ESTRO 2024 - Abstract Book

S4308

Physics - Intra-fraction motion management and real-time adaptive radiotherapy

ESTRO 2024

Conclusion:

This analysis reveals an association between PTV volume and longer treatment times in MR-Linac radiation treatments. To optimize patient care and reduce treatment durations, the development and implementation of tools aimed at enhancing contouring and planning processes are essential.

Keywords: MR-Linac, optimization, real-time adaptive RT

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Digital Poster

Impact of CT Selection on Dose Accumulation in Adaptive Radiotherapy for Head and Neck Patients

Evangelia Choulilitsa 1,2 , Andreas Johan Smolders 1,2 , Barbara Bachtiary 1 , Damien Charles Weber 1,3,4 , Antony John Lomax 1,2 , Francesca Albertini 1 1 Paul Scherrer Institute, Center for Proton Therapy, Villigen, Switzerland. 2 ETH, Department of Physics, Zurich, Switzerland. 3 University Hospital Zurich, Department of Radiation Oncology, Zurich, Switzerland. 4 Inselspital, Bern University Hospital, University of Bern, Department of Radiation Oncology, Bern, Switzerland

Purpose/Objective:

In an online adaptive radiotherapy workflow, treatment plans are optimized based on daily CT images. To accurately quantify the total delivered dose, these daily doses need to be accumulated on a reference image. Whilst typically, this is the original planning CT, it is currently unclear if this is the best reference CT. This study investigates the dosimetric impact of selecting different reference CT for dose accumulation in adaptive radiotherapy for head and neck patients.