ESTRO 2024 - Abstract Book

S4030

Physics - Inter-fraction motion management and offline adaptive radiotherapy

ESTRO 2024

This feasibility study presents a novel synthetic 4D-MIR generation method that opens a relevant opportunity for future clinical studies to improve MRgRT when MR-linac is unavailable. Indeed, it was demonstrated that predictions of the deformation magnitude based on prior knowledge of the respiratory motion modeling represent a feasible method to generate on-board synthetic 4D-MRI from 4D-CBCT images if the respiratory and anatomical reproducibility are ensured between the simulation and on-board images. Additionally, it is emphasized in this context the relevance of understanding the physical meaning of the features activated by AI methods applied to clinical images in order to verify the model reliability

Keywords: MRgRT, CNN, 4D-MRI

References:

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1325

Proffered Paper

Robust dose mapping accounting for per-organ deformations uncertainties

Christopher Thompson 1 , Stina Svensson 2 , Louise Murray 3,4 , Ane Appelt 1,4 , Robin Prestwich 3 , Michael Nix 1