If your physician suggests a procedure called discography as a means of treating your pain, some commonly asked questions are listed and answered below.
What is discography?
Discography is the study of the condition of the discs of the spinal column. A discogram is a picture of the disc and is often the only way to show a tear in the disc and demonstrate the exact cause of a patient’s pain symptoms. Many patients with chronic low back pain, whom have had a normal or non-diagnostic MRI scan of the low back may be candidates for a discogram.
How is discography performed?
Discography is a surgical procedure performed according to the recommendations by the North American Spinal Society in a sterile environment using x-ray guidance.
The patient will first change into a hospital gown and an intravenous (IV) catheter will be inserted into the arm. The IV is through which antibiotics, pain medication, and sedation medication will be delivered to the patient.
The patient is then placed on a special x-ray table in an operating room or procedure room. The target areas are then sterilized with a Betadine solution, or if the patient is allergic to iodine, it is sterilized with Hibiclens and draped with a sterile covering. The skin and underlying tissue are then anesthetized with Xylocaine or other numbing medication.
The approach is typically from the patient’s right side of the low back. The position for performing the procedure utilizes anatomical landmarks which are initially verified with a fluoroscope.
Utilizing the fluoroscope or C-arm imagery intensifying camera, a needle is inserted through the skin into various lumbar discs in the back.
Once the needle has been placed into the disc and the location is verified on the x-ray machine, a small amount of contrast media or dye is placed in the disc. The amount is usually between 0.25 – 0.5 milliliters which is about a thimble-full of liquid. If a tear is present within a disc, the liquid will leak out of the disc and into the surrounding areas. The leakage will be visible on the x-ray.
While the liquid is being injected, the patient is asked what they are feeling. Injecting into a normal disc may cause some discomfort to the patient but it is a different discomfort than what the patient’s typical pain is. If the disc being injected is the patient’s source of pain, it should exactly reproduce the pain sensation for which the patient originally came to seek help.
Several discs are tested in order to locate normal and abnormal discs. Typically, 3 different levels of discs are tested, although the exact number may increase or decrease as considered appropriate by the physician performing the test. The patient is sedated but awake during the procedure and is constantly asked questions about what they are feeling. The patient is in control and the test can be stopped at any time.
After several discs have been injected with contrast material or dye, x-rays are taken to document the entire procedure. In addition, the procedure may be videotaped. Careful documentation of the procedure is recorded by a nurse and the physician. The entire procedure typically takes 20 – 40 minutes. After the test, the patient is taken off the x-ray table and taken to a post discography CT study (CAT scan) to verify if there are further complications that were not seen with the discogram. This scan will interpreted by the radiologists and the results sent to the physician who performed the discogram.
How is discography interpreted?
A number of factors are considered which may include:
1. The amount of fluid that can be injected into the disc.
2. Whether an injection into a particular disc reproduces the same pain that brings you to see a physician.
3. The appearance of the disc on the subsequent x-ray pictures.
4. Once the doctor has the results of your discogram, he/she will look at all of the information gathered.
5. These factors are interpreted and recommendations will be discussed extensively with the patient.
What is a disc?
The disc is an oval-shaped soft structure that cushions and separates adjacent bony vertebra (each spinal bone). It has a firm outer rim called an annulus fibrosis and a jelly-like center portion called a nucleus pulposus.
What is an annular tear of the disc?
This means a tear in the outer portion of the disc. This condition is often caused by trauma and cannot be seen on an MRI scan. An annular tear in the disc can cause chronic low back pain and/or lower extremity pain. These tears often never heal.
What is degenerative disc disease?
This is a broad, non-specific term that describes the breakdown of spinal discs which can result from defects with which one is born and may dispose a person to developmental problems. It may also result from trauma, repeated spine injuries, smoking, and the aging process to some degree. The breakdown can cause narrowing of the disc spaces, abnormal spine movements, and possible spinal nerve compression, all of which can result in low back pain.
What are the significant potential risks associated with discography?
Soreness and increased low back spasms are common with this procedure. Fortunately, these effects usually pass within a few days. Pain medications and muscle relaxants will be prescribed to ease the side effects.
The chief concern is the possibility of an infection or inflammation of the disc, which would then require subsequent treatment. Whenever any instrument (such as needles, probes, or any other surgical tool) is put into your body, there is a possibility of injury to adjacent structures or nerve tissue.
Allergic reactions to dye or radiopaque substances can occur. Any history of previous allergy to iodine-containing substance or shellfish should be brought to the attention of the staff before this test. It is possible that the test may be inconclusive or that unforeseen complications may occur, however, serious complications are rarely seen.
What are my other options?
The study is an elective diagnostic test. Other options include doing nothing or continuing with conservative therapy which may include exercising, physical therapy, bracing, lumbar traction, and/or pain management drug therapy.
I have been scheduled for a discography. Now what?
First, you will need to plan to bring a designated driver to escort you home after the discogram.
Do not eat or drink anything 4 hours prior to the procedure. This includes gum, water, smoking and hard candy. Also, make sure to bring all necessary insurance information for registration.
Please check-in 30 minutes prior to your scheduled discogram time at the facility where you are scheduled. If you are running late, or need to cancel your appointment, please notify the office.
How long is the test?
Time is directly related to the number of discs to be studied. With this in mind, the study usually takes less than 1 hour. After the study, you will then remain in the special procedure area for 30 more minutes for observation.