title: Changes in scleral collagen organization in murine chronic experimental glaucoma.
abstract: OBJECTIVE
  The organization of scleral collagen helps to determine the eye's biomechanical response to intraocular pressure (IOP), and may therefore be important in glaucoma. This study provides a quantitative assessment of changes in scleral collagen fibril organization in bead-induced murine experimental glaucoma.
  
  
  METHODS
  Wide-angle X-ray scattering was used to study the effect of bead-induced glaucoma on posterior scleral collagen organization in one eye of 12 CD1 mice, with untreated fellow eyes serving as controls. Three collagen parameters were measured: the local preferred fibril directions, the degree of collagen anisotropy, and the total fibrillar collagen content.
  
  
  RESULTS
  The mouse sclera featured a largely circumferential orientation of fibrillar collagen with respect to the optic nerve head canal. Localized alteration to fibril orientations was evident in the inferior peripapillary sclera of bead-treated eyes. Collagen anisotropy was significantly (P<0.05) reduced in bead-treated eyes in the superior peripapillary (Treated: 43±8%;
  
  
  METHODS
  49±6%) and midposterior (Treated: 39±4%;
  
  
  METHODS
  43±4%) sclera, and in the peripapillary region overall (Treated: 43±6%;
  
  
  METHODS
  47±3%). No significant differences in total collagen content were found between groups.
  
  
  CONCLUSIONS
  Spatial changes in collagen fibril anisotropy occur in the posterior sclera of mice with bead-induced chronic IOP elevation and axonal damage. These results support the idea that dynamic changes in scleral form and structure play a role in the development of experimental glaucoma in mice, and potentially in human glaucoma.
authors.affiliation: Structural Biophysics Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom.
authors.forename: Jacek K
authors.initials: JK
authors.lastname: Pijanka
authors.affiliation: Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States.
authors.forename: Elizabeth C
authors.initials: EC
authors.lastname: Kimball
authors.affiliation: Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States.
authors.forename: Mary E
authors.initials: ME
authors.lastname: Pease
authors.affiliation: Structural Biophysics Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Abass
authors.affiliation: Diamond Light Source, Didcot, United Kingdom.
authors.forename: Thomas
authors.initials: T
authors.lastname: Sorensen
authors.affiliation: Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland, United States.
authors.forename: Thao D
authors.initials: TD
authors.lastname: Nguyen
authors.affiliation: Glaucoma Center of Excellence, Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, Maryland, United States.
authors.forename: Harry A
authors.initials: HA
authors.lastname: Quigley
authors.affiliation: Structural Biophysics Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom.
authors.forename: Craig
authors.initials: C
authors.lastname: Boote
mesh_terms: D000818:Animals; D016880:Anisotropy; D002908:Chronic Disease; D003094:Collagen / Q000737:chemistry*; D004195:Disease Models, Animal; D004548:Elasticity; D005901:Glaucoma / Q000378:metabolism* / Q000503:physiopathology; D007429:Intraocular Pressure; D051379:Mice; D012542:Scattering, Radiation; D012590:Sclera / Q000378:metabolism* / Q000503:physiopathology; D014965:X-Rays
chemical_list: D003094:Collagen
keywords: X-ray scattering; collagen; glaucoma; mouse; sclera