Magnetic resonance imaging (MRI) uses a large magnet, radiofrequencies, and a computer to make detailed pictures of organs and structures within the body. It is used to diagnose health problems.

Magnetic resonance imaging (MRI) is a test that uses a large magnet, radio signals, and a computer to make images of organs and tissue in the body. In this case, the heart is imaged. MRI may be used instead of a CT scan when organs or soft tissues are being studied.

Magnetic resonance imaging (MRI) uses a large magnet, radiofrequencies, and a computer to make detailed images of organs and structures within the body, in this case, the brain and spine. MRI is used to help diagnose a health problem.

A mammogram is a way to look at your breast using X-rays. It is used to find and diagnose breast disease in women. Read on to learn more details about when and why to get a mammogram, and what you can expect when having it done.

A mastectomy is surgery to remove a breast. It is part of treatment for breast cancer. Here's what you need to know about this procedure.

A mediastinoscopy is a procedure used to examine the mediastinum. This is the space behind the breastbone (sternum). Read on to learn more about the procedure, and what to expect.

A muscle biopsy involves removing a small piece of tissue to diagnose disease. The tissue is usually removed using a needle.

A myelogram is a diagnostic imaging test generally done by a radiologist. It uses a contrast dye and X-rays or computed tomography to look for problems in the spinal canal. Problems can develop in the spinal cord, nerve roots, and other tissues. This test is also called myelography.