MRI
MRI (magnetic resonance imaging) is a diagnostic imaging procedure that combines a powerful magnetic field, radio waves and computer technology to provide detailed images of tissues, muscles, nerves and bones. Because MRI scans use magnetic force and radio waves to create images, there is no radiation exposure like with X-rays during the procedure. MRI scans can be done with or without a contrast agent or material. MRIs are often used instead of CT to study soft tissues or organs because bones do not obscure the organs and soft tissues as they do with CT imaging.
Radiologists can use MRI scans to assess everything from ruptured discs in the spine to detecting brain tumors and vascular diseases through techniques such as:
- Breast MRI can be a more effective imaging technique than mammography for some women, and can provide additional details for diagnosing and evaluating breast abnormalities.
- Spectroscopy (MRS) assesses chemical abnormalities in the brain for conditions such as coma, Alzheimer's disease, stroke, brain tumors, head injury and MS.
- Angiography (MRA) evaluates blood flow, or detects brain aneurysms or blood vessel abnormalities. It is used to visualize renal, carotid and vertebral arteries, or examine the aorta for aneurysm.
- Perfusion and diffusion MRI scanning examines blood flow through tissues to evaluate strokes.