title: Elastic modulus of orbicularis oculi muscle in normal humans, humans with Graves' eye disease, and cynomolgus monkeys.
abstract: We built an experimental apparatus to investigate the passive elastic characteristics of orbicularis oculi muscle and examined specimens from normal humans, humans with stable Graves' eye disease, and cynomolgus monkeys. Stress-strain curves were determined and found to be exponential. The elastic modulus (Young's modulus), analogous to the stiffness of the material, was calculated as a function of strain. Elastic modulus as a function of instantaneous stress was linear. Monkey elastic modulus values were determined, but did not allow meaningful interspecies comparison because of the small sample size. No significant difference was found between normal humans and humans with Graves' eye disease with respect to elastic modulus values.
authors.affiliation: Department of Ophthalmology, University of Toronto, Ontario, Canada.
authors.forename: J H
authors.initials: JH
authors.lastname: Oestreicher
authors.forename: B R
authors.initials: BR
authors.lastname: Frueh
mesh_terms: D000818:Animals; D004547:Elastic Tissue / Q000502:physiology; D004548:Elasticity; D006111:Graves Disease / Q000503:physiopathology*; D006801:Humans; D008252:Macaca fascicularis; D009126:Muscle Relaxation / Q000502:physiology; D009801:Oculomotor Muscles / Q000502:physiology*; D013314:Stress, Mechanical