What is Myelogram?
Myelography is an imaging examination that involves the introduction of a spinal needle into the spinal canal and the injection of contrast material in the space around the spinal cord (the subarachnoid space) and nerve roots using a real-time form of x-ray called fluoroscopy or CT Scan.
An x-ray (radiograph) is a noninvasive medical test that helps physicians diagnose and treat medical conditions. Imaging with x-rays involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.
When the contrast material is injected into the subarachnoid space, the radiologist is able to view and evaluate the status of the spinal cord, nerve roots, and meninges, which are the membranes which surround and cover the spinal cord and nerve roots. Myelography provides a very detailed picture (myelogram) of the spinal cord and spinal column. The radiologist views the passage of contrast material in real-time within the subarachnoid space as it is flowing using fluoroscopy but also may take permanent images, called x-rays or radiographs, of the contrast material around the spinal cord and nerve roots in order to document abnormalities involving or affecting these structures. In most cases, the myelogram is followed by a computed tomography (CT) scan to better define the anatomy and any abnormalities.
Myelography is most commonly used to detect abnormalities affecting the spinal cord, the spinal canal, the spinal nerve roots and the blood vessels that supply the spinal cord, including:
to show whether herniations of the material between the vertebral bodies, termed the intervertebral disks, are pushing on nerve roots or the spinal cord.
to depict a condition that often accompanies degeneration of the bones and soft tissues surrounding the spinal canal, termed spinal stenosis. In this condition, the spinal canal narrows as the surrounding tissues enlarge due to the development of bony spurs (osteophytes) and the adjacent ligaments.