Repeatability and Agreement of Two Swept-Source Optical Coherence Tomographers for Anterior Segment Parameter Measurements.

ABSTRACT

PURPOSE: The aim was to evaluate the repeatability and agreement of two swept-source optical coherence tomographers for anterior segment parameters in healthy subjects. PATIENTS AND METHODS: Automated mark of scleral spur and angle recess for the CASIA2 and manual mark of scleral spur and angle recess for the Anterion were performed, and then the measurement values of the related parameters were automatically generated. Subjects with pupil diameter (PD) differing by <15% between the 2 devices were included. PD, lens vault (LV), anterior chamber depth (ACD), angle to angle distance (ATA), anterior chamber width (ACW), anterior chamber angle (ACA), angle opening distance (AOD), and trabecular iris space area (TISA) were measured in the horizontal images with both CASIA2 and Anterion. Intraclass correlation coefficient (ICC) was used to evaluate intradevice repeatability. Bland-Altman plots were performed to assess the agreement between the 2 devices. RESULTS: Thirty-five right eyes of 35 subjects were included with a mean age of 25.60±3.00 years. The CASIA2 showed moderate to good intradevice repeatability (ICCs ranged from 0.786 to 0.989) whereas the Anterion showed good intradevice repeatability (ICCs ranged from 0.921 to 0.998) for anterior segment parameters. Compared with the CASIA2, the Anterion offered larger values of ACA500/750, AOD500/750, and TISA500/750 but smaller values of PD, LV, ACD, ATA, and ACW. Good agreement for PD, ACD, ATA, and ACW was detected with 95% limits of agreement of -1.02 to 1.02 mm, -0.11 to 0.14 mm, -0.17 to 0.19 mm, -0.13 to 0.28 mm, respectively. Poor agreement for LV, ACA500/750, AOD500/750, and TISA500/750 was achieved with the 2 devices. CONCLUSIONS: Anterion outperformed CASIA2 on intradevice repeatability. While agreement was noted for some parameters using manual Anterion and automated CASIA2 approaches, poor agreement of LV and angle parameters indicates that measurements from these optical coherence tomography devices should not be considered interchangeable.