Highly effective 525 nm femtosecond laser crosslinking of collagen and strengthening of a human donor cornea. (13th December 2017)

• Record Type: Journal Article
• Authors: Shavkuta, B S; Gerasimov, M Y; Minaev, N V; Kuznetsova, D S; Dudenkova, V V; Mushkova, I A; Malyugin, B E; Kotova, S L; Timashev, P S; Kostenev, S V; Chichkov, B N; Bagratashvili, V N
• Is Part Of: Laser physics letters. Volume 15:Number 1(2018:Jan.)
• Publication Date: 2017-12-13
• Subjects: 525 nm femtosecond laser -- human cornea -- two-photon collagen crosslinking -- keratoconus -- riboflavin -- micromechanical properties; Lasers -- Periodicals; Physics -- Periodicals; 621.366
• DOI: 10.1088/1612-202X/aa963b
• Languages: English
• ISSNs: 1612-2011

Abstract

Abstract: A two-photon laser femtosecond crosslinking process at the wavelength of 525 nm was studied in a human donor cornea in the presence of riboflavin using two-photon optical microscopy and nanoindentation. It was shown that such an approach results in efficient crosslinking of the corneal collagen and a significant (three-fold) increase in the Young's modulus of the corneal structure. Application of a femtosecond laser with the wavelength of 525 nm allows a drastic enhancement of efficiency in the presence of riboflavin on human corneas and a 50-fold reduction of the laser treatment duration in comparison with the use of a femtosecond laser with the wavelength of 760 nm. We relate this effect to a significant growth in the coefficient of two-photon absorption due to the laser wavelength falling within the edge of the photoinitiator (riboflavin) absorption band. Our studies on a donor human cornea demonstrate the good potential for the clinical application of a femtosecond laser with the wavelength of 525 nm for increasing the cornea rigidity using the two-photon laser femtosecond crosslinking technique.