Low-level light therapy and intense pulse light therapy in meibomian gland dysfunction. A systematic review and meta-analysis

Meibomian gland dysfunction (MGD) is a leading cause of dry eye disease, affecting over a third of the global population. This disease is associated with ocular discomfort, reduced visual quality, and quality of life. Novel treatments like Intense Pulse Light (IPL) therapy and Low-Level Light Therapy (LLLT) have been reported to be useful in refractory MGD treatment. However, no systematic review has explored the utility of combining these two therapies.

Medline, Embase, and CENTRAL databases were searched for articles on LLLT + IPL therapy in MGD. A meta-analysis of single means was conducted to assess clinical endpoints.

Analysis of 12 studies showed that LLLT + IPL therapy in MGD patients led to a significant decrease in Ocular Surface Disease Index score (MD: −22.8, 95 %CI: −29.1 to −16.5, I² = 97.5 %, p < 0.001), and a significant increase in both Tear Break-up Time (MD: 2.2 s, 95 %CI: 0.9 s to 3.4 s, I² = 98.6 %, p < 0.001) and Schirmer test (MD: 1.5 mm, 95 %CI: 0.6 mm to 2.5 mm, I² = 0.0 %, p = 0.001) at ≤ 3 months post treatment. These improvements were sustained in a sensitivity analysis at endpoints ≥ 6 months post treatment. While the percentage of loss of meibomian gland area (n = 4, MD: −3.8 %, 95 %CI: −7.2 % to −0.4 %, I² = 40.0 %, p = 0.031) was reported to be significantly reduced, this was not found to be sustained at endpoints ≥ 6 months post treatment (n = 2, MD: 5.9 %, 95 %CI: 1.8 % to 10.0 %, I² = 0.0 %, p = 0.005) in two studies.

This meta-analysis provides quantitative evidence supporting the clinical efficacy of LLLT + IPL therapy in MGD. Future research should evaluate its long-term safety and efficacy and compare it with alternative treatments.