Contributor: Gordon K. Klintworth
The choroid is a common site for a hemangioma. This benign vascular hamartoma may involve the choroid diffusely or be a localized circumscribed lesion. The localized choroidal hemangioma is a solitary, hamartoma that involves only a small part of the choroid. It is not part of a systemic disorder and vascular congestion may enlarge the hemangioma slightly over years. A diffuse choroidal hemangioma is often associated with a hemangioma of the brain, orbit or periocular skin (nevus flammeus) as part of the Sturge-Weber syndrome. Both the circumscribed and diffuse choroidal hemangioma contain capillaries and cavernous blood vessels. The circumscribed hemangioma consists predominantly of cavernous blood vessels and is virtually always a component of the Sturge-Weber syndrome. Visual symptoms result from an exudative retinal detachment [retinal detachment - exudative] caused by the accumulation of a subretinal exudate. Macular detachment can cause central visual loss. In the Sturge-Weber syndrome glaucoma can follow iris neovascularization [neovascularization - iris] and angle closure [glaucoma - neovascular] or the elevated venous pressure associated with the episcleral and orbital vascular changes.