PURPOSE: To evaluate the MR appearance of multiple sclerosis in the spinal cord. MATERIALS AND METHODS: Between January 1990 and December 1996, we retrospectively analyzed 27 spinal MR images of 18 patients in whom-onthe basis of Poser's diagnostic critera-multiple sclerosis of the spinal cord had been diagnosed. Eleven patientswere men and seven were women, and they were aged between 18 and 58(mean, 37) years. Using T1-weightedsagittal(n=27), T2-weighted axial(n=26) and sagittal(n=27), and contrast enhanced T1-weighted(n=14) images,lesions were analyzed for multiplicity, location, length, cross-sectional area and location, cord size, andenhancement pattern. Brain MR images(n=15) were also evaluated. RESULTS: In 14 of 18 patients, a solitary lesionwas seen on initial MR imaging. Four of the 14 had double lesions, and on follow-up MR imaging at 2_5 months, fivewere seen to have double lesions. Eleven lesions were found in the cervical cord, and 12 in the thoracic cord, twowere in the cervicothoracic and two in the thoracolumbar region. The length of 12 lesions was less than twovertebral heights, while 15 extended for more than two vertebral heights. Six lesions occupied less than 50% ofthe cross-sectional area of the cord and the other 20 occupied more than 50% of this area. Cord size was enlargedin 17 cases, unchanged in eight, and atrophic in two. Eight lesions in 14 patients who underwent enhanced MRimaging showed focal contrast enhancement; there was patchy enhacement in two, nodular enhancement in two, andlinear enhancement in four. Among 15 MR images of the brain, high-signal intensity lesions, compatible withmultiple sclerosis, were demonstrated in seven cases. CONCLUSIONS: Multiple sclerosis plaques in the spinal cordfrequently extend for more than two vertebral body heights of either the cervical or thoracic level, occupy morethan 50% of the cross-sectional area and manifest as enlarged cord. But the MR imaging findings, however, arenonspecific. Abnormalities were seen in approximately 50% of MR images of the brain.