Discography is used to see if the disc is the source of pain in patients with neck or back or pain. During discography, a dye is injected into the disc. The patient's response to the injection is observed. Pain that is similar to the patient's back or neck pain suggests that the disc might the source of the pain. Computed tomography (CT) is usually done after discography to look for actual changes in the disc.
The main reason to have a provocative discography is to find out if a patient with chronic back pain needs a spinal fusion. This is done in someone who has failed all efforts at conservative care. The results from discography are an important part of the preoperative evaluation for most patients. However what makes for a "positive" test isn't always clear.
A recent study at Stanford University showed provocative discography can't predict the future. Some patients with a positive discography never had any more episodes of back pain. Others with a negative discography developed back pain lasting as long as one year. This second group had other psychological problems.
Discography is just one of many tests used to help doctors and patients make decisions about back pain care and management.