Technical Principles of MRA

In this chapter we discuss the basic principles underlying magnetic resonance angiography (MRA) and the specific boundary conditions that apply to the different vascular beds. Unlike X-ray angiography, MRA does not expose the patient to potentially harmful ionizing radiation nor does it require iodinated contrast. In addition, it has the potential to noninvasively visualize the vessel wall, atherosclerotic plaque, and thrombus, thereby providing new insights into the process and stage of atherosclerotic disease. MRA is primarily based on blood flow and can be divided into “bright blood” and “black blood” methods depending on whether blood appears “bright” or “black” on the MR images.