Unified approach to tear film surface analysis with high-speed videokeratoscopy

Placido disk videokeratoscopy, when used in a dynamic acquisition mode, can be utilized for noninvasive assessment of tear film quality. The different commercially available videokeratoscopes that incorporate an automatic option to evaluate tear film do not provide consistent measurements due to differences in their designs as well as differences in the algorithms used to analyze the images. Here, a standardized algorithm that can be applied to different instruments is developed. Results show that, by applying the proposed methodology in two different videokeratoscopes, the agreement among the estimated tear film parameters considerably improves. This represents a step forward in the normalization of tear film assessment.