Postoperative magnetic resonance imaging in patients with cervical myelopathy.

Magnetic resonance imaging using T1-weighted sagittal images was performed on 81 postoperative patients with cervical myelopathy. Cord compression was observed after surgery in 32 (40%) of the patients. Compression was demonstrated in the decompressed area in 9 patients, at the upper or lower edge of decompression in 11 patients, and at adjacent levels of fusion in 11 patients. The remaining patient had cord compression in both the decompressed area and at the adjacent level. From their operative results, cord compression was proved to be functionally innocuous in 13 (41%) patients and the cause of neurologic deterioration in 3 (9%); it was not clear whether or not the compression was innocuous in the remaining 16 (50%) patients.