Abstract
Purpose:
To investigate the dynamics of tear meniscus after instillation of eye drops using anterior segment swept source optical coherence tomography (SS-OCT).
Methods:
Twenty-three eyes of 23 volunteers were enrolled (19 males, 4 females; mean age 34.5±5.9 years) in this study. Examinations were conducted in the following sequence; anterior segment vertical raster scans by SS-OCT, vital staining scores, tear film break up time (BUT), and Schirmer’s test. After the baseline measurements, 40 µl saline on one eye and 40 µl of either 0.1% sodium hyaluronate, 0.3% sodium hyaluronate, or 2% rebamipide was instilled on the fellow eye of ten subjects each. Lower tear menisci height (TMH), area (TMA), and the lower tear meniscus volume (TMV) were examined using SS-OCT at 30 seconds, 1,3,5,10,15, and 20 minutes post instillation. On each image within the range of 5mm to 11mm, outlines of TMA were plotted manually, and then TMV was automatically computed by integration analysis based on the computer program.
Results:
The average BUT was 6.9±2.5 seconds, Schirmer test value was 14.9±12.3 mm, and the vital staining score was 0.3±0.5 points. A significant increase in tear meniscus measurements by SS-OCT was observed until 1 minute post instillation of saline, 3 minutes for 0.1% sodium hyaluronate, 10 minutes for 0.3% sodium hyaluronate, and 5 minutes for rebamipide, compared to the baseline levels (p<0.05, paired t-test). As compared with saline, tear meniscus measurements were significantly higher until 30 seconds, 1 minute, and 5 minutes after instillation of 0.1% sodium hyaluronate, rebamipide, and 0.3% sodium hyaluronate, respectively (p<0.05).
Conclusions:
SS-OCT is a noninvasive and practical method for quantitative evaluation of tear fluid. Efficacy of eye drops could possibly be assessed by observation of tear fluid dynamics using SS-OCT.
Keywords: 421 anterior segment •
486 cornea: tears/tear film/dry eye