We describe the MR findings of two cases of neurocutaneous melanosis (NCM) associated with inferior vermian hypoplasia (IVH).Materials and Methods
Two cases of NCM associated with IVH are presented. Both patients had congenital giant hairy nevi and multiple satellite lesions.Results
Magnetic resonance imaging revealed IVH as well as hyperintensities in the pons and the cerebellar leptomeninges on Tl-weighted images. The hyperintensities may be ascribed to the T1-shortening effect of melanin. A right parietal tumor in one patient and unilateral ventriculomegaly in another patient were also depicted.Conclusions
Magnetic resonance demonstration of the T1-shortening leptomeningeal infiltrations adds weight to the diagnosis of NCM. The implication of the concurrence of NCM and IVH is discussed.