ESTRO 2025 - Abstract Book

S3614

Physics - Quality assurance and auditing

ESTRO 2025

Figure 1: CIRS dynamic-cardiac-phantom and newly developed rod with “L”-insert for catheter-, film- and ion-chamber measurements.

Results: In the phantom, cardiac motion is realized as linear motion in SI-direction and a roll-rotation for AP- and LR-motion. Blurring due to cardiac motion was evaluated by contouring the 12 ml “L”-structure in different CT-series and resulted in 12.1 ml (static) vs. 12.4 ml (small motion) vs. 13.2 ml (larger motion). The target transfer with CARDIO-RT was successfully performed (Figure 2). First dose-measurements show minimal influences on the dose distribution for small cardiac motion (-0.2%) compared to larger cardiac motion (-3.7%). Limitations of the phantom are the lack of impedance measurements for catheter localization needed for respiratory-gating and other EAM-systems as well as the differential insert start-position based on the programmed cardiac motion.