Abstract:

Objective To assess the agreement of central corneal thickness (CCT) measured by anterior chamber-optical coherence tomography(AC-OCT) and ultrasonic pachymeter and provide an objective basis for clinical application of  AC-OCT. Methods CCT of 150 college student volunteers (300 eyes) measured by two devices were obtained. The data was analyzed by paired t test and Pearson correlation analysis. Bland-Altman plot and Mountain plot were used to assess the agreement. Results The mean CCT values were（530.05±33.611） μm measured by AC-OCT and （543.68±35.088）μm measured by ultrasonic pachymeter. Regression analysis showed a high correlation between the values obtained by both devices (r=0.960, P<0.001). Compared with AC-OCT, ultrasonic pachymeter overestimated the CCT by a mean of 13.62 μm. The two modalities had incomparable results. Conclusion It is important to be noted in clinical practice that the measurements acquired by these two modalities are not directly interchangeable. However, the CCT measurements by the AC-OCT and ultrasonic pachymeter are highly correlated. AC-OCT is an effective method to observe the changes of the corneal thickness in the long term.

Key words: central corneal thickness, ultrasonic pachymeter, anterior chamber -optical coherence tomography