Posters

First results of a new method nonlinear optical femtosecond laser-induced collagen cross-linking of ex vivo human donor corneas

Poster Details

First Author: S.Kostenev RUSSIA

Co Author(s):    I. Mushkova   M. Gerasimov                 

Abstract Details

Purpose:

The aims of this study were to asses nonlinear optical (NLO) laser system for photo-activation of riboflavin in a local corneal volume and investigate appeared changes in biomechanical and biophysical properties of ex vivo human donor corneas

Setting:

S.N. Fyodorov Eye Microsurgery Complex, Moscow

Methods:

Twelve human donor corneas were obtained from the EyeTissue Bank, Moscow.The laser system included a higher repetition rate 525nm fs laser combined with spatial control instruments and low numerical aperture objective. For a clinical application simulation the samples were conventionally saturated in riboflavin and locked in the barron artificial chamber filed with corneal preservation solution.The data were evaluated using nanoindentometry, optical coherent tomography and two-photon excited fluorescence microscopy.

Results:

We found that the stiffness of the corneal area treated with NLO exposure improved and CXL patterns were detected with the TPEF microscopy. It is of importance that the Young’s moduli for the surface of the cornea that underwent the 2P-CXL process increased by more than three times, which indicated that photoinduced collagen crosslinking took place. The OCT data however were not as relevant as for the UV-A CXL and did not demonstrate the demarcation line and dehydratation of the corneal stroma.

Conclusions:

In this study we have demonstrated that NLO photo-activation of riboflavin induced the CXL in a local corneal volume following an individually designed spatial model. Thus new highly precise approach of nonlinear optical cornea collagen cross-linking might become a better method for further treatment of cornea ecstatic disorders.

Financial Disclosure:

None