Effect of Meibomian Gland Expression on Meibomian Gland Regeneration and Function: A Randomized Controlled Trial.

Introduction: This study aims to compare the effect of meibomian gland expression (MGX) combined with lid hygiene versus lid hygiene alone on the meibomian gland's morphology and function for obstructive meibomian gland dysfunction (oMGD). Methods: In this assessor-masked, parallel-group, randomized controlled trial, 64 oMGD patients with mild and moderate meibomian gland (MG) dropout were randomly allocated 1:1 into the MGX and control groups. All participants were informed to do lid hygiene once daily, while the intervention group received MGX every 2 weeks. The primary outcome was the change in MG dropout. Secondary outcomes included the Ocular Surface Disease Index (OSDI), tear stability, MG functions, changes in tear cytokine levels, and safety of MGX in a 12-week follow-up. Results: Sixty-two eyes of sixty-two patients were enrolled in this study. The dropout area of MG decreased significantly in both groups following treatment at all time points. The recovery was faster in the MGX group at 4 weeks (p<0.001). However, no significant difference was observed between the groups after 8 to 12 weeks. Additionally, the MGX group also showed better improvement in OSDI and meibum quality than the control group, while no significant differences were observed between groups for other measures. No adverse events were reported, and the pain level was mild. Conclusion: MGX combined with lid hygiene results in a 13% reduction in MG dropout in the upper and lower eyelids. Moreover, the rate of improvement in MG morphology was faster in patients who underwent additional MGX than in those who performed lid hygiene alone.