透气性硬性接触镜矫正圆锥角膜的视觉质量评价

目的评价透气性硬性接触镜(RGPCL)和框架眼镜矫正圆锥角膜的视觉质量差异。方法对27例(54只眼)轻、中、重度圆锥角膜患者利用计算机辅助的角膜地形图,主观式波阵面像差仪和对比敏感度仪观察框架眼镜和RGPCL矫正时的角膜形态和视觉质量变化。结果轻度圆锥角膜30只眼,中度圆锥角膜13只眼,重度圆锥角膜11只眼,总体平均近视度和散光度分别为(6.92±3.66)和(5.75±1.85)D。66.6%的患眼裸眼视力≤0.15,96.3%的患眼裸眼视力≤0.3。矫正视力≥0.6者,戴用框架眼镜者为59.3%,戴用RGPCL者为100.0%;矫正视力≥1.0者,戴用框架眼镜者为20.4%,戴用RGPCL者为66.7%。配戴RGPCL后角膜地形图显示,角膜散光基本消除(<0.75D),表面形态显著球面化和规则化。圆锥角膜随病变程度加深,总体波阵面像差和各阶像差均显著增加。戴RGPCL的波阵面像差比裸眼明显降低,各阶RMS差异均有统计学意义(P<0.01),总体RMS从3.63μm降至1.39μm,2阶RMS从2.64μm降至0.81μm,去除2阶的总高阶RMS从2.35μm降至1.10μm,3阶RMS从1.78μm降至0.68μm,最为显著。对比敏感度及眩光对比敏感度曲线在全频段特别是中、高频段RGPCL比框架眼镜有显著升高。结论角膜前突变形引起的角膜不规则散光是圆锥角膜视觉功能低下,像差增大的主要原因,框架眼镜往往无法矫正,配戴适宜的RGPCL通过与泪液镜的有效弥合重塑成新的圆滑的中心光学界面,因而可有效消除角膜散光,减少像差,提高视力和对比敏感度曲线,明显改善视觉质量,使患者迅速回归正常学习与生活。

The evaluation of visual quality in keratoconus eyes corrected by rigid gas-permeable contact lens

OBJECTIVE: To evaluate the visual quality in keratoconus eyes corrected by rigid gas-permeable contact lens (RGPCL) and spectacles. METHODS: Corrected visual acuity, corneal topography, wavefront aberration and contrast sensitivity were measured in 27 keratoconus patients (54 eyes) before and after the fitting of RGPCL. RESULTS: The inclusive keratoconus eyes were diveded mild 30 eyes, moderate 13 eyes and sever 11 eyes. The average myopia and average astigmatism were (6.92 +/- 3.66) D and (5.75 +/- 1.85) D respectively. Uncorrected visual acuity (VA) in 96.3% keratoconus eyes was or= 0.6, while 100% by RGPCL. The VA in 20.4% of eyes corrected by spectacles were >or= 1.0, while 66.7% by RGPCL. Corneal topography study showed corneal toricity decreased to