A 19-year-old woman with a history of leukemia in remission after bone marrow transplant presented with a 2-week history of photophobia and decreased vision in the left eye. The right eye was normal. Vision in the affected left eye was 20/32 without an afferent pupillary defect and an intraocular pressure of 9 mm Hg. Anterior segment examination revealed mild cell and flare and moderate vitritis. Scattered retinal hemorrhages and circumferential retinal pallor were observed on fundus examination. Fluorescein angiography (Figure) revealed marked peripheral vascular occlusion, papillitis, and posterior vascular leakage in acute retinal necrosis due to herpes zoster virus. She was treated with intravitreous ganciclovir and intravenous acyclovir. Systemic prednisone was administered 3 days later, and she recovered. Final visual acuity at 6 months was 20/25 OS.