Eye Signs of Systemic Disease: Case 5 Central Retinal Vein Occlusion

An 87-year-old woman complained of seeing a red tinge on the wallpaper in her house through her right eye. The patient had mild memory loss and moderate hypertension, for which she took atenolol(. She had quit smoking cigarettes many years earlier. Visual acuity in both eyes was 20/25. The patient had pseudophakia of the right eye from previous cataract surgery. A funduscopic examination of the eye revealed dilated and tortuous veins, flame-shaped hemorrhages, dot-blot hemorrhages, and retinal edema. No cotton-wool spots were present, and the macula was spared (A), which explained the good visual acuity in the right eye. A fluorescein( angiogram showed good perfusion, minimal capillary dropout, and no neovascularization. A nonischemic central retinal vein occlusion was diagnosed. It is thought that the underlying cause of central retinal vein occlusion may be compression of the vein by a thickened artery, which results in thrombus formation. The ability of both the artery and the vein to expand is limited, because their lumens narrow when they pass through the sieve-like lamina cribosa of the optic nerve head. The adjacency of the vessels leads to thrombus formation from turbulent blood flow. This condition typically develops in persons who are older than 50 years. Patients may have generalized arteriosclerotic disease and, often, associated diabetes, cardiovascular disease, hypertension, elevated cholesterol and triglyceride levels, temporal arteritis, and a history of smoking. Five weeks after the patient’s initial visit, her vision had deteriorated to 20/200 in the right eye. Funduscopic examination demonstrated macular edema and macular hemorrhages. The optic disc was significantly more congested than several weeks earlier. Signs of ischemia— such as cotton-wool spots and neovascularization—were absent (B). One month later (9 weeks after initial presentation), the patient’s vision had further deteriorated; she was able to count fingers at only 4 feet. More retinal and macular edema was present on fundus evaluation, and cotton-wool spots were seen (C). Significant retinal hemorrhaging and edema precluded the use of laser photocoagulation. A new surgical procedure—pars plana vitrectomy with radial optic neurotomy—was offered to the patient. In this operation, the vitreous is removed and a posterior radial stab incision is used to cut part of the optic nerve head, lamina cribosa, and scleral ring and the adjacent sclera. This “relaxes” or “decompresses” the confined channel through which the central retinal vein travels. A recent study found that visual acuity improved in 80% of patients who underwent radial optic neurotomy; it worsened in the remaining 20% of patients.¹In addition, 80% of participants experienced less optic disc congestion and more rapid intraretinal hemorrhage reabsorption than is expected in untreated patients.¹