title: 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
  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.
  
  
  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.
authors.affiliation: 1 Medical Light Consulting , Heidelberg, Germany .
authors.forename: Alexander
authors.initials: A
authors.lastname: Wunsch
authors.forename: Karsten
authors.initials: K
authors.lastname: Matuschka
mesh_terms: D000328:Adult; D000368:Aged; D003094:Collagen / Q000378:metabolism; D003357:Cosmetic Techniques; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007259:Infrared Rays / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D011446:Prospective Studies; D012867:Skin / Q000000981:diagnostic imaging / Q000378:metabolism / Q000528:radiation effects*; D015595:Skin Aging; D014463:Ultrasonography
chemical_list: D003094:Collagen