Herpes zoster ophthalmicus (HZO), or shingles, typically occurs in older adults and may affect the eyes, manifesting as ptosis, lid scarring, ectropion, entropion, scleritis, corneal atrophy or inflammation of the optic nerve, retina or choroid, potentially leading to permanent vision loss. Age, race and immune status are known risk factors for reactivation of the latent varicella zoster virus, but a recent study identified risk factors specifically for HZO-related vision loss. In addition to age and immune status, it found that uveitis plays a role.

The retrospective cohort study included 869 subjects with HZO, of which 84.8% were diagnosed with ocular involvement at or within the first month of presentation. Patients had a mean follow-up time of 6.3 years.

The researchers found that the most common forms of ocular involvement were conjunctivitis (76.1%), keratitis (51.2%) and uveitis (47.6%). They noted moderate vision loss (≤20/50) secondary to HZO in 9.6% of eyes and severe vision loss (≤20/200) in 3.6%. “Causes of vision loss included corneal scarring (94%), corneal perforation (4.8%) and secondary glaucoma (1.2%),” they wrote in their paper. Severe vision loss secondary to HZO was significantly linked to older age, immunosuppression, poor visual acuity on presentation and uveitis.

The researchers concluded that approximately one in 10 individuals may develop moderate or severe vision loss, primarily due to corneal scarring. Severe permanent vision loss was linked to uveitis, immunosuppression and older age.