A dosimetric comparison of helical tomotherapy treatment delivery with real-time adaption and no motion correction

Jonathan Hindmarsh; Scott Crowe; Julia Johnson; Chandrima Sengupta; Jemma Walsh; Sonja Dieterich; Jeremy Booth; Paul Keall

doi:10.1016/j.phro.2025.100741

A dosimetric comparison of helical tomotherapy treatment delivery with real-time adaption and no motion correction

Phys Imaging Radiat Oncol. 2025 Mar 5:34:100741. doi: 10.1016/j.phro.2025.100741. eCollection 2025 Apr.

Authors

Jonathan Hindmarsh¹, Scott Crowe², Julia Johnson¹, Chandrima Sengupta¹, Jemma Walsh², Sonja Dieterich³, Jeremy Booth^{4

5}, Paul Keall¹

Affiliations

¹ Image X Institute, Faculty of Medicine and Health, University of Sydney, Eveleigh, NSW, Australia.
² Cancer Care Services, Royal Brisbane and Women's Hospital, Herston, QLD, Australia.
³ Department of Radiation Oncology, UC Davis Medical Center, Sacramento, CA, USA.
⁴ Northern Sydney Cancer Centre, Royal North Shore Hospital, St Leonards, NSW, Australia.
⁵ Institute of Medical Physics, School of Physics, University of Sydney, Camperdown, NSW, Australia.

Abstract

This study assesses the ability of a helical tomotherapy system equipped with kV imaging and optical surface guidance to adapt to motion traces in real-time. To assess the delivery accuracy with motion, a unified testing framework was used. The average 2 %/2 mm γ-fail rates across all lung traces were 0.1 % for motion adapted and 17.4 % for no motion correction. Average 2 %/2 mm γ-fail rates across all prostate traces were 0.4 % for motion adapted and 12.2 % for no motion correction. Real-time motion adaption was shown to improve the accuracy of dose delivered to a moving phantom compared with no motion adaption. MeSH Keywords: Radiotherapy, image-guided; Radiation therapy, targeted.

Keywords: Helical tomotherapy; MLC tracking; Organ motion; Real-time adaptive radiotherapy.