Investigation of Tear Lipid Layer Patterns According to Blinking among Dry Eye Patients

Purpose: To investigate tear lipid layer patterns according to blinking using an interferometer for dry eye patients. Methods: We retrospectively reviewed the medical records of 132 patients who underwent dry eye disease-related evaluation, including LipiView^®, between August 2018 and January 2020. Data including past history, slit-lamp examination, tear film break-up time, Schirmer, Oxford score grading, lipid layer thickness (LLT), number of blinks, and tear lipid layer patterns according to blinking were collected. We subdivided dry eye as meibomian gland dysfunction (MGD), aqueous deficiency dry eye (ADDE), and combined ADDE/MGD (Combine); we also classified the tear lipid layer patterns as uphill, flat, downhill, and mix. Results: The numbers of patients in each tear lipid film pattern were as follows; uphill 45, flat 16, downhill 53, and mix 18. The statistically significant clinical characteristics among the four patterns were Oxford score (p = 0.001), LLT (p = 0.019), number of blinks (p = 0.001), number of partial blinks (p = 0.013), and the partial/total blinks ratio (p = 0.001). The most common pattern for MGD was downhill 44.7%; for Combine, downhill 40.7% and uphill 35.8%; and for ADDE, uphill 38.5%. Conclusions: The tear lipid layer graph patterns according to blinking using LipiView^® were associated with the number of blinks, the partial/total blink ratio, and LLT.