myelogramA myelogram is an x-ray exam of the spaces in the spinal cord which contain various nerves. This test uses a special dye (contrast material), which mixes with the spinal fluid. Myelograms are useful for those who cannot have MRIs, including patients with pacemakers and cochlear implants.

Myelograms are helpful in determining if there is pressure on the spinal nerves. The dye that is injected shows the bones and spinal fluid. If there is something pushing into the nerves, the dye would show an indentation in the spinal sac. Pressure could be caused by a herniated or bulging disc, lesions, tumors, or injury to the spinal nerve roots.