Scleral Lenses for Neurotrophic Keratitis
What Is Neurotrophic Keratitis?
Neurotrophic keratitis occurs when the nerves supplying sensation to the cornea are damaged, leading to a decreased blink reflex, reduced tear production, and impaired healing. This results in an increased risk of corneal injury and persistent ulcers that are slow to heal.
Damage to the corneal nerves can arise from multiple causes, such as:
- Eye surgeries including LASIK, cataract surgery, or corneal transplant
- Infections such as herpes simplex virus or herpes zoster ophthalmicus (shingles)
- Systemic diseases like diabetes mellitus that impair nerve function
- Chronic or improper contact lens wear causing corneal irritation
- Neurological disorders including multiple sclerosis, stroke, or trigeminal nerve damage
Typical symptoms include dryness, redness, recurrent epithelial defects or ulcers, and blurred vision. An unusual lack of pain due to the loss of corneal sensation is a key sign that often delays diagnosis and treatment.
Several groups have a higher chance of developing neurotrophic keratitis, such as:
- Patients with poorly controlled diabetes or other systemic neuropathies
- Individuals with a history of ocular surgeries or trauma
- People affected by herpes zoster affecting the eye or face
- Patients with neurological diseases impacting the trigeminal nerve
- Those with autoimmune conditions that affect nerve or ocular surface health
Neurotrophic keratitis is classified into three stages based on the severity of corneal damage:
- Stage 1: Superficial punctate keratopathy with mild epithelial changes and dryness.
- Stage 2: Persistent epithelial defect without stromal involvement.
- Stage 3: Corneal ulceration, stromal melting, and risk of perforation.
How Scleral Lenses Help
Scleral lenses are specialized gas-permeable contact lenses that create a stable, hydrated environment over the eye’s surface to protect the cornea and promote healing.
Each lens is individually designed based on detailed measurements of the eye. The lens vaults over the cornea and rests on the sclera, preventing direct contact with damaged tissue while providing a stable and comfortable fit.
A reservoir of sterile, preservative-free saline between the cornea and the back of the lens maintains continuous hydration. This is essential for healing damaged epithelial cells and reducing inflammation.
Scleral lenses shield the cornea from environmental irritants such as wind, dust, and allergens. This protection prevents further damage and minimizes discomfort from blinking.
By masking surface irregularities and providing a uniform refractive surface, these lenses improve visual clarity that is often compromised by corneal scarring or ulceration.
Modern scleral lenses are made from highly oxygen-permeable materials. This allows the cornea to breathe, which is crucial for maintaining long-term corneal health and safety.
Scleral lenses are most effective when combined with other treatments to support healing, including:
- Preservative-free artificial tears to boost lubrication
- Autologous serum eye drops rich in growth factors
- Topical nerve growth factor therapy to stimulate nerve regeneration
- Amniotic membrane grafts for severe cases
Fitting Process
A precise and careful fitting process is critical to maximize the benefits of scleral lenses while minimizing potential risks to ensure comfort and effectiveness.
A comprehensive evaluation includes corneal topography, ocular surface health assessment, and tear film analysis to customize lens parameters for your specific eye shape and needs.
Trial lenses of varying diameters and vault heights are placed on the eye to evaluate fit, stability, and comfort, helping to determine the optimal lens design.
OCT imaging is often used to measure the lens clearance over the cornea with micron-level precision. This ensures an adequate fluid reservoir without excessive vault or corneal compression.
Lenses are filled with sterile, preservative-free saline solution before insertion to create the fluid reservoir that sits directly against the cornea.
Patients receive detailed guidance and hands-on training on the proper techniques for lens insertion, removal, and daily care to maintain effectiveness and avoid complications.
Regular follow-up appointments are essential to monitor the lens fit, corneal condition, and overall ocular response, with adjustments made as necessary.
Caring for Your Lenses
Adhering to strict hygiene and care routines is essential to maintain the condition of your lenses and the health of your eyes.
Rinse lenses with an approved solution and gently rub them to remove protein deposits and debris before soaking them overnight.
Use an approved disinfection system, such as a hydrogen peroxide-based or multipurpose solution, to eradicate microorganisms and maintain lens sterility.
Always wash your hands thoroughly before handling your lenses. Using a lint-free cloth or a specialized applicator can help avoid damage or contamination.
Store your lenses in a clean case filled with fresh disinfecting solution. You should replace your lens case at least every three months to minimize infection risks.
Most scleral lenses are designed to be replaced every one to two years. Your eye doctor will inspect them at follow-up visits and advise you when a replacement is needed.
Potential Risks and Side Effects
While scleral lenses are very safe, it is important to be aware of possible complications to ensure prompt management and long-term success.
Mild awareness or irritation may occur initially but typically resolves as the eye adapts over a period of a few days to two weeks.
Failure to maintain strict hygiene is the primary cause of infections such as microbial keratitis. Following all care instructions is essential to prevent this serious complication.
Rubbing your eyes or an improper fit can cause the lens to shift, leading to blurred vision and discomfort. This can be resolved by repositioning the lens or being refitted by your doctor.
Wearing lenses longer than recommended or using a lens with compromised oxygen transmission can cause corneal swelling, which may harm your vision.
Rarely, prolonged lens wear can cause inflammatory responses like conjunctivitis or sterile infiltrates, which require medical evaluation.
Frequently Asked Questions
Below are answers to common questions patients have about using scleral lenses for neurotrophic keratitis.
Most patients adapt within a few days to two weeks. Initial awareness of the lens on the eye will decrease as you become accustomed to wearing it.
Scleral lenses create an ideal healing environment by hydrating and protecting the cornea, but they work best as part of a comprehensive treatment plan that may include other medical therapies.
Typical daily wear time is between 8 to 12 hours. However, your specific wearing schedule will be determined by your eye doctor based on your individual eye health.
They benefit many patients, especially those with mild to moderate disease. However, a professional evaluation is essential to determine if they are the best option for your specific case.
Only sterile, preservative-free saline solutions are safe for filling the lens bowl. Saline solutions containing preservatives or multipurpose disinfecting solutions should never be used to fill the lens.
Replacement typically occurs every one to two years, depending on the lens material, your tear chemistry, and how well you care for them. Regular eye exams will guide the appropriate timing.
Most daily activities are safe. However, swimming, showering, or using a hot tub while wearing lenses is strongly discouraged to prevent serious eye infections from waterborne microorganisms.
Yes, by creating a perfectly smooth optical surface over an irregular or scarred cornea, scleral lenses often provide a significant improvement in vision.
You should seek immediate care from your eye doctor if you experience persistent redness, pain, sudden changes in vision, discharge, or discomfort that does not improve after removing the lens.
Yes, most patients experience good comfort. Because scleral lenses rest on the less-sensitive sclera and vault over the cornea, they avoid direct contact and provide a cushioning effect.
Overnight wear is generally not recommended due to an increased risk of infection and reduced oxygen delivery to the cornea while you sleep.
Scleral lenses physically protect and hydrate the cornea, complementing medical treatments like topical medications, amniotic membranes, or nerve growth factor therapy.
Next Steps
If you have neurotrophic keratitis, consult our eye doctors to see if scleral lenses can be part of a tailored treatment plan to promote healing, protect your vision, and improve your quality of life.