[Vascular anastomoses at the posterior pole of the eye (author's transl)]

Anastomoses between vessels of the fundus may occur as congenital malformations or secondary to vascular diseases affecting the eye. Congenital anastomoses can be of the racemose hemangioma type, with severe malformation of the retinal vessels, ocular complications, and neurologic manifestations, or as simple A-V shunts with visual impairment but limited tendency to show other ocular or neurologic involvement. These anastomoses must be distinguished from other vascular malformations like telangiectasis (Leber, Coats) or the angiomatous lesions of von Hippel's disease. Secondary anastomoses may be confined to the retinal vessels or involve chorioretinal connections. Retinal anastomoses occur in vascular disorders like retinal vein occlusions, diabetes, periphlebitis and hemoglobinopathies. They are often amenable to treatment by light coagulation. Chorioretinal anastomoses occur whenever Bruch's membrane is destroyed by traumatic, inflammatory, degenerative or physical (light coagulation) influences. Light coagulation may be the appropriate treatment, although complications are not rare.