title: Comparative study of dual-pulsed 1064 nm Q-switched Nd:YAG laser and single-pulsed 1064 nm Q-switched Nd:YAG laser by using zebrafish model and prospective split-face analysis of facial melasma.
abstract: BACKGROUND
  Recently dual-pulsed low-fluence 1064-nm Q-switched Nd:YAG (QSNY) laser has been developed for reducing complication during melasma treatment.
  
  
  OBJECTIVE
  Comparison of the efficacy and safety between dual-pulsed mode and single-pulsed mode for the treatment of melasma.
  
  
  METHODS
  In preclinical study, adult zebrafish were irradiated with dual-pulsed and single-pulsed mode. Changes of melanophore and cell death were assessed. In split-face clinical study, dual-pulsed and single-pulsed mode were irradiated on the left and right side of the face, respectively. L* value, clinical digital photos, modified Melasma Area and Severity Index (MASI) scores, and side effects were measured.
  
  
  RESULTS
  As compared to single-pulsed mode and dual-pulsed mode with longer intervals, zebrafish melanophore was cleared quickly at dual-pulsed mode with 80-μsec interval and 0.3 J/cm2fluence. Dual-pulsed mode showed the least regeneration of melanophore at 4 weeks after irradiation and no cell death was observed with 80-μsec interval. Both pulse modes improved melasma significantly but modified MASI score and L* value were not significantly different between each other. Lesser pain and shorter duration of post-laser erythema were observed with dual-pulsed mode.
  
  
  CONCLUSIONS
  Dual-pulsed mode was as effective as single-pulsed mode for the treatment of melasma and revealed less side effects.
authors.affiliation: a Department of Dermatology , Arumdaun Nara Dermatologic Clinic , Seoul , Korea.
authors.forename: Hee Won
authors.initials: HW
authors.lastname: Jang
authors.affiliation: b Department of Dermatology, College of Medicine , Korea University Ansan Hospital , Ansan , Korea.
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Chun
authors.affiliation: c Laboratory of Neurodevelopmental Genetics, Graduate School of Medicine , Korea University , Ansan , Korea.
authors.forename: Hae Chul
authors.initials: HC
authors.lastname: Park
authors.affiliation: b Department of Dermatology, College of Medicine , Korea University Ansan Hospital , Ansan , Korea.
authors.forename: Hwa Jung
authors.initials: HJ
authors.lastname: Ryu
authors.affiliation: b Department of Dermatology, College of Medicine , Korea University Ansan Hospital , Ansan , Korea.
authors.forename: Il-Hwan
authors.initials: IH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000535:Aluminum; D000818:Animals; D044466:Asian People; D016923:Cell Death; D005145:Face / Q000528:radiation effects*; D005260:Female; D006801:Humans; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D028022:Low-Level Light Therapy / Q000379:methods*; D008548:Melanosis / Q000532:radiotherapy*; D008875:Middle Aged; D009354:Neodymium; D017060:Patient Satisfaction; D011446:Prospective Studies; D015019:Yttrium; D015027:Zebrafish
chemical_list: C503779:yttrium-aluminum-garnet; D009354:Neodymium; D015019:Yttrium; D000535:Aluminum
keywords: Nd:YAG; melasma; zebrafish