PATTERNS OF BRAIN MAGNETIC-RESONANCE ABNORMALITIES ON T-2-WEIGHTED SPIN-ECHO IMAGES IN CLINICAL SUBGROUPS OF MULTIPLE-SCLEROSIS - A LARGE CROSS-SECTIONAL STUDY

To substantiate differences in magnetic resonance (MR) patterns in cli nical subgroups of multiple sclerosis (MS), we analyzed T-2-weighted M R images of a large regional population of MS patients (n = 188). The patients had already been classified according to recent consensus def initions regarding the clinical course of MS into relapsing-remitting (RR), secondary progressive (SP) or primary progressive (PP). Signific ant (p < 0.01; Spearman test) differences were present between RR and SP patients regarding total lesion load, size and location of lesions. RR and PP patients showed similar MR patterns. PP and SP patients dif fered in total lesion load, small and medium-sized lesions. The degree of atrophy was highest for SP patients. The clinical progression rate [Expanded Disability Status Scale (EDSS)/disease duration] was simila r for various subgroups; the MR progression rate (total lesion score/d isease duration) was significantly larger for SP than for PP patients. The lesions load disability quotient (total lesion load/EDSS) differe d between RR and PP patients and also between SP and PP patients. In S P patients, the total lesion load correlated significantly (Spearman r ank correlation coefficient of 0.52) with EDSS. We conclude that PP pa tients differ in MR abnormalities from SP patients, that PP and RR pat ients have similar MR abnormalities and that RR and SP patients are at a different end of the same spectrum of the disease. As the dynamics and clinical impact of MS lesions are different in the various clinica l subgroups, they should be considered separately in clinical trials.