The phacomatoses.

The phacomatoses are disorders characterized by multiple hamartomas of the central and peripheral nervous system, eye, skin, and viscera. Many of these diseases have well-defined Mendelian patterns of inheritance because of a mutation of a single gene. In other instances, no clear patterns of inheritance or genetic susceptibility have been identified. In some cases, patients are at increased risk of malignancy. The combination of ocular and CNS manifestations seen in patients with the phacomatoses makes neuro-ophthalmologic evaluation particularly important in the diagnosis and management of these patients.