目的：对比观察角膜塑形镜联合低浓度阿托品治疗的儿童在停用低浓度阿托品前后的近视进展情况，判断角膜塑形镜配戴者的停药反弹效应并根据瞳孔直径变化分析其产生原因。

方法：前瞻性病例对照研究。纳入2022-01/06就诊于西安市第一医院应用角膜塑形镜并联合0.01%阿托品眼用凝胶控制近视儿童80例，1 a后根据是否停药分为停药组(A组，40例)和继续用药组(B组，40例)，观察A组儿童停药前后1 a内的眼轴(AL)和等效球镜度(SE)变化，分析停药前后的近视进展情况，并对比观察A组和B组儿童2 a内的AL、瞳孔直径(PD)和SE变化，并分析PD与AL增长量的关系。

结果：A组儿童在停药后0.5、1 a时AL分别增长0.17±0.23、0.29±0.18 mm，均大于停药前0.5、1 a(t=5.318、2.983，均P<0.001)，停药前后1 a时的SE增长量无差异(P>0.05)。联合用药时A组和B组在基线，随访0.5、1 a时的AL、PD变化均无差异(均P>0.05)，随访1.5 a时A组的AL增长量大于B组(0.32±0.27 mm vs 0.26±0.20 mm，t=7.363，P<0.001)，PD小于B组(3.60±1.25 mm vs 4.12±1.92 mm，t=-7.541，P<0.001)，随访2 a时A组的AL增长量大于B组(0.44±0.18 mm vs 0.32±0.14 mm，t=5.709，P<0.001)，PD小于B组(3.67±1.31 mm vs 4.02±1.67 mm，t=-4.281，P<0.001)。2 a内每0.5 a及每1 a随访时线性回归分析显示，PD和AL增长量呈负相关(R²=-0.156、-0.190，均P<0.001)。

结论：配戴角膜塑形镜的儿童停用低浓度阿托品后，AL较停药前增长较快，PD缩小而SE变化不大。较继续用药的情况相比，停止用药会导致AL进展较快而屈光度变化不大，且在配戴角膜塑形镜时瞳孔直径越大AL进展越慢。

METHODS:A prospective case-control study was conducted to collect 80 children with myopia who were treated with orthokeratology lenses combined with 0.01% atropine ophthalmic gel at the Xi'an No.1 Hospital from January to June 2022. One year later, they were divided into a drug withdrawal group(Group A, 40 cases)and a continuous medication group(Group B, 40 cases)based on whether they stopped taking the medication. The progression of myopia before and after drug withdrawal was observed by analyzing changes in axial length(AL)and spherical equivalent(SE)in the group A within 1 a before and after drug withdrawal. The changes in AL, pupil diameter(PD), and SE were compared between the group A and group B within 2 a, and the correlation between PD and AL growth was analyzed.

RESULTS:In the group A, the AL increased by 0.17±0.23 and 0.29±0.18 mm at 0.5 and 1 a after drug withdrawal, respectively, which were both greater than before drug withdrawal(t=5.318, 2.983, both P<0.001). There was no statistically significant difference in SE growth between the two time points(P>0.05). There were no statistically significant differences in AL and PD between the group A and group B at baseline, 0.5 and 1 a during combined medication(all P>0.05). At 1.5 a, the AL growth of the group A was greater than that of the group B(0.32±0.27 mm vs 0.26±0.20 mm, t=7.363, P<0.001), and the PD was smaller than that of the group B(3.60±1.25 mm vs 4.12±1.92 mm, t=-7.541, P<0.001). At 2 a, the AL growth of the group A was greater than that of the group B(0.44±0.18 mm vs 0.32±0.14 mm, t=5.709, P<0.001), and the PD was smaller than that of the group B(3.67±1.31 mm vs 4.02±1.67 mm, t=-4.281, P<0.001). Correlation analysis showed a negative correlation between PD and AL growth at 0.5 and 1 a follow-ups over 2 a(R²=-0.156, -0.190, both P<0.001).

CONCLUSION: After stopping low-concentration atropine in children wearing orthokeratology lenses, AL increased more rapidly than before drug withdrawal, PD decreased, and SE changed little. Compared with continuous medication, discontinuation of medication led to faster progression of AL with little change in diopter, and the larger the PD during orthokeratology lens wear, the slower the progression of AL.