USB-powered vs. self-heating warm compresses for meibomian gland dysfunction: A prospective randomized crossover clinical trial

Background Dry eye syndrome (DES) is a prevalent multifactorial condition characterized by tear film instability and meibomian gland dysfunction (MGD). Warm compress therapy remains a cornerstone for improving lipid layer function. However, very limited comparative data exist on newer USB-powered devices vs. self-heating masks in Middle Eastern populations. Methods This randomized crossover clinical trial compared USB-powered and self-heating masks in 15 participants aged 18–40 years with meibomian gland dysfunction (MGD) associated eye (tear break-up time ≤10 s). Each intervention was scheduled for five consecutive days, separated by a two-week washout. The prespecified primary outcome was non-invasive TBUT measured with the OCULUS Keratograph 4M; tear meniscus height (TMH) and symptom scores were secondary outcomes. A two-way ANOVA and Post-hoc Bonferroni tests adjusted for multiple comparisons were used for analysis. The trial was registered at ClinicalTrials.gov (NCT07618169). Results All 15 participants contributed data to both intervention phases. Across observed visits, the USB-powered device was associated with higher TBUT (likelihood-ratio χ 2 (1) = 7.43, p = 0.006) and TMH (χ 2 (1) = 4.49, p = 0.034). Day 5 descriptive means with USB-Powered compress and self-heating mask were 9.53 ± 2.18 s versus 7.21 ± 2.90 s for TBUT, and 0.200 ± 0.020 mm versus 0.188 ± 0.016 mm for TMH, respectively. No significant between-device difference was observed in SPEED scores, although mean scores showed a mild improvement, and no adverse events were reported. Conclusions USB-powered warm compresses provided superior outcomes in enhancing tear film stability and volume compared to self-heating masks. Consistent temperature control and reusability make them a promising at-home therapy for patients with MGD. USB-powered devices may be preferred for patients requiring sustained thermal therapy, particularly in arid climates with variable indoor cooling. Further large-scale trials are warranted to confirm these findings. Clinical Trial Registration This trial was registered at ClinicalTrials.gov under registration number: NCT07618169 .