Patients with an acute zonal occult outer retinopathy-like illness rapidly improve with valacyclovir treatment.

<bold>Purpose: </bold>To describe 3 cases of an acute zonal occult outer retinopathy-like illness responsive to valacyclovir hydrochloride.<bold>Design: </bold>Retrospective, interventional case series.<bold>Methods: </bold>Three patients were treated with valacyclovir and monitored by clinical examination, Goldmann visual field testing, and electroretinography.<bold>Results: </bold>Patients with an acute zonal occult outer retinopathy-like illness presented following progressive vision loss. This course was immediately reversed by treatment with oral valacyclovir, and visual acuity and visual field improved significantly at 1 week and 1 month. Patients remained stable without treatment during a follow-up period ranging from 1 to 3 years.<bold>Conclusions: </bold>Some conditions with features of acute zonal occult outer retinopathy may be attributable to a subacute herpetic viral infection that is responsive to oral antiviral medication. [ABSTRACT FROM AUTHOR]