This patient presented with these asymptomatic, unilateral, peripheral, large, outer retinal hemorrhages.
The patient was later diagnosed with a 100% internal carotid artery occlusion. Carotid surgery was not recommended, but we are monitoring the patient due to the risk for anterior or posterior segment neovascularization.
Learning Points:
The retinal hemorrhages in ocular ischemic syndrome (OIS) are somewhat unique. Retinal vascular disorders like diabetic retinopathy, retinal vein occlusions, and hypertensive retinopathy usually have flame- and dot-shaped inner retinal hemorrhages concentrated around the posterior pole.
Our patient’s findings are classic for OIS, with hemorrhages in the deeper peripheral retina. The retinal periphery is literally the end of the line for the retinal arterial circulation. In an eye receiving less blood supply due to carotid occlusive disease, the more proximal retina has first dibs on the available oxygen. There are penetrating capillaries that dive radially from the nerve fiber and ganglion cell layers into the deeper retina. The deep vascular complex that supplies the inner and outer plexiform layers is thus furthest downstream, and these endothelial cells are likely damaged in OIS. Blood cells leaking into this space accumulate, causing the large outer blot to hemorrhage.
These patients need to have a carotid Doppler and ultrasound and be referred for medical or surgical intervention if they have a critical stenosis. They may also develop anterior or posterior segment neovascularization requiring photocoagulation and/or anti-VEGF injections. Iris neovascularization can develop, leading to neovascular glaucoma. Hypotony can also occur.
