Scleral Lens for Keratoconus

What is Keratoconus?

Keratoconus is a progressive eye disorder in which the normally round cornea thins and begins to bulge outward into a cone-like shape. This cone shape deflects light as it enters the eye, causing distorted vision. Keratoconus typically begins during puberty and progresses until the mid-30s, though the rate of progression varies significantly between individuals.

The exact cause of keratoconus remains unclear, but genetic predisposition, environmental factors, excessive eye rubbing, and certain systemic conditions may contribute to its development. The condition can occur in one or both eyes and can progress at different rates in each eye.

Symptoms of Keratoconus

Keratoconus typically manifests with several distinctive symptoms that often worsen as the condition progresses:

• Blurred or distorted vision that cannot be corrected with regular glasses

• Increased sensitivity to light and glare, especially when driving at night

• Frequent changes in eyeglass prescriptions

• Cloudy or halos around bright lights

• Eye strain, headaches, and general eye discomfort

• Progressive nearsightedness and irregular astigmatism

• Double vision or multiple images when viewing with just one eye

• Difficulty with night vision

As keratoconus advances, even simple daily activities like reading or driving can become challenging. Many patients report having to squint or close one eye to see more clearly, which can lead to additional eye strain and fatigue.

What are Scleral Lenses?

Scleral lenses are specialized rigid gas permeable contact lenses with a significantly larger diameter than conventional contact lenses. Unlike traditional contacts that rest directly on the cornea, scleral lenses vault over the entire corneal surface and rest on the white part of the eye (the sclera).

These advanced lenses range from 14mm to 24mm in diameter and create a fluid-filled space between the lens and the cornea. This design makes them fundamentally different from conventional contacts in both form and function.

Scleral lenses are custom-made for each patient using precise measurements and advanced technology to ensure an optimal fit. The rigid material maintains its shape while on the eye, providing a smooth optical surface regardless of corneal irregularity.

Why are Scleral Lenses Ideal for Keratoconus?

Scleral lenses have emerged as a preferred treatment option for keratoconus patients for several compelling reasons:

• They vault over the irregular cornea, avoiding direct contact with the sensitive, cone-shaped area

• The fluid reservoir between the lens and cornea fills in corneal irregularities, creating a smooth optical surface

• They provide superior visual acuity compared to soft contacts or glasses for most keratoconus patients

• Enhanced comfort due to minimal movement and reduced friction on the cornea

• Stable vision throughout the day without fluctuations common with other correction methods

• Protection for the corneal surface from environmental irritants and the mechanical trauma of blinking

• Reduced risk of scarring by minimizing direct contact with the fragile corneal tissue

• All-day wearing time for most patients, supporting normal daily activities
  

For many with moderate to severe keratoconus, scleral lenses represent a non-surgical alternative that can delay or potentially eliminate the need for corneal transplant surgery.

How do Scleral Lenses Work for Keratoconus?

Scleral lenses effectively manage keratoconus through their unique design and fitting principles:

1. Corneal Vaulting: The lens creates a dome over the irregular cornea, completely clearing the cone-shaped protrusion without touching it.

2. Liquid Reservoir: The space between the lens and cornea fills with preservative-free saline solution, creating a smooth, liquid interface that neutralizes corneal irregularities.

3. Rigid Optics: The gas-permeable material provides excellent optical clarity and maintains its shape, creating a regular optical surface regardless of corneal distortion.

4. Stable Platform: By resting on the less sensitive sclera rather than the cornea, the lens remains centered and stable throughout wear.

5. Oxygen Permeability: Modern scleral lenses are made from highly oxygen-permeable materials, allowing adequate oxygen to reach the cornea despite the fluid layer.
   

This combination of features results in dramatically improved visual acuity and comfort for most keratoconus patients who have struggled with conventional correction methods.

Who Will Benefit from Scleral Lenses?

Scleral lenses can be life-changing for various patients, particularly those with:

• Moderate to advanced keratoconus where conventional contacts or glasses provide insufficient vision correction

• Post-surgical corneal irregularities following procedures like corneal transplants or LASIK complications

• Severe dry eye syndrome that makes traditional contact lens wear uncomfortable

• Ocular surface disease requiring protection of the corneal surface

• High astigmatism that isn't adequately corrected with standard lenses

• Corneal scarring from injury or disease

• Patients intolerant to other contact lens options due to discomfort or instability

• Active lifestyles requiring stable vision during physical activities

Patients who have been told they're "hard to fit" for contact lenses often find that scleral lenses provide both the comfort and visual clarity they've been seeking.

What to Expect During a Scleral Lens Fitting

The scleral lens fitting process is more specialized than standard contact lens fittings and typically involves:

1. Comprehensive Evaluation: A detailed examination including corneal topography mapping to measure the exact shape of your cornea.

2. Diagnostic Lens Assessment: Trial lenses are placed on the eye to evaluate the fit, with special attention to the vault over the cornea and landing on the sclera.

3. Vision Assessment: Once an appropriate fit is achieved, visual acuity is measured and refined.

4. Insertion and Removal Training: You'll receive thorough instruction on proper handling, insertion, removal, and care of your scleral lenses.

5. Solution and Care System: Your eye care professional will recommend specific solutions and cleaning procedures for your lenses.

6. Follow-up Schedule: Initial follow-up visits are typically scheduled within the first week of wear, with periodic check-ups to monitor corneal health and lens fit.

7. Adaptation Period: Most patients require 1-2 weeks to fully adapt to scleral lenses, though vision improvement is often immediate.

The fitting process may require multiple visits to achieve the optimal prescription and fit. While this represents a greater initial investment of time compared to standard contacts, the results are well worth the effort for most keratoconus patients.

Scleral lenses are a specialized treatment requiring expertise to fit properly. Seeking an eye care professional with specific training and experience in fitting scleral lenses for keratoconus will provide the best outcomes.

Why Choose Nexus Vision Eye Care for Scleral Lenses?

At Nexus Vision Eye Care we specialize in providing cutting-edge solutions for keratoconus. With a team of experienced optometrists and state-of-the-art equipment, we ensure a seamless experience from diagnosis to treatment.


Reference: BostonSight | PROSE Treatment for Cornea Disease and Dry Eyes