CONGENITAL MUSCULAR-DYSTROPHY, WHITE-MATTER ABNORMALITIES, AND NEURONAL MIGRATION DISORDERS - THE EXPANDING CONCEPT

The congenital muscular dystrophies are a heterogeneous, recessively i nherited group of disorders that have been subclassified on the basis of clinical central nervous system involvement. We report two children with ''pure'' congenital muscular dystrophy, one merosin negative and one merosin positive with extensive white matter and occipital cortic al neuromigration abnormalities on magnetic resonance imaging (MRI). T he first patient (merosin-negative congenital muscular dystrophy) pres ented with hypotonia and weakness in the neonatal period and subsequen tly was found to have a leukoencephalopathy and occipital cortical dys plasia on magnetic resonance imaging. The second patient presented wit h developmental delay without definite weakness. Initial investigation s revealed a leukoencephalopathy and cortical dysplasia, but the patie nt subsequently was shown to have merosin-positive congenital muscular dystrophy. These patients illustrate that white-matter changes are no t specific for merosin-negative congenital muscular dystrophy alone an d that extensive cortical abnormality can be found in both groups of p atients. In addition, our second patient illustrates a nonmuscular mod e of congenital muscular dystrophy presentation that should be conside red in patients with a ''nonprogressive leukodystrophy.''