An intra-individual quantitative assessment of acute laser injury patterns in facial versus abdominal skin

• Published in: Lasers in surgery and medicine 2011-02, Vol.43 (2), p.99-107
• Main Authors: Bailey, Steven H., Brown, Spencer A., Kim, Yeonsoon, Oni, Georgette, Abtahi, Fatemeh, Richardson, James A., Hoopman, John, Barton, Fritz, Kenkel, Jeffrey M.
• Format: Article
• Language: English
• Subjects: Abdomen; Abdomen - anatomy & histology; Abdomen - pathology; Abdomen - surgery; Adult; Aged; Biopsy; Blood vessels; Carbon dioxide; comparison of human facial and abdominal skin; conversion factor for facial skin; correction factor for facial skin; Cosmetic Techniques; Dermatologic Surgical Procedures; Energy; Face - anatomy & histology; Face - pathology; Face - surgery; factors influencing laser injury; Female; fractional facial resurfacing; Humans; in vivo abdominoplasty model; in vivo pannus model; Injuries; laser resurfacing; Laser Therapy - methods; Lasers; Lasers, Gas - therapeutic use; Male; Mechanical properties; Middle Aged; regional differences in human skin; Rejuvenation; Skin; Skin - anatomy & histology; Skin - pathology; Skin Physiological Phenomena; validation of the in vivo pannus/abdominoplasty laser treatment model
• ISSN: 0196-8092; 1096-9101; 1096-9101
• DOI: 10.1002/lsm.21015

Introduction Clinical laser settings have traditionally been calibrated on abdominal skin to predict and anticipate patterns of injuries in facial skin. This experimental approach has limitations as facial skin and abdominal skin have differences that may influence the depth of laser injury. Objective The primary objective of this study is to analyze the acute pattern of laser injury in abdominal skin and facial skin samples from the same subject and detail the anatomical and biophysical properties that can influence the laser tissue interaction. The secondary objective is to develop a conversion factor that will allow the prediction laser column depths in facial skin based upon laser column depths in abdominal skin. Methods Fifteen healthy subjects were consented and screened. Two 2 mm spots on the face and abdomen were identified and measured and treated with a fractional CO2 laser (Lumenis Ltd, Yokneum, Israel), with an energy setting of 15 mj, 300 Hz at a density of 10. Treatment areas were biopsied and analyzed histologically using hematoxylin and eosin and TUNEL staining. Results Facial skin and abdominal skin have several significant anatomical and biophysical differences (concentration of pilosebaceous units, sebum concentration, and moisture content). Facial tissue demonstrated divergence of laser energy around pilosebaceous units and lateral spread of laser energy along blood vessels. These differences cause attenuation (28%) of the laser energy and result in column depths that are significantly (P