Magnetic resonance imaging (MRI) is a noninvasive medical test that helps physicians diagnose and treat medical conditions.

MR imaging uses a powerful magnetic field, radio frequency pulses and a computer to produce detailed pictures of organs, soft tissues, bone and virtually all other internal body structures. The images can then be examined on a computer monitor, printed or copied to CD. MRI does not use ionizing radiation (x-rays).

Detailed MR images allow physicians to better evaluate various parts of the body and certain diseases that may not be assessed adequately with other imaging methods such as x-ray, ultrasound or computed tomography (also called CT or CAT scanning).

MR imaging is usually the best choice for examining the:

• body's major joints.
• spine for disk disease.
• soft tissues of the extremities (muscles and bones).

MR imaging is typically performed to diagnose or evaluate:

• degenerative joint disorders such as arthritis and meniscus tears (knee).
• fractures (in selected patients).
• joint abnormalities due to trauma (tendon tears for example).
• spinal disk abnormalities (herniated disk for example).
• the integrity of the spinal cord after trauma.
• sports-related injuries and work-related disorders caused by repeated strain, vibration or forceful impact.
• infections (osteomyelitis for example).
• tumors (primary tumors and metastases for example) involving bones and joints.
• pain, swelling or bleeding in the tissues in and around the joints and bones.