Prediction model for best focus, power, and spherical aberration of the cornea: Raytracing on a large dataset of OCT data.

Raytracing improves on linear Gaussian optics by considering the asphericity of both refracting surfaces and using Snell's law of refraction in preference to paraxial simplifications. However, there is no unique definition of best focus, and therefore the calculated corneal power varies depending on the definition of best focus. The multivariate linear model enabled more precise estimation of corneal power compared to the simple keratometer equation.