T1 lesion load and cerebral atrophy as a marker for clinical progression in patients with multiple sclerosis

We investigated the relationship between local tissue destruction, diffuse cerebral atrophy and clinical progression in patients with established multiple sclerosis (MS). Twenty-nine patients with MS (13 patients with relapsing--remitting and 16 with secondary progressive disease) were included in a prospective serial study. Cerebral volumes, T1 hypointense lesion volumes, T2 hyperintense lesion volumes at baseline and at 18 months follow-up, and the volume of monthly enhancing lesions from month 0 to month 9 were assessed on magnetic resonance imaging (MRI) brain scans using highly reproducible semi-automated quantitative techniques. The main outcome measures were the MRI parameters and disability on Kurtzkes' Expanded Disability Status Scale. There was a significant correlation between the change (increase) in T1 lesion volume and progressive cerebral atrophy, whereas no correlation between the T2 lesion volume and atrophy was seen over the same follow-up period. The change in T1 lesion volume correlated more strongly than did T2 lesion volume change with the change in disability. We conclude that hypointense abnormalities detected in T1-weighted brain scans and cerebral atrophy may be directly linked. Although one should bear in mind some potential for reversibility due to inflammatory, oedematous lesions, these MR measures are a useful marker of progressive tissue damage and clinical progression in established MS.