When new blood vessels originating from the choroid appear to arise spontaneously, without a known cause, the condition is referred to as idiopathic choroidal neovascularization. The new blood vessels may proliferate beneath the retina’s pigment epithelial layer, causing type 1 neovascularization. They may penetrate the pigment epithelial layer and occupy the sub-retinal space beneath the sensory retina, causing type 2 neovascularization. Regardless of underlying causes and locations of growth, neovascularization results in vision loss. Unlike age-related macular degeneration, age is irrelevant to the cause of this condition.