title: The zonules selectively alter the shape of the lens during accommodation based on the location of their anchorage points.
abstract: OBJECTIVE
  To determine the role of anterior and posterior zonular tension on the optomechanical lens response during accommodation simulation.
  
  
  METHODS
  Ten eyes from nine hamadryas baboons (4.9 ± 0.7 years) and 20 eyes from 18 cynomolgus monkeys (5.4 ± 0.3 years) were dissected, leaving the lens, zonules, ciliary body, hyaloid membrane, anterior vitreous, and a segmented scleral rim intact. The lens preparation was mounted in a lens stretcher, and the outer scleral shell was displaced radially in a stepwise fashion. The load, lens, and ciliary body diameters, lens power, lens thickness, and the anterior and posterior radius of curvature were measured during stretching. The zonular fibers attached to either the posterior or anterior lens surface were then carefully transected and the experiment was repeated. Zonular transection was confirmed in four eyes via laser scanning confocal microscopy after immunostaining. The effect of zonular transection on the tissue response to stretching was quantified.
  
  
  RESULTS
  Without anterior zonules, 48% and 97% of the changes in anterior and posterior radii are retained. Without posterior zonules, 81% and 67% of the changes in anterior and posterior radii are retained. The changes in lens shape were reduced after transecting either the anterior or posterior zonules; however, both surfaces still changed shape.
  
  
  CONCLUSIONS
  While either the anterior or posterior zonules alone are capable of changing the shape of both lens surfaces, the anterior zonules have a greater effect on the anterior lens surface, and the posterior zonules have a greater effect on the posterior lens surface.
authors.affiliation: Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, Florida, United States.
authors.forename: Derek
authors.initials: D
authors.lastname: Nankivil
authors.affiliation: Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, Florida, United States Biomedical Optics and Laser Laboratory, Department of Biomedical Engineering, University of Miami, Coral Gables, Florida, United States.
authors.forename: Bianca
authors.initials: B
authors.lastname: Maceo Heilman
authors.affiliation: Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, Florida, United States Biomedical Optics and Laser Laboratory, Department of Biomedical Engineering, University of Miami, Coral Gables, Florida, United States.
authors.forename: Heather
authors.initials: H
authors.lastname: Durkee
authors.affiliation: Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, Florida, United States Biomedical Optics and Laser Laboratory, Department of Biomedical Engineering, University of Miami, Coral Gables, Florida, United States.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Manns
authors.affiliation: Vision Cooperative Research Centre, Brien Holden Vision Institute, University of New South Wales, Sydney, Australia.
authors.forename: Klaus
authors.initials: K
authors.lastname: Ehrmann
authors.affiliation: Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, Florida, United States.
authors.forename: Shawn
authors.initials: S
authors.lastname: Kelly
authors.affiliation: Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, Florida, United States.
authors.forename: Esdras
authors.initials: E
authors.lastname: Arrieta-Quintero
authors.affiliation: Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, Florida, United States.
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Parel
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology*; D000818:Animals; D002924:Ciliary Body / Q000502:physiology*; D007908:Lens, Crystalline / Q000502:physiology*; D008252:Macaca fascicularis; D009130:Muscle, Smooth / Q000503:physiopathology; D055620:Optical Phenomena; D048529:Papio hamadryas
keywords: accommodation; crystalline lens; lens shape; zonular apparatus; zonule