Edmund C
Acta Ophthalmol (Copenh). 1986 Feb;64(1):97-100. doi: 10.1111/j.1755-3768.1986.tb06880.x.
With the photokeratoscope of Wesley-Jessen, 45 pictures were taken from the right eye of 18 normal persons and analysed by 2 different methods. The first method is based on the assumption that radius of the corneal curvature is constant between 2 points of reflection, the second method is without such a preliminary assumption on the corneal contour. The parameters estimated: radius of the central curvature (K) and the coefficient of radius variation (RV) are compared. A difference in K at 1.5% corresponding in case to 0.6 diopters and a difference in RV at 46% are demonstrated. The differences are correlated to the error introduced by the assumption on constant radius. Further it is established that K measured by the keratometer of Javal-Schiøtz is about 0.14 mm larger (in case 0.7 diopters) than K estimated by the method of photokeratoscopic data analysis without preliminary assumption.
使用卫斯理-杰森角膜照相仪，从18名正常人的右眼拍摄了45张照片，并采用两种不同方法进行分析。第一种方法基于这样的假设，即角膜曲率半径在两个反射点之间是恒定的；第二种方法则不对角膜轮廓做此类初步假设。对所估计的参数：中央曲率半径（K）和半径变化系数（RV）进行了比较。结果显示，K的差异为1.5%，相当于0.6屈光度，RV的差异为46%。这些差异与恒定半径假设所引入的误差相关。此外还确定，用贾瓦尔-席茨角膜曲率计测量的K值比未做初步假设的角膜照相数据分析方法所估计的K值大约0.14毫米（相当于0.7屈光度）。
