Department of Ophthalmology and Visual Science, Tokyo Medical and Dental University, Tokyo, Japan.
Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland.
Ophthalmic Res. 2022;65(1):1-3. doi: 10.1159/000521194. Epub 2021 Dec 2.
Uncorrected refractive error is one of the major causes of visual impairment in children and adolescents worldwide. During the COVID-19 epidemic, home isolation is considered a boost to the progression of children's myopia. Under geographical conditions of high altitude and strong sunshine, the Tibetan plateau is the main residence of the Tibetan population, where little information is available about the refractive status and developmental trajectory. Therefore, this article aimed to evaluate the distribution, progression, and associated factors of the refractive status in second-grade children in Lhasa after COVID-19 quarantine.
Students from 7 elementary schools completed comprehensive ocular examinations in the Lhasa Childhood Eye Study. Data regarding cycloplegic refraction and corneal biometry parameters, including axial length (AL), corneal power, anterior chamber depth (ACD), and other demographic factors, were analyzed.
A total of 1,819 students were included, with a mean age of 7.9 ± 0.5 years, of which 961 were boys (52.8%), and 95.1% were Tibetan. The prevalence of myopia, emmetropia, mild hyperopia, and hyperopia was 10.94%, 24.02%, 60.80%, and 4.24%, respectively. Besides, the average cycloplegic spherical equivalent refraction (SER) was +1.07 ± 0.92 diopter (D) before the COVID-19 quarantine and +0.59 ± 1.08D after the quarantine ( < 0.05), with a growth rate of 7%. Moreover, the prevalence of hyperopia in girls was significantly higher than that of boys ( < 0.001). Nonetheless, the proportion of myopia and emmetropia was similar ( = 0.75). Meanwhile, children in suburban schools had a significantly lower proportion of myopia ( < 0.001). The average AL, ACD, lens power (LP), and AL-to-corneal radius (AL/CR) ratio were 22.79 ± 0.78 mm, 3.54 ± 0.21 mm, 25.12 ± 1.48D, and 2.93 ± 0.08, respectively. The results of AL, ACD, and AL/CR for girls were significantly lower than for boys, while the result of LP is the opposite ( < 0.001). Finally, multivariate regression analysis revealed that SER was negatively correlated with AL, LP, and AL/CR ratio, while positively correlated with CR and ACD ( < 0.001).
This study found that after the COVID-19 confinement, myopia progressed faster in Lhasa children but was still significantly lower than that of plain cities in China. Compared to short-term confinement, this acceleration was more likely related to the growth and general trend of myopia in children. Collectively, these findings help to explore the differences in ocular growth and development among children of different ethnic groups.
未矫正的屈光不正(refractive error)是全球儿童和青少年视力损害的主要原因之一。在 COVID-19 疫情期间,居家隔离被认为是儿童近视进展的助推因素。在高海拔和强阳光的地理条件下,青藏高原是藏族人口的主要居住地,但关于该地区儿童屈光状态和发育轨迹的信息较少。因此,本文旨在评估 COVID-19 隔离后拉萨市二年级儿童的屈光状态分布、进展和相关因素。
来自 7 所小学的学生在拉萨儿童眼研究中完成了全面的眼部检查。分析了睫状肌麻痹验光和角膜生物测量参数,包括眼轴(axial length,AL)、角膜屈光力(corneal power)、前房深度(anterior chamber depth,ACD)和其他人口统计学因素的数据。
共纳入 1819 名学生,平均年龄为 7.9 ± 0.5 岁,其中 961 名为男生(52.8%),95.1%为藏族。近视、正视、轻度远视和远视的患病率分别为 10.94%、24.02%、60.80%和 4.24%。此外,COVID-19 隔离前平均睫状肌麻痹球镜等效屈光度(spherical equivalent refraction,SER)为+1.07 ± 0.92 屈光度(diopter,D),隔离后为+0.59 ± 1.08D(<0.05),增长率为 7%。此外,女孩的远视患病率明显高于男孩(<0.001)。然而,近视和正视的比例相似(=0.75)。同时,郊区学校的儿童近视比例显著较低(<0.001)。平均 AL、ACD、晶状体屈光力(lens power,LP)和 AL/角膜半径比(AL-to-corneal radius,AL/CR)分别为 22.79 ± 0.78mm、3.54 ± 0.21mm、25.12 ± 1.48D 和 2.93 ± 0.08。女生的 AL、ACD 和 AL/CR 结果明显低于男生,而 LP 结果则相反(<0.001)。最后,多元回归分析显示,SER 与 AL、LP 和 AL/CR 呈负相关,与 CR 和 ACD 呈正相关(<0.001)。
本研究发现,COVID-19 隔离后拉萨儿童的近视进展更快,但仍明显低于中国平原城市。与短期隔离相比,这种加速更可能与儿童近视的生长和总体趋势有关。总之,这些发现有助于探讨不同民族儿童眼生长发育的差异。