Quantitative MRI changes in gadolinium-DTPA enhancement after high-dose intravenous methylprednisolone in multiple sclerosis.

In 12 patients with definite multiple sclerosis who received a total of 21 courses of high-dose (1 gram daily for 10 consecutive days) intravenous methylprednisolone, we performed MRI of the brain with and without gadolinium-DTPA before and after treatment. On the initial MRI, there was a total of 98 enhancing lesions, 93 of which were also represented on the unenhanced images. After treatment, 13 patients improved clinically, and 78 of the lesions lost enhancement but remained visible on the unenhanced images. There were six new enhancing lesions on the second MRI. Thus, the blood-brain-barrier integrity improved after high-dose IV methylprednisolone, which correlated well with the clinical improvement. The lesions remaining visible on the unenhanced images indicate an incomplete histologic recovery at the time of the second scan, and also demonstrate that unenhanced MRI alone is not sufficient to monitor disease activity in the short term in multiple sclerosis.