REVERSAL OF BLOOD-FLOW IN EXPERIMENTAL BRANCH RETINAL VEIN OCCLUSION

BACKGROUND AND OBJECTIVE: To demonstrate that the obstructed vascular lumen of the experimentally induced branch retinal vein occlusion (BRV O) induces retrograde blood flow, resulting in flow from the occluded vein to the feeder arterioles. MATERIALS AND METHODS: Photocoagulation was used to create occlusion of the branch retinal vein in a monkey m odel (n = 2; 1 cynomolgus, 1 rhesus). Twenty-four hours following phot ocoagulation, the eyes were examined for evidence of vascular occlusiv e disease. Vascular occlusion was proven by fluorescent vesicle angiog raphy with scanning laser ophthalmoscopy; these results were recorded to SVHS videotape. The images were then serially analyzed frame by fra me to track individual microsphere movement. RESULTS: The authors obse rved retrograde flow proximal to the point of vessel obstruction and e xtending backward into the arterial system. CONCLUSIONS: This demonstr ates the existence of retrograde flow in an experimental model of BRVO and might explain vascular complications seen in this disease process .