Busin M, Wilmanns I, Spitznas M
Universitäts-Augenklinik, Sigmund-Freud-Strasse, Federal Republic of Germany.
Graefes Arch Clin Exp Ophthalmol. 1989;227(3):230-6. doi: 10.1007/BF02172754.
The analysis of corneal topography has recently become popular, mainly as a consequence of the rapid development of refractive surgery techniques. To date, computer-assisted evaluation of photokeratoscope pictures has been the most popular method used to assess corneal topography. The processing system described previously by other authors requires hand-digitizing of the photokeratoscope pictures and therefore the constant presence of an operator for a considerable amount of time. We have introduced the use of a video camera to digitize the photokeratoscope images, making the processing automatic and quicker. Moreover, precision glass spheres have been used to calibrate the system in order to minimize the intrinsic errors even further. The data obtained from the computerized analysis are presented in three different ways. Besides having the numerical values in diopters, corneal maps with various shades of grey are used, together with the quantitative, three-dimensional representation of corneal astigmatism. An automated system for the analysis of corneal topography was tested for both experimental models and clinical conditions. It was easy to use and showed high precision (less than 1% error when processing photographs of precision glass spheres).
角膜地形图分析近来颇受欢迎，这主要是屈光手术技术迅速发展的结果。迄今为止，计算机辅助评估角膜照相图片一直是用于评估角膜地形图的最常用方法。其他作者先前描述的处理系统需要对角膜照相图片进行手工数字化处理，因此需要操作人员长时间持续在场。我们引入了使用摄像机对角膜照相图像进行数字化处理的方法，使处理过程自动化且更快。此外，还使用了精密玻璃球体对系统进行校准，以进一步将固有误差降至最低。从计算机化分析中获得的数据以三种不同方式呈现。除了有屈光度的数值外，还使用了带有各种灰度的角膜地图，以及角膜散光的定量三维表示。一种用于角膜地形图分析的自动化系统在实验模型和临床条件下均进行了测试。它易于使用，并且显示出高精度（处理精密玻璃球体照片时误差小于1%）。
