Standard vs. Automated Keratometry.

The following is a study investigating the ability of two different keratometers to predict astigmatic refractive error. The keratometers being investigated are the Bausch and Lomb Keratometer and the Humphrey model 410 Autokeratometer. These instruments utilize
very different mechanisms in measuring the curvature of the cornea. Because of the differing mechanisms, it may be possible that the corneal astigmatism measured by each instrument may correlate differently with the subjective astigmatic refractive error of a given eye.
The purpose of this study is to determine if either one of these instruments is a better predictor of astigmatic refractive error. Before detailing the experimental method, apropriate background information will be discussed.