ESTRO 2025 - Abstract Book

S2647

Physics - Detectors, dose measurement and phantoms

ESTRO 2025

Fig. 1. Gamma Passing Rate for PTVs and OARs verification obtained using MatriXX PT and EBT4 films.

Conclusion: With proper characterization and calibration, EBT4 films prove to be a reliable tool for PSQA in proton therapy. The PSQA results for the OARs and PTVs in acoustic neuroma obtained using films are comparable to results from clinical used method. An additional advantage of GAFChromics is a significant increase in measurement resolution.

Keywords: proton therapy, Vestibular Schwannoma, Gafchromics

References: 1. Saraf A, Pike LRG, Franck KH, et al. Fractionated Proton Radiation Therapy and Hearing Preservation for Vestibular Schwannoma: Preliminary Analysis of a Prospective Phase 2 Clinical Trial . Neurosurgery. 2022;90(5):506-514. 2. Barnes CJ, Bush DA, Grove RI, et al. Fractionated Proton Beam Therapy for Acoustic Neuromas: Tumor Control and Hearing Preservation. Int J Part Ther. 2018;4(4):28-36. 3. Apicella G. et al. Radiotherapy for vestibular schwannoma: Review of recent literature results . RPOR 2016:21;399-406 4. Santacroce A, Trandafirescu MF, Levivier M, et al. Proton beam radiation therapy for vestibular schwannomas-tumor control and hearing preservation rates: a systematic review and meta-analysis . Neurosurg Rev. 2023 Jul 4;46(1):163.

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Digital Poster Evaluation of a new generation 2D array prototype for carbon ion dosimetry Loïc Grevillot 1 , Carlos Miguel Figueiredo de Carvalho 1 , Peter Kuess 2 , Javier Pérez-Curbelo 3 1 Medical Physics, MedAustron, Wiener Neustadt, Austria. 2 Radiation Oncology, Medical University of Vienna, Vienna, Austria. 3 Experimental Physics, Instituto de Física Corpuscular (IFIC), CSIC-UV, Valencia, Spain Purpose/Objective: Four light ion beam therapy (LIBT) centers are currently operational in Europe, delivering scanned proton and carbon ion beams. Patient Specific QA (PSQA) is conducted using the 3D-block hardware from PTW, constituted of 24 pinpoint ionization chambers. Unfortunately, no dedicated commercial software is available and thus home-made scripts are required to prepare, execute, analyze and report the PSQA. In this work, a new generation 2D array prototype was