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Related Experiment Video

Updated: Jul 17, 2026

Sequential Application of Glass Coverslips to Assess the Compressive Stiffness of the Mouse Lens: Strain and Morphometric Analyses

Sequential Application of Glass Coverslips to Assess the Compressive Stiffness of the Mouse Lens: Strain and Morphometric Analyses

Published on: May 3, 2016

Stiffness gradient in the crystalline lens.

Henk A Weeber¹, Gabriele Eckert, Wolfgang Pechhold

¹AMO, Van Swietenlaan 5, 9728 NX Groningen, The Netherlands. henk.weeber@amo-inc.com

Graefe'S Archive for Clinical and Experimental Ophthalmology = Albrecht Von Graefes Archiv Fur Klinische Und Experimentelle Ophthalmologie

|February 8, 2007

Summary

The stiffness of the human crystalline lens increases with age, with significant variations between the center and periphery. This age-dependent stiffness gradient is crucial for understanding lens mechanics.

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Area of Science:

Ophthalmology
Biomechanical Engineering
Materials Science

Background:

Limited understanding of stiffness distribution within the human crystalline lens.
Overall lens stiffness has been previously studied, but regional variations remain underexplored.

Purpose of the Study:

To determine the stiffness gradient in the human crystalline lens.
To investigate the influence of age on the lens stiffness gradient.

Main Methods:

Measured local dynamic stiffness in 10 human crystalline lenses (19-78 years).
Utilized a small oscillating probe to assess local dynamic shear modulus (stiffness).
Measurements were performed in the equatorial cross-section of the lens.

Main Results:

Local dynamic shear modulus varied significantly with location in all lenses.
Central lens stiffness increased dramatically with age (up to 10^4 times higher in oldest vs. youngest).
Older lenses showed a stiffer center compared to the periphery, contrasting with findings in younger lenses.

Conclusions:

The dynamic stiffness of the crystalline lens exhibits a distinct gradient across its structure.
This stiffness gradient is demonstrably dependent on the age of the individual.
Both central and peripheral lens stiffness increase with age, but at different rates.