Comparative Analysis of Tomographic Indicators Forecasting Decompensation in Fuchs Endothelial Corneal Dystrophy

Purpose: To compare the performance of 3 commercially available tomographers (the Pentacam Scheimpflug camera, the swept-source optical coherence tomography Casia, and the blue light slit-scanning tomographer Precisio) in the identification of patterns associated with Fuchs endothelial corneal dystrophy (FECD) decompensation. Methods: This was a clinic-based cross-sectional imaging study. Pachymetry maps and posterior surface elevation maps were acquired with the 3 devices from 61 eyes affected by FECD. The maps were graded according to the evidence of tomographic patterns predictive of FECD decompensation (loss of parallel isopachs, displacement of the thinnest point, and focal posterior depression) by 2 blind cornea specialists. Results: The loss of parallel isopachs was significantly less frequently evident in Pentacam pachymetry maps 8%, 95% confidence interval (CI) (3%, 18%) compared with both the Casia 31%, 95% CI (20%, 44%), P = 0.01 and Precisio devices 24%, 95% CI (15%, 37%), P = 0.05. The displacement of the thinnest point was graded as most evident in a significantly higher proportion of Precisio pachymetry maps 43%, 95% CI (31%, 55%) compared with both the Pentacam 13%, 95% CI (6%, 24%), P = 0.001 and Casia devices 21%, 95% CI (12%, 33%), P = 0.03. There were no significant differences in the identification of focal posterior depression on posterior elevation maps across the 3 devices. Conclusions: Identification of patterns predictive of FECD prognosis on pachymetry and posterior elevation maps is possible with different devices. However, their evidence varies across tomographers, and the results from different devices are not interchangeable.