Corneal Melting After Simultaneous Cairs Implantation & Corneal Cross Linking

To report a case of persistent epithelial defect and corneal melting following simultaneous femtosecond laser-assisted Corneal Allogenic Intracorneal Ring Segments (CAIRS) implantation and corneal cross-linking (CXL) in a patient with progressive keratoconus.

Cornea Department Zaldivar Institute 

A 36-year-old patient with progressive keratoconus underwent simultaneous CAIRS implantation and corneal cross-linking. A femtosecond laser was used to create the tunnel, pre-cut, preserved donor was dehydrated for 30 minutes before implantation. Following CAIRS implantation, epithelial debridement was performed, and dextran- riboflavin was instilled according to the Dressden protocol CXL for 5 minutes at 18 mW/cm² was performed. No intraoperative complications were described, at 72 hours, delayed epithelial healing was observed, with a persistent epithelial defect. Contact lens was applied, and topical insulin was added to the standard treatment. By postoperative day 20, the epithelial defect persisted, prompting the application of lyophilized amniotic membrane patches, the defect remained, leading to the detection of a superficial Bowman’s layer perforation with CAIRS exposure, the CAIRS segment was removed, and an amniotic membrane graft with tissue adhesive was placed. After 2 months of treatment, due corneal melting and impending perforation a sectoral conjunctival flap was performed. Microbiological cultures were performed and returned negative results, ruling out infectious keratitis as a cause of the complication. Additionally, systemic laboratory tests revealed positive rheumatoid arthritis antibodies in the initial screening, suggesting an underlying autoimmune component contributing to delayed wound healing.

Simultaneous CAIRS implantation and CXL may result in late complications such as corneal melting, particularly in patients with underlying systemic conditions. To minimize the risk of delayed epithelial healing and associated complications, a staged surgical approach is recommended instead of a combined procedure. Furthermore, systemic autoimmune screening should be considered in cases with unexplained postoperative complications.