The eye lens: age-related trends and individual variations in refractive index and shape parameters

Pierscionek, Barbara K. and Bahrami, Mehdi and Hoshino, Masato and Uesugi, Kentaro and Regini, Justyn and Yagi, Naoto (2015) The eye lens: age-related trends and individual variations in refractive index and shape parameters. Oncotarget, 6 (31). pp. 30532-30544. ISSN 1949-2553

[img]
Preview
Text
Published Version
Available under the following license: Creative Commons Attribution.

Download (6MB) | Preview
Official URL: https://doi.org/10.18632/oncotarget.5762

Abstract

The eye lens grows throughout life by cell accrual on its surface and can change shape to adjust the focussing power of the eye. Varying concentrations of proteins in successive cell layers create a refractive index gradient. The continued growth of the lens and age-related changes in proteins render it less able to alter shape with loss of capacity by the end of the sixth decade of life. Growth and protein ageing alter the refractive index but as accurate measurement of this parameter is difficult, the nature of such alterations remains uncertain. The most accurate method to date for measuring refractive index in intact lenses has been developed at the SPring-8 synchrotron. The technique, based on Talbot interferometry, has an X-ray source and was used to measure refractive index in sixty-six human lenses, aged from 16 to 91 years. Height and width were measured for forty-five lenses. Refractive index contours show decentration in some older lenses but individual variations mask age-related trends. Refractive index profiles along the optic axis have relatively flat central sections with distinct micro-fluctuations and a steep gradient in the cortex but do not exhibit an age-related trend. The refractive index profiles in the equatorial aspect show statistical significance with age, particularly for lenses below the age of sixty that had capacity to alter shape in vivo. The maximum refractive index in the lens centre decreases slightly with age with considerable scatter in the data and there are age-related variations in sagittal thickness and equatorial height.

Item Type: Journal Article
Keywords: ageing, eye lens, refractive index gradients, growth, size, Gerotarget
Faculty: ARCHIVED Faculty of Health, Social Care & Education (until September 2018)
Depositing User: Lisa Blanshard
Date Deposited: 22 Feb 2021 12:53
Last Modified: 09 Sep 2021 19:01
URI: https://arro.anglia.ac.uk/id/eprint/706347

Actions (login required)

Edit Item Edit Item