ESTRO 2024 - Abstract Book

S3995

Physics - Inter-fraction motion management and offline adaptive radiotherapy

ESTRO 2024

Results:

The average shifts in vertical (VRT), longitudinal (LNG) and lateral (LAT) direction showed no significant difference between the two setup methods (p > 0.05) (table 1: Preposition). However, there was a significant difference in variance in all directions (p < 0.01), indicating that SGRT provided less variations while maintaining mean accuracy similar to the conventional skin marker method. For intrafraction motion the mean population error (Mpop), systematic population error (Σ) and random population error (σ) was below 1 mm in all directions (table 1: Intrafraction motion). Mpop was 0 mm for LNG and LAT, but 0.3 mm for VRT, which was significantly different from zero (p < 0.01). In general, a larger variation was observed in VRT and LNG direction compared to LAT with movements up to 3.6 mm in VRT. The average time between delivery of the two main fields was 97 ± 34 sec.