Is a thermal pulsation system (LipiFlow) effective as a standalone treatment for meibomian gland dysfunction and dry eye? A systematic review and meta-analysis.

Background: Dry eye disease is a common condition that causes symptoms such as dryness, irritation, and blurry vision. The pathophysiology of dry eye disease features both aqueous deficiency (loss of aqueous tear production) and increased evaporation (loss of the lipid layer), with the latter mechanism responsible for most of the disease presentation. Ocular surface disease (OSD) is a prevalent condition, often linked to meibomian gland dysfunction (MGD), characterized by tear film instability and symptoms like dryness and irritation. Thermal pulsation therapy, an FDA-approved treatment for MGD, uses heat and pressure to restore gland function, improving tear film stability and ocular health. Studies show its benefits last up to a year, enhancing Ocular Surface Disease Index (OSDI), tear break-up time (TBUT), and Meibomian Glands Yielding Secretion Score (MGYSS) scores. This systematic review evaluates LipiFlow compared to placebo, warm compresses, and other devices, focusing on safety, efficacy, and its impact on recovery and long-term outcomes.

Methods: A comprehensive search was performed across PubMed, MEDLINE, Embase, and Scopus until December 2024. Only randomized controlled trials (RCTs) evaluating LipiFlow were included. The primary outcomes assessed were OSDI and TBUT, with secondary outcomes including meibomian gland expression scores, corneal fluorescein staining (CFS), MGYSS, and lipid layer thickness (LLT). Meta-analyses were conducted using a random-effects model, and heterogeneity was assessed using I² statistics.

Results: Thirteen studies reported OSDI (Std diff -0.076, 95% CI -0.277 to 0.125, p = 0.255, I² = 71.21%). Twelve studies evaluated MGYSS, showing significant improvement (Std diff 0.449, 95% CI 0.173-0.725, p = 0.001, I² = 78.49%). TBUT results from twelve studies were not statistically significant (Std diff 0.211, 95% CI -0.017 to 0.440, p = 0.8350, I² = 0%). CFS showed significant improvement in six studies (Std diff -0.130, 95% CI -0.248 to -0.012, p = 0.031, I² = 0%). LLT changes were insignificant (Std diff -0.071, 95% CI -0.381 to 0.239, p = 0.653, I² = 0%).

Conclusion: LipiFlow effectively improves meibomian gland function, as indicated by TBUT, MGYSS, and CFS, but its impact on LLT and OSDI is not significant. The therapy is most beneficial for patients with severe baseline MGD. Further research is needed to establish long-term benefits and patient-specific outcomes.