Secondary Logo

Journal Logo

Institutional members access full text with Ovid®

The Thickness of the Aging Human Lens Obtained from Corrected Scheimpflug Images

DUBBELMAN, MICHIEL, MSc; VAN DER HEIJDE, G. L., PhD; WEEBER, and HENK A., MSc

Optometry and Vision Science: June 2001 - Volume 78 - Issue 6 - p 411-416
ARTICLES
Buy

Commonly, measurements of lens thickness are performed using A-scan ultrasonography or slitlamp Scheimpflug photography. Both techniques have their drawbacks in the study of presbyopia: ultrasonography requires the velocity of sound in the lens which may change with age, whereas Scheimpflug photography requires knowing the refractive index of the lens to enable correction of the photographs for the distortion due to the refraction of the cornea and lens. By combining Scheimpflug photography and axial optical eye-length measurements, we were able to individually correct the Scheimpflug images for distortion and calculate the refractive index and thickness of the human lens. Lens thickness of 90 subjects ranging in age between 16 and 65 years was measured, and an average increase of 24 μm/year was found. This value is consistent with ultrasonographic measurements assuming an age-independent velocity of sound in the lens of 1641 m/s. The posterior lens surface recedes from the cornea with age, and this backward movement does not differ significantly from the forward movement of the anterior lens surface.

Department of Clinical Physics & Informatics, Vrije Universiteit, Amsterdam, The Netherlands (MD, GLV), Applied Research, Pharmacia, Groningen, The Netherlands (HAW)

G.L. van der Heijde

Department of Clinical Physics & Informatics

VU Medical Center

PO Box 7057

1007 MB Amsterdam

The Netherlands

email: gl.heijde@vumc.nl

© 2001 American Academy of Optometry