title: The dual toning technique for melasma treatment with the 1064 nm Nd: YAG laser: A preliminary study.
abstract: OBJECTIVE
  Melasma is a treatment-resistant and acquired pigmentary facial skin condition of uncertain etiology particularly prevalent in the older Asian female. Traditional bleaching agents have offered some success. Intense pulsed light (IPL), fractionated nonablative and more recently ablative laser technology have also been used, but were associated with postoperative hyperpigmentation in the Asian skin. The present study examined the consecutive application of 2 modes of the 1064 nm Nd:YAG laser in the 'dual toning' process.
  
  
  METHODS
  Thirty females, mean age 41.4 ± 11.96 yr, Fitzpatrick skin type IV, participated in the prospective uncontrolled study. All subjects were treated with the 1064 nm Nd:YAG laser, first with the 5 ns Q-switched mode, 1.2 J/cm(2), 8 mm collimated handpiece with multiple passes and then immediately after with the micropulsed mode, 300 µs, 7.0 J/cm(2), 5 mm handpiece, multiple passes. Mild and even erythema was the endpoint. Treatments were given every other week until maximum improvement was obtained. Improvement was rated at a final assessment 6 weeks after the final treatment on a 5 point scale where 1 was little or no improvement and 5 was maximum improvement.
  
  
  RESULTS
  At the final treatment session and at the 6-week assessment, 20 of the 30 patients (67%) saw a fair to excellent degree of improvement, 7 (23%) had visible improvement and little or no improvement was seen in 3 (10%) patients. There were no unexpected side effects in any patients.
  
  
  CONCLUSIONS
  The dual toning technique using the 1064 nm Nd:YAG laser was safe and effective, and well-tolerated by all patents without anesthesia. Larger controlled studies are merited with more objective measurement techniques to confirm the results of this preliminary study.
authors.affiliation: Department of Dermatology, Ajou University School of Medicine, Suwon, Korea.
authors.forename: Hy
authors.initials: H
authors.lastname: Kang
authors.forename: Jh
authors.initials: J
authors.lastname: Kim
authors.forename: Bc
authors.initials: B
authors.lastname: Goo
keywords: Micropulsed laser; Q-switched laser; pulse stacking; subcellular selective photothermolysis