The Retina Reference

Branch Retinal Artery Occlusion that Simulates a Cilioretinal Artery Occlusion

These are photographs from a patient who has a branch retinal artery occlusion. A - Red free photograph of the left fundus. The red arrow points to an embolus lodged at the bifurcation of the central retinal artery. This embolus blocks the blood flow to the small branch retinal artery indicated by the blue arrows. The retina supplied by this arteriole is white from ischemia. It has the location of a cilioretinal arteriolar occlusion, but in this case there is no cilioretinal arteriole. B - A frame from the mid-phase fluorescein angiogram. The blue arrow points to the occluded branch retinal artery and the yellow arrow to the branch venule draining the ischemic area. C - A frame from the late phase fluorescein angiogram shows that there is no leakage of fluorescein into the ischemic tissue (yellow oval). Late leakage is characteristic of vein occlusions, but is not seen in artery occlusions. The driving force is low in an artery occlusion for fluid to pass out of the vessel into the interstitium. D - False color map OCT shows thickening of the retina in the area of the occlusion. E - OCT line scan shows that the nerve fiber layer is thickened in the distribution of the arteriolar occlusion. The yellow arrow denotes the normal nerve fiber layer. The orange arrow denotes the thickened nerve fiber layer.