Eberhard Spoerl1, Gregor Wollensak, Theo Seiler. 1. Department of Ophthalmology, Universitätsklinikum CGC, Fetscherstrasse 74, D-01307 Dresden, Germany. eberhard.spoerl@uniklinikum-dresden.de
Abstract
PURPOSE: Collagen-crosslinking using combined riboflavin/ UVA treatment has been developed by us as a new treatment for keratoconus by stiffening the collagenous matrix. Recently, we have started to use the same method for the treatment of corneal ulcers. The aim of the present study was to evaluate the influence of the crosslinking treatment on the resistance of the cornea against enzymatic degradation. METHODS: 60 enucleated porcine eyes were treated with the photosensitizer riboflavin and UVA-irradiation (370 nm; irradiance of 1, 2 or 3 mW/cm2) for 30 minutes and compared with 20 untreated control eyes. After crosslinking treatment, the corneal buttons were trephined and exposed to pepsin, trypsin and collagenase solutions. The extent of the corneal digestion was monitored daily. Selected cases were examined by light microscopy. RESULTS: The corneal buttons crosslinked with riboflavin/ UVA at 3 mW/cm2 were dissolved only by day 13 following pepsin digestion and by day 14 following collagenase treatment versus 6 days in the untreated control corneas. Digestion by trypsin was observed on day 5 in buttons crosslinked at 3 mW/cm2 compared to day 2 in the control corneas. Microscopically, a prolonged preservation especially of the anterior portion of the crosslinked corneas could be demonstrated. CONCLUSIONS: Photochemical crosslinking of the cornea using riboflavin and UVA results in a markedly increased resistance versus collagen digesting enzymes. The findings support the use of the new method in the treatment of corneal ulcers.
PURPOSE: Collagen-crosslinking using combined riboflavin/ UVA treatment has been developed by us as a new treatment for keratoconus by stiffening the collagenous matrix. Recently, we have started to use the same method for the treatment of corneal ulcers. The aim of the present study was to evaluate the influence of the crosslinking treatment on the resistance of the cornea against enzymatic degradation. METHODS: 60 enucleated porcine eyes were treated with the photosensitizer riboflavin and UVA-irradiation (370 nm; irradiance of 1, 2 or 3 mW/cm2) for 30 minutes and compared with 20 untreated control eyes. After crosslinking treatment, the corneal buttons were trephined and exposed to pepsin, trypsin and collagenase solutions. The extent of the corneal digestion was monitored daily. Selected cases were examined by light microscopy. RESULTS: The corneal buttons crosslinked with riboflavin/ UVA at 3 mW/cm2 were dissolved only by day 13 following pepsin digestion and by day 14 following collagenase treatment versus 6 days in the untreated control corneas. Digestion by trypsin was observed on day 5 in buttons crosslinked at 3 mW/cm2 compared to day 2 in the control corneas. Microscopically, a prolonged preservation especially of the anterior portion of the crosslinked corneas could be demonstrated. CONCLUSIONS: Photochemical crosslinking of the cornea using riboflavin and UVA results in a markedly increased resistance versus collagen digesting enzymes. The findings support the use of the new method in the treatment of corneal ulcers.
Authors: Elena Lanchares; María Angeles del Buey; José Angel Cristóbal; Laura Lavilla; Begoña Calvo Journal: Graefes Arch Clin Exp Ophthalmol Date: 2011-04-15 Impact factor: 3.117
Authors: Settimio Rossi; Carmine Santamaria; Rosa Boccia; Luigi De Rosa; Francesco Maria D'Alterio; Francesca Simonelli; Giuseppe De Rosa Journal: Int Ophthalmol Date: 2017-11-28 Impact factor: 2.031