Effect of low-level light therapy versus intense pulsed light on subjective and objective dry eye parameters

Purpose To evaluate and compare the therapeutic effectiveness of low-level light therapy (LLLT) and intense pulsed light (IPL) in the management of dry eye disease (DED), utilizing both subjective symptom scores and objective clinical outcomes. Patients and methods This retrospective study included 60 eyes from 60 patients with meibomian gland disease-related DED, divided into two equal groups (30 eyes each). All patients underwent four treatment sessions at a 1-week interval. Each of the lipid layer thickness, noninvasive tear breakup time, tear meniscus height, and Dry Eye Questionnaire-5 scores was assessed at baseline and 3 months after the final session. Results Both LLLT and IPL groups showed significant within-group improvements after treatment. However, post-treatment comparisons demonstrated superior outcomes for LLLT regarding the lipid layer thickness (87.6 vs. 71.2, P <0.001), tear meniscus height (0.25 vs. 0.17, P <0.001), and Dry Eye Questionnaire-5 (3.9 vs. 4.9, P <0.001). Delta change analysis confirmed the aforementioned results. Conclusion Both LLLT and IPL therapies yielded significant improvements in clinical parameters and patient-reported outcomes in meibomian gland disease-related DED; however, LLLT demonstrated superior efficacy in enhancing tear film stability and alleviating symptoms, supporting its possible consideration as a more effective therapeutic modality.