Differentiation of dys- and demyelination using diffusional anisotropy

We attempted differential diagnosis of dysmyelination and demyelination in childhood using magnetic resonance diffusion weighted imaging, Pelizaeus-Merzbacher disease, one of the dysmyelination disorders, demonstrated diffuse high intensity of the cerebral white matter on T-2-weighted images, which demonstrated diffusional anisotropy on diffusion weighted images, On the other hand, high intensity lesions on T-2-weighted images in Krabbe disease, one of the demyelination disorders, lost diffusional anisotropy. Another demyelination disorder, Alexander disease-related disorder, also lost its diffusional anisotropy, In contrast to relatively high signal of the lesions on diffusion-weighted images in Krabbe disease (high signal type), the lesions in Alexander disease-related disorder showed low signal on diffusion-weighted images (low signal type), These results suggest that diffusion-weighted images will be clinically useful to differentiate dysmyelination from demyelination; both of them demonstrate similar high intensity lesions of the white matter on T-2-weighted images. (C) 1997 by Elsevier Science Inc.