Test Details & Preparation
Magnetic resonance imaging (MRI) of the lumbar spine is a safe and painless test that uses a magnetic field and radio waves to produce detailed pictures of the lumbar spine (the bones, disks, and other structures in the lower back).
During the examination, radio waves manipulate the magnetic positions of the atoms of the body, which are picked up by a powerful antenna and sent to a computer. The computer performs millions of calculations used to create cross-sectional, black and white images of the body. These images can be reconstructed into three-dimensional pictures of the scanned area. This helps to pinpoint problems in the lumbar spine when the scan focuses on that area.
MRI can detect a variety of conditions of the lumbar spine, including problems with the bones (vertebrae), soft tissues (such as the spinal cord), nerves, and disks.
An MRI sometimes is performed to assess the anatomy of the lumbar spine, to help plan surgery on the spine, or to monitor changes in the spine after an operation.
MRI of the lumbar spine can be useful in evaluating symptoms such as lower back pain, leg pain, numbness, tingling or weakness, or problems with bladder and bowel control. It can also help to diagnose tumours, bleeding, swelling, developmental or structural abnormalities, and infections or inflammatory conditions in the vertebrae or surrounding tissues.
A lumbar spine MRI usually doesn't require any special preparation. However, the technician will have you remove any objects containing metal (such as eyeglasses and jewellery) because they can produce a bright or blank spot on the diagnostic film (but braces and dental fillings won't interfere with the scan).
The MRI images will be looked at by a radiologist who's specially trained in interpreting the scans. The radiologist will send a report to your doctor, who will discuss the results with you and explain what they mean. In most cases, results can't be given directly to the patient or family at the time of the test.
MRIs are safe and easy. No health risks have been associated with the magnetic field or low-energy radio waves that are used for the test. The procedure can be repeated without side effects.