Objective: To assess the long-term predictive value of quantitative lesion load measurement on brain MRIs in patients after a 10-year follow-up who presented initially with a clinically isolated syndrome of the optic nerve, brainstem, or spinal cord.
Background: Quantitative MRI measurement is being used in treatment trials as a surrogate marker in MS, but there is a lack of long-term MRI follow-up data in assessing the natural course of the disease from the earliest stages.
Methods: Using a semiautomated threshold technique, the total lesion volume (TLV), the course of the disease, and disability were assessed in 58 patients at onset and after 5 and 10 years.
Results: The TLV at presentation correlated significantly (r = 0.81, p = 0.0001) with the TLV and also with the Expanded Disability Status Scale (EDSS) score (r = 0.45, p = 0.001) at 10-year follow-up. In contrast there was no correlation of the TLV at 5 years with subsequent change in EDSS score over the next 5 years (r = 0.18, p = 0.12). The change in TLV over the first 5 years in patients who developed clinically definite MS (CDMS) differed significantly according to the type of disease course (relapsing-remitting with disability, secondary progressive, or benign) manifesting at 10-year follow-up.
Conclusion: Quantification of changes detected by T2-weighted brain MRI at the earliest clinical stages is strongly predictive of the subsequent development of CDMS as well as the clinical course and level of disability 10 years later.