Posters

Confocal microscopy evaluation of stromal fluorescence intensity after standard and iontophoresis corneal cross-linking

Poster Details

First Author: M.Lanzini ITALY

Co Author(s):    C. Curcio   R. Calienno   M. Colasante   E. Spoerl   R. Turilli   L. Mastropasqua     

Abstract Details

Purpose:

Aim of this study is to determine differences in stromal riboflavin fluorescence intensity after iontophoresis imbibition and different exposure to UVA sources or standard epi-off procedures in human cadaver corneas and to correlate stromal fluorescence intensity to corneal biomechanical resistance.

Setting:

Ophthalmic Clinic. G d'Annunzio University. Chieti-Pescara. Italy

Methods:

For confocal microscopy study 15 human cadaver corneas were examined. 3 served as control(group 1), 3 were soaked with iontophoresis procedure(group 2), 3 were treated with standard technique(group 3), 6 underwent iontophoresis imbibition and 3 were irradiated for 30 minutes with 3 mW/cm2 UVA(group 4) and 3 for 9 minutes at 10 mW/cm2 UVA(group 5). Confocal microscopy was performed to quantify the fluorescence intensity in the cornea at different stromal depth. For biomechanical study 30 human cadaver corneas were randomly divided in 5 groups and treated as previously described. Static stress-strain measurements of the corneas were performed.

Results:

Iontophoresis imbibition followed by 10mW/cm2 irradiation proved to increase stromal fluorescence into the cornea and significant difference were revealed between group 3 and 5 both at 100 (p=0.0171) and 250 µm (p=0.0024) of stromal depth. Biomechanical analysis showed an improvement of corneal resistance in tissues treated with iontophoresis imbibition and accelerated irradiation (10mW/cm²).

Conclusions:

Iontophoresis imbibition followed by accelerated UVA irradiation for 9 minutes at 10mW/cm2 increased the stromal fluorescence despite the presence of an intact epithelium and is related to an improvement of biomechanical resistance. This approach may represent a new strategy to achieve greater concentrations of riboflavin without removing corneal epithelium and improve clinical results while reducing the side effects of corneal cross-linking.

Financial Disclosure:

NONE