A Myelogram is an x-ray study of the spinal cord, or, more specifically, the spinal canal which houses the various nerves which make up the spinal cord. Generally your doctor will order a myelogram when he or she suspects some physical deformity or problem is pushing into the spinal canal and putting pressure on the spinal cord. A myelogram can be of the neck (a cervical myelogram), upper back (a thoracic myelogram), or the lower back (a lumbar myelogram). They can also be of two types, a gas myelogram (not a common exam) or anopaque myelogram. The difference between the two lies in the type of contrast medium used (needless to say, nerves do not show up on x-rays otherwise). A gas myelogram uses a gaseous contrast medium that will show up on x-rays as a black area, while opaque myelograms generally use a water soluble contrast medium similar in every way to that used in IVP's and angiograms.

When you report for your myelogram, the technologist will show you to a dressing room and ask you to change into a hospital gown. You will then be escorted to the x-ray room where your exam will be performed. You will be asked to lie on your stomach on the table, often with a small cushion or pillow under your stomach. The radiologist who will be doing your study with the technologist's assistance will then use betadine, or some other cleaning agent to clean a small area over your lower back. He or she will then inject that area with a numbing agent such as lidocaine. The radiologist will then do a spinal, or lumbar puncture to allow the injection of the contrast medium. If your doctor has requested it, the radiologist may also at this point draw off a small amount of the fluid around the spine for analysis in the lab. This fluid is called Cerebral-Spinal Fluid, and is a popular spot for certain nasty germs that, thankfully, are becoming fairly rare here in the United States from all that I have been told. The radiologist will then inject the contrast medium into the spinal canal while watching it go in under fluoro (short for fluoroscopy). If a lumbar myelogram is being done, the radiologist will the proceed to take several films using fluoro while keeping you flat, or possible tilting the table slightly feet down. If a thoracic or cervical myelogram is what your doctor has ordered, the table will be tilted head down until the radiologist has determined that the contrast has reached the proper area. Do not worry about sliding off the table though, as a set of straps will have been placed around your ankles prior to the exam starting to prevent just that sort of thing from occurring.

Once the radiologist has seen everything he or she needs to under fluoro, the technologist will take two to three regular x-rays to finish the exam. You will then be placed on a hospital bed or stretcher, and taken to a holding area where a nurse will watch over you for two to four hours with your head raised to 30 or 45 degrees. The reason for this is that the contrast medium can cause severe but temporary headache if enough of it gets into the skull. Fortunately the newer water soluble contrast mediums currently in use are absorbed into the blood stream and eliminated from the body by the kidneys, so it is no longer necessary to admit the patient over night as it used be back in the sixties and early seventies. Still, it would be a good idea to take it easy the rest of the day even after you have been discharged.

The most common question I hear about myelograms is "I have had back surgery. Will you still be able to do the spinal puncture?" The answer is probably yes. Even after a surgeon has fused two or more disks in the back, the radiologist can normally find a place under fluoro where the spinal needle can be safely inserted. If surgery or physical impairment make it impossible to do a spinal puncture in the lower back however, there are alternatives. The most common alternative is to do the spinal puncture in the neck, or cervical, region. This method does entail a bit more risk than doing a spinal puncture in the lower back, but if both your doctor and the radiologist agree that a myelogram is necessary, it can be done. If this method is used, you must not move your head for any reason unless directed to do so by the radiologist. If you can do this, your exam can proceed without any great risk. If you cannot, tell the radiologist so before the exam begins. There are things we can do to insure that your head will not move, but the radiologist will not know to use them if you do not tell him that you cannot hold your head still.

[Home] [X-ray] [Cat Scan] [MRI] [Mammography] [Sign Guestbook] [Take Survey] [Bio]