Sickle cell trait affects 8% of African Americans, and 0.4% of African Americans have sickle cell (HbSS) disease. Approximately 0.2% have hemoglobin SC (HbSC) disease. Intravascular sickling results in hemostasis and thrombosis.

OCULAR MANIFESTATIONS of sickle cell disease include

• focal obstruction to blood flow in the conjunctival vessels (“comma sign”)
• sector iris atrophy and cataract (from anterior segment ischemia)
• iris neovascularization (due to retinal ischemia or detachment)
• peripheral retinal neovascularization
• pathologic enlargement of the foveal avascular zone
• subretinal hemorrhages (“salmon patch”) that may clear with associated RPE hyperplasia (“sunburst sign”) or hemosiderin deposition (“iridescent spot”)
• “comma-shaped” vessels on the optic nerve head
• retinal artery occlusion (branch and central) due to sickle cell–induced obstruction of blood flow in the retinal vasculature
• optic atrophy associated with anterior ischemic optic neuropathy or retinal artery occlusion
• vitreous hemorrhage associated with retinal neovascularization and/or retinal tear formation.

Retinal neovascularization is most often seen in patients with SC disease, whereas systemic complications are more frequent with SS disease.

COMPLICATIONS OF OCULAR SURGERY: Anterior segment ischemia is a well-described complication of retinal surgery in individuals with sickle cell disease. However, the precipitating surgery usually involves placement of an encircling band, significant intraocular pressure elevation, or some other mechanical disruption of ciliary blood flow. We describe a unique case of a patient with hemoglobin SC disease who had anterior segment ischemia after a pars plana vitrectomy without scleral buckling surgery for a repair of a traction-rhegmatogenous retinal detachment. We suspect that peripheral panretinal photocoagulation contributed to the development of anterior segment ischemia in this case.

TREATMENT OF ANTERIOR SEGMENT ISCHEMIA: Treatment of anterior segment ischemia in patients with sickle cell disease includes face-mask O2, a specially designed eye mask for delivery of O2 directly to the corneal surface, and systemic as well as topical steroids to reduce the destructive complications of intraocular inflammation. In addition, reestablishment of the blood-ocular barrier might help reverse the hypotony that can be associated with anterior segment ischemia. Although exchange transfusion is no longer done routinely in patientswith SC undergoing ocular surgery, it was used in this case to optimize oxygen delivery to the anterior segment.