Effect of Intense Pulsed Light Therapy in Dry Eye Disease Caused by Meibomian Gland Dysfunction: A Systematic Review and Meta-Analysis

Background: This study aimed to systematically evaluate the effect of intense pulsed light (IPL) therapy in patients harboring dry eye disease caused by meibomian gland dysfunction (MGD) based on qualified studies. Methods: The electronic databases, including PubMed, Cochrane, and Embase, were searched using keywords to identify available publications updated to November 2021. Relative risk or weighted mean difference combined with 95% confidence interval was used to synthesize the outcomes of included studies. The meta-analysis included 15 randomized controlled trials with 1,142 patients (2,284 eyes). Results: The results revealed that IPL could significantly decrease the ocular surface disease index (OSDI), standard patient evaluation of eye dryness (SPEED), artificial tear usage, tear film lipid layer, meibomian gland quality (MGQ), meibomian gland expression (MGX), and corneal fluorescein staining (CFS) while increase tear break-up time (TBUT) and noninvasive tear break-up time (NIBUT) compared with sham. Compared with MGX, IPL+MGX markedly decreased the SPEED, CFS, and tear meniscus height (TMH), but with increased TBUT. Compared with MGX, IPL showed significant effect in increasing the OSDI and TBUT, but decreasing the TMH and NIBUT. However, no significant differences were seen between IP+MGX and MGX in OSDI, MGQ, and MGX, nor between IPL and MGX in OSDI, SPEED, and TBUT. Conclusion: We identified that the application of IPL alone or IPL combined with MGX elicited superior clinical effect for improving the eye function and symptoms in the treatment of MGD-related dry eye disease, which is considered available for wide clinical application.