The clinical stratification of facial port-wine stains provides a guide to patient counselling and therapeutic interventions. Port-wine stains affecting the entire V1 distribution predict strongly for underlying neurological and/or ocular disorders that require on-going ophthalmological surveillance and/or neurological management. Although the classical Sturge-Weber syndrome encompasses a triad of clinical manifestations, incomplete forms are not uncommon. This neuro-oculo-cutaneous syndrome is believed to be a result of vascular malformations of associated structures derived from the neuroectoderm (facial skin, eye, and parieto-occipital region of the brain and leptomeninges) during the first trimester. However, the pathogenesis of port-wine stains and Sturge-Weber syndrome remains unclear.