4D-MRI Sequence for Radiotherapy Application
Abdominal motion imaging is challenging due to breathing artifacts. A widely used technique for organ motion management in radiotherapy (RT) is 4D-CT. It consists of acquiring a breathing signal thanks to an external surrogate at the same time as repeated acquisitions of images and the sorting of the images according to the respiratory cycle obtained from the breathing signal. However, CT scans present poor contrast for soft tissue, such that the lesions are difficult to observe even when a contrast agent is used.