关键词: 高原地区, 筛查性近视, 散光, 患病率, 眼轴轴长/角膜曲率半径比

Abstract: Objective To analyze the relationship between refractive status and refractive parameters of students in grades three-six in plateau area．Methods In September,2023,a random sampling method was used to select 535 students from grades three-six of two primary schools in Bomi County,Nyingchi City,for school screening．Distance uncorrected visual acuity（UCVA）,astigmatism and its axis position,equivalent spherical（SE）,axial length（AL）,corneal radius（CR）,and axial length/corneal radius ratio（AL/CR）were calculated and recorded．The data was analyzed using the statistical software SPSS 22.00. Results The general trend of AL and AL/CR for grade three-six students was increased with grade increasing,while SE decreased with grade increasing．The overall prevalence of screening myopia was 29.91%,and the prevalence of screening myopia in grades three to six was 20.35%,25.53%,30.53% and 51.38%,respectively．The overall prevalence rate of astigmatism was 51.59%,including 90.22%,7.61% and 2.17% for astigmatism with the rule,astigmatism against the rule and oblique astigmatism,respectively．About 40.37% of the students had poor vision．Screening myopia was diagnosed using non-cycloplegic optometry with SE ≤-0.50 D combined with UCVA<5.0．The sensitivity and specificity of AL/CR for screening myopia were 0.656 and 0.887,respectively,with a Youden index of 0.534 and an area under the curve（AUC）of 0.802．This was superior to the AL evaluation,which had an AUC of 0.764．Conclusions The prevalence of screening myopia increased rapidly with the increase of grade in grade 3 to 6 in plateau area．And there were high prevalence of astigmatism and more poor vision．AL/CR value has a certain clinical significance in the monitoring of screening myopia．

Key words: Plateau area, screening myopia, astigmatism, prevalence, axial length/corneal radius ratio