Development of a markerless approach to abdominal motion tracking during radiotherapy: an observation-only feasibility study

This study evaluates a new method to track tumour and organ motion during radiotherapy. Using artificial intelligence, a customised 'motion model' will be created for each participant using their CT images. Depending on the participant’s standard of care treatment, this may involve the collection of 2 additional cone beam computed tomography (CBCT) images for model generation purposes. The model will be loaded into a research software by a Medical Physicist trained in the use of the software. The research software will be run at the time of treatment to measure the motion of critical structures such as the tumour, pancreas, duodenum, small bowel and/or stomach. X-ray imaging acquired as part of this study will act as inputs to the research software. Note that this is an observation-only study; the output of the research software will not be used to modify the participants' treatment. In the future, it is expected that the radiotherapy treatment team will use a software such as this to better direct the radiation towards the tumour and away from nearby organs based on the motion observed. Participants will undergo additional x-ray imaging during their radiotherapy treatment sessions. This is to 1) enable to use of the research software and 2) to monitor the position of certain organs, to verify the output of each participant's motion model. Organs will be monitored if they are within 2 cm of the treatment area. This additional imaging will be acquired during 5 of the participants' standard treatment sessions, and is expected to extend the length of each treatment session by no more than 10 minutes. It is anticipated that trial data collection will be complete within a 2 week period.