Abstract
Purpose::
The aim was to study the impact of blink on tear dynamics using optical coherence tomography (OCT).
Methods::
One randomly selected eye of 21 subjects (10 women and 11 men, mean age: 32.1 ± 8.7 years) was imaged at the same time of day on two consecutive days. Dimensional information of the tear film and tear menisci of the upper and lower eyelids was obtained during normal and prolonged blinking.
Results::
: No significant changes of all measured variables were found between two repeated visits (ANOVA, P>0.05). Tear film thickness changed (ANOVA, P<0.05) with an increase after blinks (post hoc, P<0.05) and decrease (post hoc, P<0.05) after open eye period. There were differences of upper tear meniscus height (UTMH) and area (UTMA) between normal and prolonged blinks (ANOVA, P<0.05) with significant greater UTMH and UTMA during prolonged blinks (post hoc, P<0.005). Significantly smaller UTMH and UTMA immediately after eye opening were found compared to that before the next eye closure (post hoc, P<0.005). A decrease of the lower tear meniscus (LTMH) after blinking was found compared to that before blinking (post hoc, P<0.05) during prolonged blinks. After the period of eye opening, increases of LTMH and the lower tear meniscus area were found significantly during prolonged blinks (post hoc, P<0.01).
Conclusions::
OCT appears to be a promising tool for studying the impact of blink on tear dynamics. This study was supported by research grants from NEI (R03 EY016420), Allergan and the challenging grant from Research to Prevent Blindness (RPB).
Keywords: cornea: tears/tear film/dry eye