Tear Meniscus Evaluation by Anterior Segment Swept-Source Optical Coherence Tomography

Abstract

To investigate the repeatability of tear meniscus measurements using anterior segment swept-source optical coherence tomography (OCT) and the relationship of tear meniscus measurements with tear film breakup time and Schirmer test results. Prospective, observational, cross-sectional study. We enrolled 26 healthy subjects (26 eyes; 20 men and 6 women; mean age, 36.5 ± 6.8 years) at the University of Tokyo School of Medicine, Tokyo, Japan, in this study. Examinations were conducted in the following sequence: anterior segment vertical raster scans by swept-source OCT, tear film breakup time, and Schirmer test. Each subject underwent OCT measurements twice by the same grader, and the central upper and lower tear menisci height and area and the lower tear meniscus volume were examined. Each OCT image was evaluated by 2 masked graders using the software calipers. The average upper and lower tear meniscus heights were 231 ± 78μm and 256 ± 57μm, respectively, and the average upper and lower tear meniscus areas were 18 829 ± 7823μm(2) and 21 903 ± 8173μm(2), respectively. The average tear meniscus volume was 0.1327 ± 0.051mm(3). The intergrader intraclass correlations for all the parameters were more than 95%. The OCT tear meniscus measurements and the Schirmer test scores were correlated significantly (P < .05, Spearman nonparametric correlation analysis). However, tear film breakup time was not correlated significantly with any of the parameters of tear menisci (P > .05). Anterior segment swept-source OCT is a noninvasive and practical method that can be used for quantitative evaluation of tear fluid.