Indocyanine green angiography of a laser-induced retinal-choroidal venous anastomosis

A patient with a central retinal vein occlusion and cystoid macular edema whose visual acuity was 20/200 was treated with heavy argon laser photocoagulation to a peripheral retinal vein. The patient's visual acuity improved to 20/20. An indocyanine green angiogram performed 5 months following laser therapy showed that a retinal-choroidal venous anastomosis had formed at a point where a large retinal vein crossed over a large choroidal vein. Because indocyanine green angiography can locate large choroidal veins, it may be helpful in guiding this laser treatment.