ESTRO 2024 - Abstract Book

S4222

Physics - Intra-fraction motion management and real-time adaptive radiotherapy

ESTRO 2024

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[2] Boye, D., Lomax, T., & Knopf, A. (2013). Mapping motion from 4D-MRI to 3D-CT for use in 4D dose calculations: a technical feasibility study. Medical physics, 40(6), 061702. https://doi.org/10.1118/1.4801914

[3] Duetschler, A., Bauman, G., Bieri, O., Cattin, P. C., Ehrbar, S., Engin-Deniz, G., Giger, A., Josipovic, M., Jud, C., Krieger, M., Nguyen, D., Persson, G. F., Salomir, R., Weber, D. C., Lomax, A. J., & Zhang, Y. (2022). Synthetic 4DCT(MRI) lung phantom generation for 4D radiotherapy and image guidance investigations. Medical physics, 49(5), 2890–2903. https://doi.org/10.1002/mp.15591

1077

Digital Poster

Comparing a software-enabled and an add-on hardware-based motion monitoring system for prostate SABR

Chandrima Sengupta 1 , Doan T Nguyen 1,2 , Yuanyuan Ge 3 , Michael Grace 3 , Cameron Hall 3 , Brendan Whelan 2 , Michael G Jameson 4,5 , Peter McLoone 6 , Alicja Kaczynska 1 , Paul Liu 2 , Paul Keall 1,2 1 Image X Institute, The University of Sydney, School of Health Sciences, Sydney, Australia. 2 SeeTreat Medical, Engineering and development, Sydney, Australia. 3 GenesisCare, Hurstville, Sydney, Australia. 4 GenesisCare, St. Vincent's Clinic, Sydney, Australia. 5 University of New South Wales, School of Clinical Medicine, Medicine and Health, Sydney, Australia. 6 GenesisCare, Alexandria, Sydney, Australia

Purpose/Objective:

Real-time intrafraction motion management for prostate cancer patients reduced toxicity by 50% in the MIRAGE trial. 1 This clinical benefit was demonstrated on an MRI-Linac, which can be inaccessible due to the higher cost compared with standard linacs. Options for motion management on standard linacs include both software enabled real-time and supplemental hardware based intermittent intrafraction motion monitoring systems. From a cost and accessibility perspective, software-enabled followed by dedicated hardware-based intrafraction motion management systems supplementing a standard linac are the most appealing. The aim of this research was to compare the geometric accuracy between a software-enabled real-time and a supplemental hardware-based intermittent intrafraction motion management system for prostate SABR.

Material/Methods:

KIM, 2 a software-enabled real-time motion monitoring system which uses the on-board kilovoltage x-ray system, and ExacTrac Dynamic (Brainlab AG, Munich, Germany), 3 a supplemental intermittent intrafraction motion management system which uses two dedicated x-ray sources, were connected to a Versa HD (Elekta AB, Stockholm, Sweden) linac. A treatment plan using the TROG 15.01 SPARK 2 guidelines was used, with the only modification being a 2 mm CTV PTV margin following the MIRAGE trial. 1 To enable ground truth motion, an open-source robot 4 programmed with