McCarey B E, Amos C F, Taub L R
Department of Ophthalmology, Emory University School of Medicine, Atlanta, GA 30322.
CLAO J. 1993 Apr;19(2):114-20.
We compared the surface topography of 38 soft contact lenses in situ to the corneal topography of 17 patients. The analyzed lenses consisted of patients' spherical and toric lenses as well as additional spherical lenses of various thicknesses. Thirteen brands of contact lenses were worn; corneal astigmatism ranged from 0.12 to 3.81 D. Our hypothesis was that toric soft contact lens neutralization of corneal surface astigmatism occurred through the creation of a more spherical anterior surface. Videokeratoscopy was used to analyze corneal surface changes with contact lens wear. The correction of astigmatism for toric corneas (toricity > 0.75 D) fit with toric lenses (i.e., the difference between the surfaces of the cornea and anterior lens) showed surface astigmatism neutralization of only 34 +/- 38%. The greater the astigmatism, the greater the neutralization. Spherical lenses not only failed to mask corneal toricity, but actually increased it. The topographic map can be a valuable asset for analyzing and possibly improving contact lens fitting of toric contact lenses.
我们将38片软性隐形眼镜在原位的表面形貌与17名患者的角膜地形图进行了比较。所分析的镜片包括患者的球面和复曲面镜片以及不同厚度的额外球面镜片。佩戴了13个品牌的隐形眼镜；角膜散光范围为0.12至3.81 D。我们的假设是，复曲面软性隐形眼镜通过形成更球形的前表面来中和角膜表面散光。使用角膜地形图仪分析佩戴隐形眼镜时角膜表面的变化。对于复曲面角膜（散光度数>0.75 D）与复曲面镜片适配（即角膜和镜片前表面之间的差异），散光的矫正显示表面散光仅中和了34±38%。散光越大，中和效果越好。球面镜片不仅未能掩盖角膜散光，实际上还增加了散光。地形图对于分析并可能改善复曲面隐形眼镜的验配可能是一项有价值的工具。
