Assessment of the dosimetric impact of intra-fraction motion during frameless treatment delivery on GammaKnife® Icon™.
Year: 2022
Type: article
Abstract: Icon™ treatments. By quantifying dosimetric robustness at increasing high definition motion management (HDMM) gating tolerances, this study investigated the possibility of increasing the HDMM threshold for patients treated at our centre from our current standard of 1 mm. Methods: Motion was retrospectively simulated by shifting the stereotactic co-ordinates of shots in treatment plans using three motion models. Dosimetric quality indicators of original and shifted plans were compared. Influence of target location and size was determined. Results: =0.040-0.309). No location dependence was observed. Conclusion: HDMM tolerances up to and including 3mm all resulted in negligible changes in PCI and GI. Target coverage exhibited greater sensitivity to motion, but only at 3mm was the target coverage reduced below local planning aims. Our HDMM tolerance could therefore potentially be increased to 1.5mm, with likely benefits to treatment delivery efficiency.
Source: PubMed Central
Authors: Hannah Taylor, Peter Fallows, Gavin Wright
Institution: St James's University Hospital
Language: English
Subfield: Radiation
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4322758499