Imaging of the thoracic aorta with time-resolved three-dimensional phase-contrast MRI: a review.

Time-resolved three-dimensional (3D) phase-contrast (PC) magnetic resonance imaging (MRI), or four-dimensional (4D) flow, is able to provide robust 3D images with three-directional velocities. This review discusses the technique and application of 4D flow in the imaging of thoracic aortic pathologies. It has been instrumental in describing normal flow patterns throughout the cardiac cycle in the ascending and descending aorta and has shown the variety of flow patterns that exist in ascending aortic aneurysms.