Realtime organ motion tracking and fast image registration system for MRI guided surgery

We developed a realtime organ motion tracking/image registration system embedded in a 1.5 clinical MR scanner to track a target organ in realtime in MRI guided therapy. The displacement of the target organ is measured by projection profile matching, based on navigator echo technique. The phantom and volunteer studies showed that the system can provide the information of respiratory motion of the liver with frame rate of up to 10 Hz, delay of 200 ms and error of 2.0 mm, and the system was feasible in clinical use. (author)