Surface change of the mammalian lens during accommodation.

@article{Zamudio2008SurfaceCO,
  title={Surface change of the mammalian lens during accommodation.},
  author={Aldo C. Zamudio and Oscar A. Candia and Chi-wing Kong and Brian Wu and Rosana Gerometta},
  journal={American journal of physiology. Cell physiology},
  year={2008},
  volume={294 6},
  pages={
          C1430-5
        }
}
Classical theories suggest that the surface area of the crystalline lens changes during accommodation while the lens volume remains constant. Our recent work challenged this view by showing that the lens volume decreases as the lens flattens during unaccommodation. In this paper we investigate 1) the magnitude of changes in the surface of the in vitro isolated cow lens during simulated accommodation, as well as that of human lens models, determined from lateral photographs and the application… 

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Surface and volume changes in the lens during accommodation.
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  • Medicine, Physics
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TLDR
I was excited by the results presented in the excellent paper by Sheppard et al. and very gratified that they acknowledged that the authors had predicted similar changes in human lens volume and surface based on mathematical modeling of human lens dimensions, using the Pappus theorem as well as experimentally induced changes in lens dimensions of isolated cow lenses under conditions mimicking accommodation.
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TLDR
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TLDR
A novel system that fluid movement can be measured across the polar and equatorial surface areas of isolated cow lenses supports that a fluid circulation consistent with the 1997 model is physiologically active.
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TLDR
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Three-dimensional magnetic resonance imaging of the phakic crystalline lens during accommodation.
TLDR
The results indicate that the capsular bag undergoes elastic deformation during accommodation, causing reduced surface area, and the observed volumetric changes oppose the theory that the lens is incompressible.
Pharmacological and physiological manipulation of ocular accommodation
TLDR
The studies presented herein suggest a forward movement of ciliary muscle mass is necessary for accommodation, and further research is required to establish whether a mechanical restriction occurs to the muscle with increasing age, resulting in presbyopia.
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  • Medicine
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PURPOSE The results of a recent study on accommodation in humans and baboons has revealed that lens fiber structure and organization are key components of the mechanism of accommodation. Dynamic…
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TLDR
This work summarized what is known about the anatomy and aging of the accommodative apparatus and how such changes might contribute to the loss of accommodative amplitude and proposed mechanism of accommodation different from that which is classically accepted.
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TLDR
It is concluded that PAs, which resemble geodesic domes, do not take an active part in near-point accommodation; but like SFs, may serve to resist overextension by internal pressure of the fiber mass or by zonular tension.
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