title: Noncontact Elastic Wave Imaging Optical Coherence Elastography for Evaluating Changes in Corneal Elasticity Due to Crosslinking.
abstract: The mechanical properties of tissues can provide valuable information about tissue integrity and health and can assist in detecting and monitoring the progression of diseases such as keratoconus. Optical coherence elastography (OCE) is a rapidly emerging technique, which can assess localized mechanical contrast in tissues with micrometer spatial resolution. In this work we present a noncontact method of optical coherence elastography to evaluate the changes in the mechanical properties of the cornea after UV-induced collagen cross-linking. A focused air-pulse induced a low amplitude (μm scale) elastic wave, which then propagated radially and was imaged in three dimensions by a phase-stabilized swept source optical coherence tomography (PhS-SSOCT) system. The elastic wave velocity was translated to Young's modulus in agar phantoms of various concentrations. Additionally, the speed of the elastic wave significantly changed in porcine cornea before and after UV-induced corneal collagen cross-linking (CXL). Moreover, different layers of the cornea, such as the anterior stroma, posterior stroma, and inner region, could be discerned from the phase velocities of the elastic wave. Therefore, because of noncontact excitation and imaging, this method may be useful forin vivodetection of ocular diseases such as keratoconus and evaluation of therapeutic interventions such as CXL.
authors.affiliation: Department of Biomedical Engineering at the University of Houston, Houston, TX 77204 USA.
authors.forename: Manmohan
authors.initials: M
authors.lastname: Singh
authors.affiliation: Department of Biomedical Engineering at the University of Houston, Houston, TX 77204 USA.
authors.forename: Jiasong
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Optometry at the University of Houston, Houston, TX 77204 USA.
authors.forename: Srilatha
authors.initials: S
authors.lastname: Vantipalli
authors.affiliation: Department of Molecular Physiology and Biophysics at Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030 USA.
authors.forename: Shang
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Biomedical Engineering at the University of Houston, Houston, TX 77204 USA.
authors.forename: Zhaolong
authors.initials: Z
authors.lastname: Han
authors.affiliation: Department of Biomedical Engineering at the University of Houston, Houston, TX 77004 USA.
authors.forename: Achuth
authors.initials: A
authors.lastname: Nair
authors.affiliation: Department of Biomedical Engineering, University of Texas at Austin, Austin, TX 78731 USA.
authors.forename: Salavat R
authors.initials: SR
authors.lastname: Aglyamov
authors.affiliation: School of Optometry at the University of Alabama at Birmingham, Birmingham, AL 35924.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Twa
authors.affiliation: Department of Biomedical Engineering at the University of Houston, Houston, TX 77004 USA and and the Interdisciplinary Laboratory of Biophotonics, Tomsk State University, Tomsk 634050, Russia, phone: 832-842-8834; fax: 713-743-0226.
authors.forename: Kirill V
authors.initials: KV
authors.lastname: Larin
keywords: Biomechanical properties; cornea; elasticity; optical coherence elastography