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Graefe's Archive for Clinical and Experimental Ophthalmology
Published in: Graefe's Archive for Clinical and Experimental Ophthalmology 4/2016

01-04-2016 | Refractive Surgery

Finite element modelling of radial lentotomy cuts to improve the accommodation performance of the human lens

Authors: H. J. Burd, G. S. Wilde

Published in: Graefe's Archive for Clinical and Experimental Ophthalmology | Issue 4/2016

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Abstract

Purpose

The use of a femtosecond laser to form planes of cavitation bubbles within the ocular lens has been proposed as a potential treatment for presbyopia. The intended purpose of these planes of cavitation bubbles (referred to in this paper as ‘cutting planes’) is to increase the compliance of the lens, with a consequential increase in the amplitude of accommodation. The current paper describes a computational modelling study, based on three-dimensional finite element analysis, to investigate the relationship between the geometric arrangement of the cutting planes and the resulting improvement in lens accommodation performance. The study is limited to radial cutting planes.

Methods

The effectiveness of a variety of cutting plane geometries was investigated by means of modelling studies conducted on a 45-year human lens.

Results

The results obtained from the analyses depend on the particular modelling procedures that are employed. When the lens substance is modelled as an incompressible material, radial cutting planes are found to be ineffective. However, when a poroelastic model is employed for the lens substance, radial cuts are shown to cause an increase in the computed accommodation performance of the lens. In this case, radial cuts made in the peripheral regions of the lens have a relatively small influence on the accommodation performance of the lens; the lentotomy process is seen to be more effective when cuts are made near to the polar axis.

Conclusions

When the lens substance is modelled as a poroelastic material, the computational results suggest that useful improvements in lens accommodation performance can be achieved, provided that the radial cuts are extended to the polar axis. Radial cuts are ineffective when the lens substance is modelled as an incompressible material. Significant challenges remain in developing a safe and effective surgical procedure based on this lentotomy technique.
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Metadata
Title
Finite element modelling of radial lentotomy cuts to improve the accommodation performance of the human lens
Authors
H. J. Burd
G. S. Wilde
Publication date
01-04-2016
Publisher
Springer Berlin Heidelberg
Published in
Graefe's Archive for Clinical and Experimental Ophthalmology / Issue 4/2016
Print ISSN: 0721-832X
Electronic ISSN: 1435-702X
DOI
https://doi.org/10.1007/s00417-016-3296-z

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