Comparative study of three semiautomated specular microscopes.

We compared two clinical video-assisted specular microscopes (Zeiss, noncontact, and the wide-field Keeler Konan sp 3300, contact) with an autofocus microscope (Konan noncon Robo-ca sp 8000, noncontact) with built-in analyzing software by studying the morphometry of the central corneal endothelium of 12 eyes in 12 patients. The mean coefficients of variation of the cell size analysis of three successive images per cornea for the three methods were 3.9%, 4.0%, and 2.2%, respectively. One-way analysis of variance showed a significant difference in the mean cell area measured with the three methods; there was no significant difference in the results of hexagonality (pleomorphism) and coefficient of variation (polymegathism). Although each microscope showed a high reproducibility, we do not recommend using the three interchangeably. The Konan noncon Robo-ca sp 8000 specular microscope provides a rapid morphometric endothelial analysis. The Keeler Konan sp 3300 is better for more detailed studies and photography of the corneal endothelium.