Intraobserver Repeatability of Tomographic, Pachymetric, and Anatomical Measurements in Healthy Eyes Using a New Swept-Source Optical Coherence Topographer.

PURPOSE: The purpose of this study was to evaluate the intraobserver repeatability of several corneal parameters in healthy eyes using a new swept-source optical coherence topographer.

METHODS

Fifty right eyes of 50 subjects were enrolled in this study. A single examiner performed 3 consecutive measurements using the Anterion swept-source optical coherence tomography. The following corneal parameters were evaluated: average keratometry (K), steep K, flat K, astigmatism, best fit sphere, and maximum keratometry on the anterior and posterior surfaces at 3 mm, average K, steep K, flat K, and astigmatism in the total corneal power map at 3 mm, central corneal thickness and thinnest point thickness in the pachymetric map, and corneal diameter. To assess the repeatability of the measurements, we calculated the following indexes: intrasubject SD (Sw), coefficient of variation, coefficient of repeatability, and intraclass correlation coefficient (ICC).

RESULTS

High repeatability was reported for all the evaluated corneal parameters, with Sw values lower than 0.027, coefficient of variation values lower than 0.066%, and coefficient of repeatability values lower than 0.187. ICC values showed a high correlation between measurements in all cases, being the lowest value for the astigmatism of the anterior surface (ICC = 0.92); for the rest, ICC values were larger than 0.98. Finally, we have not found statistically significant differences between repeated measurements (P > 0.05).

CONCLUSIONS

The anterior segment measurements provided by the Anterion swept-source optical coherence tomography device show high intraobserver repeatability in healthy eyes.