title: Q-switched alexandrite laser treatment of facial and labial lentigines associated with Peutz-Jeghers syndrome.
abstract: BACKGROUND
  The Q-switched alexandrite laser used at 752 nm, a wavelength well absorbed by melanin relative to other optically absorbing structures in skin, causes highly selective destruction of pigment-laden cells. In addition, the 75-nanosecond pulse duration produced by this laser approximates the thermal relaxation time for melanosomes, thereby confining the energy to the target. Facial and labial dark brown macules quickly identify patients with Peutz-Jeghers syndrome. These lentigines may be cosmetically disfiguring. The Q-switched alexandrite laser produces clinically significant fading of mucocutaneous melanosis in association with Peutz-Jeghers syndrome without complications often seen with other therapeutic modalities.
  
  
  OBJECTIVE
  To evaluate the efficacy and safety of the Q-switched alexandrite laser in treating facial and labial lentigines of Peutz-Jeghers syndrome.
  
  
  METHODS
  43 patients diagnosed with Peutz-Jeghers syndrome were treated and studied in our laser center from 2000 to 2010.
  
  
  METHODS
  We used a Q-switched alexandrite laser specified with 75 ns pulse length, emitting at 752 nm and with a 2.4 mm-diameter spot size. The lesional skin was irradiated with fluences of 5-7 J/cm2. The treatment intervals were 3 months.
  
  
  RESULTS
  After treatment with the Q-switched alexandrite laser, 55.8% (24/43) of the patients had excellent results in which more than 75% of the pigments cleared, and 44.2% (19/43) showed good results. Three sessions were required to obtain excellent results. We observed no serious complications.
  
  
  CONCLUSIONS
  We obtain a successful outcome in the treatment of these lentigines with Q-switched alexandrite laser and consider it the treatment of choice for these lesions.
authors.affiliation: Department of Dermatology, Affiliated Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Tong
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Liu
authors.initials: L
authors.lastname: Yang
authors.forename: Juan
authors.initials: J
authors.lastname: Tao
authors.forename: Yating
authors.initials: Y
authors.lastname: Tu
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005145:Face / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D053685:Laser Therapy / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D007834:Lasers; D008297:Male; D010580:Peutz-Jeghers Syndrome / Q000473:pathology / Q000601:surgery*; D012880:Skin Pigmentation