ESTRO 2025 - Abstract Book

S3641

Physics - Quality assurance and auditing

ESTRO 2025

Conclusion: The transversal radiation source position offsets can be detected using Star Shot test and the results can be used to guide transversal source position corrections.

Keywords: Star Shot, Radiation source position, QA

References: [1] Kulmala A., Ikäheimonen P., Petrow P., Mikkola K. and Halkoaho J. 2024 The accuracy of isocentre position in the vertical-lateral plane in clinical linear accelerators, ECMP congress, Münich [2] Ikäheimonen P., Petrow P., Mikkola K., Halkoaho J. and Kulmala A. 2024 Star Shot film analysis for the accuracy of gantry angle and isocenter radius in the MRIdian radiotherapy device, AAPM annual congress, Los Angeles [3] Mikkola K., Ikäheimonen P., Petrow P., Halkoaho J. and Kulmala A. 2024 Star Shot film analysis for gantry angle and isocenter radius in Halcyon treatment units, ESTRO annual congress, Glasgow

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Digital Poster Analysis of independent dose calculation and measurement systems for patient specific quality assurance. Olga - Toumanidou 1,2 , Emma Dyke 1 , Sally Fletcher 1 1 Medical Physics, Bristol Haematology and Oncology Centre, Bristol, United Kingdom. 2 Medical Physics, Velindre Cancer Centre, Cardiff, United Kingdom Purpose/Objective: This study compared and evaluated the performance of different patient-specific quality assurance (PSQA) systems, including two independent dose calculation systems—Compass (V4.1.3, IBA) and myQA iON (V2.1.0, IBA)—and two measurement systems—MatrixX (IBA Dosimetry, GmbH, Germany) and SRS Detector (IBA Dosimetry, GmbH, Germany). Additionally, the study explored the correlation between treatment plan complexity indices and PSQA measurement results, assessing their potential utilisation as predictive tools for PSQA outcomes. Finally, the sensitivity of the measurement systems to detect MLC position errors was evaluated.