What is a CT Myelography?
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 and nerve roots (the subarachnoid space) using a real-time form of x-ray called fluoroscopy.
In most cases, myelogram is followed by a computed tomography (CT) scan to better define the anatomy and any abnormalities.
What are common uses of a CT Myelography?
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 a herniation of the intervertebral disk between the successive vertebral bodies is compressing the 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 thickening of the adjacent ligaments.
Myelography can also be used to assess the following conditions when MR imaging cannot be performed, or in addition to MRI:
- tumors involving the bony spine, meninges, nerve roots or spinal cord
- infection involving the bony spine, intervertebral discs, meninges and surrounding soft tissues
- inflammation of the arachnoid membrane that covers the spinal cord
- spinal lesions caused by disease or trauma
A myelogram can show whether surgical treatment is promising in a given case and, if it is, can help in planning surgery.
How do I prepare for a CT Myelography?
If you have an iodine allergy or have had a reaction to contrast material in the past or are suffering from any kidney disease then you should notify our office when you are making the appointment, and also at the time of the scan, so that we can take additional precautions to avoid a problem.
If you are taking a diabetic medication called Glucophage, please alert us at the time of your appointment, as this medicine needs to be withheld for 2 days after you receive IV contrast material to avoid kidney problems.
Stop taking Aspirin and /or other blood thinners 5 days prior to this procedure.
Please inform our office and technologist if you know or think that you are pregnant.
You will be asked to lie on your side and after injecting numbing medicine in the back a small needle will be advanced into the spinal canal and small volume of contrast material will be injected. You will then be sent to the CT scan room.
During the CT scan, you will be asked to rest motionless on a padded table for 5 to 15 minutes depending on the area to be scanned. The table moves every few seconds as the images are obtained. You will hear faint humming and clicking sounds.
After the procedure you will be asked to take complete bed rest for 3 hours at Excel and for 24 hours at home to prevent post lumbar puncture headache. Please arrange for a driver to take you home