Collagen Cross-Linking (C3R / CXL)

Stopping Keratoconus in Its Tracks

Keratoconus is a condition in which the cornea — the clear dome at the front of the eye — gradually thins and bulges forward into a cone shape, causing progressive and increasingly distorted vision. For years, there was no treatment that could halt this progression. Collagen Cross-Linking changes that entirely. This minimally invasive procedure strengthens the corneal tissue at a molecular level, stopping keratoconus from progressing and protecting the vision you have. At RGC Eye Hospital, we offer this treatment to eligible patients with the care and precision it requires.

What Is Collagen Cross-Linking?

Collagen Cross-Linking — known as CXL or C3R — is a procedure that uses riboflavin (vitamin B2) eye drops combined with controlled ultraviolet-A light to create new bonds between the collagen fibres within the cornea. These new cross-links stiffen and strengthen the corneal tissue, significantly increasing its resistance to the progressive thinning and bulging that characterises keratoconus. While CXL does not reverse existing distortion, it is highly effective at halting further progression — which is its primary and most important goal.

Who Is CXL For?

• Patients with confirmed keratoconus that is demonstrably progressing
• Young patients in whom progression is most likely and most damaging over time
• Patients with other ectatic corneal conditions such as pellucid marginal degeneration
• Those who have had LASIK and developed post-operative corneal ectasia
• Patients whose cornea is thick enough to safely undergo the procedure

What Happens During the Procedure?

Step 1 — Preparation

Anaesthetic drops are applied. The surface cells of the cornea (epithelium) are gently removed in the standard CXL technique to allow the riboflavin to penetrate deeply into the corneal stroma.

Step 2 — Riboflavin Application

Riboflavin drops are applied to the cornea repeatedly over a period of around 30 minutes to allow thorough saturation of the corneal tissue.

Step 3 — UV Light Treatment

The cornea is exposed to a carefully calibrated dose of ultraviolet-A light for approximately 30 minutes. The combination of the riboflavin and the UV light triggers the creation of new cross-links between the collagen fibres, strengthening the cornea.

Step 4 — Bandage Contact Lens

A soft bandage contact lens is placed over the eye to protect the corneal surface while it heals. This is removed at a follow-up appointment after three to five days.

Recovery After CXL

The first few days after CXL involve some discomfort, light sensitivity, and blurred vision as the corneal surface heals. Pain relief and antibiotic and anti-inflammatory drops are prescribed. Vision may be temporarily worse than before the procedure and typically takes several months to stabilise. The full effect of cross-linking on halting progression is assessed over the following one to two years through regular corneal topography monitoring.

Why Patients Trust RGC Eye Hospital

• Experienced corneal specialists who assess each patient thoroughly before recommending CXL
• Careful pre-operative mapping of the cornea to confirm suitability and plan the procedure
• Close post-operative monitoring with corneal topography to confirm stabilisation
• Clear and honest communication about what CXL can and cannot achieve for your vision