附加三棱镜对正视眼调节反应和调节微波动的影响

Influences of prisms on accommodative response and microfluctuation in emmetropias

背景有效控制青少年近视的进展是视光学研究领域的热点之一，有学者采用附加底朝内（BI）三棱镜的方法控制近视的进展，然而由于改变眼的集合会影响调节反应，因此这种方法的效果值得讨论。目的观察正视眼附加不同性质的三棱镜后调节反应和调节微波动的变化。方法采用前瞻性研究方法，纳入2014年7月在北京大学人民医院参加体检的正常受试者22人，年龄21-27岁，受试眼均无屈光不正。受试者分别自愿接受未附加三棱镜、附加3 BI和3 底朝外（BO）三棱镜的干预，各种干预过程间隔3min，测量间隔期间嘱患者眺望远处。采用开放视野红外自动验光仪分别在不同干预情况下记录瞳孔直径和调节反应曲线，采集的屈光度数据减去一3．0D即为调节反应，以调节反应的均方根（RMS）作为调节微波动幅度。采用一维离散傅里叶变换分析调节反应曲线的频谱特征。采用重复测量单因素方差分析对3种干预下调节反应值、调节微波动幅度和瞳孔直径的差异进行比较。结果未附加三棱镜、附加3“BI三棱镜和附加3‘BO三棱镜后受试眼的调节反应值分别为（＋O．31±0．78）、（＋O．5l±0．75）和（＋O．18±0．72）D，总体比较差异有统计学意义（F=28．078，P=0．000），其中与未附加三棱镜比较，附加3 BI三棱镜后受试眼调节滞后量增加，而附加3 BO三棱镜后受试眼调节滞后量下降，差异均有统计学意义（P=0．000、0．012）。未附加三棱镜、附加3 BI三棱镜和附加3 BO三棱镜后受试眼调节微波动幅度的差异比较无统计学意义（F=0．062，P=0．879）。未附加三棱镜、附加3 BI三棱镜和附加3 BO三棱镜受试眼调节反应频谱低频信号功率（0-0．5Hz）分别占总功率（0-2．5Hz）的97．5％、98．3％和91．4％。附加3 BI的三棱镜后受试者的平均瞳孔直径为（5．37±0．69）mm，大于未附加三棱镜受试者的（5．07±0．66）mm和附加3 BO三棱镜后的（5．01±0．69）mm，差异均有统计学意义（均P=0．000）。结论与附加BI三棱镜相比，附加BO三棱镜能够改善调节滞后，缩小瞳孔，同时减少调节反应中的低频信号成分。

Background How to control progression of myopia is a central issue in clinical optometry. Some clinical trials showed that wearing base-in （BI） prism can slow down progression of myopia to certain degree. However,whether BI prism or base-out （BO） prism should be used is worth discussing. Objective This study was to investigate the influences of different prisms on accommodative response and microfluctuation in emmetropias. Methods This clinical trail was approved by Ethic Committee of Peking University People＇s Hospital. During July in 2014,twenty-two emmetropias of 22 normal volunteers aged 21-27 years were recruited from Peking University People＇s Hospital under the written informed consent. An open-field infrared refractometer was used to monitor and record pupil diameter and accommodative response under three conditions including non-prism,3a BI prism,and 3 BO prism. The accommodative response value was calculated as the difference between reading value and - 3.0 D, and root mean square （RMS） of aecommodative response value served as amplitude of accommodative microfluctuation. Spectrum of accommodative response was analyzed by one dimension discrete Fourier transformation. The differences of accommodative response value, amplitude of accommodative microfluctuation and pupil diameter among three conditions were compared using repeated one-way ANOVA. Results The accommodative response values were （ ＋0. 31± 0.78 ） , （ ＋ 0.51 ± 0. 75 ） and （ ＋ 0. 18 ± 0. 72 ） D under the non-prism, 3 BI prism and 3a BO prism conditions, respectively,with a significant difference among them （ F = 28. 078, P = 0. 000 ） , and compared with the non-prism condition,the accommodative lag of 3 BI prism condition was increased and that of 3 BO prism condition was reduced （P = 0.000, 0.012 ）. No significant difference was found in the amplitude of accommodative microfluctuation among the three conditions （ F= 0. 062, P = 0. 879 ）. The percentages of low frequency signal power （0-0.5 Hz）/total power （0-2.5 Hz） was 97.5% ,98.3% and 91.4% under the non-prism,3 BI prism and 3 BO prism condition,respectively. The pupil diameter was （5.37 ±0.69） mm under the 3 BI prism condition, which was larger than （5.07±0. 66） mm under the non-prism condition and （5.01±0. 69） mm under the 3aBO prism condition （both at P = 0. 000）. Conclusions Compared with wearing 3 BI prism, wearing 3a BO prism lessens the accommodative lag, decreases the pupil diameter and reduces the power of low frequency component in accommodative response.