Discography
This technique is used to diagnose discogenic pain, pain generated from the intervertebral disc. This technique is properly termed "provocation" or "provocative" discography as the disc is stimulated in an attempt to reproduce clinical pain. This study attempts to reproduce internal disc pressures, similar to pressures generated in painful activities, in order to diagnose disc pain. A normal disc accepts the injection of contrast without pain, usually maintains a high internal pressure with the injection, and demonstrates no leak of contrast from the central portion of the disc. The injection of an abnormal disc will cause pain similar to the patient's symptoms at a relatively low internal pressure, and may demonstrate an abnormal pattern of contrast spread. Therefore, your spine surgeon may request discography. When performed correctly and according to protocol, provocative discography can generate information about pain physiology as well as internal disc anatomy. After the needles are in position, the patient is asked to describe the sensation experienced with each injection. Each needle is injected with contrast while internal disc pressures are measured. The pattern of contrast spread is observed and recorded, and the patient's perception of pain is documented. Discography is not used to improve pain symptoms directly. It is used to identify the pain generating disc so future therapies may be planned accordingly.
