Open-access operating algorithms for commercial videokeratographer and improvement of corneal sampling

We present an algorithm to process images of reflected Placido rings captured by a commercial videokeratoscope. Raw data are obtained with no Cartesian-to-polar-coordinate conversion, thus avoiding interpolation and associated numerical artifacts. The method provides a characteristic equation for the device and is able to process around 6 times more corneal data than the commercial software. Our proposal allows complete control over the whole process from the capture of corneal images until the computation of curvature radii.

The authors would like to acknowledge the financial support of the Spanish Ministerio de Ciencia e Innovación through the project BIA2011-22704, the Generalitat Valenciana through the project PROMETEO/2011/021, and the University of Alicante through the project GRE10-09. A. B. Roig thanks Fundación Cajamurcia for the grant “Beca de investigación Cajamurcia 2010.”