However, the clinical presentation can vary significantly depending on the timing of the somatic mutation ranging from an isolated port-wine stain to complete Sturge-Weber syndrome.The characteristic port-wine stain, also called nevus flammeus, is caused by a capillary or venular malformation. It is present from birth while the extent and size of it is associated with the risk of leptomeningeal and ophthalmologic involvement. The greatest risk is associated with port-wine stains that appear to involve the entire V1 distribution followed by partial V1 involvement. There is ontroversy as to whether or not the distribution of port-wine stains truly follows trigeminal nerve branches per se. Port-wine stains are most often unilateral but can be bilateral. Typically, brain and eye involvement occur on the same side as the port-wine stain. Over time, port-wine stains can develop soft tissue or bone hypertrophy, proliferative nodules, and progressive ectasia which can lead to significant disfigurement.The two most common ocular manifestations include glaucoma and choroidal hemagioma. Glaucoma is estimated to occur in 30-70% with a bimodal peak occurring at the time of birth in 60% and between childhood and adolescence in 40%. The most frequent form of glaucoma is open-angle however closed-angle glaucoma may also occur. Congenital onset glaucoma is associated with other changes of the eye including megalocornea and buphthalmos. The choroidal hemangioma occurs in 40-50% of patients.
Kuvan or Kuvan Darya is a dry riverbed of what once was a tributary of the Syr river in Central Asia. The area is located west of Kzyl-Orda. It is an area of archaeological interest and was once home to tigers whose range extensed to the reedy shores of the Aral Sea. The area includes unusual kurgan burial sites. In the late 19th century there was some flow along the tributary before it petered out in marshlands. == References ==