ESTRO 2025 - Abstract Book

S4109

RTT - Patient care, preparation, immobilisation and IGRT verification protocols

ESTRO 2025

Conclusion: Our current protocol provides sufficient information for confidence in target localisation, and the independent review of images showed consistency between reviewers. Our results favour the continued use of the 3-minute CBCT as the scores were higher than for the 2-minute scan for all patients. The 4D-CBCT has been shown to add little value. We are currently the only centre in the UK to acquire a 4D-CBCT for every patient, although it is used in a number of centres worldwide. This may be improved by further image optimisation. Based on the findings presented here we conclude that 4D-CBCT may be omitted from the cSABR IGRT process, with the option to add if deemed beneficial to individual patients, which will reduce dose to the patient and overall treatment time.

Keywords: SABR, IGRT, Cardiac

References: 1. Cuculich, P. S., Schill, M. R., Kashani, R., Mutic, S., Lang, A., Cooper, D., Faddis, M., Gleva, M., Noheria, A., Smith, T. W., Hallahan, D., Rudy, Y., & Robinson, C. G. (2017). Noninvasive cardiac radiation for ablation of ventricular tachycardia. The New England Journal of Medicine, 377 (24), 2325–2336. https://doi.org/10.1056/NEJMoa1613773 2. Khan, M., Sandhu, N., Naeem, M., Ealden, R., Pearson, M., Ali, A., Honey, I., Webster, A., Eaton, D., & Ntentas, G. (2022). Implementation of a comprehensive set of optimised CBCT protocols and validation through imaging quality and dose audit. The British Journal of Radiology, 95 (1137), 20220070. https://doi.org/10.1259/bjr.20220070

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Digital Poster Comparative Analysis of Surface-guided Radiotherapy and Cone-beam CT Setup Accuracy in Left-Sided Breast Deep Inspiration Breath-hold Radiotherapy Guan-Ling Chen 1 , Yao-Ting Lu 1 , Jia-Qian Zeng 1 , Yen-Ting Liu 2,3,1 , Pei-Hsuan Lee 1,4,5 1 Oncology, National Taiwan University Hospital, Taipei, Taiwan. 2 Biomedical Engineering, National Taiwan University, Taipei, Taiwan. 3 Oncology, National Taiwan University Hospital Yunlin Branch, Yunlin, Taiwan. 4 Oncology, National Taiwan University Cancer Center, Taipei, Taiwan. 5 Epidemiology and Prevention Medicine, National Taiwan University, Taipei, Taiwan