角膜塑形镜配戴后眼正相对调节力增强的临床观察

Positive relative accommodation increase produced in response to overnight orthokeratology

目的观察青少年近视眼配戴角膜塑形镜后眼调节力的变化，探讨角膜塑形镜控制近视进展的机制。方法回顾性研究。对2006年7月至2008年7月及2014年7月至2016年7月在中国医科大学附属一院眼科门诊就诊的青少年近视组110例，正视眼组43例，青少年近视角膜塑形镜配戴组48例，应用综合验光仪检测调节幅度、正负相对调节力和隐斜度。对配戴组与同年龄段未配戴组正负相对调节进行比较，并对配戴组中19例验配前、后的相对调节力进行统计学分析。结果角膜塑形镜组配戴3个月后正相对调节力PRA（-4.32±1.59）D，明显高于同年龄段未配戴组PRA（-2.27±1.19）D，两组比较差异有统计学意义（P〈0.05）。而两组负相对调节力（NRA）比较差异无统计学意义（P〉0.05）。配戴组中19例验配前正相对调节力PRA（-2.49±1.05）D，配戴后PRA（-4.22±1.67）D，正相对调节力比配前明显增强，差异有统计学意义（P〈0.05）。结论该研究结果显示青少年近视眼配戴角膜塑形镜后眼正相对调节力增强，即调节储备增强，正相对调节力增强是角膜塑形镜延缓近视进展的重要机制之一。

Objective To observe the changes of accommodation with myopia adolescents after wearing orthokeratology, and to investigate the mechanism of orthokeratology controlling myopia progression. Methods A total of 110 adolescents with myopia, 43 adolescents were emmetropia, 48 patients wore orthokeratology. Phoria at distance and near, positive relative accommodation and negative relative accommodation （PRA/NRA） were measured with phoropter, and compared with the patients wearing frame glasses. The PRA and NRA before and after wearing orthokeratology in 19 patients were compared. Results The PRA after 3 months wearing orthokeratology group （-4.32±1.59） D were much higher than the patients wearing frame glasses （-2.27±1.19）D. There was significant difference in PRA （P〈0.05）. There was no significant difference in NRA. The PRA after wearing orthokeratology （-4.22＋1.67）D were higher than the PRA before wearing orthokeratology （-2.49±1.05）D, there was significant difference （P 〈0.05）. Conclusions The PRA is increased after wearing orthokeratology, the accommodation is increased, and it may be the reasonable mechanism of orthokeratology controlling myopia progression.