title: An experimental study on collagen content and biomechanical properties of sclera after posterior sclera reinforcement.
abstract: BACKGROUND
  The development of pathological myopia is associated with reduced scleral collagen accumulation, scleral thinning, and loss of scleral tissue, in both humans and animal models. Posterior scleral reinforcement (PSR) was considered as an effective way for treating pathological myopia. Yet it is not well understood the possible role of collagen on the sclera reinforcement mechanisms in the PSR surgery.
  
  
  METHODS
  PSR surgery was performed on the normal adult New Zealand white rabbits eyes. Human sclera was used as reinforcement materials. At 1, 2, 3, 6, 9 months after the PSR surgery, scleral hydroxyproline (Hyp) synthesis and collagen fibers arrangement were determined by enzymolysic hydrolysis assay and histological morphology technique. An Instron test machine was used to investigate the elastic modulus of sclera.
  
  
  RESULTS
  It was found that the elastic modulus and Hyp content of reinforced sclera were lower at first month after surgery, and then gradually up to physiological level in the following months. Those two indexes were close to that of the normal control groups at 9 months.
  
  
  CONCLUSIONS
  These findings indicate that sclera elastic modulus was associated with both change of Hyp content and collagen fibers arrangement after PSR. The therapeutic effect of PSR surgery was confirmed not only from biological but also biomechanical aspects.
authors.affiliation: Institute of Applied Mechanics and Biomedical Engineering, Taiyuan University of Technology, Taiyuan 030024, China. chenweiyi@tyut.edu.cn
authors.forename: Chen
authors.initials: C
authors.lastname: Weiyi
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Wang
authors.forename: Chaoying
authors.initials: C
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Tao
authors.forename: Xiaona
authors.initials: X
authors.lastname: Li
authors.forename: Quanyou
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000818:Animals; D003094:Collagen / Q000502:physiology*; D004548:Elasticity; D006244:Hardness; D006801:Humans; D006909:Hydroxyproline / Q000502:physiology*; D011817:Rabbits; D012590:Sclera / Q000502:physiology* / Q000637:transplantation*; D016639:Scleroplasty / Q000295:instrumentation* / Q000379:methods*; D013314:Stress, Mechanical
chemical_list: D003094:Collagen; D006909:Hydroxyproline