title: Quantitative analysis of three-dimensional fibrillar collagen microstructure within the normal, aged and glaucomatous human optic nerve head.
abstract: The aim of this study was to quantify connective tissue fibre orientation and alignment in young, old and glaucomatous human optic nerve heads (ONH) to understand ONH microstructure and predisposition to glaucomatous optic neuropathy. Transverse (seven healthy, three glaucomatous) and longitudinal (14 healthy) human ONH cryosections were imaged by both second harmonic generation microscopy and small angle light scattering (SALS) in order to quantify preferred fibre orientation (PFO) and degree of fibre alignment (DOFA). DOFA was highest within the peripapillary sclera (ppsclera), with relatively low values in the lamina cribrosa (LC). Elderly ppsclera DOFA was higher than that in young ppsclera (p < 0.00007), and generally higher than in glaucoma ppsclera. In all LCs, a majority of fibres had preferential orientation horizontally across the nasal-temporal axis. In all glaucomatous LCs, PFO was significantly different from controls in a minimum of seven out of 12 LC regions (p < 0.05). Additionally, higher fibre alignment was observed in the glaucomatous inferior-temporal LC (p < 0.017). The differences between young and elderly ONH fibre alignment within regions suggest that age-related microstructural changes occur within the structure. The additional differences in fibre alignment observed within the glaucomatous LC may reflect an inherent susceptibility to glaucomatous optic neuropathy, or may be a consequence of ONH remodelling and/or collapse.
authors: Optic Nerve Group, Cardiff Centre for Vision Science, Cardiff University, Cardiff, UK Bioimaging Labs, Cardiff University, Cardiff, UK Cardiff Institute for Tissue Engineering and Repair, Cardiff University, Cardiff, UK.
authors: H J
authors: HJ
authors: Jones
authors: In vivo Biomechanics Laboratory, Department of Biomedical Engineering, National University of Singapore, Singapore Singapore Eye Research Institute, Singapore National Eye Centre, Singapore.
authors: M J
authors: MJ
authors: Girard
authors: Cardiff Institute for Tissue Engineering and Repair, Cardiff University, Cardiff, UK.
authors: N
authors: N
authors: White
authors: Department of Ophthalmology, Mayo Clinic, Rochester, NY, USA.
authors: M P
authors: MP
authors: Fautsch
authors: Optic Nerve Group, Cardiff Centre for Vision Science, Cardiff University, Cardiff, UK.
authors: J E
authors: JE
authors: Morgan
authors: Georgia Institute of Technology and Emory, University School of Medicine, Atlanta, GA, USA Department of Bioengineering, Imperial College, London, UK.
authors: C R
authors: CR
authors: Ethier
authors: Optic Nerve Group, Cardiff Centre for Vision Science, Cardiff University, Cardiff, UK Bioimaging Labs, Cardiff University, Cardiff, UK Cardiff Institute for Tissue Engineering and Repair, Cardiff University, Cardiff, UK albonj@cardiff.ac.uk.
authors: J
authors: http://orcid.org/0000-0002-3029-8245
authors: J
authors: Albon
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D024022:Fibrillar Collagens / Q000648:ultrastructure*; D005901:Glaucoma / Q000473:pathology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D008853:Microscopy / Q000379:methods*; D008968:Molecular Conformation; D057054:Molecular Imaging / Q000379:methods; D009898:Optic Disk / Q000473:pathology / Q000648:ultrastructure*; D015203:Reproducibility of Results; D053838:Scattering, Small Angle; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D024022:Fibrillar Collagens
keywords: connective tissue; fibre orientation and alignment; glaucoma; optic nerve head; second harmonic generation; small angle light scattering