title: Superficial wounding model for epidermal barrier repair studies: comparison of Erbium:YAG laser and the suction blister method.
abstract: OBJECTIVE
  Wound-healing studies use mainly mechanical methods for wound induction, which are laborious and difficult to standardize. Objective of this study was to evaluate the Erbium:Yttrium-Aluminium-Garnet (Er:YAG) laser method as a model of epidermis ablation on human skin in vivo and to compare the quality and healing rates of Er:YAG laser and suction blister (SB) wounds.
  
  
  METHODS
  Er:YAG laser and SB wounds were made on the forearms of 10 healthy volunteers. Post-wounding measurements including wound surface area (WSA) from photographs, wound depth from 3D volume analysis, trans-epidermal water loss (TEWL), laser doppler blood flow (LDBF), and optical coherence tomography (OCT) imaging were made daily over 7 days. Biopsies were taken on Days 4 and 7.
  
  
  RESULTS
  3D analysis showed laser wounds to be shallower and more uniform in depth than SB: 54 ± 14 µm versus 140 ± 102 µm, respectively, with histology demonstrating complete epidermal removal using SB. SB wounds were more variable in size with a WSA of 0.47 ± 0.24 cm(2) compared to 1.17 ± 0.14 cm(2) for laser wounds. Healing rates were similar in both groups, as measured by TEWL, LDBF, and WSA. OCT imaging on Days 3-4 revealed new epidermis below the fibrin clot, similar to histology, and a visible stratum corneum on Day 7, but no apparent epidermal hyperplasia in contrast to histology.
  
  
  CONCLUSIONS
  Compared to the SB model, Er:YAG laser achieved rapid standardized epidermal ablation, which despite morphological differences, was similar in terms of epidermal regeneration/barrier formation.
authors.affiliation: Skin Research Centre, Pierre Fabre Dermocosmétique, Hotel Dieu, Toulouse, France.
authors.forename: Younes
authors.initials: Y
authors.lastname: Ferraq
authors.forename: David R
authors.initials: DR
authors.lastname: Black
authors.forename: Jennifer
authors.initials: J
authors.lastname: Theunis
authors.forename: Serge
authors.initials: S
authors.lastname: Mordon
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001706:Biopsy; D001768:Blister / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D004817:Epidermis / Q000293:injuries / Q000473:pathology / Q000502:physiology; D006801:Humans; D017078:Laser-Doppler Flowmetry; D053844:Lasers, Solid-State; D008297:Male; D010865:Pilot Projects; D012867:Skin / Q000098:blood supply / Q000293:injuries* / Q000473:pathology; D012879:Skin Physiological Phenomena; D013396:Suction; D041623:Tomography, Optical Coherence; D014870:Water Loss, Insensible; D014945:Wound Healing / Q000502:physiology*; D055815:Young Adult