近视眼与正常眼的角膜地形图差异

为了解中轻度近视眼的发病机理，应用计算机辅助的角膜镜摄影法观察３５只轻、中度近视眼的角膜，并与３５只正常眼比较。结果显示，近视眼角膜表面规划指数（ｓｕｒｆａｃｅ ｒｅｇｕｌａｒｉｔｙ ｉｎｄｅｘ，ＳＲＩ值、角膜中心屈光度、Ｓｉｍｋ及以角膜为中心，直径为３、５７ｍｍ的平均角膜屈光度较正常眼高（Ｐ〈０．０５）。而角膜表面不规则指数（ｓｕｒｆａｃｅ ａｓｙｍｍｅｔｒｉｃ ｉｎｄｅｘ，ＳＡＩ）值，第１与第

The differences in corneal sbape between myopic and normal eyes

The corneal shapes of 35 eyes with moderate and mild degrees of myopia compared with those of 35 normal eyes were studied by a computerized video keratoscope(TMS-1).The results show that the surface regularity index(SRI),the refractive power at central optical zone,the simulated ker-atoscopic reading(Simk), the average corneal power of zones 3mm,5mm,7mm in diameter centered at the corneal center of the eyes with moderate and mild degrees of myopia are greater than those of the normal eyes (P<0.05 ).However,the surface asymmetry index(SAI), the differences of corneal pow-ers between the first and the 15th ring and between the first and the 25th ring in both groups are of no statistical significant differences (P>0.05).It is suggested that the corneal refractive power of myopic eye be much higher than that of the normal eye,The authors propose the first time that the pathogene-sis of some eyes with moderate and mild myopia may be the increase of corneal refractive power which results from traction of sclera near the limbus due to accommodation and discuss it in detail.