Agreement between Two Biometers for Central Corneal Thickness Measurement in High Myopia Patients

In refractive surgery, the measurement of Central Corneal Thickness (CCT) is a critical factor in the preparation and screening of surgery to correct myopia. CCT measurements can be measured by optical biometers, including the Scheimpflug camera and Swept-source Optical Coherence Tomography (SS-OCT).

This study aimed to compare the Central Corneal Thickness (CCT) measurements made with Swept-source Optical Coherence Tomography (SS-OCT)-based biometers and the Scheimpflug camera in patients with high myopia.

An analytical cross-sectional study was performed to evaluate the agreement between Central Corneal Thickness (CCT) values obtained using Swept-source Optical Coherence Tomography (SS-OCT) and the Scheimpflug camera. We included a total of 28 individuals with high myopia, including 44 eyes, for our study. These patients underwent Central Corneal Thickness (CCT) tests using both Swept-source Optical Coherence Tomography (SS-OCT) and the Scheimpflug camera. The Bland-Altman test was used to assess the agreement between the two devices.

Forty-four eyes with axial lengths ranging from 26.05 to 34.02 mm based on SS-OCT examinations were included in this study. The mean CCT was 527.59 ± 35.710 (p <0.05) μm and 525.64 ± 35.421 μm (p <0.05), based on SS-OCT and the Scheimpflug camera, respectively. The Bland-Altman plot revealed good agreement between both devices, with a mean difference of 2.3409 μm; however, a 95% limit of agreement demonstrated a wide range, ranging from -8.48509 to 12.39400 μm at a 95% confidence interval.

CCT measurements using SS-OCT and the Scheimpflug camera differed significantly among patients with high myopia. Our findings have suggested that CCT measurements made with either device should be interpreted with caution and not be used interchangeably.