributions in 3D and combined dose/LET maps in 2D with a reusable dosimeter. We have demonstrated a 3D readout with high spatial resolution from a volume of clinically relevant size using both photon and proton irradiations. Moreover, we have demonstrated a reusable, dual-composite, OSL-based dosimeter for measuring the dose and LET map in 2D simultaneously. The presented results demonstrate the feasibility of 3D, OSL-based dosimetry, and LET mapping in 2D, with the reusability of the dosimeters providing a promising solution to the challenges found in the currently available 3D dosimeters

Keywords: 3D dosimetry, LET mapping, OSL

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