Hashemi Hassan, Yekta Abbasali, Shokrollahzadeh Fereshteh, Aghamirsalim Mohammadreza, Ostadimoghaddam Hadi, Hashemi Alireza, Heydarian Samira, Khabazkhoob Mehdi
Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran.
Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
J Curr Ophthalmol. 2021 Mar 26;33(1):17-22. doi: 10.1016/j.joco.2019.06.004. eCollection 2021 Jan-Mar.
To determine the distribution of keratometry values in a wide age range of 6-90 years.
In this cross-sectional study, samples were selected from two villages in Iran using multi-stage random cluster sampling. After completing optometry and ophthalmic examinations for all cases, corneal imaging was done using Pentacam, and keratometry values were determined.
Of the 3851 selected people, 3314 people participated in the study, and after applying the exclusion criteria, analyses were done on data from 2672 people. Mean age of the participants was 36.30 ± 18.51 years (from 6 to 90 years). Mean keratometry (mean-K) in flat and steep meridians was 42.98 (42.9-43.06) diopters (D) and 43.98 (43.91-44.07) D, respectively. Average of mean-K was 43.48 (43.41-43.56) D. Mean-K increased linearly up to the age of 70 years, and the cornea became slightly flat afterwards (coefficient = 0.01; < 0.001). Mean-K was significantly higher in females ( < 0.001). Myopic cases had the highest mean-K ( < 0.001). The correlation of mean-K with age, gender, central corneal thickness, anterior chamber depth, pupil diameter, and spherical equivalent was investigated in a multiple regression model. Only older age and female gender showed a statistically significant association with mean-K. Overall, 31.62% (29.14-34.09) of the sample in this study had at least 1.0 D of corneal astigmatism.
This is one of the few studies worldwide that demonstrates changes in keratometry in a wide age range from childhood to old age. Results indicated that age and gender are variables associated with keratometry.
确定6至90岁广泛年龄范围内角膜曲率计测量值的分布情况。
在这项横断面研究中，采用多阶段随机整群抽样从伊朗的两个村庄选取样本。对所有病例完成验光和眼科检查后，使用Pentacam进行角膜成像，并确定角膜曲率计测量值。
在3851名被选中的人中，3314人参与了研究，应用排除标准后，对2672人的数据进行了分析。参与者的平均年龄为36.30±18.51岁（6至90岁）。平坦子午线和陡峭子午线的平均角膜曲率（平均K值）分别为42.98（42.9 - 43.06）屈光度（D）和43.98（43.91 - 44.07）D。平均K值的平均值为43.48（43.41 - 43.56）D。平均K值在70岁之前呈线性增加，之后角膜略有变平（系数 = 0.01；<0.001）。女性的平均K值显著更高（<0.001）。近视病例的平均K值最高（<0.001）。在多元回归模型中研究了平均K值与年龄、性别（此处英文gender后括号内容缺失）、中央角膜厚度、前房深度、瞳孔直径和等效球镜度的相关性。只有年龄较大和女性性别与平均K值显示出统计学上的显著关联。总体而言，本研究样本中有31.62%（29.14 - 34.09）至少有1.0 D的角膜散光。
这是世界上为数不多的几项研究之一，展示了从儿童到老年的广泛年龄范围内角膜曲率的变化。结果表明年龄和性别是与角膜曲率相关的变量。
