Zhang Z, Liu Y, Yang W, Lin Z, Li H, Li S
Zhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences, Gaungzhou, China.
Yan Ke Xue Bao. 1994 Sep;10(3):133-7.
We studied the corneal curvature of 161 eyes in 101 patients, aged from 50 to 80 years (mean: 63 years), with senile cataract using the Topographic Modeling System (TMS) preoperatively. The results revealed that mean surface asymmetry index (SAI) was 0.36 and mean surface regularity index (SRI) 0.79. Simulated keratometry reading (Sim K) was 44.46 D, and 43.56 D. Minimum K reading was 42.60 D. The same patterns of corneal topography in both eyes were 50% in 60 patients who had binocular examination. Astigmatism less than 1 D was 23% in 161 corneas. Corneal patterns included round (21.2%), oval 16.1%), symmetric and asymmetric bow-tie (22.2%), and irregular (40.4%). SRI and SAI of the irregular pattern were statistically higher than those of the round, oval and bow-tie patterns in our patients (P < 0.01 and P < 0.05). The results of our study determined that the cornea of eye with senile cataract preoperatively is not a perfect spherocylinder. It is asymmetrically aspheric, with less curvature peripherally than centrally.
我们使用地形建模系统（TMS）对101例年龄在50至80岁（平均63岁）的老年性白内障患者的161只眼睛进行了术前角膜曲率研究。结果显示，平均表面不对称指数（SAI）为0.36，平均表面规则性指数（SRI）为0.79。模拟角膜曲率读数（Sim K）分别为44.46 D和43.56 D。最小K读数为42.60 D。在进行双眼检查的60例患者中，双眼角膜地形图模式相同的占50%。在161只角膜中，散光小于1 D的占23%。角膜模式包括圆形（21.2%）、椭圆形（16.1%）、对称和不对称领结形（22.2%）以及不规则形（40.4%）。在我们的患者中，不规则模式的SRI和SAI在统计学上高于圆形、椭圆形和领结形模式（P < 0.01和P < 0.05）。我们的研究结果表明，老年性白内障患者术前眼睛的角膜并非完美的球柱面。它是不对称非球面的，周边曲率小于中央曲率。
