Purpose: To determine (1) if the number of meibomian glands yielding liquid secretion (MGYLS) is correlated with dry eye symptoms and (2) the mean number of MGYLS in the nasal, central, and temporal regions of the lower eyelid in a random clinical sample.
Methods: Subjects presenting for routine eye examinations were recruited (n = 133; 90 females, 43 males; mean age = 50.3 ± 14.7 years). The sample included symptomatic and asymptomatic individuals using the Standard Patient Evaluation of Eye Dryness questionnaire. Meibomian gland evaluations were performed using a standardized technique and diagnostic instrument.
Results: The mean number of MGYLS in the lower eyelid correlated with dry eye symptoms, p = 0.0002. The mean numbers of MGYLS in each third of the lower eyelid were significantly different, p ≤ 0.0001: temporal = 0.27 ± 0.06, central = 2.14 ± 0.13, and nasal = 3.10 ± 0.15. The temporal third of the lower lid was 14 times as likely as the nasal third to have zero MGYLS; 86% of temporal versus 6% of nasal thirds had zero MGYLS.
Conclusions: This is the first report to document the following: (1) a correlation between the number of MGYLS in the lower eyelid and dry eye symptoms; (2) the number of MGYLS varies significantly across the lower eyelid, with the highest number of MGYLS in the nasal third and the lowest number of MGYLS in the temporal third of the lower eyelid; and (3) instrumentation to standardize diagnostic meibomian gland expression is desirable if not mandatory for the evaluation of meibomian gland function.