Dehydration And Rehydration Dynamics Of Porcine Corneal Allogenic Intrastromal Ring Segments Following Ultra-High-Fluence Extracorporeal Cross-Linking
Published 2026 - 44th Congress of the ESCRS
Reference: FP02.10 | Type: Free paper | DOI: 10.82333/xqcy-a021
Authors: Mr Léonard Kollros* 1 , Craig Boote 2 , Keith M. Meek 2 , Sally Hayes 2 , Mark Hillen 3 , Emilio A. Torres-Netto 3 , M. Enes Aydemir 3 , Shady T. Awwad 4 , Farhad Hafezi 3
1ELZA Institute,Zurich,Switzerland;School of Optometry & Vision Sciences,Cardiff University,Cardiff,United Kingdom;Institute of Optometry,University of Applied Sciences and Arts Northwestern Switzerland (FHNW),Olten,Switzerland;Lorella & Léonard OPTIC,Biel/Bienne,Switzerland, 2School of Optometry & Vision Sciences,Cardiff University,Cardiff,United Kingdom, 3ELZA Institute,Zurich,Switzerland, 4Department of Ophthalmology,American University of Beirut Medical Center,Beirut,Lebanon
Purpose
To evaluate the effect of extracorporeal ultra-high-fluence corneal cross-linking on dehydration and rehydration behavior of porcine stromal ring segments prepared for corneal allogenic intrastromal ring segment (CAIRS) implantation.
Setting
Experimental laboratory study conducted at the ELZA Institute, Zurich, Switzerland.
Methods
Forty-eight freshly enucleated porcine corneas were used to prepare stromal ring segments. Segments were randomly assigned to three groups: control (no UV), extracorporeal CXL 30 J/cm², and extracorporeal CXL 60 J/cm² (n=32 per group). Intervention groups were soaked in 0.1% riboflavin prior to UV-A irradiation (365 nm, 30 mW/cm²). All groups underwent a standardized 45-minute dehydration phase followed by 10-minute rehydration with balanced salt solution. Thickness measurements were obtained at baseline, post-dehydration, and post-rehydration using calibrated digital imaging and ImageJ analysis. Non-parametric statistical testing was applied (p<0.05).
Results
Baseline thickness did not differ significantly between groups. Both cross-linked groups demonstrated significantly greater dehydration compared to controls (30 J: p=0.0032; 60 J: p=0.0003). Rehydration was significantly reduced in both cross-linked groups relative to controls (30 J: p=5.46×10⁻⁶; 60 J: p=0.0011). No statistically significant difference was observed between the 30 J/cm² and 60 J/cm² groups. Ultra-high-fluence cross-linking resulted in thinner segments with delayed re-expansion kinetics.
Conclusions
Extracorporeal ultra-high-fluence cross-linking significantly enhances dehydration and reduces rehydration of corneal stromal ring segments ex vivo. These effects may improve intraoperative handling and extend the surgical implantation window in CAIRS procedures. No additional dehydration benefit was observed between 30 J/cm² and 60 J/cm² protocols. Further in vivo studies are required to determine long-term biomechanical and clinical implications.