Correlation of spectroscopy and magnetization transfer imaging in the evaluation of demyelinating lesions and normal appearing white matter in multiple sclerosis

Abstract

Magnetization transfer imaging (MT) and localized proton spectroscopy (¹H‐MRS) were utilized in the evaluation of lesioins (high signal abnormalities on T₂‐weighted images) and normal‐appearing white matter (NAWM) in multiple sclerosis (MI). Eleven patients with a clinical diagnosis of MS were independently evaluated with both ¹H‐MRS and MT. The magnetization transfer ratio (MTR) of lesions was compared with the relative concentration of Kacetyl‐aspartate (NAA) and a composite peak at 2.1 to 2.6 ppm termed “marker peaks”. The MTR of white matter lesions in the MS patients was markedly decreased (6–34%; normal ≈︁42%), and correlated well with increase in the marker peaks region (0.94–3.89). There was no correlation between the relative concentration of NAA and MTR. Increased resonance peaks in the 2.1 to 2.6 ppm range and marked decreases in MTR may be a relatively specific indicators of demyelination.