Factors affecting visual outcome in herpes zoster ophthalmicus: a prospective study

P>Purpose: To evaluate visual outcome and factors affecting visual outcome in herpes zoster ophthalmicus (HZO). Methods: A prospective, longitudinal, observational study was undertaken in 64 consecutive patients with HZO presenting within 72 h of rash onset. Patients underwent detailed ophthalmological and dermatological examinations at presentation, with follow up at first, second and fourth weeks and third and sixth months. All patients received both systemic and topical acyclovir. The main outcome measure was best-corrected visual acuity at 6 months' follow up. Local and systemic factors were correlated with visual outcome using univariate and multivariate analyses. Results: Overall visual outcome was good, with 36/64 (56.3%) patients having a visual acuity of 6/6 or better. Mild visual loss occurred in 22/64 (34.3%), moderate loss in 3/64 (4.7%) and severe loss in 3/64 (4.7%); moderate to severe visual loss was due to severe uveitis (2), neurotrophic keratitis (1) and cataract (3). Increasing age (P = 0.04), positive Hutchinson sign (P = 0.001), absent corneal sensation (P = 0.01), corneal epithelial lesions (P = 0.03) and uveitis (P < 0.001) were significantly associated with visual loss. Uveitis was found to be the best predictor of visual loss in HZO on multivariate analysis. Conclusion: The overall visual outcome is good in HZO patients receiving antiviral therapy. Hutchinson's sign and anterior uveitis were found to be strong predictors of visual loss in HZO. Presence of these predictors calls for close monitoring.