Gaussian power with cylinder vector field representation for corneal topography maps.

The corneal maps displayed on commercially available corneal topography instruments are really one-dimensional, defining quantities only along a meridian, and ignoring shape information along any other direction. Both axial and instantaneous power have the drawbacks that there is a singularity at the center data point on the videokeratograph axis, and the computed powers and appearance of the corneal map change depending on the videokeratograph axis or on the location of asymmetries. We propose a new representation for corneal topography maps, Gaussian power with cylinder vector field, that has no singularity, and faithfully produces power values and corneal map patterns that are independent of videokeratograph axis or location of asymmetries.