MRI of disseminated developmental dysmyelination in fukuyama type of CMD

Whether the pathologic origin of white matter lesions in Fukuyama type of c ongenital muscular dystrophy (FCMD) is delayed myelination or dysmyelinatio n is a controversial issue. This study investigated pathologic distribution in white matter with heavily T-2-weighted images using fluid-attenuated in version recovery (FLAIR) pulse sequence. For detection of abnormal white ma tter lesions, FLAIR images were approximately twice as sensitive as T-2-wei ghted images and five times as sensitive as T-1-weighted images of spin ech o sequence. The distribution of the white matter lesions was disseminated a nd not correlated with cortical disarrangement, The distribution was not co nsistent with delayed myelination, These findings support the evidence foun d using in vitro proton-NMR spectroscopy that the pathologic origin of whit e matter lesions is dysmyelination, When conventional magnetic resonance im aging is used, masked white matter lesions are easy to misidentify as delay ed myelination instead of disseminated developmental dysmyelination. The le sions in the white matter of FCMD are masked because of brain development. (C) 2000 by Elsevier Science Inc. All rights reserved.