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Age-Related Variation in the Biomechanical and Structural Properties of the Corneo-Scleral Tunic

  • Brendan Geraghty
  • Charles Whitford
  • Craig Boote
  • Riaz Akhtar
  • Ahmed Elsheikh
Chapter
Part of the Engineering Materials and Processes book series (EMP)

Abstract

With increasing age, the mechanical performance of the cornea and sclera is impaired due to structural changes in the major structural proteins, namely collagens , proteoglycans and elastin. In addition, the level of hydration in the ocular tunic decreases over time. These structural changes profoundly impact on the biomechanical properties of the corneo-scleral tunic. This chapter focuses on the structural and biomechanical changes that occur in the corneo-scleral tunic with age. The techniques that are utilized in order to determine the mechanical properties of both the cornea and sclera are discussed, and a comprehensive review of studies which have characterized age-related changes in ocular biomechanics are presented. The cornea is found to increase in stiffness with age and all the characteristics of viscoelastic behavior (creep , stress-relaxation and hysteresis) decrease with age. Similarly, the stiffness of the sclera increases markedly with age although the reported magnitude of stiffening varies significantly from one study to another. This may be related to variations amongst the different techniques that have been utilized. Increased stiffening in the cornea and the sclera with age is strongly associated with the increase in collagen crosslinking that occurs as part of the natural aging process.

Keywords

Collagen Fibril Central Corneal Thickness Tangent Modulus Lamina Cribrosa Biomechanical Behavior 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  • Brendan Geraghty
    • 1
  • Charles Whitford
    • 1
  • Craig Boote
    • 2
  • Riaz Akhtar
    • 1
  • Ahmed Elsheikh
    • 1
    • 3
  1. 1.Centre for Materials and Structures, School of EngineeringUniversity of LiverpoolLiverpoolUK
  2. 2.School of Optometry and Vision ScienceUniversity of CardiffCardiffUK
  3. 3.National Institute for Health Research (NIHR), Biomedical Research CentreMoorfields Eye Hospital NHS Foundation Trust and UCL Institute of OphthalmologyLondonUK

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