Changes in Lens Thickness and Amplitude of Accommodation with Age

Abstract

Introduction: The human crystalline lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina and, by changing shape, it adjusts focal distance and this function of the lens is called accommodation. Accommodation is the way, the eye increases optical power as it is necessary to produce a clear image of an object when it draws near the eye. Ageing reduces the ability of the lens to change shape, to adjust for close or distance vision. Aim: To study the changes of lens thickness and Amplitude of Accommodation (AA) with age. Materials and Methods: In this cross-sectional study, 40 healthy females were recruited from September to December 2018. The right eyes of 40 healthy participants were divided into two groups, the group 1 of 20 younger subjects (age range 18 to 28 years, mean age 21.9±2.73 years), and group 2 of middleaged 20 subjects (age range 40 to 50 years, mean age 44.6±3.95 years). The lens thickness and AA was measured using A-scan ultrasonography and push-up method respectively. Statistical analysis was performed using SPSS, version 15 (SPSS Inc, Chicago, Illinois). Results: The AA using push-up method in group 1 (11.28±1.44 D) was significantly higher than the AA in group 2 (4.49±1.01 D) and the mean difference was found 6.79 D. Unpaired t-test found p0.05 considered was non-significant. Conclusion: The lens thickness increases with age but this increase was found statistically non-significant. The AA significantly decreased with increasing age.

Keywords

• a-scan ultrasonography
• crystalline lens thickness
• push-up method