ESTRO 2025 - Abstract Book

S3069

Physics - Image acquisition and processing

ESTRO 2025

Conclusion: DR was the most reliable method for tracking lung tumour motion in cine-MR images, compared with SIFT and RR. This will be the method of choice when analysing images in the ongoing prospective clinical trial.

Keywords: SBRT, 2D-cine MRI, Tumour respiratory motion

3915

Digital Poster Prospective clinical trial (NCT06322329) evaluating lung tumour motion with 2D cine MRI: pilot study results Elias Lindbäck 1,2 , Kristin Karlsson 1,2 , Torsten Dorniok 1 , Karin Lindberg 2,3 , Kenneth Wikström 4,5 , Nils Olovsson 5,6 , Mattias Hedman 2,7 , Elisabeth Myrvold Roth 7 , Daniel Alm 7 , Mirjam Forsgren Bäckström 7 , Giovanna Gagliardi 7 , Eva Onjukka 1,2 1 Department of Nuclear Medicine and Medical Physics, Karolinska University Hospital, Stockholm, Sweden. 2 Department of Ocology Pathology, Karolinska Institute, Stockholm, Sweden. 3 Department of Head, Neck, Lung and Skin Tumors, Karolinska University Hospital, Stockholm, Sweden. 4 Medical Radiation Physics, Uppsala University Hospital, Uppsala, Sweden. 5 Department of Immunology,, Genetics and Pathology, Uppsala University, Uppsala, Sweden. 6 The Skandion Clinic, The Skandion Clinic, Uppsala, Sweden. 7 Department of Radiation Oncology, Karolinska University Hospital, Stockholm, Sweden Purpose/Objective: In lung SBRT, time-resolved CT (4D-CT) is the standard method for evaluating tumour motion through the respiratory cycle. However, 4D-CT is limited by short tumour-specific acquisition time and a relatively low temporal resolution. The measured tumour motion can be non-representative when relying on 4D-CT [1, 2]. Unlike 4D-CT, dynamic MRI could be performed with high temporal resolution (about 5 images per second) and over a longer