Variability in Corneal and Epithelial Pachymetry: A Comparison of Optopol Revo 130 and Optovue RTV XR Avanti in Healthy Patients

<b>Background/Objectives:</b> The accurate measurement of corneal epithelial thickness (CET) and pachymetry is essential for diagnosing and managing corneal conditions such as keratoconus and for optimizing outcomes in refractive surgery. This study aimed to evaluate the agreement and repeatability of measurements between two anterior segment optical coherence tomography (AS-OCT) devices-OCT REVO FC 130 and Optovue RTV XR Avanti-in healthy individuals. <b>Methods:</b> This prospective, cross-sectional, observational study included 53 healthy participants. High-quality scans were performed using both devices by two trained operators. Agreement between devices was assessed using Bland-Altman analysis and Deming regression, while repeatability and reproducibility were evaluated through intraclass correlation coefficients (ICCs) and test-retest variability (TRT). <b>Results:</b> Both devices demonstrated high repeatability and reproducibility across central and peripheral zones, with ICCs exceeding 0.98 for central pachymetry and stroma measurements. Repeatability and reproducibility were slightly higher for the OCT REVO FC 130 compared to the Optovue RTV XR Avanti, particularly for central measurements. Bland-Altman analysis revealed a mean difference near zero with narrow limits of agreement for most parameters, indicating strong inter-device agreement. Variability in CET measurements was higher, potentially due to the inclusion of tear film in OCT segmentation. <b>Conclusions:</b> The OCT REVO FC 130 and Optovue RTV XR Avanti offer comparable reliability and precision for corneal thickness measurements in healthy eyes, with the REVO demonstrating slightly better repeatability and reproducibility. These findings support the use of either device in clinical practice and research for corneal assessment.