title: Effect of pulse width of a 595-nm flashlamp-pumped pulsed dye laser on the treatment response of keloidal and hypertrophic sternotomy scars.
abstract: BACKGROUND
  Flashlamp-pumped pulsed dye lasers (PDLs) have successfully treated keloidal and hypertrophic scars.
  
  
  OBJECTIVE
  The objective was to investigate the effect of pulse width of a PDL in treating keloidal and hypertrophic scars.
  
  
  METHODS
  On each of 19 patients, keloidal or hypertrophic median sternotomy scars were divided into two segments. Both segments on all patients were randomly treated with a 595-nm PDL at a fluence of 7 J/cm(2) and pulse widths of 0.45 and 40 ms to both segments, every 4 weeks for a total of three treatments. Scar volume, height, erythema, and pliability were measured at Weeks 0, 4, 8, and 24.
  
  
  RESULTS
  The volume of segments treated with 0.45- and 40-ms pulses decreased significantly after two treatments. Segments treated with a 0.45-ms pulse width showed significantly greater improvement than those treated with 40-ms pulses after three treatments. Elasticity of 0.45-ms segments was significantly higher than those of 40-ms segments, following two treatments. Pulse width had no significant effect in improvement of scar erythema.
  
  
  CONCLUSIONS
  A pulse width of 0.45 ms of PDL was more effective in decreasing scar size and improving scar pliability than that of 40 ms. A 595-nm PDL was safe and effective in treatment of hypertrophic scars and keloids in dark-skinned individuals. This study was supported in part by an educational grant from the Dermatological Society of Thailand.
authors.affiliation: Department of Dermatology, Siriraj Hospital, Mahidol University, Bangkok, Thailand. siwmn@mahidol.ac.th
authors.forename: Woraphong
authors.initials: W
authors.lastname: Manuskiatti
authors.forename: Rungsima
authors.initials: R
authors.lastname: Wanitphakdeedecha
authors.forename: Richard E
authors.initials: RE
authors.lastname: Fitzpatrick
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D017439:Cicatrix, Hypertrophic / Q000628:therapy*; D005260:Female; D006801:Humans; D007627:Keloid / Q000628:therapy*; D028022:Low-Level Light Therapy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018709:Statistics, Nonparametric; D013249:Sternum / Q000601:surgery*; D013908:Thoracotomy; D016896:Treatment Outcome; D014945:Wound Healing