Herpes simplex virus (human herpesvirus 1 and 2) and herpes varicella-zoster virus can cause acute outer retinal necrosis, resulting in photophobia, ocular pain, floaters, and decreased visual acuity. Ophthalmic findings include panuveitis, vitritis, retinal arteritis, ONH edema, and a necrotizing retinitis that initially spares the posterior pole. See BCSC Section 9, Uveitis and Ocular Inflammation.
The most common neurologic manifestation of herpes infection is CNS encephalitis (Fig 14-20). Radiculitis may occur, producing Ramsay Hunt syndrome (see Chapter 11) and herpes zoster ophthalmicus (HZO). Neuro-ophthalmic complications of HZO include ischemic optic neuropathy, optic neuritis, and ocular motor CN palsy. In the majority of cases, HZO-induced ophthalmoplegia occurs within 2 weeks of onset of the HZO rash. Treatment with oral antiviral therapy and oral corticosteroids is usually recommended. This self-limiting ophthalmoplegia improves over the course of several months; the majority of patients recover from the diplopia, at least in primary gaze.
Excerpted from BCSC 2020-2021 series: Section 5 - Neuro-Ophthalmology. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.