Clinical significance of tear menisci in dry eye

To determine the relationships among tear menisci variables and clinical tests used in the diagnosis of dry eye patients.

Dry eye patients (n=50; age, 35.2 years) and healthy subjects (n=48; age, 33.3 years) were recruited. Upper and lower tear menisci were imaged noninvasively by optical coherence tomography (OCT) immediately after normal and delayed blinking in both eyes. Tear meniscus heights, areas, and radius of curvatures were obtained by custom software. Tear film break-up time was measured by fluorescein (fluorescein film tear break-up time, FTBUT) and tearscope (noninvasive tear film break-up time), ocular surface vital staining was evaluated with fluorescein (FS), and secretion was measured by Schirmer I test without and with anesthesia.

In dry eye patients, all lower tear meniscus variables during normal blinking were correlated with all clinical tests except Schirmer I test without anesthesia. Upper tear meniscus variables were correlated with FTBUT and Schirmer I test with anesthesia. During delayed blinking, upper and lower tear menisci variables were correlated with Schirmer I test without anesthesia and FS; however, there were no correlations between menisci variables and FTBUT or Schirmer I test with anesthesia. In healthy subjects, only lower meniscus variables were correlated with Schirmer I test with anesthesia during normal blinking. During delayed blinking, the lower meniscus variables were correlated with only the Schirmer I test without anesthesia.

Lower tear menisci were correlated more strongly with the clinical tests than were upper menisci. The tear menisci were associated with the basic tear secretion during normal blinking. Delayed blinking may affect reflex tearing levels.