Assessment and reproducibility of anterior chamber depth measurement with anterior segment optical coherence tomography compared with immersion ultrasonography.

Purpose: To measure anterior chamber depth (ACD) with an anterior segment optical coherence tomography (AS-OCT) and a standard ultrasonic (US) axial scan (A-scan) device using an immersion technique and to assess repeatability, reproducibility, and correlations of the measurements.

Setting: Department of Ophthalmology, Medical Health and Science Center, University of Debrecen, Debrecen, Hungary.

Methods: Sixty healthy eyes of 41 patients were enrolled in a study. The central ACD was measured 5 times with AS-OCT (Visante, Carl Zeiss Meditec) using its chamber tool and 5 times with a US A-scan device (UltraScan Imaging System, Alcon Laboratories) using an immersion method. The measurements were performed consecutively by 2 independent observers.

Results: The mean ACD measured with AS-OCT was 3.12 mm +/- 0.33 (SD) by observer 1 and 3.11 +/- 0.33 mm by observer 2 (P = .78). The repeatability was 0.8% +/- 0.4% and 1.9% +/- 1.4%, respectively. The reproducibility was 0.23%. The reliability coefficient with AS-OCT was 99.6%. The mean ACD measured with immersion US A-scan was 2.98 +/- 0.33 mm by observer 1 and 2.95 +/- 0.34 mm by observer 2 (P = .68) . The repeatability was 6.4% +/- 3.8% by observer 1 and 8.5% +/- 4.9% by observer 2. The reproducibility was 0.88%. The reliability coefficient was 87.1% for US A-scan measurements. The difference between ACD values with AS-OCT and values with US A-scan was statistically significant (P = .02). The correlation (r) between AS-OCT and US A-scan was 0.732 (P<.0001) by observer 1 and 0.802 (P<.0001) by observer 2.

Conclusions: Anterior chamber measurements were significantly deeper with AS-OCT than with US immersion A-scan. Repeatability of ACD measurements was better with AS-OCT than with immersion US, and reproducibility was equal with the 2 methods.