Branch Retinal Vein Occlusion with Retinal Neovascularization After Branch Retinal Artery Occlusion

These photographs belong to a 71 year old woman who had hypertension and an 80 pack year smoking history. She had sudden, painless, superior and central visual field loss of the left eye and was found to have an inferior hemicentral retinal artery occlusion (top left panel). Note the embolus in the artery (black arrow). The inferior hemimacula shows ischemic whitening and a large cotton wool spot (flesh arrow). There is a separated area of retinal ischemia superior to the disc (blue arrow) suggesting that there were several separate emboli. The superior temporal branch retinal vein is unobstructed (note the normal venous diameter at the green arrow). Three months later (top right panel) she has developed a nonischemic branch retinal vein occlusion superotemporally. The thrombus is at the arteriovenous crossing on the superior edge of the disc. Note that downstream of the thrombus, the branch vein is narrowed (green arrow). Note the dot hemorrhages (gray arrows). There are two tufts of neovascularization. The one at the blue arrow arises from a branch retinal artery. The one at the yellow arrow arises from a branch retinal vein. The bottom left panel shows the late fluorescein angiogram at the time of the artery occlusion. The bottom right panel shows the late angiogram after the nonischemic branch vein occlusion. Note the good capillary perfusion, yet the new vessels leak (yellow arrows). This is a rare instance of retinal new vessels following a nonischemic branch retinal vein occlusion. Possibly VEGF arising from the ischemic retina affected by the branch retinal artery occlusion was enough to cause new vessel growth in the distribution of the nonischemic branch vein occlusion.