title: A continuously variable beam-diameter, high-fluence, Q-switched Nd:YAG laser for tattoo removal: comparison of the maximum beam diameter to a standard 4-mm-diameter treatment beam.
abstract: BACKGROUND
  Laser beam diameter affects the depth of laser penetration. Q-switched lasers tend to have smaller maximum spot sizes than other dermatologic lasers, making beam diameter a potentially more significant factor in treatment outcomes.
  
  
  OBJECTIVE
  To compare the clinical effect of using the maximum-size treatment beam available for each delivered fluence during laser tattoo removal to a standard 4-mm-diameter treatment beam.
  
  
  METHODS
  Thirteen tattoos were treated in 12 subjects using a Q-switched Nd:YAG laser equipped with a treatment beam diameter that was adjustable in 1 mm increments and a setting that would enable the maximally achievable diameter ("MAX-ON" setting) with any fluence. Tattoos were randomly bisected and treated on one side with the MAX-ON setting and on the contralateral side with a standard 4-mm-diameter spot ("MAX-OFF" setting). Photographs were taken 8 weeks following each treatment and each half-tattoo was evaluated for clearance on a 10-point scale by physicians blinded to the treatment conditions.
  
  
  RESULTS
  Tattoo clearance was greater on the side treated with the MAX-ON setting in a statistically significant manner following the 1st through 4th treatments, with the MAX-OFF treatment site approaching the clearance of the MAX-ON treatment site after the 5th and 6th treatments.
  
  
  CONCLUSIONS
  This high-energy, Q-switched Nd:YAG laser with a continuously variable spot-size safely and effectively removes tattoos, with greater removal when using a larger spot-size.
authors.affiliation: Main Line Center for Laser Surgery, 32 Parking Plaza, Suite 200, Ardmore, Pennsylvania, 19003.
authors.forename: Eric F
authors.initials: EF
authors.lastname: Bernstein
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Civiok
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D053844:Lasers, Solid-State / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000175:diagnosis / Q000209:etiology; D010147:Pain Measurement; D010781:Photography; D016037:Single-Blind Method; D013653:Tattooing; D016896:Treatment Outcome
keywords: KTP; Nd:YAG; laser; removal; tattoo