PURPOSE: The aim of this study was to develop a modified ex vivo corneal cross-linking method that increases stromal resistance to enzymatic degradation for use as a carrier for the Boston keratoprosthesis. METHODS: Ex vivo cross-linking of human corneas was performed using Barron artificial anterior chambers. The corneas were deepithelialized, pretreated with riboflavin solution (0.1% riboflavin/20% dextran), and irradiated with ultraviolet A (UV-A) light (λ = 370 nm, irradiance = 3 mW/cm) for various durations. The combined effect of UV-A and gamma (γ) irradiation was also assessed using the commercially available γ-irradiated corneal donors. The corneas were then trephined and incubated at 37°C with 0.3% collagenase A solution. The time to dissolution of each cornea was compared across treatments. RESULTS: Deepithelialized corneas (no UV light, no riboflavin) dissolved in 5.8 ± 0.6 hours. Cross-linked corneas demonstrated increased resistance to dissolution, with a time to dissolution of 17.8 ± 2.6 hours (P < 0.0001). The corneal tissues' resistance to collagenase increased with longer UV-A exposure, reaching a plateau at 30 minutes. Cross-linking both the anterior and posterior corneas did not provide added resistance when compared with cross-linking the anterior corneas only (P > 0.05). γ-irradiated corneas dissolved as readily as deepithelialized controls regardless of whether they were further cross-linked (5.6 ± 1.2 hours) or not (6.1 ± 0.6 hours) (P = 0.43). CONCLUSIONS: Collagen cross-linking of the deepithelialized anterior corneal surface for 30 minutes conferred optimal resistance to in vitro keratolysis by collagenase A.
PURPOSE: The aim of this study was to develop a modified ex vivo corneal cross-linking method that increases stromal resistance to enzymatic degradation for use as a carrier for the Boston keratoprosthesis. METHODS: Ex vivo cross-linking of human corneas was performed using Barron artificial anterior chambers. The corneas were deepithelialized, pretreated with riboflavin solution (0.1% riboflavin/20% dextran), and irradiated with ultraviolet A (UV-A) light (λ = 370 nm, irradiance = 3 mW/cm) for various durations. The combined effect of UV-A and gamma (γ) irradiation was also assessed using the commercially available γ-irradiated corneal donors. The corneas were then trephined and incubated at 37°C with 0.3% collagenase A solution. The time to dissolution of each cornea was compared across treatments. RESULTS: Deepithelialized corneas (no UV light, no riboflavin) dissolved in 5.8 ± 0.6 hours. Cross-linked corneas demonstrated increased resistance to dissolution, with a time to dissolution of 17.8 ± 2.6 hours (P < 0.0001). The corneal tissues' resistance to collagenase increased with longer UV-A exposure, reaching a plateau at 30 minutes. Cross-linking both the anterior and posterior corneas did not provide added resistance when compared with cross-linking the anterior corneas only (P > 0.05). γ-irradiated corneas dissolved as readily as deepithelialized controls regardless of whether they were further cross-linked (5.6 ± 1.2 hours) or not (6.1 ± 0.6 hours) (P = 0.43). CONCLUSIONS: Collagen cross-linking of the deepithelialized anterior corneal surface for 30 minutes conferred optimal resistance to in vitro keratolysis by collagenase A.
Authors: Lance J Kugler; Shawna Hill; Dora Sztipanovits; Helen Boerman; Tracy Schroeder Swartz; Ming X Wang Journal: Cornea Date: 2011-09 Impact factor: 2.651
Authors: Joseph B Ciolino; Michael W Belin; Amit Todani; Khalid Al-Arfaj; Christopher J Rudnisky Journal: Ophthalmology Date: 2013-03-15 Impact factor: 12.079
Authors: Alja Crnej; Masahiro Omoto; Thomas H Dohlman; Claes H Dohlman; Reza Dana Journal: Invest Ophthalmol Vis Sci Date: 2014-12-16 Impact factor: 4.799
Authors: Naveen Radhakrishnan; Venkatesh N Prajna; Lalitha S Prajna; Anitha Venugopal; Shivanandha Narayana; Revathi Rajaraman; Guillermo Amescua; Travis C Porco; Thomas M Lietman; Jennifer Rose-Nussbaumer Journal: BMJ Open Ophthalmol Date: 2021-11-29
Authors: Jurriaan Brekelmans; Judith Veugen; Koen Rieff; Mor M Dickman; Alexa Goz; Petra Wolffs; Alexander Brandis; Tos T J M Berendschot; Rudy M M A Nuijts; Avigdor Scherz; Arie L Marcovich Journal: Transl Vis Sci Technol Date: 2020-09-03 Impact factor: 3.283