Physicians often rely on clinical experience to judge situations like these. Patient history and clinical presentation help them sort out the symptoms and the possible cause. However, without further imaging studies there’s no way to know for sure. Sometimes it’s hard to differentiate between pain from the disc versus scar tissue even with X-rays, MRIs, and other diagnostic tests.
Two advanced diagnostic tests may help. The first is the discography or pain provocation test. In this test a needle is guided by a special X-ray device into the disc. A small amount of dye is injected into the disc. If the disc is the source of pain, the pressure from the extra fluid will reproduce the patient’s symptoms.
The second test is a gadolinium (Gd) contrast magnetic resonance imaging. Gd is a useful contrast agent when doing MRIs. It provides greater contrast between normal and abnormal tissue compared to other dyes injected during the MRI procedure. Gd in abnormal cells causes the cells to become very bright and easier to see.
There are a few disadvantages to the Gd-MRI. Gd doesn’t show why the cells are abnormal (e.g., scar tissue versus tumor cells). The patient may have a small reaction to the use of the dye. Headaches, nausea, and skin burning at the site of the injection have been reported.