Repeatability and reproducibility of pachymetric mapping with Visante anterior segment-optical coherence tomography

To determine the repeatability and reproducibility of central and peripheral corneal pachymetry mapping with anterior segment-optical coherence tomography (AS-OCT).

An observational cross-sectional study involving two groups: 27 healthy eyes and 20 eyes with keratoconus. Each subject underwent scanning sessions with AS-OCT to determine intraobserver repeatability, interobserver reproducibility, and additionally for healthy eyes, intersession reproducibility for different regions of the cornea up to a 10-mm diameter. Main outcome measures were reproducibility and repeatability coefficients, intraclass correlation coefficients, and coefficients of variation of the average central (0-2 mm), pericentral (2-5 mm), transitional (5-7 mm), and peripheral (7-10 mm) corneal thicknesses generated by the Visante AS-OCT (Carl Zeiss Meditec, Inc., Dublin, CA) pachymetric mapping protocol.

The coefficients of repeatability were less than 2% in healthy subjects and less than 3% in patients with keratoconus. The reproducibility coefficients were less than 2% and 4% in healthy subjects and patients with keratoconus, respectively. There was no significant difference between scans obtained by different observers or during different visits. The intraclass correlation coefficients were greater than 0.99 and 0.97 in healthy subjects and patients with keratoconus, respectively.

With the pachymetric mapping protocol of Visante AS-OCT, these results suggest that central and peripheral corneal thickness measurements in healthy subjects and in eyes with keratoconus are repeatable and reproducible.