The phacomatoses

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