Our patient has a very prominent chorioretinal anastomosis from an idiopathic ectopic disciform scar. It is best seen in the Optos color and green-channel images.
Learning Points:
Under normal conditions the retinal and choroidal circulations remain separate and distinct. Rarely, the two circulations directly connect with each other thru a chorioretinal anastomosis.
These can occur in chorioretinal scars (typically from inactive toxoplasmosis lesions), in macular telangiectasia, and in disciform scars. Laser photocoagulation can create an iatrogenic retinal venous-choroidal anastomosis to treat macular edema in non-ischemic CRVOs, although its use has not been widely adopted.
