title: Three-dimensional arrangement of elastic fibers in the human corneal stroma.
abstract: The cornea is the main refracting lens in the eye. As part of the outer tunic it has to be resilient, a property conferred by the organisation of the constituent collagen. It also has to be sufficiently elastic to regain its exact shape when deformed, in order not to distort the retinal image. The basis of this elasticity is not fully understood. The purpose of this study was to characterise in three dimensions the arrangement and distribution of elastic fibers in the human corneal stroma, using serial block face scanning electron microscopy. We have demonstrated that there exists a complex network of elastic fibers that appear to originate in the sclera or limbus. These appear as elastic sheets in the limbus and peripheral cornea immediately above the trabecular meshwork which itself appears to extend above Descemet's membrane in the peripheral stroma. From these sheets, elastic fibers extend into the cornea; moving centrally they bifurcate and trifurcate into narrower fibers and are concentrated in the posterior stroma immediately above Descemet's membrane. We contend that elastic sheets will play an important role in the biomechanical deformation and recovery of the peripheral cornea. The network may also have practical implications for understanding the structural basis behind a number of corneal surgeries.
authors.affiliation: Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK.
authors.forename: Philip N
authors.initials: PN
authors.lastname: Lewis
authors.affiliation: Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK.
authors.forename: Tomas L
authors.initials: TL
authors.lastname: White
authors.affiliation: Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Young
authors.affiliation: Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK.
authors.forename: James S
authors.initials: JS
authors.lastname: Bell
authors.affiliation: Department of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL, UK.
authors.forename: C Peter
authors.initials: CP
authors.lastname: Winlove
authors.affiliation: Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff CF24 4HQ, UK. Electronic address: meekkm@cardiff.ac.uk.
authors.forename: Keith M
authors.initials: KM
authors.lastname: Meek
mesh_terms: D000368:Aged; D003094:Collagen / Q000378:metabolism / Q000648:ultrastructure; D003319:Corneal Stroma / Q000378:metabolism / Q000648:ultrastructure*; D004547:Elastic Tissue / Q000378:metabolism / Q000648:ultrastructure*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission
chemical_list: D003094:Collagen
keywords: Cornea; Elastic fibers; Glaucoma; Microfibrils; Ocular pulse; Pre-Descemet's layer; Trabecular meshwork