The combination of Corneal Allogenic Intrastromal Ring Segments (CAIRS) and corneal crosslinking (CXL) represents a transformative approach in the treatment of keratoconus. When used together, CAIRS reshapes the cornea for better optical quality, while CXL stabilizes the underlying disease. This combination can provide both functional and structural rehabilitation. By simultaneously addressing the cornea’s shape and biomechanical integrity,this dual strategy enhances visual outcomes and strengthens corneal stability, offering a comprehensive solution for patients with moderate to advanced keratoconus.

What Is CAIRS?

CAIRS is an advanced surgical procedure that involves the implantation of donor corneal tissue segments into the mid-layers of the patient’s cornea. These segments act like braces, helping reshape the cone and regularize the corneal surface, improving visual quality.

What Is Corneal Cross-Linking?

Corneal cross-linking (CXL) strengthens the cornea by creating new bonds between collagen fibres. This is achieved by applying riboflavin (vitamin B2) drops to the cornea followed by exposure to ultraviolet (UV) light. While CXL does not significantly reshape the cornea, it halts disease progression by improving corneal biomechanical stability. For patients with keratoconus, this means a lower risk of further corneal thinning and bulging.

How the combination works

Typically, the procedure is performed in two steps:

Step 1: CAIRS implantation : Donor corneal segments are inserted into stromal tunnels created using a femtosecond laser.

Step 2: CXL: Approximately 2-4 weeks after CAIRS, CXL is performed to halt progression of keratoconus. By implanting CAIRS segments first, this allows the cornea to be reshaped for improved optical quality. Once the cornea has been reshaped, cross-linking can then be used to lock in the new shape, stabilizing the bio mechanics and halting further progression.

Patient Selection and Considerations

While the combination therapy is promising, not all patients are suitable candidates. Ideal candidates generally have moderate to advanced keratoconus with documented progression, corneal thickness sufficient to safely perform CXL (typically greater than 400 microns), and no history of corneal infection or scarring that could complicate CAIRS implantation. A thorough preoperative evaluation, including corneal topography, pachymetry, and bio mechanical assessment, is essential to ensure optimal outcomes.

If you have keratoconus, contact Nexus Eyecare to find out whether a CAIRS + CXL strategy is right for you.