Scleral Lenses for Keratoconus: How They Restore Clear Vision

Keratoconus causes the cornea to gradually thin and bulge into an irregular, cone-like shape. As the surface becomes less regular, glasses and standard soft lenses become progressively less able to correct vision — not because the eye is unhealthy in a general sense, but because light can no longer be focused predictably through a distorted surface. Scleral lenses are one of the most effective non-surgical ways to restore clear, stable vision for many patients with keratoconus.

Why keratoconus makes vision hard to correct

A healthy cornea is smooth and regularly curved, so glasses can bend light to a single, sharp focus point. In keratoconus, the surface becomes irregular in a way that varies from person to person and often changes over time. Glasses can’t correct this irregular distortion, and standard soft lenses simply drape over the irregular surface rather than correcting it.

How scleral lenses help

A scleral lens vaults entirely over the cornea, resting instead on the sclera — the white of the eye — without ever touching the irregular corneal surface. The space between the back of the lens and the front of the eye fills with fluid, creating a new, smooth, optical surface for light to pass through. In effect, the lens takes over the job the irregular cornea can no longer do.

Since 2010, Craig McArthur has fitted scleral lenses for keratoconus patients at Peter Ivins Eye Care, using corneal topography to map the precise shape of each irregular cornea and Zeiss Cirrus 6000 anterior OCT imaging to check exactly how the lens sits on the eye once fitted.

What to expect from the fitting process

• An initial assessment including corneal topography, to map the shape and severity of the keratoconus
• One or more diagnostic lenses, worn briefly to assess fit and comfort
• Anterior OCT imaging to check clearance over the cone and alignment at the lens edge
• A final lens, manufactured to the confirmed design
• Follow-up appointments to fine-tune the fit as needed

Can scleral lenses restore 20/20 vision in keratoconus?

For many patients, scleral lenses restore vision close to 20/20 by giving the eye a smooth, regular optical surface again. The result that’s realistically achievable depends on how advanced the keratoconus is and the overall health of the eye, which is why assessment is done individually rather than promised in advance.

Scleral lenses after corneal cross-linking

A common referral scenario is a patient who has had corneal cross-linking (CXL) to halt progression of their keratoconus, and now needs a scleral lens fitting to correct the vision left by the irregular shape CXL has stabilised. CXL treats progression; it doesn’t reverse the corneal irregularity already present, so many patients still need a scleral lens afterwards for clear vision. We cover the timing and specifics of fitting after CXL in a dedicated article.

Keratoconus & Scleral Lens FAQs

Can scleral lenses stop keratoconus getting worse?

Scleral lenses correct vision by masking the irregular corneal surface — they don’t treat the underlying progression of keratoconus itself. If your keratoconus is still progressing, your optometrist or ophthalmologist may also discuss corneal cross-linking (CXL) alongside scleral lens fitting.

Are scleral lenses comfortable for keratoconus patients?

Most keratoconus patients find scleral lenses considerably more comfortable than corneal RGP lenses, because the lens rests on the less-sensitive sclera rather than directly on the irregular, often more sensitive cone.

How long does it take to get used to scleral lenses for keratoconus?

Most patients adapt within one to two weeks of starting full-time wear, though this varies. We schedule follow-up appointments during this period to check the fit is settling correctly.

Do I need scleral lenses in both eyes if only one eye has keratoconus?

Not necessarily — keratoconus often affects both eyes but at different rates, so treatment is planned per eye based on its individual shape and vision.

Book a Scleral Lens Assessment

Call the practice on 0141 943 3300 to arrange a scleral lens consultation.