Correlation of magnetic resonance imaging parameters with clinical disability in multiple sclerosis: a preliminary study

Magnetic resonance imaging (MRI) is frequently used to monitor new treatmen ts in multiple sclerosis (MS), but its role is limited by the uncertain rel ationship between MRI parameters and clinical disability. A brain MRI study using nine MRI parameters was undertaken in 15 MS patients with a wide spe ctrum of disability to evaluate the relationship between each parameter and disability. A strong correlation was found between disability (measured us ing Kurtzke's EDSS) and total lesion load on both proton density (PD; r = 0 .79) and T1 (r = 0.71) weighted sequences. There was also a strong correlat ion of disability with average lesion magnetisation transfer ratio (MTR; r = -0.74) and calculated T1 (r = 0.71) but not with calculated T2 or the ave rage signal intensity of lesions on the conventional T1-weighted, PD-weight ed and heavily T2-weighted images. Thus, four parameters which measured eit her the extent of lesions (PD lesion load) or their pathological severity ( MTR, calculated T1, hypointense T1-lesion load) were correlated significant ly with disability. While this suggests that such parameters will be useful in treatment trial monitoring, further multi-parameter MRI studies, of lar ger cohorts and using a wider range of techniques, are indicated.