Isolated cranial nerve enhancement in metachromatic leukodystrophy.

Metachromatic leukodystrophy is a lysosomal storage disorder with an estimated incidence of 1:40,000. Magnetic resonance imaging at time of diagnosis often shows symmetric white matter involvement, sparing the arcuate fibers. A 25-month-old female child presented with a cranial neuropathy, a spastic gait, decreased leukocyte arylsulfatase-A activity, and elevated urinary sulfatides. Magnetic resonance imaging revealed multiple cranial nerve enhancement, without intraparenchymal white matter involvement.