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Updated: Aug 2, 2026
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Sequential Application of Glass Coverslips to Assess the Compressive Stiffness of the Mouse Lens: Strain and Morphometric Analyses
Published on: May 3, 2016
Modelling the mechanics of accommodation and presbyopia
1University Laboratory of Physiology, University of Oxford, UK. sjj@physiol.ox.ac.uk
Summary
Finite element modeling reveals the human eye lens power decreases with ciliary body stretch, contradicting some theories. This study also highlights inconsistencies in current ocular modeling data.
Area of Science:
- Ophthalmology
- Biomechanical Engineering
- Computational Biology
Background:
- The relationship between ciliary body diameter changes and human ocular lens refractive power is debated.
- Previous models have not fully accounted for the non-linear geometric changes in the lens during accommodation.
Purpose of the Study:
- To compute the relationship between ciliary body diameter changes and ocular lens refractive power using finite element methods.
- To investigate the validity of existing mathematical models and published data for ocular biomechanics.
Main Methods:
- Finite element analysis was employed to model the human ocular lens.
- Literature data on material properties (Fisher, 1969) and initial geometry (Brown, 1973) were utilized.
- Non-linear geometric changes during accommodation were incorporated into the models.
Main Results:
- The models predict a decrease in lens power with ciliary body stretch, consistent with conventional understanding, not an increase as recently claimed.
- A decrease in the amplitude of accommodation was modeled between ages 29 and 45.
- Inconsistencies were found when applying Brown's (1973) data to an 11-year-old eye model, suggesting potential issues with data or assumptions.
Conclusions:
- The human ocular lens responds to ciliary body stretch with a decrease in refractive power.
- Current biomechanical models and supporting data require further validation and refinement.
- More research is needed to ensure the accuracy of assumptions regarding ocular geometry and material properties for reliable modeling.
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