Polymorphous presentations in vitelliform macular dystrophy: subretinal neovascularisation and central choroidal atrophy.

Two dominantly inherited macular dystrophies demonstrate the difficulty in establishing a diagnosis based on the fundus appearance. In 1 family the propositus presented with unilateral retinal haemorrhage associated with subretinal choroidal neovascularisation which remained unilateral over an 8-year period. In the other family the propositus presented with bilateral central choroidal atrophy. All affected family members had an abnormal electro-oculogram and a normal electroretinogram, suggesting the diagnosis of vitelliform macular dystrophy. Since vitelliform macular dystrophy has a wide range of expressivity, with polymorphous appearances of the fundus, the diagnosis is best made by the presence of a dominant mode of inheritance and an abnormal electro-oculogram.