Comparison of Light-Based Devices in the Treatment of Meibomian Gland Dysfunction.

Purpose: To compare different light-based devices, namely, intense pulsed light (IPL) and IPL with low-level light therapy (LLLT), in the treatment of meibomian gland dysfunction (MGD).Methods: This was a prospective, observational study that included patients with MGD. Group 1 included 58 eyes treated with IPL (eye-light (R), Espansione Marketing S.p.A., Bologna, Italy), followed by LLLT (my mask (R), Espansione Marketing S.p.A., Bologna, Italy); Group 2 included 60 eyes treated with IPL (E>Eye (R), E-Swin, Houdan, France); and Group 3 included 58 eyes treated with IPL (Thermaeye Plus (R), OptiMed, Sydney, Australia). The presence of symptoms (Ocular Surface Disease Index (OSDI)) and ocular surface changes were evaluated at baseline, three weeks, and six months after treatment.Results: At week three, there was an improvement in the OSDI in all groups (p<0.001), without differences among them (p=0.339). The lipid layer thickness (LLT) increased in Groups 1 and 2 (p<0.001), with a similar variation (p=0.144). Patients with superior OSDI and lower LLT at baseline had the greatest improvement in the respective parameters (p<0.001). The basal tear flow increased in Group 1 (p=0.012). Corneal staining (CS) significantly decreased in Groups 2 (p<0.001) and 3 (p<0.001). At six months, compared to three weeks, there was further improvement in the OSDI (p<0.001) and the LLT (p=0.007), in Group 1, and an increase in the presence of CS in Group 3 (p=0.011).Conclusion: IPL treatment led to a sustained decrease in patients' symptoms, even after six months. Different IPL devices seem to have different beneficial effects. Adding LLLT to IPL appears to have an additional long-term beneficial effect as well as positive effects on the lacrimal gland.