Herpes Zoster (Shingles) //
A number of common viruses may affect both the skin and the eye. One of the more frequent disease entities that fit into this category is the chickenpox/herpes zoster (shingles) virus. Chickenpox has become a less frequently seen condition because of current vaccination practices. When it does occur, it is primarily a skin disease with only a small percentage of cases having inflammation of the cornea or iris (keratitis/iritis). The virus then goes into hiding near spinal and cranial nerve roots where it may remain quiet for one’s lifetime. On occasion, however, the virus may reactivate, multiply and then migrate to the skin or other areas (i.e., eye) along nerve fibers. Recurrence of dermatologic manifestations of this virus is termed herpes zoster or "shingles" and may occur in children and adults. When the eye or surrounding structures are affected during a recurrence, the disease is called zoster ophthalmicus.
Zoster ophthalmicus is often heralded by the onset of tingling and numbness over the scalp and forehead. Headache, malaise, fever and chills may also accompany the initial symptoms. Vesicles (blisters) erupt in small groups or occasionally large plaques that may cover the forehead, scalp and extend downward to the eyelids and nose. The acute inflammatory period lasts eight to fourteen days and then gradually quiets down leaving behind areas of redness, depigmentation and scarring. Persistent itching, burning or foreign body sensation, termed post herpetic neuralgia, occurs in approximately 10% of patients. Neuralgic pain and discomfort gradually diminishes, though 3% of this group of patients was found in to still have discomfort at the end of one year in one study.
Ocular manifestations can be seen during the acute phase when the rash is present or may be delayed by a number of weeks. Problems such as inflammation of the white of the eye (conjunctivitis), corneal involvement with roughness and clouding (keratitis) or inflammation of the iris and the surrounding tissues (iritis) can occur. While in many cases, these problems will resolve over a period of two to four weeks, there are some patients who will have a chronic course. This group of patients often requires long-term treatment with topical medications and is at some risk for visual loss.
Treatment of ocular herpes zoster ophthalmicus depends on the amount of time that has elapsed since the outbreak occurred and the extent of ocular involvement. Early treatment during the first couple of days has been shown to be beneficial to many patients. Treatment started after one or two weeks, however, is of uncertain value. Acyclovir or valcyclovir, oral antiviral agents, are the drugs most frequently used during the acute phase of the disease. Topical anti-inflammatory agents and dilating drops may also be used for some manifestations. Persistent inflammation may necessitate long-term treatment (months to years) in some patients.
Complications occur in a high percentage of patients with herpes zoster ophthalmicus. These may range from permanent scarring of the lids with alteration of the lid position to obstruction of the normal tear drainage system. Corneal scarring, vascularization, thinning and even perforation can occur. Chronic inflammation (iritis) within the eye is not uncommon. Inflammation of the white of the eye (scleritis), retinal inflammatory changes and even neurologic problems have been reported. Glaucoma may be seen in patients who have persistent intraocular inflammation.
Patients with herpes zoster ophthalmicus require regular ocular examinations as a means to monitor the activity of the disease. The herpes zoster virus is contagious to individuals who have not previously been vaccinated, contracted chickenpox or those individuals taking immunosuppresive agents.