Relationship between the partial blink rate and ocular surface parameters.

Purpose: To elucidate the relationship between partial blink rate (PBR) and ocular surface parameters.

Methods: We conducted a retrospective cross-sectional study of the patients who visited the Kim's Eye Hospital between March 2020 and July 2020. Blinking dynamics, tear film lipid layer thickness (LLT), non-invasive tear film break- up time (NITBUT), tear meniscus height (TMH), and meibomian gland (MG) dropout rate were assessed using the IDRA Ocular surface analyzer (SBM SISTEMI, Inc., Torino, Italy) (IDRA). Dry eye symptoms were quantified by the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire scores.

Results: A total of 47 non-Sjögren dry eye patients (47 right eyes, mean age = 56.8 ± 14.5 [20-75] years, 66% female) were enrolled. Among the ocular surface parameters, PBR had strong correlations with MG dropout rate (r = 0.811; p < 0.01) and moderate correlations with SPEED scores (r = 0.596; p < 0.01). MG dropout rate and age had moderate correlations with SPEED scores (r = 0.416; p = 0.04 and r = 0.322; p = 0.03, respectively). Comparisons by sex revealed no significant difference in characteristics, except for the TMH value. The TMH of female patients (0.17 ± 0.07) was significantly higher than that of males (0.14 ± 0.04; p = 0.04). LLT showed no significant correlation with the other variables.

Conclusion: PBR and MG dropout rates measured with IDRA were significantly correlated to dry eye symptoms.