Abstract
PURPOSE: Meibomian gland dysfunction (MGD) is a common clinical problem that is often associated with evaporative dry eye disease. Alterations of the lipids of the meibomian glands have been identified in several studies of MGD. This prospective, observational, open-label clinical trial documents the improvement in both clinical signs and symptoms of disease and spectroscopic behavior of the meibomian gland lipids after therapy with topical azithromycin ophthalmic solution. METHODS: Subjects with symptomatic MGD were recruited. Signs of MGD were evaluated with a slit lamp. Symptoms of MGD were measured by the response of subjects to a questionnaire. Meibum lipid, lipid-lipid interaction strength, and conformation and phase transition parameters were measured using Fourier transform infrared spectroscopy. RESULTS: In subjects with clinical evidence of MGD, changes in ordering of the lipids and resultant alteration of phase transition temperature were identified. Topical therapy with azithromycin relieved signs and symptoms and restored the lipid properties of the meibomian gland secretion toward normal. CONCLUSIONS: Improvement in phase transition temperature of the meibomian gland lipid with the determined percent trans rotomer composition of the lipid strongly suggests that the ordering of the lipid molecules is altered in the disease state (MGD) and that azithromycin can improve that abnormal condition toward normal in a manner that correlates with clinical response to therapy.