角膜塑形术对近视力及立体视觉的影响

Changes in near vision and stereopsis after orthokeratology

目的：观察近视患者配戴高透氧夜戴型硬性角膜塑形镜的近视力及裸眼近立体视觉的变化,分析其临床意义及变化规律,为正确评价角膜塑形术的临床疗效提供依据。 方法：随机选择眼科门诊接受角膜塑形术的青少年近视患者30例60眼,检测戴镜前及戴镜3 mo后裸眼近立体视觉及近视力,屈光不正按等效球镜分为3组：低度近视组（〈-3.00D）,中度近视组（-3.00～〈-6.00D）和高度近视组（≥-6.00D）,经统计学处理进行比较研究。 结果：戴角膜塑形镜3mo后与戴镜前比较：（1）远、近视力均提高,其差异具有极显著意义（P〈0.01）；低、中、高度近视组任意两组间近视力的差异无统计学意义（P〉0.05）；（2）裸眼近立体视锐度值降低,其差异具有极显著意义（P〈0.01）；低、中、高度近视组任意两组间裸眼近立体视觉的差异无统计学意义（P〉0.05）；裸眼近立体视与屈光参差显著相关（ Pearson系数r=0.778, P〈0.01）,且屈光参差越大,裸眼近立体视锐度越高；（3）角膜前表面平均K 值降低,其差异具有极显著意义（P〈0.01）；（4）中央角膜厚度、前房深度、眼压等参数的差异统计学上均无显著意义（P〉0.05）。 结论：角膜塑形镜能在短期内引起角膜前表面K值降低,从而改变角膜弯曲度,达到矫正近视的目的,提高远、近视力,同时对裸眼近立体视觉的提高有影响,角膜塑形术治疗前后患者的中央角膜厚度、前房深度、眼压等均无明显变化,提示角膜塑形术治疗安全有效。

AlM：To provide a proper assessment of the clinical use of orthokeratology by observing and analyzing the ocular biometric changes of the eyes and the stereopsis of the myopia. METHODS：Sixty eyes from 30 myopia （ from 8 to 17 years old） were fitted with orthokeratology. Stereopsis, visual acuity, near visual acuity, central corneal thickness, anterior chamber depth, average anterior corneal refractive power （ K value ） , and intraocular pressure were measured before the orthokeratology treatment and 3mo after it. Refraction was expressed as spherical equivalent （ SE） , and the subjects were divided into 3 groups according to refraction： low myopia group （SE〈-3.00D）, moderate myopia group （-3. 00D≤SE〈-6. 00D）, and high myopia group （SE≥-6. 00D）. RESULTS：All subjects had significant improvements in visual acuity and near visual acuity 3mo after the orthokeratology treatment （P〈0. 01）. ln the comparisons of any pair of the groups, there was no significant difference in the near visual acuity （ P〉0. 05 ）. Three months after the orthokeratology treatment, Naked eye near stereoacuity values of all subjects were decreased （P〈0. 01）. There was no significant difference in the comparisons of the differences of stereopsis between any pair of the groups （ P〉 0. 05 ）. There was significant correlation in stereopsis and anisometropia （ Pearson＆amp;nbsp;coefficient r = 0. 778, P 〈 0. 01 ）. And with greater anisometropia, the stereopsis was higher. All subjects had significantly lower K values than before 3mo after the orthokeratology treatment （ P〈 0. 01 ）. There was no significant difference in central corneal thickness, anterior chamber depth, and intraocular pressure （P〉0. 05）. CONCLUSlON：Orthokeratology could lower K value in a short time and change the corneal curvature to correct myopia, to improve visual acuity and near visual acuity. lt also has an influence on improving stereopsis. There are no obviously changes in patients＇ central corneal thickness, anterior chamber depth or intraocular pressure after the orthokeratology treatment, making it a safe and effective treatment for adolescent.