Interferon beta-1b and intravenous methylprednisolone promote lesion recovery in multiple sclerosis

Objective: To determine whether lesion evolution in relapsing-remitting mul tiple sclerosis (RRMS) patients is altered by treatment with interferon bet a -1b (IFN beta -1b) or by intravenous methylprednisolone (IVMP) as measure d by magnetization transfer imaging Methods: Magnetization transfer ratios (MTR) of 225 contrast enhancing lesions (CEL), in four RRMS patients were s erially determined for 12 months before and 12-18 months after contrast enh ancement in a baseline vs treatment trial with IFN beta -1b. During the bas eline period 185 new CEL were identified: 76 were treated with IVMP (1 g/da y x 5 days) and designated steroid CEL (S-CEL); the remaining 109 were cons idered baseline lesions (B-CEL). During IFN beta -1b treatment, 40 CEL (IFN -CEL) were identified. After image co-registration, regions of interest (RO Is) defining new CEL were transferred to the MTR image set to determine the mean lesion MTR on each monthly exam. The lesion MTR was compared to MTR o f normal appearing white matter (NAWM) on the some exam. Results: As early os IZ months prior to enhancement the MTR of CEL was reduced compared to NA WM (mean 9.43 +/- 3.2%; P< 0.001). The further reduction in MTR (28% <plus/ minus> 4.0) at the time of contrast enhancement was not significantly diffe rent for B-CEL S-CEL or IFN-CEL Following enhancement lesion recovery for I FN-CEL (P=0.02) and S-CEL (P=0.002) was significantly higher than B-CEL Con clusion: IFN beta -1b and IVMP reduce tissue damage and promote lesion reco very in RRMS patients. The additional benefit of IVMP compared to IFN beta -1b may be related to its inhibitory effect on demyelination.