title: Non-ablative fractional laser provides long-term improvement of mature burn scars--a randomized controlled trial with histological assessment.
abstract: OBJECTIVE
  Non-ablative fractional laser-treatment is evolving for burn scars. The objective of this study was to evaluate clinical and histological long-term outcome of 1,540 nm fractional Erbium: Glass laser, targeting superficial, and deep components of mature burn scars.
  
  
  METHODS
  Side-by-side scar-areas were randomized to untreated control or three monthly non-ablative fractional laser-treatments using superficial and extra-deep handpieces. Patient follow-up were at 1, 3, and 6 months. Primary outcome was improvement in overall scar-appearance on a modified-Patient-and-Observer-Scar-Assessment-Scale (mPOSAS, 1 = "normal skin", 10 = "worst imaginable scar"). Secondary outcomes included histology, patient satisfaction (0-10), patient-assessed improvement, and safety.
  
  
  RESULTS
  Study was completed by 17 of 20 randomized patients with normotrophic (n = 11), hypertrophic (n = 5) or atrophic (n = 1) scars. Scar-appearance improved from laser-treatments (P < 0.001 vs. untreated) and histology at 6 months supported collagen-remodeling. Improvement appeared continuously during the post-operative period (mPOSAS baseline: 7 [5-8], 6 months: 4 [3-5] P = < 0.001). At 6 months, patients were satisfied with treatment (6 [3-9]) and 82% reported improved scar-texture. Treatments caused mild to moderate pain (4 [2-7]). Adverse effects decreased during follow-up and at final assessment, discrete erythema, hyperpigmentation or imprints from laser-grid were present in 11 patients. No patients experienced worsening of scar-appearance.
  
  
  CONCLUSIONS
  Combined superficial and deep non-ablative fractional laser-treatments induce long-term clinical and histological improvement of mature burn scars.
authors.affiliation: Department of Dermatology, Bispebjerg Hospital, University of Copenhagen, Denmark.
authors.forename: Elisabeth H
authors.initials: EH
authors.lastname: Taudorf
authors.forename: Patricia L
authors.initials: PL
authors.lastname: Danielsen
authors.forename: Ida F
authors.initials: IF
authors.lastname: Paulsen
authors.forename: Katrine
authors.initials: K
authors.lastname: Togsverd-Bo
authors.forename: Christine
authors.initials: C
authors.lastname: Dierickx
authors.forename: Uwe
authors.initials: U
authors.lastname: Paasch
authors.forename: Merete
authors.initials: M
authors.lastname: Haedersdal
mesh_terms: D000328:Adult; D002056:Burns / Q000150:complications* / Q000473:pathology; D002921:Cicatrix / Q000209:etiology / Q000473:pathology / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053685:Laser Therapy; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D017060:Patient Satisfaction; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
keywords: burns; cosmetic surgery; laser treatment; non-ablative Erbium: glass laser; photothermolysis; scar texture; skin grafts