What is neurotrophic keratitis?
Neurotrophic keratitis is a degenerative condition that results in decreased density of corneal nerves. The cornea is the front layer of your eye, like a clear windshield protecting the parts that lie underneath. The cornea doesn’t contain blood vessels. Because of this, in addition to sensation the cornea gets important growth and healing support from its nerves.
The degeneration of the corneal nerves results in a loss of corneal sensitivity and reduces your ability to feel eye pain or irritation, making the corneas less able to protect the eyes from hazards. Everyday hazards to the eyes, such as dust, debris or wind, can cause corneal scratches, infections or ulcers that can greatly reduce vision if left untreated.
The loss of sensitivity also leads to less blinking and tear production, creating very dry eyes.
Frequently, neurotrophic keratitis will only affect one eye.
What causes neurotrophic keratitis?
There are several possible causes. The most common include:
- Eye infection
- Burns to the eye
- Diabetes
- Cranial nerve injury
- Chronic ocular surface disease
- Congenital causes
Additionally, viruses, such as cold sore virus or chicken pox, can damage the cornea and nerves, leading to harm. Developing any tumors that affect nerves or having an aneurysm or a stroke can also cause neurotrophic keratitis.
Symptoms and diagnosis
If you have neurotrophic keratitis, you may experience symptoms that include red eyes and blurry vision. It’s also possible to not experience any symptoms, since the condition affects nerves that would cause pain; if your pain response is blunted, you wouldn’t know something may be wrong.
The condition is often first noticed and diagnosed during an eye exam by your ophthalmologist, an eye doctor who will identify this condition by looking at the outer layer of the cornea during a slit lamp examination. The ophthalmologist can see the cornea breaking down and not healing, which may lead to an epithelial defect or even a hole in the cornea. Your ophthalmologist would then test your corneal sensitivity with a gentle poke from a cotton swab or a corneal esthesiometer, a special nylon filament, to find out whether you feel it or not.
How is neurotrophic keratitis treated?
To treat the condition, our experts begin by exploring nonsurgical options including:
- Medicated eye drops
- Amniotic membranes that slowly dissolve on the eye
- Nerve growth factor eye drops
- Tear drain plugs, designed to help keep moisture on the cornea
- Specialized contact lenses, such as soft bandage contacts and scleral lenses
In rare cases, corneal neurotization surgery may be recommended.
Corneal neurotization surgery for neurotrophic keratitis
Corneal neurotization surgery is a minimally invasive, small-incision nerve transplant procedure. The goal is to restore innervation and get nerves to grow in the cornea again by rerouting other nearby nerves.
Because usually only one eye is affected by this condition, your surgeon can use a nerve graft from the opposite side of the face, cross the nerve under the eyelid and conjunctiva (mucosal membrane), divide it into branches and attach it to the affected cornea. The newly grafted nerves should grow about 1 millimeter per day, restoring sensation after about six months.
The procedure takes two to three hours and includes an incision in the crease of both eyelids. Stitches (sutures) in the eyelid and cornea can be removable or dissolvable. You won’t be able to see the stiches on the cornea.
This surgery is done under general anesthesia, and you can go home the same day, but will need someone to drive you to and from surgery.
Postsurgery care and recovery
Often, your cornea will be irritated, and the eyelid will be sutured closed for one to three weeks. An eye patch may also be worn following surgery. Your doctor will let you know when you can wear contact lenses again. Depending on your eyes, you may not be able to wear contact lenses for up to six months.
There will be several follow-up appointments after surgery. For the first month, you may see your ophthalmologist once every few weeks, then less frequently after that.
Following surgery, your surgeon will typically prescribe eye drops. You may experience bruising, redness and irritation for one to two months following surgery.
Surgery results
The nerves typically need six months to grow, and you may not notice results until then. This surgery may not return your eye to complete normalcy, but it can help you regain some vision and make the surface of your eye healthier and prevent further damage.
If you were unable to have a corneal transplant previously, corneal neurotization surgery can increase your eligibility for a cornea transplant surgery in the future.
Is the surgery covered by insurance?
Corneal neurotization surgery is typically covered by health insurance. Make sure to consult your provider for details on coverage.
Why choose Ohio State Ophthalmology for corneal neurotization surgery?
Ohio State Ophthalmology is one of only a few medical centers in Ohio to offer this procedure. It requires the expertise of both an oculoplastic surgeon and a corneal surgeon. This is a collaborative, rare and state-of-the-art surgery performed by specialist eye surgeons.