ABSTRACT
The oculoneurocutaneous syndromes (ONCS) are a group of disorders characterized by systemic hamartomas and/or choristomas of the eye, brain, skin, and sometimes the viscera.1-38 The term ‘phakomatoses’, previously used to designate these entities, is nonspecific and is used less often in the literature. As a result, we have chosen to group these entities under the rubric ONCS, which more accurately reflects their true nature. However, we realize that other terminology may be adopted in the future when the genetics of these conditions is better understood. The syndromes described include tuberous sclerosis complex (TSC), neurofibromatosis (NF), von Hippel-Lindau (VHL) syndrome, Sturge-Weber (SW) syndrome, WyburnMason (WM) syndrome, oculoneurocutaneous cavernous hemangiomatosis, and organoid nevus syndrome. This chapter covers these syndromes with emphasis on their ocular manifestations. The authors also discuss and illustrate the clinical and histopathologic features of these syndromes in more detail in recent textbooks.1-3
Genetics Most of the ONCS have an autosomal dominant (AD) mode of inheritance, often with incomplete penetrance. Specific chromosomal abnormalities are continually being recognized in association with these entities. Notable exceptions are SW, WM, and organoid nevus syndrome, in which heredity does not appear to play a role and genetic abnormalities are not yet clearly delineated.3
