Correlation between quantitative measurements of tear film lipid layer thickness and meibomian gland loss in patients with obstructive meibomian gland dysfunction and normal controls

Purpose: To evaluate the correlation between tear film lipid layer thickness and other objective measurements such as tear film break-up time (TBUT), upper and lower meibomian gland losses, and Schirmer 1 test in patients with obstructive meibomian gland dysfunction (MGD) and normal controls. Design: Cross-sectional study. Methods: Thirty eyes of 30 patients with obstructive MGD and 25 eyes of 25 normal controls were enrolled. Lipid layer thickness was measured using an interferometer. Tear film stability and tear production were evaluated by TBUT and Schirmer 1 test. Upper and lower meibomian gland losses were evaluated using noncontact meibography. The correlations among variables were evaluated in the obstructive MGD group and the control group. Results: TBUT was significantly shorter in the obstructive MGD group than in the control group (P < .001). Upper and lower meibomian gland losses were higher in the obstructive MGD group than in the control group (P <.001 and P <.001, respectively), and lipid layer thickness was significantly thicker in the control group than in the obstructive MGD group (P = .028). Lipid layer thickness was significantly negatively correlated with upper and lower meibomian gland losses in both groups. Conclusions: Lipid layer thickness objectively measured with the interferometer was significantly thicker in the control group than in the obstructive MGD group. Lipid layer thickness was negatively correlated with upper and lower meibomian gland losses in the control group as well as in the obstructive MGD group.