Definition of Radionuclide cisternogram:

A radionuclide cisternogram is a nuclear scan test used to diagnose spinal fluid circulation problems.

How the test is performed:

A lumbar puncture (spinal tap) is done first. Small amounts of radioactive material, called a radioisotope, are injected into the fluid in the lower spine.

You will be scanned 4 - 6 hours after receiving this injection. A special camera takes images that show how the radioactive materials travel with the cerebrospinal fluid through the spine and if the fluid leaks outside the spine.

You will be scanned again 24 hours after injection, and possibly at 48 and 72 hours after injection.

How to prepare for the test:

No preparation is usually necessary. However, if you are very anxious or agitated, sedation may be necessary. You must sign a consent form. You will wear a hospital gown to make the spine more accessible. Remove jewelry or metallic objects before the scan.

How the test will feel:

During lumbar puncture, the lower back over the spine is numbed with an anesthetic. However, many people find lumbar puncture somewhat uncomfortable, usually because of the pressure on the spine during insertion of the needle.

The scan is painless, although the table may be cold or hard. No discomfort is produced by the radioisotope or the scanner.

Why the test is performed:

The test is performed to detect problems with spinal fluid circulation and spinal fluid leaks.