MRI scans were obtained of the cervical section of the spinal cords of 30 patients with remitting multiple sclerosis. During the study period, patients received immunomodulatory agents (seven received interferon beta-1a, 13 received interferon beta-1b, and 10 received glatiramer acetate). Total focus volume in brain matter was assessed before and after treatment, along with the linear size of the spinal cord on sagittal sections at the level of the inferior margin of the body of C2. There was a significant (p = 0.002) reduction in focus volume in the group overall, from 10993 mm(3) (8098-13888 mm(3), p < 0.05; Me = 9336) to 5630 mm(3) (7400-3860 mm(3), p < 0.05, Me = 4180). There were also significant decreases in focus volume on the background of treatment with interferon beta-1b and glatiramer acetate (p = 0.026 and 0.027, respectively). Significant differences between groups were found in the magnitudes of increases in spinal cord atrophy: H (2, n = 30) = 8.06; p = 0.0178. Patients given glatiramer acetate showed a significantly smaller increase in atrophy as compared with those treated with interferon beta (p < 0.02).