Measurement of Iris Thickness at Different Regions in Healthy Chinese Adults.

Qingchen Li,Huiming Wen,Jian Yu,Changbo Zhou,Yuan Zong,Chunhui Jiang,Xinghuai Sun,Guangxing Liu,Michele Figus

doi:10.1155/2021/2653564

Abstract

Purpose To study the variation of iris thicknesses in different regions and explore the possible correlations with age and gender. Methods Healthy Chinese adults were recruited; the anterior segment of their eyes was imaged by swept-source optical coherence tomography (SS-OCT). The horizontal scan of the right eye was selected, and the thicknesses of both the nasal and temporal irises were measured at 199 evenly spaced points. Results A total of 233 subjects with an average age of 36.79 ± 10.04 years (range 19 to 62) were included in the final analysis. The mean iris thicknesses of the temporal and nasal sides were 364.79 ± 47.58 μm and 372.44 ± 43.75 μm, respectively. The mean nasal iris thickness was positively correlated with age (β = 0.9 μm/year; P = 0.002), but the temporal one was not (β = 0.077 μm/year; P = 0.806). At 139 points of the nasal iris and 146 points of the temporal iris, the iris thickness was significantly correlated with age (P < 0.05). The thicknesses of the peripheral and pupillary parts were positively correlated with age, while the middle part was negatively correlated with age. No significant difference was observed in the mean iris thickness between genders (temporal: t = 1.597, P = 0.112; nasal: t = 1.870, P = 0.063), but females had a thicker iris than males at 50 points in the temporal side and 49 points in the nasal side (P < 0.05); no point in males was observed to have thicker iris compared to females. Conclusion Using SS-OCT and the novel method, thicknesses of the iris at different regions were measured. The thicknesses of the peripheral and pupillary irises increase with age, while the thicknesses of the middle part decrease.

Highlights

Aging is a natural process affecting almost all parts of the human body, including the eye
It is interesting to have a more complete understanding of how the iris thickness changes with aging. us, we developed a new method that was able to measure the thickness of the object at 199 evenly spaced points; formerly, using this method, we studied the anterior chamber depth (ACD) at different regions of the anterior chamber
Univariate linear regression analysis found that the mean nasal iris thickness was positively correlated with age (β 0.9 μm/year; P 0.002), but the temporal iris one was not (P 0.806)

Summary

Introduction

Aging is a natural process affecting almost all parts of the human body, including the eye. Studies had reported that the morphology of many important structures of the eye changes with aging. E relationship between iris thickness and age remains controversial. One could see that different parts of the iris have been studied; this controversy could imply that the iris thickness at different points might change differently. It is interesting to have a more complete understanding of how the iris thickness changes with aging. Us, we developed a new method that was able to measure the thickness of the object at 199 evenly spaced points; formerly, using this method, we studied the anterior chamber depth (ACD) at different regions of the anterior chamber. The iris thicknesses from 199 spaced points were measured and their potential correlation with age and gender was further explored

Methods

Results

Conclusion