Repeatability assessment of anterior segment biometric measurements under accommodative and nonaccommodative conditions using an anterior segment OCT.

Abstract

As accommodation is a dynamic process changing anterior ocular structures, we aim to compare the repeatability between the biometric measurements taken with and without accommodation. Thirty healthy right eyes were measured in a baseline and an accommodative state using Visante-OCT. Three repeated measurements were taken to obtain central corneal thickness (CCT), anterior chamber depth (ACD), angle-to-angle distance (ATA), iridocorneal angles (IA), and crystalline lens thickness (LT). Repeatability was evaluated by the calculation of coefficient of repeatability (CoR), coefficient of variation (CoV), and intraclass correlation coefficient (ICC). In addition, the Passing-Bablok regression method was applied. For the nonaccommodative state, the CoR for CCT, ACD, ATA, and LT was 20.02μm, 0.09mm, 0.25mm, and 0.12mm respectively. The CoR for CCT, ACD, ATA, and LT in the 6D-accommodative state was 20.85μm, 0.08mm, 0.26mm, and 0.14mm respectively. IA had similar results for both states; the CoR ranged between 3 and 4°, CoV was less than 4%, and the ICC was between 0.984-0.988. There were no significant differences between the three repeated measurements for any measurement. Visante-OCT provides good repeatability for anterior segment measurements for both accommodative and nonaccommodative states.