SIGNIFICANCE: Acute retinal necrosis is a rare, sight-threatening condition typically found in immunocompromised patients and is most commonly caused by varicella zoster virus. Because of the poor prognosis and rapid progression of the disease course, prompt antiviral management is paramount. PURPOSE: A case report of acute retinal necrosis in a patient with herpes virus infection after a cervical epidural corticosteroid injection was performed. Extensive laboratory work and frequent follow-ups are necessary for management. This case report outlines the clinical signs of acute retinal necrosis and discusses the appropriate referrals and treatment needed to improve prognosis.CASE REPORT: A 63-year-old man presented to our eye clinic with symptoms of pain and light sensitivity. Examination revealed anterior uveitis, vitritis, optic disc edema, macular edema, vasculitis, and retinitis of the left eye. The serum antibody test results showed abnormal ranges for varicella zoster virus and herpes simplex virus type 1, and the patient was diagnosed with acute retinal necrosis. Treatment prescribed by a retina specialist included oral valacyclovir and later oral prednisolone, for which the patient responded well before developing the common complication of retinal detachment. CONCLUSIONS:The progressive nature of acute retinal necrosis is usually debilitating to vision, even when managed properly. Because prognosis is often poor, it is important to make proper diagnoses combined with a complete review of the patient's medical history and immune status to prevent further vision loss.