ESTRO 2024 - Abstract Book

S3662

Physics - Dose prediction, optimisation and applications of photon and electron planning

ESTRO 2024

Figure 1: Objective function values for 2-arc VMAT plans created for the C-shaped target with a 30° tilt. In a) dynamic collimator rotation plans are illustrated for combinations of offsets. In b) static collimator angle plans are illustrated for combinations of collimator angles. On top, a beam’s eye view of the PTV (in red), OAR (in blue) and MLC of the first optimization point is shown for the two arcs. For the three clinically motivated cases, the objective function is on average reduced by 4.8% (prostate case), 16.5% (head and neck case), and 9.7% (breast case) in the plans with dynamic collimator compared to the plans with static collimator angle. In Figure 2, dose-volume histograms of the dynamic and static collimator plans with a table angle of 30° are shown for the head and neck case.

Figure 2: Dose-volume histrograms of 2-arc non-coplanar (30° table angle) VMAT plans with and without dynamic collimator rotation for a head and neck case.

Conclusion: