Posters

Biomechanical comparison of enzymatic digestion resistance of 30mW/cm2 to 45Mw/cm2 fluence CXL, and to no-CXL: an ex-vivo LASIK combined with CXL study

Poster Details

First Author: G. Pamel GREECE

Co Author(s):    A. Kanellopoulos                    

Abstract Details

Purpose:

To evaluate ex-vivo biomechanical behavior by enzymatic digestion resistance differences between myopic LASIK combined with very high fluence in-situ cross-linking (CXL) for fluences of 30 and 45 mW/cm2 , also compared to standard myopic LASIK.

Setting:

the Laservision Clinical and Research Institute, Athens, Greece

Methods:

The study involved ten human donor corneas, subjected to -8.50 D myopic LASIK simulated treatment. Half-area of the cornea was subsequently subjected to adjuvant in-situ CXL, employing two different fluence settings (group-A, 30 mW/cm2 and in group-B, 45 mW/cm2). The non-CXL parts served as controls. Stoma and flap specimens were tested separately for resistance to enzymatic (collagenase-A) digestion, a metric for the evaluation of CXL effect.

Results:

The mean time to complete dissolution of the stroma specimens in group-A (CXL 30 mW/cm2 applied for 120 seconds) was 102±8 minutes for the CXL-halves, and 80±5 minutes for the non-CXL control halves. The relative difference between sample and control (Δ, expressed as %) was +27% (p =0.012). The mean time to complete dissolution of the stroma specimens in group-B (CXL 45 mW/cm2 for 80 seconds) was 91±8 minutes for the CXL-halves, and 84±8 minutes for the non-CXL control halves. Δ was +9% (p =0.347). There was no statistically significant difference noted in the flap specimens.

Conclusions:

This ex-vivo human corneal study indicates that enzymatic digestion resistance of in-situ CXL achieved with simultaneous myopic LASIK achieves statistically significant increase with the uses of fluence of 30 mW/cm2, and not with 45mW. /cm2

Financial Disclosure:

NONE