Herpes and the Eye
When we think of herpes we typically think of the venereal disease or cold sores. Many people are not aware that chicken pox and shingles are also caused by a form of the herpes virus, or that it is the leading infectious cause of blindness in the United States.
Herpes affecting the eye is called ocular herpes and is caused by the Type 1 herpes simplex virus. About 400,000 Americans have some form of ocular herpes, and there are about 50,000 cases diagnosed every year.
Causes of Ocular Herpes
Herpes is transmitted through bodily fluids. It enters the eye either by contact with another person who has an outbreak, or through contact with a part of your own body where there is an outbreak, and then touching your eye.
Nearly everyone is exposed to the virus during childhood. When it enters the body it travels to the nerves and may be dormant for a long time. It may never give you an outbreak.
The symptoms of an initial outbreak may be mild enough that it goes undetected. Once an initial outbreak does occur, there is about a 50 percent chance it will recur. The virus can be reactivated by sunlight, heat, fever, stress, hormonal changes, certain medications, dental or surgical procedures, or trauma. There is no set timeframe for a recurrence. It could be weeks or years.
Ocular Herpes Symptoms
Ocular herpes affects the eyelids, conjunctiva, and cornea. It can result in ongoing eye infections which scar the cornea and in some cases the scarring leads to blindness. Symptoms of ocular herpes can include:
- Light sensitivity
- Recurring infections
- Decreased vision
Types of Ocular Herpes
There is a wide range of severity among cases of ocular herpes. Many cases are a simple infection which can be cleared up quickly but when the infection gets more deeply into the corneal layers it can cause blindness.
- Herpes keratitis is infection of the cornea’s top layer, the epithelium. It is the most common form of ocular herpes and typically leaves no scars.
- Stromal keratitis is infection of the cornea’s middle layer, the stroma. This type of ocular herpes can cause scarring, reduced vision and sometimes blindness.
- Iridocyclitis is infection of the iris. The iris is part of the uvea, which is the middle of the three tissue layers forming the eyeball’s wall. That allows the herpes infection to spread into the uvea and become a greater threat. It can cause pain, blurry vision, redness, and severely increased light sensitivity.
- Herpes retinitis is infection of the retina at the back of the eye.
Diagnosis and Treatment
Ocular herpes can be detected by a slit lamp test. Treatment normally involves the use of anti-viral eye drops and/or oral medications. Steroid drops may also be used to decrease inflammation and prevent scarring. Sometimes debridement is required, which is scraping off the infected corneal epithelial cells. In severe cases a corneal transplant is necessary.
Ocular Herpes and LASIK
If you have ocular herpes and are considering LASIK surgery, you must discuss your condition with your ophthalmologist. Ocular herpes does not always disqualify you for LASIK, but it does increase the risk of complications and possible blindness.
LASIK surgery may be interpreted by your body as trauma – one of the things that can cause ocular herpes to flare up. Certain immune responses to ocular herpes can increase the damage it causes to the cornea. Immuno-compromised patients are at the greatest risk. They are more likely to experience a flare up and if they do, it is more likely to be severe.
The benefits vs. risks should be evaluated on a case by case basis. If you and your ophthalmologist decide that LASIK surgery is still appropriate, precautions can be taken to minimize the risks.
If you are considering LASIK surgery and have ocular herpes, you can talk to an experienced ophthalmologist today.