Comparison of corneal thickness measured using the new Revo FC optical coherence tomographer and the pentacam Scheimpflug-based imaging system

Corneal thickness is a key measurement in ophthalmology, playing a significant role in diagnosing and monitoring conditions such as keratoconus, corneal dystrophies, and glaucoma, as well as in the preoperative evaluation for refractive surgery and keratoplasty. This study aimed to compare corneal thickness measurements obtained using a Scheimpflug-based imaging system with a new optical coherence tomographer. This prospective study enrolled Polish patients with healthy eyes. Measurements were performed using the two devices, the Oculus Pentacam and Optopol Revo FC, in a random sequence. The agreement between the devices was evaluated using correlation coefficients, Bland-Altman analysis, and a paired t-test. A total of 74 patients were examined. The central corneal thickness measured by Pentacam was 545.52 ± 30.16 μm, while 539.36 ± 30.16 μm for Revo FC (difference 5.52 μm; 95% CI: 4.42 to 6.61; p < 0.01). The thinnest corneal location measured by Pentacam was 540.93 ± 30.20 μm, while 531.04 ± 30.24 μm for Revo FC (difference 9.27 μm; 95% CI: 7.29 to 10.76; p< 0.01). However, the strong intraclass correlation coefficients (0.99 for central and 0.98 for minimum corneal thickness) indicate a high level of agreement between the two imaging systems. This study demonstrated that corneal thickness measurements with Pentacam were greater than with Revo FC OCT. Although highly correlated, the results cannot be considered interchangeable as the mean differences exceeded clinically acceptable limits.