近视性屈光参差者双眼调节反应的研究

Analyze of the accommodative response in myopia anisometropes

目的研究在辐辏闭环情况下，近视性屈光参差者的调节滞后、调节反应／调节刺激曲线线性部分的斜率等眼动参数与正视者调节参数之间的差异的关系。方法病例对照研究。40名志愿者（年龄18岁至31岁），其中正视者20人（等效球镜度＋0．37至-0．25D），20例近视性屈光参差者（双眼球镜度数差〉2．50D且〈7．00D，散光度数〈1．00D）。在辐辏闭环状态下用WV-500双目自动验光仪测量1．00、2．00、3．00、4．00D各调节刺激下的调节反应并得出AR／AS曲线及其线性部分的斜率。对正视组和屈光参差组的高低度数眼的客观调节滞后量、调节反应／调节刺激斜率、主观调节滞后量进行独立样本t检验。结果在闭环条件下，屈光参差者高度数眼调节滞后量最大，其次是低度数眼、正视眼。在3．00和4．00D刺激水平，屈光参差组高度数眼与正视眼调节滞后量之间差异有统计学意义（t=2．055，2．410；P〈0．05）。屈光参差者两眼之间AR／AS斜率差异无统计学意义（P〉0．05），但屈光参差高度数眼的斜率低于正视眼的AR／AS斜率（t=2．550，P〈0．05）。结论屈光参差者两眼调节反应不等，高度眼表现出更多的调节滞后。屈光参差者双眼在等量调节刺激下，表现为不等量的调节反应，高度数眼要产生相同的调节反应，需要更多的调节刺激。可能与调节中枢的控制增益不同有关，也可能与“睫状肌-晶状体”系统调节反应阈值较高有关。

Objectives This study is designed to analyze the accommodative hysteresis, accommodative responses between two eyes of anisometropes. The difference of the shape and slope of the accommodative response curves under closed-loop state is evaluated. A comparison study between emmetropes and anisometropes was assessed as well. Methods It was a case-control study. Forty volunteers, （age from 20 to 31 years ）participated in the research. 20 subjects had emmetropia（ spherical equivalent ＋ 0. 37D to -0. 25D in both eyes）, 20 subjects had anisometropia with spherical power difference ranging from 2. 50D to 7. 00D between their two eyes. Accommodation taken by objective methods： RE and accommodative response （AR） to 1.00D, 2.00D, 3.00D, 4.00D stimulus were measured objectively by WV-500 binocular infrared optometer （Grand Seiko Co. Japan）. The slope of the AR/AS was calculated and compared between different groups. Results Under closed-loop state, the higher refractive error eye of anisometropia had most accommodation lag followed by lower eye and emmetropic eye. In stimulus of 3. 00D and 4. 00D, the differences between higher eye and emmetropic eye were significant （ t = 2. 055,2. 410 ; P 〈 0.05 ） . The differences of the slopes between two eyes of ainisometropes under all conditions were without significant difference （ P 〉 0. 05 ）. But the slopes of higher refractive error were lower than that of emmetropoes （ t = 2. 550, P 〈 O. 05 ） . Conclusions The accommodative responses of two eyes of anisometropia are different, the higher eye of anisometropia shows higher accommodation lag. Every non accommodation balance phenomenon showed by anisometropia may be associated either with different accommodation controller gain, or with higher threshold of ＂cilliary-lens＂ system or both. It is needed further study to clarify.