Marco Lombardo1, Norberto Micali2, Valentina Villari2, Sebastiano Serrao2, Giuseppe Pucci2, Riccardo Barberi2, Giuseppe Lombardo2. 1. From the Fondazione G.B. Bietti-IRCCS (M. Lombardo, Serrao), Vision Engineering Italy srl (G. Lombardo), Rome, Consiglio Nazionale delle Ricerche-Istituto per i Processi Chimico Fisici (Micali, Villari, G. Lombardo), Messina, and the Department of Physics (Pucci, Barberi), University of Calabria, Rende, Italy. Electronic address: mlombardo@visioeng.it. 2. From the Fondazione G.B. Bietti-IRCCS (M. Lombardo, Serrao), Vision Engineering Italy srl (G. Lombardo), Rome, Consiglio Nazionale delle Ricerche-Istituto per i Processi Chimico Fisici (Micali, Villari, G. Lombardo), Messina, and the Department of Physics (Pucci, Barberi), University of Calabria, Rende, Italy.
Abstract
PURPOSE: To evaluate the stromal concentration of 2 commercially available transepithelial riboflavin 0.1% solutions in human donor corneas with the use of spectrophotometry. SETTING: University of Calabria, Rende, Italy. DESIGN: Experimental study. METHODS: The absorbance spectra of 12 corneal tissues were measured in the 330 to 700 nm wavelength range using a purpose-designed spectrophotometry setup before and after transepithelial corneal soaking with a 15% dextran-enriched riboflavin 0.1% solution (n = 6) or a hypotonic dextran-free riboflavin 0.1% solution (n = 6). Both ophthalmic solutions contained ethylenediaminetetraacetic acid and trometamol as enhancers. In addition, 4 deepithelialized corneal tissues underwent stromal soaking with a 20% dextran-enriched riboflavin 0.1% solution and were used as controls. All the riboflavin solutions were applied topically for 30 minutes. The stromal concentration of riboflavin was quantified by analysis of absorbance spectra of the cornea collected before and after application of each solution. RESULTS: The mean stromal riboflavin concentration was 0.012% ± 0.003% (SD), 0.0005% ± 0.0003% (P < .001), and 0.004% ± 0.001% (P < .01) in tissues soaked with 20% dextran-enriched, 15% dextran-enriched, and hypotonic dextran-free solutions, respectively. The difference of stromal riboflavin concentration between the 2 transepithelial solutions was statistically significant (P < .01). CONCLUSIONS: Dextran-enriched solutions required complete corneal deepithelialization to permit effective stromal soaking with riboflavin. Nevertheless, riboflavin in hypotonic dextran-free solution with enhancers permeates across stroma through an intact epithelium. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.
PURPOSE: To evaluate the stromal concentration of 2 commercially available transepithelial riboflavin 0.1% solutions in humandonor corneas with the use of spectrophotometry. SETTING: University of Calabria, Rende, Italy. DESIGN: Experimental study. METHODS: The absorbance spectra of 12 corneal tissues were measured in the 330 to 700 nm wavelength range using a purpose-designed spectrophotometry setup before and after transepithelial corneal soaking with a 15% dextran-enriched riboflavin 0.1% solution (n = 6) or a hypotonicdextran-free riboflavin 0.1% solution (n = 6). Both ophthalmic solutions contained ethylenediaminetetraacetic acid and trometamol as enhancers. In addition, 4 deepithelialized corneal tissues underwent stromal soaking with a 20% dextran-enriched riboflavin 0.1% solution and were used as controls. All the riboflavin solutions were applied topically for 30 minutes. The stromal concentration of riboflavin was quantified by analysis of absorbance spectra of the cornea collected before and after application of each solution. RESULTS: The mean stromal riboflavin concentration was 0.012% ± 0.003% (SD), 0.0005% ± 0.0003% (P < .001), and 0.004% ± 0.001% (P < .01) in tissues soaked with 20% dextran-enriched, 15% dextran-enriched, and hypotonicdextran-free solutions, respectively. The difference of stromal riboflavin concentration between the 2 transepithelial solutions was statistically significant (P < .01). CONCLUSIONS:Dextran-enriched solutions required complete corneal deepithelialization to permit effective stromal soaking with riboflavin. Nevertheless, riboflavin in hypotonicdextran-free solution with enhancers permeates across stroma through an intact epithelium. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.
Authors: Jurriaan Brekelmans; Mor M Dickman; Shwetabh Verma; Samuel Arba-Mosquera; Ruth Goldschmidt; Alexandra Goz; Alexander Brandis; Tos T J M Berendschot; Isabelle E Y Saelens; Arie L Marcovich; Avigdor Scherz; Rudy M M A Nuijts Journal: Acta Ophthalmol Date: 2021-09-17 Impact factor: 3.988
Authors: Arie L Marcovich; Jurriaan Brekelmans; Alexander Brandis; Ilan Samish; Iddo Pinkas; Dina Preise; Keren Sasson; Ilan Feine; Alexandra Goz; Mor M Dickman; Rudy M M A Nuijts; Avigdor Scherz Journal: Transl Vis Sci Technol Date: 2020-05-11 Impact factor: 3.283