Assessment of the mobile delivery of infrared light (1100-1800 nm) for the treatment of facial and neck skin laxity.

BACKGROUND: Previous studies have shown that although infrared light and radiofrequency delivered by stationary application is safe and effective for the treatment of rhytides, a mobile delivery of radiofrequency energy can render the treatment as painless. In addition, few studies have defined and assessed efficacy of these infrared treatments in treating laxity by quantitative grading.

OBJECTIVE: This prospective study assesses the safety, efficacy, and pain profile of the application of infrared light with a mobile delivery method for the treatment of facial and neck skin laxity as assessed by a tested, quantitative grading scale.

METHODS: In this study, 22 female subjects (aged 40-75 years; Caucasian and Asian ancestry) with a clinically observable excess of laxity (minimum grade 2 out of 4) on the face received 1 to 3 treatments with incoherent infrared (1100-1800 nm) light at 2-week to 4-week intervals. Each light pulse was administered in a mobile continuous fashion within a localized area measuring approximately 1 handpiece tip-width laterally and vertically. A series of 4 to 5 pulses were administered across small grid areas, followed by 6 to 8 passes to each grid area, totaling approximately 300 to 450 pulses per treatment. Each mobile pulse was delivered at fluences of 45 to 46 J/cm2 to the face, 45 J/cm2 to the mandible, and 44 J/cm2 to the neck. Clinical results were evaluated employing a comprehensive 4-point grading scale from photographs at baseline, and the 1-month and 3-month follow-up visits after the final treatment. Pain ratings were evaluated by visual analog scale (VAS) gradings and patient questionnaire immediately following treatment.

RESULTS: All subjects completed and responded to treatment. The mean treatment number was 2.1 (+/- 0.9) and the mean follow-up interval was 1.9 (+/- 1) months. The quantitative evaluations demonstrated: a mean baseline laxity grade of 2.9 +/- 0.5 and mean posttreatment laxity grade of 2.5 +/- 0.6; and a mean difference in prelaxity grades versus postlaxity grades of 0.4 +/- 0.3 (95% CI; 0.2540-0.5415). The data demonstrated a statistically significant difference between before and after measurements (P<.0001) and a mean percent improvement in laxity grading scores of 14.1 +/- 11.3%. The treatment discomfort was rated as a mean of 0.7 (+/- 0.6) on a VAS grading scale (0 to 10). By patient questionnaire, sensation during the treatment was rated as painless by 100% of patients and rare (<5) transient moments of heat-related pain sensation were reported by 18% of patients. None of patients reported the procedure as painful or as sensing frequent (>5) or persistent heat-related pain sensation during the treatment. Other side effects included minimal erythema which resolved within 1 to 3 hours. No crusting, dyspigmentation, or scarring was observed.

CONCLUSION: This prospective clinical study with quantitative grading of laxity and VAS pain scores demonstrated that mobile delivery of infrared light appears to be safe, clinically effective, and painless in reducing facial and neck laxity. The mobile infrared light delivery allowed for delivery of approximately 30% higher fluence dosages and increased passes to each pulse area. The clinically observable and quantified decreases in skin laxity following treatment were statistically significant.