Microstructural crimp of the lamina cribrosa and peripapillary sclera collagen fibers

Ning Jiun Jan, Celeste Gomez, Saundria Moed, Andrew P. Voorhees, Joel S. Schuman, Richard A. Bilonick, Ian A. Sigal

    Research output: Contribution to journalArticlepeer-review

    Abstract

    PURPOSE. Although collagen microstructural crimp is a major determinant of ocular biomechanics, no direct measurements of optic nerve head (ONH) crimp have been reported. Our goal was to characterize the crimp period of the lamina cribrosa (LC) and peripapillary sclera (PPS) at low and normal IOPs. METHODS. ONHs from 11 sheep eyes were fixed at 10-, 5-, or 0-mm Hg IOP and crimp periods measured manually from coronal cryosections imaged with polarized light microscopy (PLM). Using linear mixed-effect models, we characterized the LC and PPS periods, and how they varied with distance from the scleral canal edge. RESULTS. A total of 17,374 manual collagen crimp period measurements were obtained with high repeatability (1.9 lm) and reproducibility (4.7 μm). The periods were smaller (P < 0.001) and less variable in the LC than in the PPS: average (SD) of 13.8 (3.1) lm in the LC, and 31.0 (10.4) μm in the PPS. LC crimp period did not vary with distance from the scleral canal wall (P > 0.1). PPS period increased with the square root of the distance to the canal (P < 0.0001). CONCLUSIONS. Small, uniform crimp periods within the sheep LC and immediately adjacent PPS may indicate that these tissues are setup to prevent large or heterogeneous deformations that insult the neural tissues within the canal. An increasing more variable period with distance from the canal provides a smooth transition of mechanical properties that minimizes stress and strain concentrations.

    Original languageEnglish (US)
    Pages (from-to)3378-3388
    Number of pages11
    JournalInvestigative Ophthalmology and Visual Science
    Volume58
    Issue number9
    DOIs
    StatePublished - Jul 2017

    Keywords

    • Biomechanics
    • Collagen
    • Lamina cribrosa
    • Optic nerve head
    • Peripapillary sclera
    • Sclera
    • Scleral canal
    • Sheep

    ASJC Scopus subject areas

    • Ophthalmology
    • Sensory Systems
    • Cellular and Molecular Neuroscience

    Fingerprint Dive into the research topics of 'Microstructural crimp of the lamina cribrosa and peripapillary sclera collagen fibers'. Together they form a unique fingerprint.

    Cite this