Age-related changes in optical density and geometry of human crystalline lens measured with SS-OCT.

Abstract

Purpose : To demonstrate in vivo three-dimensional imaging of crystalline lens in healthy eyes with SS-OCT. To objectively determine age-related effects on the crystalline lens by studying lens geometry and optical densities of back-scattered signals from sub-layers of the lens.

Methods : This study includes 50 eyes of 50 healthy volunteers (age range: 9-78 years old). Volumetric images of the crystalline lens were acquired for each eye using the SS-OCT system and the optical scatter index was measured using a double-pass system. The radius of curvature (ROC) and thickness of sub-layers of the lens was measured after refraction correction of the segmented layers. The enhanced intensity image is used to measure densitogram with the optical axis as the center of the image and to average the intensity values in the 54 μm region of interest (ROI). The Oxford nomenclature was used as a reference for the segmentation of distinct CL zones and the nucleus (figure 1). The enhanced intensity image is also used to determine the mean scattering index intensity of each layer of the crystalline lens.

Results : The thickness of the whole lens and measured thickness of the cortex increases with age. The mean ROC of the anterior cornea is 7.34 ± 0.24 mm, the posterior cornea is 6.39 ± 0.20 mm, the anterior lens is 10.1 ± 1.7 mm, the anterior nucleus is 4.06 ± 0.37 mm, the posterior nucleus is 3.67 ± 0.33 mm, the posterior lens is 5.90 ± 0.40 mm. ROC of anterior lens interface, anterior nucleus, and posterior nucleus decreases with age. However, there was no statistical correlation of age with ROC measured for the posterior lens (R = 0.15, P = 0.298). Thickness and mean intensity signal of each layer of the crystalline lens and their relationship with the aging of the eyes are presented in figure 2.

Conclusions : The SS-OCT imaging analysis of the lens indicated age-dependent development of sub-layers in the crystalline lens. SS-OCT for lens imaging is a useful tool for performing in vivo fundamental studies on the development and aging of the human lens.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.

 

Scheme of densitogram creation. (A) 3-D OCT dataset of a 41 years-old subject. (B) Schematic diagram of the human lens showing different layers together with the ROI in the central area. (C) Resulting densitogram revealing different layers of CL.

 

Comparing age with (A) Radii of curvature, (B) thickness, and (C) mean intensity of the crystalline lens and its sub-layers.