Gradient moduli lens models: How material properties and application of forces can affect deformation and distributions of stress

Kehao Wang, Demetrios Venetsanos, Jian Wang, Barbara K. Pierscionek

Research output: Contribution to journalArticle

5 Citations (Scopus)
13 Downloads (Pure)

Abstract

The human lens provides one-third of the ocular focussing power and is responsible for altering focus over a range of distances. This ability, termed accommodation, defines the process by which the lens alters shape to increase or decrease ocular refractive power; this is mediated by the ciliary muscle through the zonule. This ability decreases with age such that around the sixth decade of life it is lost rendering the eye unable to focus on near objects. There are two opponent theories that provide an explanation for the mechanism of accommodation; definitive support for either of these requires investigation. This work aims to elucidate how material properties can affect accommodation using Finite Element models based on interferometric measurements of refractive index. Gradients of moduli are created in three models from representative lenses, aged 16, 35 and 48 years. Different forms of zonular attachments are studied to determine which may most closely mimic the physiological form by comparing stress and displacement fields with simulated shape changes to accommodation in living lenses. The results indicate that for models to mimic accommodation in living eyes, the anterior and posterior parts of the zonule need independent force directions. Choice of material properties affects which theory of accommodation is supported.

Original languageEnglish
Article number31171
JournalScientific Reports
Volume6
DOIs
Publication statusPublished - 10 Aug 2016
Externally publishedYes

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Lenses
Materials properties
Muscle
Refractive index

Bibliographical note

This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

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Gradient moduli lens models : How material properties and application of forces can affect deformation and distributions of stress. / Wang, Kehao; Venetsanos, Demetrios; Wang, Jian; Pierscionek, Barbara K.

In: Scientific Reports, Vol. 6, 31171, 10.08.2016.

Research output: Contribution to journalArticle

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