Though contrast enhanced X-ray angiography provides high quality images of the coronary arteries, it is a highly invasive technique. It is therefore not suitable as a screening test for coronary artery disease. Neither is it used diagnostically until the patient is strongly suspected to have coronary artery disease. The tissue contrast achievable without contrast agents in MRI make it an excellent candidate for non-invasive coronary artery imaging. However, to accomplish such a task in MRI, the problem of imaging the entire volume of the heart in the presence of respiratory motion must be addressed. The research in this proposal will synthesize a fast 3D MR imaging sequence with a real-time motion compensation technique. An existing 3D stack-of-spirals trajectory sequence will be modified to include both the more efficient LR circuit model for K-space trajectory, and motion tracking to be used with the real-time compensation algorithm. The optimal respiratory motion tracking scheme for a clinical setting-will be computed and studied. The result will be a sequence robust enough to be used clinically. This sequence will be used in a clinical setting on patients with known coronary artery disease. The results will be compared with standard X-ray angiograms for corroboration of lesion location.
