Computer-assisted corneal topography. High-resolution graphic presentation and analysis of keratoscopy.

Keratoscopy is a useful clinical tool for the evaluation of topographic abnormalities of the corneal surface. However, not all the detailed information presented by keratoscope photographs is assessed easily by visual inspection. A computer-based analysis system therefore was developed to assist in the clinical interpretation of keratoscope images. With this system, deviations from sphericity are displayed in graphic form to aid in the recognition of abnormalities, and surface powers are presented in tabular form. Human eyes that are emmetropic, and eyes with keratoconus and severe astigmatism were analyzed. This process provides a useful quantitative method with which to determine corneal shape, as well as a useful adjunct to the clinical evaluation and teaching of keratoscopy. In addition, such a quantitative analysis may provide the basis for the development of new techniques for the correction of visual distortion caused by corneal surface irregularities.