title: Optical coherence elastography for evaluating customized riboflavin/UV-A corneal collagen crosslinking.
abstract: UV-induced collagen cross-linking is a promising treatment for keratoconus that stiffens corneal tissue and prevents further degeneration. Since keratoconus is generally localized, the efficacy of collagen cross-linking (CXL) treatments could be improved by stiffening only the weakened parts of the cornea. Here, we demonstrate that optical coherence elastography (OCE) can spatially resolve transverse variations in corneal stiffness. A short duration ( ? 1 ?? ms ) focused air-pulse induced low amplitude ( ? 10 ?? ? m ) deformations in the samples that were detected using a phase-stabilized optical coherence tomography system. A two-dimensional map of material stiffness was generated by measuring the damped natural frequency (DNF) of the air-pulse induced response at various transverse locations of a heterogeneous phantom mimicking a customized CXL treatment. After validation on the phantoms, similar OCE measurements were made on spatially selective CXL-treated in situ rabbit corneas. The results showed that this technique was able to clearly distinguish the untreated and CXL-treated regions of the cornea, where CXL increased the DNF of the cornea by ? 51 % . Due to the noncontact nature and minimal excitation force, this technique may be valuable for in vivo assessments of corneal biomechanical properties.
authors.affiliation: University of Houston, Biomedical Engineering, 3517 Cullen Boulevard, Room 2027, Houston, Texas 77204, United States.
authors.forename: Manmohan
authors.initials: M
authors.lastname: Singh
authors.affiliation: University of Houston, Biomedical Engineering, 3517 Cullen Boulevard, Room 2027, Houston, Texas 77204, United States.
authors.forename: Jiasong
authors.initials: J
authors.lastname: Li
authors.affiliation: University of Houston, Department of Optometry, 4901 Calhoun Road, Houston, Texas 77204, United States.
authors.forename: Srilatha
authors.initials: S
authors.lastname: Vantipalli
authors.affiliation: University of Houston, Biomedical Engineering, 3517 Cullen Boulevard, Room 2027, Houston, Texas 77204, United States.
authors.forename: Zhaolong
authors.initials: Z
authors.lastname: Han
authors.affiliation: University of Houston, Biomedical Engineering, 3517 Cullen Boulevard, Room 2027, Houston, Texas 77204, United StatescBaylor College of Medicine, Molecular Physiology and Biophysics, One Baylor Plaza, Houston, Texas 77030, United StatesdSamara State Aerospace University, Electrical and Computer Engineering, 34, Moskovskoye shosse, Samara 443086, Russia.
authors.forename: Kirill V
authors.initials: KV
authors.lastname: Larin
authors.affiliation: University of Alabama at Birmingham, School of Optometry, 1716 University Boulevard, Birmingham, Alabama 35233, United States.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Twa
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D003094:Collagen / Q000737:chemistry*; D003315:Cornea / Q000737:chemistry* / Q000378:metabolism*; D054459:Elasticity Imaging Techniques; D007640:Keratoconus / Q000628:therapy; D011817:Rabbits; D012256:Riboflavin / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D003094:Collagen; D012256:Riboflavin