The effect of intense pulsed light on the ocular surface microenvironment of patients with dry eye associated with meibomian gland dysfunction

Purpose: To investigate the effect of IPL on the bacterial flora of the palpebral margin of patients with dry eye disease (DED)-associated meibomian gland dysfunction (MGD). Methods: All subjects were accepted 3 times IPL combined with expression of the meibomian gland (MGX) in the clinic. Cultures were obtained from the margin of the eyelid of the right eyes. Two swabs were taken from each patient at the following time points: Before treatment and the patient completed the first treatment. All swabs were taken for culture and analyzed for bacteria, anaerobic bacteria, and fungi. Tear break-up time (TBUT) was measured before and after 3 weeks of each treatment. Corneal fluorescent staining (CFS), meibomian gland evaluator, lid margin congestion (LMC), and the SPEED questionnaire were evaluated at the beginning and the final follow-up. Results: The bacterial load of the eye lid reduced significantly after IPL treatment. Staphylococcus epidermidiswas the bacterium most frequently isolated and was observed in 55% of all patients before the first treatment with IPL. The CFS, SPEED, and LM score was reduced and the TBUT and MGE score improved after 3-times IPL treatment. Specifically, TBUT improved at every follow-up time. The improvement in the SPEED score and the improvement in the MGE score were correlated with the improvement in TBUT. Conclusions: IPL treatment could reduce the bacterial load of the eyelid margin, improve the TBUT, MGE, and SPEED score. It is a comprehensive treatment for DED as it could improve several OSM factors.