A discogram is an x-ray procedure to evaluate the intervertebral disc and to determine if your pain or other symptoms are specifically related to an abnormality of the disc. Disks are cushion-like pads made up of cartilage and a jelly-like substance. They act as shock absorbers between the bones in the spine. The intervertebral disc is a structure that is located between the spinal vertebrae. This procedure works by attempting to cause a pain similar to that you experience regularly. Each suspect disk is tested in turn. If the test duplicates your usual pain, the disk under examination is considered to be the source of the problem.
Franklin Moser, MD, Chief of Interventional Neuroradiology, heads our team of imaging physicians, nurses and technologists who specialize in these procedures.
A needle is placed into the nucleus pulposus of an intervertebral disc and a small
amount of iodinated contrast is injected. The radiologist will localize the site for
needle placement using fluoroscopic guidance. In addition to the pain control
administered by an anesthesiologist, the radiologist will administer local anesthesia
at the site of needle placement. Since the needle tip is in a location near the nerve
roots, you may briefly experience symptoms such as pain or an electric shock
sensation down your leg. A small amount of iodinated contrast agent is injected
into the disc. At the time of the injection, you will be asked if the injection repro-
duces your pain or other symptoms. A series of radiographs are obtained after
the injection to evaluate the condition of the disc. In most cases multiple disc
levels are injected. Pain and discomfort at the time of the injection are common
since one of the goals of this test is to determine if your symptoms are coming
from irritation or compression of nerve roots by the disc. The pain may be as bad
as the worst pain your back or spine trouble usually gives you. This pain generally
subsides to your baseline level following the injection. You are conscious in light
sleep during the procedure and can ask questions at any time. After the needle is
removed, a CT scan is performed to provide further information. Occasionally, needle
placement must be made from the midline with the needle crossing the sac that
contains the nerve roots. In that instance, you may experience a headache after
the procedure. If this approach is required, you will have to be observed in the
hospital for several hours after the needle placement.
