Herpes Zoster Ophthalmicus

Acute herpes zoster ophthalmicus of the right eye was diagnosed in a 70-year-old woman by her primary care physician, who prescribed oral acyclovir. After 1 week of therapy, the patient's eye became red and painful and she experienced photophobia and epiphora. She was referred for consultation.

Crusted lesions and skin erythema along the distribution of the ophthalmic, or first division of the trigeminal (fifth cranial), nerve were found. No active vesicular lesions were apparent.

Herpes zoster ophthalmicus accounts for 10% to 25% of all cases of herpes zoster. The eye may be involved in more than 70% of cases.¹ The risk of ocular involvement increases when lesions extend to the tip of the nose, as in this patient (Hutchinson sign). The nasociliary nerve, which innervates the tip of the nose, is the main sensory nerve to the eye, sending posterior ciliary nerves to that organ. If one portion of the nerve is infected with the virus, all the end organs it supplies will be affected as well. The incidence of ocular involvement is twice as high among patients with a Hutchinson sign compared with those with herpes zoster who do not have the sign (76% versus 34%); however, ocular manifestations do develop in one third of those without the sign.¹

A slit lamp examination confirmed that this patient had iritis. It has been said of such cases that “as the skin gets better, the eye gets worse.” As many as 60% of persons with herpes zoster ophthalmicus can have anterior uveitis. Typically, it arises within 2 weeks of the onset of the rash. Iris atrophy may result, and corneal stromal keratitis or corneal edema may be associated with the uveitis.

The uveitis of herpes zoster ophthalmicus often is a smoldering, low-grade process that lasts for months or years. In severe cases, posterior synechiae, glaucoma, and cataracts can develop.

Therapy includes a topical corticosteroid (eg, 1% prednisolone acetate) and a topical cycloplegic, such as 2% or 5% homatropine. When the cornea is involved, prescribe preservative-free artificial tears to be used several times a day for symptomatic relief and erythromycin ophthalmic ointment to prevent secondary infection.

Other anterior segment signs of herpes zoster ophthalmicus include lid retraction secondary to scarring, paralytic ptosis, follicular conjunctivitis, episcleritis, and scleritis. Posterior segment signs of the infection are hemorrhagic retinitis, acute retinal necrosis, choroiditis, papillitis, and retrobulbar optic neuritis. The extraocular muscles also can be affected from either a partial or a complete third, fourth, or sixth cranial nerve palsy

REFERENCE:1. Kaufman HE, Barron BA, McDonald MB, Kaufman SC, eds. Companion Handbook to the Cornea. 2nd ed. Boston: Butterworth-Heinemann; 2000:207-232.