A myelogram uses X-rays and a special dye called contrast material to make pictures of the
bones and the fluid-filled space (subarachnoid space) between the bones in your
spine (spinal canal). A myelogram may be done to find a tumor, an infection,
problems with the spine such as a
herniated disc, or narrowing of the spinal canal
The spinal canal holds the
spinal cord, spinal nerve roots, and the subarachnoid space.
During the test, a dye is put into
the subarachnoid space with a thin needle. The dye moves through the
space so the nerve roots and spinal cord can be seen more clearly.
Pictures may be taken before and after the dye is used. To get more information from the test, a
CT scan is often done after the X-rays, while the dye is still in your body.
Why It Is Done
A myelogram is done to check
- The cause of arm or leg numbness, weakness, or
- Narrowing of the spinal canal (spinal stenosis).
- A tumor or infection causing problems with the
spinal cord or nerve roots.
- A spinal disc that has ruptured
- Inflammation of the membrane that covers the brain and spinal cord.
- Problems with the blood
vessels to the spine.
A myelogram may help find the cause of pain that cannot be
found by other tests, such as an
MRI or a CT scan.
How To Prepare
Your doctor will tell you if you need to change how much you eat and drink before the myelogram. You may be asked to increase the amount of water you drink before the test. Follow the instructions exactly about eating and drinking, or your test may be canceled.
Before a myelogram, tell your doctor if you:
Arrange to have someone take you home and stay with you
after the test.
to your doctor about any concerns you have regarding the need for
the test, its risks, or how it will be done.
To help you understand the
importance of this test, fill out the
medical test information form(What is a PDF document?).
How It Is Done
The test is done by a doctor in
a radiology center or in the radiology department of a hospital.
You will need
to take off jewelry that might be in the way of the X-ray picture. You may need
to take off all or most of your clothes above the waist (you may be allowed to
keep on your underwear if it does not get in the way of the test). You will be
given a gown to wear during the test.