What herpes does to the cornea
Herpes simplex keratitis is an infection of the cornea by the herpes simplex virus, usually HSV-1, the same virus that causes cold sores. It’s the leading infectious cause of corneal ulcers and blindness worldwide. After a first infection the virus lies dormant in a nerve and can travel back to the cornea later, which is why it tends to recur.[1]
Repeated or deep infections can cause:
- Scarring. Inflammation in the corneal tissue can leave scars that make the cornea hazy, uneven, or both.[1]
- Reduced corneal feeling. Herpes damages corneal nerves. Reduced sensation can last after the infection itself has resolved. Across studies, between 6% and 27% of people go on to develop neurotrophic keratopathy after herpes simplex infection, a condition in which the cornea heals poorly because its nerves don’t work properly.[4]
How scleral lenses can help
Scars from herpetic stromal keratitis, the deeper form of the infection, are among the causes of an irregular, scarred cornea that scleral lenses are used for.[2] The fluid under the lens fills in the uneven surface, and the lens’s smooth front surface takes over as the focusing surface. It doesn’t clear haze: if a scar is dense and central, vision through it will still be limited.[2]
If herpes has left you with neurotrophic keratopathy, scleral lenses are sometimes used to protect the cornea and help it heal, under close supervision.[4] See scleral lenses for neurotrophic keratitis and corneal scarring.
Recurrence: what’s known
Evidence on contact lenses and herpes recurrence is thin:
- A study at one clinic reviewed 117 people with herpes simplex keratitis, 21 of whom wore contact lenses. The lens wearers had more recurrences per year (a median of 0.4 episodes a year, compared with 0.2), and lens wear stayed a significant factor after accounting for other differences. The authors advised counseling people with a history of herpes keratitis about a possible increased risk.[3]
- That was a small, retrospective study, and its summary doesn’t say which lens types people wore. It wasn’t about scleral lenses specifically.
- In a larger study of 1,303 people with corneal infections, viruses were the second most common cause among those with recurrent infections.[5]
None of this proves scleral lenses trigger flare-ups. It does mean the question is worth raising with your eye doctor before you start, especially if you’ve had several recurrences.
Questions to ask before you start
- Is the eye quiet enough to start, and how long should I wait after a flare?
- How should we handle antiviral treatment while I’m wearing lenses?
- What should I do if I think a flare is starting?
- How often do you want to see me?
- If my corneal feeling is reduced, which other symptoms should I watch for?
Common questions
Should I take antiviral medicine while wearing scleral lenses?
That's a question for your eye doctor. Antiviral treatment decisions depend on your history of recurrences and the type of herpes eye disease you've had. Tell your doctor you're considering scleral lenses so it's part of the discussion, and don't start, stop or change antiviral medicine on your own.
How would I know if the herpes is coming back while I wear lenses?
Signs of a flare and signs of a lens problem can look alike. The FDA's warning signs for lens wearers include discomfort, unusual redness, unusual sensitivity to light, excess tearing, and blurred vision. Because herpes can reduce corneal feeling, symptoms may be milder than you'd expect. Treat any of these as a reason to remove the lens and call your eye doctor the same day.
Does wearing a lens cause herpes to come back?
Repeat episodes of herpes keratitis come from virus that is already dormant in the body reactivating. Whether contact lens wear makes that more likely isn't settled: one small study found more frequent recurrences in lens wearers, but it couldn't prove the lenses were the cause. Follow your eye doctor's advice about lens wear during and after any flare.