One hundred patients with degenerative disease of the lumbar spine on whom both magnetic resonance (MR) and computed tomography (CT)-myelography were performed were reviewed. In one-third of the cases, the CT-myelogram provided additional useful information. This included definition of the extent of large disc herniations, demonstration of focal neural compression by small herniations, and clarifying abnormalities of the facets, including synovial cysts. These results should help to refine the indications for CT-myelography, which continues to be requested extensively.