title: The contribution of glycosaminoglycans to the mechanical behaviour of the posterior human sclera.
abstract: We characterized the structural and mechanical changes after experimental digestion of sulfated glycosaminoglycans (s-GAGs) in the human posterior sclera, using ultrasound thickness measurements and an inflation test with three-dimensional digital image correlation (3D-DIC). Each scleral specimen was first incubated in a buffer solution to return to full hydration, inflation tested, treated in a buffer solution with chondroitinase ABC (ChABC), then inflation tested again. After each test series, the thickness of eight locations was measured. After enzymatic treatment, the average scleral thickness decreased by 13.3% (p < 0.001) and there was a stiffer overall stress-strain response (p < 0.05). The stress-strain response showed a statistically significant increase in the low-pressure stiffness, high-pressure stiffness and hysteresis. Thus, s-GAGs play a measurable role in the mechanical behaviour of the posterior human sclera.
authors.affiliation: Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA barbara.murienne@gmail.com.
authors.forename: Barbara J
authors.identifier: 0000-0003-1841-8803
authors.initials: BJ
authors.lastname: Murienne
authors.affiliation: Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Chen
authors.affiliation: Glaucoma Center of Excellence, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Harry A
authors.initials: HA
authors.lastname: Quigley
authors.affiliation: Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Thao D
authors.initials: TD
authors.lastname: Nguyen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019765:Chondroitin ABC Lyase / Q000737:chemistry; D006025:Glycosaminoglycans / Q000737:chemistry*; D006801:Humans; D008297:Male; D012590:Sclera / Q000737:chemistry*; D013314:Stress, Mechanical
chemical_list: D006025:Glycosaminoglycans; D019765:Chondroitin ABC Lyase
keywords: chondroitinase ABC; glaucoma; glycosaminoglycans; mechanical testing; myopia; sclera