PROTON MAGNETIC-RESONANCE SPECTROSCOPIC IMAGING IN CHILDHOOD ATAXIA WITH DIFFUSE CENTRAL-NERVOUS-SYSTEM HYPOMYELINATION

The spatial distribution of metabolite signal intensities can be measu red within entire sections of the brain by proton magnetic resonance s pectroscopic imaging (H-1-MRSI). A group of six patients (4 unrelated girls and 2 brothers from 5 families) with childhood ataxia with diffu se CNS hypomyelination (CACH) underwent long-echo-time, single-slice H -1-MRSI. Relative to controls, there was a decrease in the signal inte nsity of N-acetylaspartate, choline, and creatine through out the whit e matter in all six patients. We identified lactate signals in white m atter in three of them with advanced disease. The degree of white matt er involvement was not homogeneous over the entire patient group, but did correlate with clinical presentation. Deep and posterior white mat ter tended to be more involved. There were no H-1-MRSI abnormalities i n the gray matter. H-1-MRSI findings suggest that this syndrome is sec ondary to a metabolic defect causing hypomyelination, axonal degenerat ion, and, in the most compromised cases, accumulation of lactate. This study shows that CACH is not limited to girls.