title: Evaluating the Effects of Riboflavin/UV-A and Rose-Bengal/Green Light Cross-Linking of the Rabbit Cornea by Noncontact Optical Coherence Elastography.
abstract: The purpose of this study was to use noncontact optical coherence elastography (OCE) to evaluate and compare changes in biomechanical properties that occurred in rabbit cornea in situ after corneal collagen cross-linking by either of two techniques: ultraviolet-A (UV-A)/riboflavin or rose-Bengal/green light.
  
  
  
  Low-amplitude (≤10 μm) elastic waves were induced in mature rabbit corneas by a focused air pulse. Elastic wave propagation was imaged by a phase-stabilized swept source OCE (PhS-SSOCE) system. Corneas were then cross-linked by either of two methods: UV-A/riboflavin (UV-CXL) or rose-Bengal/green light (RGX). Phase velocities of the elastic waves were fitted to a previously developed modified Rayleigh-Lamb frequency equation to obtain the viscoelasticity of the corneas before and after the cross-linking treatments. Micro-scale depth-resolved phase velocity distribution revealed the depth-wise heterogeneity of both cross-linking techniques.
  
  
  
  Under standard treatment settings, UV-CXL significantly increased the stiffness of the corneas by ∼47% (P < 0.05), but RGX did not produce statistically significant increases. The shear viscosities were unaffected by either cross-linking technique. The depth-wise phase velocities showed that UV-CXL affected the anterior ∼34% of the corneas, whereas RGX affected only the anterior ∼16% of the corneas.
  
  
  
  UV-CXL significantly strengthens the cornea, whereas RGX does not, and the effects of cross-linking by UV-CXL reach deeper into the cornea than cross-linking effects of RGX under similar conditions.
authors.affiliation: Department of Biomedical Engineering, University of Houston, Houston, Texas, United States.
authors.forename: Manmohan
authors.initials: M
authors.lastname: Singh
authors.affiliation: Department of Biomedical Engineering, University of Houston, Houston, Texas, United States.
authors.forename: Jiasong
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Biomedical Engineering, University of Houston, Houston, Texas, United States.
authors.forename: Zhaolong
authors.initials: Z
authors.lastname: Han
authors.affiliation: College of Optometry, University of Houston, Houston, Texas, United States.
authors.forename: Srilatha
authors.initials: S
authors.lastname: Vantipalli
authors.affiliation: Department of Biomedical Engineering, University of Houston, Houston, Texas, United States.
authors.forename: Chih-Hao
authors.initials: CH
authors.lastname: Liu
authors.affiliation: Department of Biomedical Engineering, University of Houston, Houston, Texas, United States.
authors.forename: Chen
authors.initials: C
authors.lastname: Wu
authors.affiliation: Department of Biomedical Engineering, University of Houston, Houston, Texas, United States.
authors.forename: Raksha
authors.initials: R
authors.lastname: Raghunathan
authors.affiliation: Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas, United States.
authors.forename: Salavat R
authors.initials: SR
authors.lastname: Aglyamov
authors.affiliation: School of Optometry, University of Alabama at Birmingham, Birmingham, Alabama, United States.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Twa
authors.affiliation: Department of Biomedical Engineering, University of Houston, Houston, Texas, United States 5Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk, Russia.
authors.forename: Kirill V
authors.initials: KV
authors.lastname: Larin
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D003094:Collagen / Q000494:pharmacology*; D003315:Cornea / Q000000981:diagnostic imaging* / Q000187:drug effects / Q000503:physiopathology; D003316:Corneal Diseases / Q000175:diagnosis / Q000503:physiopathology; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D004195:Disease Models, Animal; D004548:Elasticity; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005456:Fluorescent Dyes / Q000494:pharmacology; D017319:Photosensitizing Agents / Q000494:pharmacology; D011817:Rabbits; D012256:Riboflavin / Q000494:pharmacology*; D012395:Rose Bengal / Q000494:pharmacology*; D014466:Ultraviolet Rays
chemical_list: D003432:Cross-Linking Reagents; D005456:Fluorescent Dyes; D017319:Photosensitizing Agents; D012395:Rose Bengal; D003094:Collagen; D012256:Riboflavin