Evaluating participant experiences and tolerability with MR Linac imaging.

Introduction: Magnetic Resonance Image Guided Radiotherapy (MRIgRT) integrates MRI with a linear accelerator to enable adaptive treatment delivery. While technical feasibility is well established, patient experience during MR Linac imaging, especially outside treatment sessions, remains underexplored. This study evaluates tolerability, pre-scan anxiety, coping ability, willingness for future scans, and scan-induced symptoms in patients and non-patient volunteers. Materials and Methods: Participants who successfully underwent MR Linac imaging between November 2017 and December 2023 completed a bespoke MR Linac Participant Experience Questionnaire, developed by the PRIMER study team and informed by MRI patient experience literature. The questionnaire assessed pre-scan anxiety, coping, willingness for future scans, and scan-related symptoms using Likert-scale responses. Descriptive analyses summarised responses by participant group and anatomical site. Results: In total, 447 participants (319 patients; 128 non-patient volunteers) completed MR Linac imaging and the questionnaire. Overall tolerability was high, with 65 % strongly disagreeing they felt anxious prior to scanning and most participants reporting good coping ability. Variability was observed across anatomical sites: Participants undergoing head and neck, brain, and oligometastatic bone scans reported higher pre-scan anxiety, with coping difficulties most frequently reported by the head and neck group. Non-patient volunteers reported more physiological symptoms (e.g., sweating, nausea, dizziness) than patients, whereas patients undergoing head and neck and bone oligometastases scans were more reluctant to repeat the procedure. Most patients perceived MR Linac imaging as easier or comparable to diagnostic MRI, though 20 % of brain cancer patients found it more difficult. Conclusion: MR Linac imaging is generally well tolerated, though specific subgroups, particularly those requiring immobilisation, report greater anxiety and discomfort. These findings highlight the need for tailored strategies to improve patient experience, supporting wider implementation of MRIgRT.