Quantitative descriptors of corneal topography. A clinical study
S. E. Wilson and S. D. Klyce
Louisiana State University Medical Center School of Medicine, New Orleans.
Quantitative descriptors of corneal topography determined by computerized
algorithm and designed to augment the information derived from topographic
maps were evaluated in a clinical study. The surface regularity index, a
measure of central corneal optical quality, was highly correlated with best
spectacle-corrected visual acuity (rho = 0.80, P less than .001). The
relatively low correlation between the surface asymmetry index, a measure
of central corneal asymmetry, and best spectacle-corrected visual acuity
(rho = 0.62, P less than .005) suggests that corneal symmetry is a lesser
but still important determinant of the optical performance of the anterior
corneal surface. There was also a high correlation between factors
determined from computer-generated orthogonal simulated keratometer values
and clinical keratometry values (mean corneal power, total corneal
cylinder, and the location of the steepest corneal meridian). The
information derived from these algorithms has both clinical and research
applications and can be incorporated into computer-assisted topographic
analysis systems.
