Recognition of lumbar disc disease with magnetic resonance imaging.

Ten normal adult volunteers, 75 patients with low back pain and/or lumbar radiculopathy, 16 patients following chymopapain treatment, 14 patients with recurrent symptoms following disc surgery, and two patients with distal cord compression were scanned on Fonar 3000 permanent magnet scanner. Of all the patients 98 had additional computed tomography scans (CT) of the lumbar spine and 82 had myelography. Lumbar magnetic resonance imaging (MRI) and CT scans were both diagnostic in cases of herniated and extruded discs. MRI scan showed more information concerning the degenerative state of the intervertebral discs. It was relatively more accurate in detecting, small bulging and herniated discs without ruptured anulus and the relation of the migrated fragments of extruded discs to both the back of the vertebrae and the thecal sac. Moreover, lumbar MRI matched the clinical response of disc disease to chymopapain treatment more than lumbar CT scan. In addition, the MRI studies differentiated more accurately postoperative epidural fibrotic changes from recurrent herniated and/or extruded disc and detected distal spinal cord abnormalities. CT scan easily detected laterally herniated lumbar discs. Myelography was the diagnostic study in cases of arachnoiditis.