title: Indentation of poroviscoelastic vocal fold tissue using an atomic force microscope.
abstract: The elastic properties of the vocal folds (VFs) vary as a function of depth relative to the epithelial surface. The poroelastic anisotropic properties of porcine VFs, at various depths, were measured using atomic force microscopy (AFM)-based indentation. The minimum tip diameter to effectively capture the local properties was found to be 25µm, based on nonlinear laser scanning microscopy data and image analysis. The effects of AFM tip dimensions and AFM cantilever stiffness were systematically investigated. The indentation tests were performed along the sagittal and coronal planes for an evaluation of the VF anisotropy. Hertzian contact theory was used along with the governing equations of linear poroelasticity to calculate the diffusivity coefficient of the tissue from AFM indentation creep testing. The permeability coefficient of the porcine VF was found to be 1.80±0.32×10(-15)m(4)/Ns.
authors.affiliation: Biomechanics Laboratory, Department of Mechanical Engineering, McGill University, 817 Rue Sherbrooke Ouest, Montreal, Que., Canada H3A 0C3.
authors.forename: Hossein K
authors.initials: HK
authors.lastname: Heris
authors.forename: Amir K
authors.initials: AK
authors.lastname: Miri
authors.forename: Umakanta
authors.initials: U
authors.lastname: Tripathy
authors.forename: Francois
authors.initials: F
authors.lastname: Barthelat
authors.forename: Luc
authors.initials: L
authors.lastname: Mongeau
mesh_terms: D000818:Animals; D004548:Elasticity; D006244:Hardness; D008422:Materials Testing; D018625:Microscopy, Atomic Force; D010539:Permeability; D013552:Swine; D014783:Viscosity; D014827:Vocal Cords / Q000166:cytology*
keywords: Anisotropy; Atomic force microscopy; Indentation; Nonlinear optics; Permeability; Vocal folds