MRI stands for magnetic resonance imaging.  As with ultrasounds, no radiation is given with this test.  A powerful magnet is used to align the atomic nuclei in the body, typically focusing on water and fat content in the various tissues.  Like a CT scan, the MRI is typically used to provide detailed images of the abdominal and pelvic organs and structures. Also like a CT scan, it can also be used to evaluate a variety of disease states and complaints; however, the images take longer to obtain and the test is administered in a long tube. Patients with claustrophobia, need to discuss this with the doctor before the test is scheduled.