Collagen Cross-linking in Keratoconus

Clinical Trial of Laser Custom Corneal Collagen Cross-Linking in Keratoconus

Optical Coherence Tomography (OCT) devices are non-contact instruments that can measure the depth of scars, other causes of cloudiness of the cornea, and degree of corneal thinning in patients with keratoconus. Laser Custom Corneal Collagen Cross-linking (CXL) significantly decreases corneal aberrations and improves vision. This study will use OCT-guided setting for the lasers used in the corneal smoothing portion of the laser custom CXL procedure to assess the affect on visual outcomes.

In the U.S., CXL and topography-guided laser ablation were approved independently, but not together. Another variation in technique involves the use of mitomycin-C (MMC), which is effective in reducing corneal haze after the laser surface ablation. Use of MMC during the laser custom CXL was associated with better outcomes, but in separate trials that could not be directly compared. This study will use OCT measurements to evaluate the magnitudes of direct and indirect laser actions after the procedure.

Inclusion Criteria:

• Diagnosis of keratoconus
• Minimum corneal thickness of 410 microns

Exclusion Criteria:

• Inability to maintain fixation for OCT imaging
• Inability to commit to required study visits
• Inability to give informed consent
• Eyes with concurrent retinal diseases, glaucoma, or other eye conditions that may limit the visual outcome after surgery
• Mature cataracts if found to limit visual potential to worse than 20/40