Shunt Surgery for Neurocutaneous Melanosis with Hydrocephalus: Case Report and Review of the Literature.

BACKGROUND

Neurocutaneous melanosis is a rare phakomatosis characterized by large or multiple pigmented nevi and melanosis of the leptomeninges. It is often complicated by hydrocephalus due to melanotic deposits interfering with cerebrospinal fluid reabsorption in the basal cisterns or causing foraminal or aqueductal obstruction. In 10% of cases, it will be associated with the Dandy-Walker complex.

METHODS

We present the case of a 6-year-old girl with multiple congenital hairy nevi presenting with generalized tonic-clonic seizures, headache, and vomiting. Neuroimaging showed a communicating hydrocephalus associated with the Dandy-Walker variant, melanotic deposits in the amygdalae, thalami, and cortical sulci, and abnormal leptomeningeal enhancement. After undergoing ventriculoperitoneal shunt insertion, the symptoms of increased intracranial pressure abated. However, she again showed deterioration 1 month postoperatively due to progressive leptomeningeal spread suspicious for malignant degeneration.

CONCLUSIONS

The results of the present case and the findings from a review of related data suggest that shunt insertion (ventriculoperitoneal or cystoperitoneal) is an effective palliative measure for patients with neurocutaneous melanosis with associated hydrocephalus. Despite treatment, however, the prognosis of these patients remains poor owing to malignant progression and leptomeningeal spread of lesions, in particular, in cases associated with the Dandy-Walker complex.