Original Article
Research of Corneal Power Distribution and Age-Related Change in Cornea
Zhongye Wang, Xiuhua Liu, Min Zhang, Mingming Liu, Yaqin Jiang
Published 2023-01-25
Cite as Chin J Optom Ophthalmol Vis Sci, 2023, 25(1): 44-49. DOI: 10.3760/cma.j.cn115909-20210930-00403
Abstract
Objective:To investigate the distribution characteristics of corneal power of 2 mm, 4 mm and 6 mm diameter zones centered on the pupil and age-related change in cornea.
Methods:In this retrospective serial case study, a total of 254 eyes were included by randomly, which were divided into three groups by age, including 20-39 age group (Group A, 102 eyes), 40-59 age group (Group B, 73 eyes) and ≥60 age group (Group C, 79 eyes). Simulated keratometry (Simk), total corneal refractive power (TCRP) were evaluated. Analysis of Variance was used for comparing the difference between Simk and TCRP. Evaluating uniformity of Simk and TCRP was based on Bland-Altman plot. Regression analysis was used for the age-related trend of Simk and TCRP. Paired-samples t test was used to compare the difference between Simk and TCRP in 2, 4 and 6 mm.
Results:The Simk and TCRP of 2, 4 mm diameter zones centered on the pupil were significant differences between them (t=6.30, P=0.002; t=4.44, P=0.001); However, The Simk and TCRP of 6 mm diameter zones centered on the pupil were no statistically significant differences between them (P>0.05). In 2 mm diameter zones centered on the pupil, there were statistically significant differences between three groups (F=4.66, P=0.010; F=3.87, P=0.022), Among them, group A was significant different from B and C (P<0.05). In 4 mm diameter zones centered on the pupil,there were statistically significant differences between three groups (F=6.85, P=0.001; F=6.07, P=0.003). Among them, group A was significant different from B and C (P<0.05). In 6 mm diameter zones centered on the pupil, there were statistically significant differences between three groups (F=9.91, P<0.001; F=10.15, P<0.001), both Simk and TCRP of A group in all corneal diameter zones showed statistically significant differences with B, C group respectively (P<0.001).
Conclusion:Simk and TCRP centered on pupil and the age-related change in corneal should be taken seriously in corneal refractive surgery and cataract surgery. Simk and TCRP shows steeper with aging, which may tend to be stable after 40 years old.
Key words:
region; age; simulated keratometry; total corneal refractive power
Contributor Information
Zhongye Wang
Department of Ophthalmology, Hekou People's Hospital, Dongying 257200, China
Xiuhua Liu
Wei Fang Eye Hospital, Weifang 261000, China
Min Zhang
Wei Fang Eye Hospital, Weifang 261000, China
Mingming Liu
Wei Fang Eye Hospital, Weifang 261000, China
Yaqin Jiang
Wei Fang Eye Hospital, Weifang 261000, China
