Evaluation of Lipid Layer Thickness Measurement of the Tear Film as a Diagnostic Tool for Meibomian Gland Dysfunction

Purpose:The LipiView interferometer (TearScience Inc, Morrisville, NC) is capable of delivering quantitative values of the tear-film lipid layer thickness (LLT). The purpose of this study was to investigate whether there is a correlation between the LLT and other diagnostic criteria for Meibomian gland dysfunction (MGD).Methods:We performed a retrospective analysis of 110 patients (199 eyes) from our dry eye clinic. Subjective symptoms, break-up time (BUT), expressible Meibomian glands, and LLT were measured.Results:There was a significant correlation between expressible Meibomian glands and LLT (r = 0.36, P < 0.0001). Also, a possible trend of inverse correlation between subjective symptoms (standard patient evaluation of eye dryness) and the LLT was observed; however, this was not significant (r = -0.13, P < 0.08). Analysis of the whole study collective revealed no correlation between the BUT and the LLT (r = 0.003, P = 0.97). A subgroup analysis of the patients with an LLT 60 showed a better correlation between the LLT and the BUT, which was marginally not significant (r = 0.21; P = 0.059). For a cut-off value of 75-nm LLT, we found a sensitivity of 65.8% and a specificity of 63.4% for the detection of an MGD. For a cut-off value of 60, the sensitivity was 47.9%, and the specificity was 90.2%.Conclusions:The positive correlation between the LLT and expressible meibomian glands found in this study suggests a higher probability of MGD in patients with a low LLT. This automated assessment of the LLT might be a suitable screening test for detecting MGD. However, further prospective studies are needed to confirm these results and to identify potential confounders.