A myelogram is a special kind of test which utilizes X-rays and a special dye. The test helps to view the pictures of the bone structure as well as the sub arachnoid space, which is the fluid filled space between the bones of the spine. The myelogram test is specifically used on the spine to check the presence of tumors or infections in the spinal column. This test may also be conducted to find out other problems of the spine, like a herniated disc or arthritis which may have caused the spinal canal to become narrow.
The spinal canal is a sensitive area of the body. It holds the spinal nerve roots and the fluid in the subarachnoid space, which acts as a shock absorber and cushions the column, preventing it from getting damaged. The dye used in this test is inserted into the spinal column with a thin needle. This dye is allowed to move through the subarachnoid space, highlighting the nerve roots and the spinal chord as it moves along. The pictures of the spinal column are taken before the insertion of the dye and after the insertion of the dye. In a lot of cases, a CT scan is also done immediately after the X-rays are done. The CT scan is done immediately before the dye escapes the body so that a better look can be had at the spinal column.
A myelogram test is specifically done to check for pain, numbness, or weakness in the limbs, inflammation of the arachnoid membrane, herniated or ruptured disc, narrowing of the spinal canal, suppression of the blood vessels which carry blood to the spine and the brain, and presence of infection or cancerous growth in the nerve roots or the spinal column. Though both the MRI and the CT scan are also powerful tests, they are often unable to find the exact cause of the pain. A specific myelogram, like a cervical myelogram, can help diagnose the exact cause of pain or discomfort.
To prepare for the myelogram procedure, you should not eat or drink anything for 4-8 hours before the test. Your doctor or technician will issue specific instructions regarding this. If you suffer from epilepsy or seizures, you should talk to your doctor. Also inform your doctor if you have allergic reactions to any chemicals or if you have asthma. If you are pregnant, it is a good idea to tell your doctor before hand.