Age-Related Changes to the Three-Dimensional Full Shape of the Isolated Human Crystalline Lens.

PURPOSE

Studying the full shape crystalline lens geometry is important to understand the changes undergone by the crystalline lens leading to presbyopia, cataract, or failure of emmetropization, and to aid in the design and selection of intraocular lenses and new strategies for correction. We used custom-developed three-dimensional (3-D) quantitative optical coherence tomography (OCT) to study age-related changes in the full shape of the isolated human crystalline lens.

METHODS

A total of 103 ex vivo human isolated lenses from 87 subjects (age range, 0-56 years) were imaged using a 3-D spectral-domain OCT system. Lens models, constructed after segmentation of the surfaces and distortion correction, were used to automatically quantify central geometric parameters (lens thickness, radii of curvatures, and asphericities of anterior and posterior surfaces) and full shape parameters (lens volume, surface area, diameter, and equatorial plane position). Age-dependencies of these parameters were studied.

RESULTS

Most of the measured parameters showed a biphasic behavior, statistically significantly increasing (radii of curvature, lens volume, surface area, diameter) or decreasing (asphericities, lens thickness) very fast in the first two decades of life, followed by a slow but significant increase after age 20 years (for all the parameters except for the posterior surface asphericity and the equatorial plane position, that remained constant).

CONCLUSIONS

Three-dimensional quantitative OCT allowed us to study the age-dependency of geometric parameters of the full isolated human crystalline lens. We found that most of the lens geometric parameters showed a biphasic behavior, changing rapidly before age 20 years and with a slower linear growth thereafter.