Repeatability, reproducibility, and agreement of central anterior chamber depth measurements in pseudophakic and phakic eyes: Optical coherence tomography versus ultrasound biomicroscopy

PURPOSE: To evaluate the intraexaminer repeatability, interexaminer reproducibility, and agreement of central anterior chamber depth (ACD) measurements obtained by anterior segment optical coherence tomography (AS-OCT) and ultrasound biomicroscopy (UBM) in pseudophakic eyes and phakic eyes. SETTING: Eye Hospital, Wenzhou Medical College, Wenzhou, Zhejiang, China. METHODS: In this prospective study, the central ACD in right pseudophakic eyes and right phakic eyes was measured with the Visante AS-OCT system and the OTI-Scan HF 35-50 UBM system. Intraexaminer repeatability and interexaminer reproducibility were evaluated in a subgroup of eyes from each group. The repeatability and reproducibility of the measurements were evaluated using intraclass correlation coefficients (ICCs) and the Bland-Altman method. RESULTS: The mean ACD in the 70 pseudophakic eyes was 3.91 mm +/- 0.29 (SD) by AS-OCT and 3.76 +/- 0.33 mm by UBM and in the 70 phakic eyes, 2.97 +/- 0.31 mm and 2.90 +/- 0.32 mm, respectively. The 95% limits of agreement between the 2 methods were 0.32 to 0.62 mm in pseudophakic eyes and -0.11 to 0.25 mm in phakic eyes. The ICC for the repeatability and reproducibility of AS-OCT and UBM measurements was high (range 0.985 to 0.996). CONCLUSIONS: Both AS-OCT and UBM ACD measurements showed good repeatability and reproducibility. However, the agreement was better in phakic eyes than in pseudophakic eyes. Thus, the measurements should not be used interchangeably in pseudophakic eyes.