Advances in the analysis of corneal topography.

Recent advances in topographic analysis have provided powerful tools for detecting subtle, but clinically significant, alterations of corneal contour. This article compares keratometry, keratoscopy, and computer-assisted topographic analysis and provides specific examples of the sensitivity of computer-assisted systems in revealing topographic alterations that were not previously discernable. Quantitative descriptors of corneal topography such as the surface asymmetry index, the surface regularity index, and simulated keratometry value augment the information provided by color-coded topographic maps.