A Controlled Trial to Determine the Efficacy of Red and Near-Infrared Light Treatment in Patient Satisfaction, Reduction of Fine Lines, Wrinkles, Skin Roughness, and Intradermal Collagen Density Increase

Abstract

Objective: The purpose of this study was to investigate the safety and efficacy of two novel light sources for large area and full body application, providing polychromatic, non-thermal photobiomodulation (PBM) for improving skin feeling and appearance. Background data: For non-thermal photorejuvenation, laser and LED light sources have been demonstrated to be safe and effective. However, lasers and LEDs may offer some disadvantages because of dot-shaped (punctiform) emission characteristics and their narrow spectral bandwidths. Because the action spectra for tissue regeneration and repair consist of more than one wavelength, we investigated if it is favorable to apply a polychromatic spectrum covering a broader spectral region for skin rejuvenation and repair. Materials and methods: A total of 136 volunteers participated in this prospective, randomized, and controlled study. Of these volunteers, 113 subjects randomly assigned into four treatment groups were treated twice a week with either 611-650 or 570-850 nm polychromatic light (normalized to *9 J/cm 2 in the range of 611-650 nm) and were compared with controls (n = 23). Irradiances and treatment durations varied in all treatment groups. The data collected at baseline and after 30 sessions included blinded evaluations of clinical photography, ultrasonographic collagen density measurements, computerized digital profilometry, and an assessment of patient satisfaction. Results: The treated subjects experienced significantly improved skin complexion and skin feeling, profilometrically assessed skin roughness, and ultrasonographically measured collagen density. The blinded clinical evaluation of photographs confirmed significant improvement in the intervention groups compared with the control. Conclusions: Broadband polychromatic PBM showed no advantage over the red-light-only spectrum. However, both novel light sources that have not been previously used for PBM have demonstrated efficacy and safety for skin rejuvenation and intradermal collagen increase when compared with controls.

Infrared and skin: Friend or foe

“…In a study, the differences between poly- (570-850nm, 42.8-54.8 mW/cm2, 49.3-51.4 J/cm2) vs mono- (630 nm, 5.9-23.4 mW/cm2, 15.5-16.6 J/cm2) chromatic light treatments in clinical outcome and patient satisfaction were not significant, indicating that despite spectral differences, both light sources were commensurably effective in the study objectives to reduce aging skin [41]. …”

Safety, efficacy, and usage compliance of home‐use device utilizing RF and light energies for treating periorbital wrinkles

“…Wunsch et al . demonstrated the effect of broadband polychromatic light energy on wrinkle status in 113 subjects, as assessed by a blinded evaluation of three reviewers. Responders’ analysis has shown an improvement in wrinkle status in 69–75% of the treated subjects (depending on the wavelength range used for treatment).…”

“…Red LEDs specifically have been shown to induce dermal changes such as activating the growth of fibroblast cells, increasing collagen synthesis, and inducing enzymatic activities in the subcutaneous layer of the skin. These effects in turn influence the skin appearance and are correlated with a more vibrant and firm skin texture …”

Assessment of Laser Effects on Skin Rejuvenation

“…49 The PBM technique without thermal reactions has been able to dramatically increase patients' satisfaction with skin rejuvenation. 50 Laser Effects on Tissues Laser-skin interaction can be categorized as: photochemical, photothermal and photoplasmal pheromones. Photochemical reactions happen when the energy of photons made by the laser in the molecules of the cells causes chemical reactions in the molecules without changes in temperature.…”