Repeatability and Intersession Reproducibility of Pentacam Corneal Thickness Maps in Fuchs Dystrophy and Endothelial Keratoplasty

Purpose:To assess intrasession repeatability and intersession reproducibility of Pentacam corneal thickness maps in patients with Fuchs endothelial corneal dystrophy (FECD) before and after endothelial transplantation.Methods:In this observational diagnostic evaluation, 20 healthy subjects along with 81 consecutive patients were examined. Patients were classified into 4 groups: FECD without corneal edema, FECD with corneal edema, Descemet stripping automated endothelial keratoplasty, and Descemet membrane endothelial keratoplasty. Three consecutive scans of each eye were obtained at 2 different sessions. Raw pachymetry data were used to calculate average values of 4 concentric annular zones, which were also divided into 8 sectors. Repeatability and reproducibility coefficients (CR), coefficient of variation (CV), intraclass correlation coefficient, and 95% limits of agreement were calculated.Results:The intrasession repeatability CV was 1% in the central 6 mm for all groups, with an intraclass correlation coefficient 0.97. It was better at the central zone than the periphery in all groups. Intersession reproducibility tended to be worse in the central area than the periphery in FECD without edema (CR 24.37; CV 1.48) and FECD with edema (CR 36.74; CV 2.03), whereas it was better in the central area in healthy eyes (CR 20.11; CV 1.32) and improved after Descemet stripping automated endothelial keratoplasty (CR 21.93; CV 1.31) and Descemet membrane endothelial keratoplasty (CR 30.83; CV 1.94).Conclusions:Pentacam corneal thickness maps showed good repeatability and intersession reproducibility in virgin and grafted corneas with FECD, which makes it a valid tool for monitoring these patients. Central areas showed the highest variability between sessions in diseased groups.