Eye numbness or corneal anesthesia, also known as neurotrophic keratopathy, is a condition where the nerves in the cornea are absent or damaged, which can eventually lead to blindness. Corneal neurotization is a surgery offered by Leon Rafailov, MD a board certified, fellowship-trained ophthalmic plastic surgeon at SightMD that can replace these nerves and protect the eye from future damage and permanent blindness.

What is Neurotrophic Keratitis

Neurotrophic keratitis is a rare eye disorder that affects the cornea. The cornea (the transparent, most outer portion of the eye) must be completely clear in normal vision. Neurotrophic Keratopathy (NK) occurs when people cannot feel their corneas. With this loss of feeling, people can’t protect the cornea, making the cornea vulnerable to injury. Typically, a scratch on the cornea is extremely painful; however, people without corneal nerves don’t notice debris in the eye, such as dirt, sand, and other irritants. Over time, these scratches cause scarring and clouding of the cornea. Once the cornea becomes cloudy, a decline in vision becomes permanent because the scarring blocks light from getting to the inside of the eye.

What are the symptoms of Neurotrophic Keratitis

Since corneal sensory innervation is impaired in Neurotrophic Keratitis, patients do not commonly complain of ocular surface symptoms. This makes Neurotrophic Keratitis particularly challenging, as patients may seek medical advice months or years after the disease has started. Early on, affected individuals may not have any symptoms of the disorder since the sensitivity of the cornea is reduced. Affected individuals often do not complain of pain or discomfort in the eye. Blurred vision, red eyes, dry eyes, and decreased clarity of vision can develop. Affected individuals may become extremely sensitive to light. The affected cornea can be injured easily and it heals itself slower than an unaffected cornea does. This leaves the cornea susceptible to damage. Affected individuals may experience frequent or recurrent corneal erosions, which is when an opening in the epithelial layer develops. Since the epithelial layer is the protective layer of the cornea, an epithelial defect can leave the eye more susceptible to infection.

What causes Neurotrophic Keratitis

Neurotrophic keratitis can be caused by any condition or disorder that affects the nerves that serve the cornea. The main nerve that serves the cornea is called the trigeminal nerve, which is also called the fifth cranial nerve. Damage to the ophthalmic division of the trigeminal nerve, which serves the cornea, can cause neurotrophic keratitis. When the nerves that serve the cornea are damaged this causes reduced sensitivity of the cornea and can lead to neurotrophic keratitis.

How is Neurotrophic keratitis Diagnosed

The diagnosis of neurotrophic keratopathy is generally made without difficulty based on history and examination findings. It is imperative to remember that the common finding in all cases is a decrease in corneal sensation. In stage 1 disease, punctate epithelial staining with fluorescein is a nonspecific sign and may be found in other conditions, including dry eye syndrome, blepharitis, chronic eye rubbing, exposure keratopathy, topical drug toxicity, ultraviolet keratopathy, mild chemical injury, contact lens– related disorders and corneal limbal stem cell deficiency. A careful medical and surgical history is important to sort through this differential diagnosis.

An ulcerated appearance of the cornea must raise suspicion for other causes, including infectious and immune etiologies. Appropriate cultures must be obtained and an immune work-up should be considered.

Are There Any Treatments for Neurotrophic Keratopathy?

Your doctor may recommend corneal neurotization surgery, the first procedure to halt corneal anesthesia. Corneal neurotization is a minimally invasive surgery where nerves are redirected from other parts of the body into the cornea to stop the progression of corneal numbness. This treatment helps prevent blindness and further damage to your eye sight.

What to Expect with Corneal Neurotization Surgery

You will first visit an ophthalmic plastic surgeon to develop a treatment plan. Our team will then meet with you to discuss how corneal neurotization works, what to expect and answer any questions you or your child may have. Corneal neurotization surgery begins by locating a healthy nerve. Next, a nerve segment is used as an “extension cord” to allow nerve cells to grow into the eye. This nerve is then tunneled under the skin, under the lining of the outer eye and into the cornea. Finally, your surgeon will sew the eyelid(s) shut to protect the new nerves. These stitches will be removed at your follow-up appointment the following week. Once in place, the new nerve will begin to provide sensation to the eye and stop any further scarring or ulcerations that damage the cornea and limit vision. If you already have corneal scarring, the new nerve helps them become eligible for a cornea transplant.

What to Expect after Corneal Neurotization Surgery

For a week following surgery, your affected eyelids are temporarily closed to protect the newly grafted nerve. You will also have a bandage on the area where the nerve was removed. For six weeks after corneal neurotization, you must rest and avoid any physical activity, including sports, to allow the eye to heal completely. Over the next two to four months, you will regain feeling in the cornea, but complete regrowth of the nerve can take up to a year.

What are the Benefits of Corneal Neurotization surgery?

In a majority of cases, this surgery has fully reinstated feeling and nerve function in the affected eye. This surgery has the power to restore protective corneal sensation, prevent further scarring of the cornea and ultimately, reinstate a patient’s vision. Corneal neurotization surgery offers a promising option to patients affected by corneal anesthesia.

Meet Our Corneal Neurotization Surgery Expert

Leon Rafailov, MD is a board certified, fellowship-trained ophthalmic plastic surgeon who focuses on a wide range of plastic and reconstructive surgery in the area around the eyes. His areas of expertise include the eyelids, forehead, mid-face, orbit, and tear ducts. He has successfully completed thousands of reconstructive, cosmetic, functional, and orbital surgeries. He has published numerous journal articles, abstracts, and book chapters focusing on a wide range of topics in oculoplastics. Dr. Rafailov is trained in advanced techniques in minimally invasive endoscopic surgery, facial reconstruction, trauma surgery, orbital surgery, oncologic surgery, and cosmetic surgery. While in fellowship at Duke, he contributed to research in corneal neurotization and received the “Fellow of the Year” award for teaching. He prides himself in providing specialized and patient-focused care using a custom approach to every patient. He is well known by his patients for his personalized and attentive care.