Myelography Health Article

Results

A normal myelogram shows a spinal canal of normal width, with no areas of constriction or obstruction.

A myelogram may reveal a herniated disk, tumor, bone spurs, or narrowing of the spinal canal (spinal stenosis).

Health care team roles

Myelograms can be performed in a hospital x-ray department or in an outpatient radiology facility. The test is performed by a radiologist with the help of a radiologic technologist. The radiologist will interpret the results of the test and recommend any further treatment. A nurse may assist during the procedure, may prepare the patient before the procedure, or may monitor the patient afterwards.

Historical note on contrast media used for myelography

Until the mid- to late 1970s, myelography was performed using an non-aqueous, oil-based, contrast medium. Use of this medium created a significant problem, since it had to be removed from the intrathecal space after the procedure (since it was non-aqueous, it would not be absorbed). More often than not, the removal process caused significant pain for the patient because, after the physician moved the bolus of contrast material to where the needle was, he/she would attach a syringe and attempt to suck the oily fluid out. The negative pressure in the intrathecal space often pulled on the nerve roots in the vicinity of the needle, causing shooting pains and electrical shock-like sensations that extended down to the patients' legs. In many instances, it was not possible to remove all of the contrast material.

In the 1970s, a non-ionic aqueous (water soluble) contrast agent, suitable for injection into the intrathecal space was developed. Its development and adoption for myelography, eliminated the pain and suffering associated with removal because, like contrast agents injected intravenously, it was absorbed and eventually excreted after the procedure.

KEY TERMS

Contrast agent—Also called a contrast medium, this is usually a barium or iodine dye that is injected into the area under investigation. The dye makes the interior body parts more visible on an x-ray film.

BOOKS

Daffner, Richard. Clinical Radiology, The Essentials. 2nd ed. Baltimore: Williams and Wilkins, 1999.

Pagana, Kathleen, and Timothy Pagana. Mosby's Diagnostic and Laboratory Test Reference. St. Louis, MO: Mosby-Year Book, 1998.

Torres, Lillian. Basic Medical Techniques and Patient Care in Imaging Technology. 5th ed. Philadelphia: Lippincott, 1997.

ORGANIZATIONS

The Spine Center. 1911 Arch St., Philadelphia, PA 19103. (215) 665-8300. <http://thespinecenter.org>.