Linear energy transfer-independent calibration of radiochromic film for carbon-ion beams

Mutsumi Tashiro; Motohiro Kawashima

doi:10.1016/j.phro.2022.08.001

Linear energy transfer-independent calibration of radiochromic film for carbon-ion beams

Phys Imaging Radiat Oncol. 2022 Aug 8:23:140-143. doi: 10.1016/j.phro.2022.08.001. eCollection 2022 Jul.

Authors

Mutsumi Tashiro¹, Motohiro Kawashima¹

Affiliation

¹ Gunma University Heavy Ion Medical Center, 3-39-22 Showa-Machi, Maebashi, Gunma 371-8511, Japan.

Abstract

For carbon-ion beams, radiochromic film response depends on the dose and linear energy transfer (LET). For film dosimetry, we developed an LET-independent simple calibration method for a radiochromic film for specific therapeutic carbon-ion beams. The measured film doses were calibrated with a linear function within 5% error. The penumbra positions of the films were consistent with the differences from the planned ones within ~0.4 mm. The results indicated sufficient accuracy for use as a tool for the confirmation of the penumbra position of the fields.

Keywords: Carbon-ion beam therapy; Film dosimetry in spacer; Gafchromic RTQA2 film; LET-independent simple calibration; Radiochromic film.