The Effect of Collagen Cross-Linking Procedure on the Material of Intracorneal Ring Segments

Abstract Purpose: To assess the potential impact of corneal crosslinking treatment (365 nm ultraviolet (UV)A irradiation with riboflavin) on the material properties of Intracorneal Rings Segments (ICRS). Materials and methods: Material properties were studied using FT-IR spectroscopy and UV-Vis spectroscopy. Rings were examined: (1) after installation of riboflavin solution, (2) after irradiation with UV-A light and (3) after instillation of riboflavin solution followed by instillation and coeval irradiation. The experiments followed the standard corneal cross-linking (CXL) protocol of corneal crosslinking treatment. Results: After instillation of riboflavin solution, a permanent intense yellow staining of the samples was observed. UV-Vis spectroscopy confirmed that a certain amount of riboflavin solution was absorbed into the samples after CXL procedure. FT-IR spectroscopic analysis showed alterations in the spectra of ICRS mainly at the 2800–3200 cm−1 spectral region [modification in band intensities of CH2 (2925 cm−1) and CH3 (2950 cm−1)]. Conclusions: Our results suggest crosslinking reaction in ICRS material. This should be taken into consideration prior to any CXL treatment of post ICRS-implanted cornea.

[1]  Aylin Kılıç,et al.  Riboflavin injection into the corneal channel for combined collagen crosslinking and intrastromal corneal ring segment implantation , 2012, Journal of cataract and refractive surgery.

[2]  T. Kottke,et al.  Infrared spectrum and absorption coefficient of the cofactor flavin in water , 2011 .

[3]  Yves Marechal,et al.  The molecular structure of liquid water delivered by absorption spectroscopy in the whole IR region completed with thermodynamics data , 2011 .

[4]  J. Alió,et al.  Cross-linking in progressive keratoconus using an epithelial debridement or intrastromal pocket technique after previous corneal ring segment implantation. , 2011, Journal of refractive surgery.

[5]  P. Tavan,et al.  Density Functional Theory Combined with Molecular Mechanics: The Infrared Spectra of Flavin in Solution † , 2011, Photochemistry and photobiology.

[6]  A. Daxer,et al.  Corneal Crosslinking and Visual Rehabilitation in Keratoconus in One Session Without Epithelial Debridement: New Technique , 2010, Cornea.

[7]  M. Jankov,et al.  Effect of treatment sequence in combined intrastromal corneal rings and corneal collagen crosslinking for keratoconus , 2009, Journal of cataract and refractive surgery.

[8]  H. Smaoui,et al.  Study of charge relaxations after thermal aging in poly (methyl methacrylate) , 2009 .

[9]  A. Kanellopoulos.  Collagen cross-linking in early keratoconus with riboflavin in a femtosecond laser-created pocket: initial clinical results. , 2009, Journal of refractive surgery.

[10]  V. Novikov,et al.  About mechanism of chitosan cross-linking with glutaraldehyde , 2009, Russian Journal of Bioorganic Chemistry.

[11]  M. Jankov,et al.  One-year results of intrastromal corneal ring segment implantation (KeraRing) using femtosecond laser in patients with keratoconus. , 2008, American journal of ophthalmology.

[12]  Nikolaos S. Tsiklis,et al.  Long-term follow-up of Intacs in keratoconus. , 2007, American journal of ophthalmology.

[13]  Munish Sharma,et al.  Effect of inferior‐segment Intacs with and without C3‐R on keratoconus , 2007, Journal of cataract and refractive surgery.

[14]  M. A. Shams El-Din,et al.  UV-laser-assisted degradation of poly(methyl methacrylate) , 2005 .

[15]  N. Nagai,et al.  Infrared analysis of depth profiles in UV-photochemical degradation of polymers , 2005 .

[16]  H. Zidan,et al.  Structural and optical properties of pure PMMA and metal chloride-doped PMMA films , 2005 .

[17]  G. Oster,et al.  Photochemistry of riboflavin , 1962, Experientia.

[18]  T. Seiler,et al.  Stress‐strain measurements of human and porcine corneas after riboflavin–ultraviolet‐A‐induced cross‐linking , 2003, Journal of cataract and refractive surgery.

[19]  T. Seiler,et al.  Riboflavin/ultraviolet-a-induced collagen crosslinking for the treatment of keratoconus. , 2003, American journal of ophthalmology.

[20]  T. Corralesa,et al.  Free radical macrophotoinitiators : an overview on recent advances , 2003 .

[21]  J Colin,et al.  Correcting keratoconus with intracorneal rings. , 2000, Journal of cataract and refractive surgery.

[22]  Carsten Wochnowski,et al.  UV–laser-assisted modification of the optical properties of polymethylmethacrylate , 2000 .

[23]  Olgun Güven,et al.  UV degradation of poly(methyl methacrylate) and its vinyltriethoxysilane containing copolymers , 1999 .

[24]  W. Mäntele,et al.  ATP-Induced phosphorylation of the sarcoplasmic reticulum Ca2+ ATPase: molecular interpretation of infrared difference spectra. , 1998, Biophysical journal.

[25]  E. Spoerl,et al.  Induction of cross-links in corneal tissue. , 1998, Experimental eye research.

[26]  B. Lendl,et al.  Modulation of the pH in the Determination of Phosphate With Flow Injection and Fourier Transform Infrared Detection , 1997 .

[27]  Nicholas S. Nogar,et al.  Mass spectroscopic identification of wavelength dependent UV laser photoablation fragments from polymethylmethacrylate , 1986 .

[28]  R. Srinivasan,et al.  Dynamics of UV laser ablation of organic polymer surfaces , 1986 .

[29]  H. Philipp,et al.  Optical absorption of some polymers in the region 240-170 nm , 1986 .

[30]  Irving Lipschitz,et al.  The Vibrational Spectrum of Poly(Methyl Methacrylate): A Review , 1982 .

[31]  J. Koenig,et al.  Carbon–hydrogen stretching and bending vibrations in the Raman spectra of poly (methylmethacrylate) , 1980 .

[32]  H. Hiraoka,et al.  Radiation chemistry of poly(methacrylates) , 1977 .