Videokeratography.

Our ability to assess corneal topography has improved tremendously in the last 10 years. Current placido disk-based videokeratography units have made the process of image analysis simple, yet current systems are not perfect in their quantitative assessment of human corneas. The choice of a system depends on the user's needs and the evaluation of the differences in hardware, software, format of data output, service, frequency of software updates, user friendliness, and control of focusing errors. This article reviews the development of technology for assessing corneal topography.