The relation between blinking and conjunctival folds and dry eye symptoms.
OBJECTIVE
To investigate the relationship between blink action, dry eye symptoms, and lid-parallel conjunctival folds (LIPCOF).


METHODS
In 30 subjects (14 were women; mean [standard deviation {SD}] age, 42.4 [±12.3] years), spontaneous blinks were recorded from a temporal-inferior view (high-speed video), and the blink extent (incomplete [IC], almost complete [AC], and complete [CC]) was evaluated. Dry eye symptoms were evaluated using the Ocular Surface Disease Index (OSDI), and nasal and temporal LIPCOF grades were noted. Correlations between groups were calculated with Pearson correlation (or Spearman rank in nonparametric data), and differences between groups were calculated with an unpaired t-test (or U-test Mann-Whitney in nonparametric data).


RESULTS
Blink rate was significantly higher in females (22.0% [±16.8]) than in males (8.6% [±7.2]; unpaired t-test: p = 0.007). The percentage of AC of all blinks (AC%) was significantly correlated to LIPCOF sum (nasal + temporal) and OSDI scores (r > 0.570, p < 0.001). The percentage of IC was significantly correlated to LIPCOF sum (r = -0.541, p < 0.001) but not to OSDI.


CONCLUSIONS
The frequency and type of blinking may have an effect on dry eye symptoms and LIPCOF severity since almost all complete blinks were significantly related to both factors.
*MSc, PhD, FAAO †Dipl Ing(FH) ‡PhD, FAAO Dr. Heiko Pult - Optometry and Vision Research (HP, BHR-P), Weinheim, Germany; Contact Lens and Anterior Eye Research Unit (HO, PJM), School of Optometry and Vision Sciences (HP, BHR-P), Cardiff University, Cardiff, Wales, United Kingdom; and School of Optometry and Vision Science (PJM), University of Waterloo, Ontario, Canada.
Heiko
H
Pult
Britta H
BH
Riede-Pult
Paul J
PJ
Murphy
D000328:Adult; D001767:Blinking / Q000502:physiology*; D003229:Conjunctival Diseases / Q000503:physiopathology*; D015352:Dry Eye Syndromes / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D011795:Surveys and Questionnaires; D014741:Video Recording