Hypointense lesions on T1-weighted spin-echo magnetic resonance imaging - Relation to clinical characteristics in subgroups of patients with multiplesclerosis

Context: Hypointense lesions on T1-weighted spin-echo magnetic resonance im ages (T1 lesions) represent destructive multiple sclerosis (MS) lesions, co nsisting of axonal loss and matrix destruction. These lesions are being use d as a secondary outcome measure in phase III clinical trials. Clinical det erminants of T1 lesions may differ between subgroups of patients with MS an d subsequently may have implications for the selection of patients for clin ical trials. Objective: To determine if clinical characteristics of patients with MS are related to T1 lesion volume. Design: A survey of 138 patients with MS (52 with relapsing-remitting MS, 4 4 with secondary progressive MS, and 42 with primary progressive MS). Setting: The Magnetic Resonance Center for Multiple Sclerosis Research, Uni versity Hospital "Vrije Universiteit," Amsterdam, the Netherlands. Main Outcome Measures: Type of MS, Expanded Disability) Status Scale (EDSS) score, sex, age at first symptoms, and T1 lesion volume. Results: Patients with secondary progressive MS have the highest T1 lesion volume, patients with relapsing-remitting MS have a lower T1/T2 ratio than patients with secondary progressive MS and patients with primary progressiv e MS. In patients with relapsing-remitting MS and secondary progressive MS, T1 lesion volume relates to disease duration and EDSS score, while in pati ents with primary progressive MS sex is important. A trend toward higher T1 lesion volume was shown for male patients with primary progressive MS when compared with female patients with primary progressive MS (1.0 cm(3) vs 0. 3 cm(3), P=.03); a trend toward higher T1 lesion volume was found with age at onset in patients with relapsing-remitting MS and in patients with prima ry progressive MS. Conclusions: In patients with MS different clinical characteristics associa te with T1 lesion volume, suggesting a more destructive type of lesions in certain subgroups. A possible sex difference in (destructive) lesion develo pment on magnetic resonance imaging should be evaluated in more detail, pre ferably in a cohort.