[Recurrent postoperative sciatica. Prospective evaluation of magnetic resonance imaging and x-ray computed tomography with iodine injection].

The respective performance of MRI and CT were studied prospectively in 80 cases. Surgery was indicated in 56 patients after MRI examination and 21 patients after CT; the 21 patients were included in the 56. Among these patients, 45 were reoperated and 11 preferred the medical treatment. Surgery confirmed the diagnosis for 44 patients (from the 45), and the only discordance was the presence of ligament calcification, associated to a disc protrusion not seen on MRI. Surgery confirmed also the diagnosis for the 21 cases diagnosed by CT after iodine injection. However, among the 24 cases of fibrosis diagnosed by CT after i.v. injection were found: 19 recurrent disc protrusions, 4 disc protrusions with fibrosis, and 1 disc protrusion at a level above the operated disc.