Scleral Contact Lenses

Scleral Lenses: The Advanced Solution for Irregular Corneas and Dry Eye

Scleral lenses are a type of large-diameter (15-22 mm) rigid gas permeable (RGP) contact lens that rests on the sclera (white of the eye) and creates a saline-filled space above the cornea. They are ideal for patients with irregular corneas, severe dry eye, or intolerance to other contact lenses.

What makes them unique?

✅ Large and stable design: They do not move when blinking.

✅ Corneal protection: They create a moist chamber that lubricates and protects the ocular surface.

✅ Optimal oxygenation: Made of high-oxygen permeability materials.

✅ Customization: They are custom-designed using corneal topography technology and a proper fit with trial lenses.

Main Indications

✔ Advanced keratoconus (when standard RGPs are not tolerated).

✔ Severe dry eye syndrome (e.g., Sjögren's syndrome, ocular pemphigus).

✔ Post-corneal surgery (transplant, crosslinking, intracorneal rings).

✔ High irregular astigmatism (due to trauma or failed refractive surgery).

✔ Corneal exposure (in patients with facial paralysis or lagophthalmos).

Types of Scleral Lenses

Mini scleral lenses: 15-16 mm (In Mexico, the brands authorized by Cofepris belong to this type).

For moderate dry eye, slightly irregular corneas.

However, standard scleral lenses: 17-18 mm and large scleral lenses: 19-22 mm are also available.

Scleral Advantages

Stability ⭐⭐⭐⭐⭐ (Very little movement)

Comfort ⭐⭐⭐⭐⭐ (More than other designs)

Visual Quality ⭐⭐⭐⭐ (Optimal, dependent on eye health)

Maintenance ⭐⭐⭐⭐ (Daily cleaning, potentially fragile)

⚠️ Disadvantages and Considerations

❌ Longer adaptation (7-14 days per lens seating).

❌ More complex handling (due to size, it takes several days for some people).

❌ Higher cost (due to custom design).

❌ Risk of hypoxia if not removed for prolonged periods (>12 hours) or if the fit is poor.

Care and Maintenance

Clean hands and surface.

Fill with sterile saline solution before inserting.

Daily cleaning with special solutions for rigid lenses.

Store in a case with disinfectant liquid.

Replace every 1-2 years (depending on the material).

Who Should Use Them?

This is under professional supervision, as there are many other options before scleral lenses.

Patients with keratoconus who cannot tolerate conventional RGP lenses.

People with severe dry eye (they replace natural tears).

Post-complex corneal surgeries (e.g., corneal transplant).

Athletes who require extreme visual stability (e.g., cyclists, swimmers).

Contraindications:

Allergies to materials.

Active eye infections (conjunctivitis, keratitis).

Misuse or overuse.

Inability to handle them (they require dexterity).

They improve vision in 95% of patients with keratoconus (Journal of Cornea and External Disease).

They reduce dry eye symptoms by 80% (American Academy of Ophthalmology).

In Mexico, their use has increased by 40% in the last decade (American Optometric Association).

Why Are Scleral Lenses So Expensive?

Scleral lenses represent the most advanced technology in contact lenses, and their high price (between $8,000 and $20,000 MXN per pair) is due to:

Custom Design

Unlike standard soft lenses, scleral lenses are custom-made for each eye, using data from:

Corneal topography (3D map of the cornea).

Many variables are considered for proper fitting, which involves materials and consultation time.

This guarantees a perfect fit, especially in irregular corneas (keratoconus, post-transplant).

High-Tech Materials

They are made from cutting-edge polymers.

Some include non-stick surface treatments for greater durability.

Manufactured in Specialized Laboratories

In Mexico, they can be ordered from retailers such as:

Lumilent Laboratories

Mediphacos / Arfamex (focused on designs for keratoconus).

Maxim (USA, but with distributors in Mexico).

The process involves multiple fittings and international shipping in some cases.

Expert Fitting

Requires certified scleral lens optometrists, who perform:

Slit-lamp evaluation to observe clearance (space between the cornea and the lens).

Diameter and curvature adjustments based on ocular response.

Is it worth the investment?

✅ Clear, comfortable vision where other lenses fail.

✅ Corneal protection for severe dry eye.

✅ Longevity (1-2 years with proper care).

Can I avoid using scleral lenses?

If you want to avoid using scleral lenses but need to correct vision problems associated with irregular corneas (such as keratoconus) or severe dry eye, there are several alternatives. Here are their classifications, classified by type of need:

1. Alternatives for Irregular Corneas (e.g., keratoconus)

A. Conventional Rigid Gas Permeable (RGP) Contact Lenses

Advantages:

More economical than scleral lenses ($3,000-$8,000 MXN).

Good balance between oxygenation and visual quality.

Disadvantages:

Less comfortable (they rest on the cornea).

They can shift in very irregular corneas.

B. Hybrid Lenses

Combining a rigid center (for clear vision) + soft edge (for comfort).

Brands in Mexico: SynergEyes, UltraHealth.

Price: $6,000-$15,000 MXN.

C. Special Soft Lenses for Keratoconus

Custom toric designs.

Advantage: More comfortable than RGPs.

Limitation: Not manufactured in Mexico.

D. Intracorneal Rings (ICRS: Intacs, Keraring)

What they are: Segments that flatten the cornea (implanted surgically).

Advantage: Reduce dependence on contact lenses.

Cost: $20,000-$40,000 MXN per eye.

E. Corneal Crosslinking (CXL)

Slows the progression of keratoconus (does not correct vision on its own).

Can be combined with glasses or soft contact lenses.

2. Alternatives for Severe Dry Eye

A. Silicone Hydrogel Soft Contact Lenses

Materials: e.g., Alcon Dailies Total1, Johnson & Johnson Oasys.

Advantage: They retain moisture and allow good oxygen flow.

B. Punctal Tamponade

Silicone plugs that retain tears in the tear ducts.

A quick procedure (performed by the ophthalmologist).

C. Autologous Serum

Artificial tears made from the patient's blood (for severe cases).

3. Non-Contact Lens Options

A. Spectacles with Special Lenses

For keratoconus: Lenses with high-definition filters or prisms.

Limitation: They do not provide 100% correction in advanced cases.

B. Refractive Surgery with Intraocular Lens (ICL)

For high myopia + stable keratoconus.

It does not touch the cornea (the lens is placed between the iris and the lens).

C. Corneal Transplant (Last Resort)

Indicated if there is scarring or very low vision.

Alternatives: DALK (partial) or PKP (complete).

How to Choose the Best Option?

Mild keratoconus

RGP or hybrids.

Advanced keratoconus

Intracorneal rings + Crosslinking

Dry eye + stable vision

Soft silicone hydrogel lenses.

Avoid surgery

Custom eyewear.