Validation of proton dose calculation on scatter corrected 4D cone beam computed tomography using a porcine lung phantom

Abstract Proton therapy treatment for lungs remains challenging as images enabling the detection of inter- and intra-fractional motion, which could be used proton dose adaptation, are not readily available. 4D computed tomography (4DCT) provides high image quality but is rarely available in-room, while in-room cone beam (4DCBCT) suffers from limitations stemming mostly scatter detection. This study investigated feasibility using virtual (4DvCT) a prior phase-per-phase correction algorithm yielding corrected (4DCBCT cor ), can calculation. 4DCT 4DCBCT scans porcine lung phantom, generated reproducible ventilation, were acquired with matching breathing patterns. Diffeomorphic Morphons, deformable registration algorithm, was to register mid-position yield 4DvCT. The reconstructed motion-aware reconstruction based on spatial temporal regularization (MA-ROOSTER). Successively each phase, digitally radiographs 4DvCT, simulated without scatter, exploited correct in corresponding CBCT projections. then MA-ROOSTER projections same settings deformation vector fields those already reconstructing 4DCBCT. 4DvCT evaluated phase-by-phase, performing calculations comparison ground truth by means dose-volume-histograms (DVH) gamma pass-rates (PR). For accumulated doses, DVH parameters deviated at most 1.7% 2.0% case. PR (2%, 2 mm) criterion 10% threshold least 93.2% 94.2% respectively. technique enabled accurate calculation, indicates potential applicability clinical scans.