Abstract
BACKGROUND: We developed and tested the safety and efficacy of a cosmetic device to improve dark circles using electrical muscle stimulation of the orbicularis oculi muscle. METHODS: Overall, 18 participants (36 eyes) were studied. The following five items were evaluated before and after the intervention:(1) the Clinical Dark Circle Score using clinical findings and photographs, (2) transcutaneous oxygen partial pressure (TcPO(2)) on the lower eyelid, (3) thermography, (4) two-dimensional laser blood flowmetry, and (5) spectrophotometry. RESULTS: The mean score at baseline was 2.0 ± 0.90 (mean ± standard deviation), and that at the end of the study was 1.2 ± 1.0 (Wilcoxon signed-rank sum test, p < 0.0001), indicating a significant reduction. The spectrophotometer showed a significant decrease in a* and L* values before and after use (Wilcoxon signed-rank sum test, p < 0.0001). There was also a weak negative correlation between the change in score and the change in blood flow and TcPO(2) measured using a laser perfusion device (Spearman's rank correlation coefficient, r = -0.32 and -0.39, respectively). Stratified analysis of the baseline score showed a strong negative correlation between the change in score and the change in spectrophotometric a* in the subjects/group with mild periocular dark circles (Spearman's rank correlation coefficient, r = -0.46). Contrastingly, no correlation was observed for any of the measurements in the subjects/group with severe periocular dark circles. After 1 month, no device-related ophthalmic adverse events were observed in any of the participants. CONCLUSION: Electrical muscle stimulation could improve periocular dark circles, especially in the subjects/group with mild periocular dark circles, and was safe.