Angiomatosis (Encephalofacial; Sturge-Weber Disease): This is a developmental disorder that involves a capillary-venous angioma of the face and leptomeninges of the brain. The facial angioma is also called a nevus flammeus or "port wine stain". Most lesions are unilateral. Although the angioma is present at birth, the neurological manifestations of the disorder emerge over the course of development. They may include focal seizures, contralateral spastic hemiplegia, hemisensory loss and visual field defects. There may be cortical atrophy and calcifications.