title: Safety and efficacy of erbium-doped yttrium aluminum garnet fractionated laser for treatment of acne scars in type IV to VI skin.
abstract: BACKGROUND
  Ablative resurfacing lasers are effective for treatment of acne scars, but they have a high risk of complications. Fractional lasers have less severe side effects but more moderate efficacy than ablative devices. Studies were performed in individuals with Fitzpatrick skin type I to VI.
  
  
  OBJECTIVE
  To determine the efficacy and safety of an erbium 1,550-nm fractional laser in the treatment of facial acne scars in Fitzpatrick skin types IV to VI.
  
  
  METHODS
  We conducted a prospective, single-blind, randomized trial in patients with acne scars (n=15), skin type IV to VI, with a 1,550-nm erbium fractionated laser. Patients were divided into two groups; one was treated with 10 mJ and the other with 40 mJ. Five monthly laser sessions were performed. A patient questionnaire was distributed.
  
  
  RESULTS
  There was a significant improvement in the acne scarring and overall appearance (p<.001). No significant difference was found between 10 and 40 mJ. Patients were highly satisfied with their results. Significant postinflammatory hyperpigmentation was seen; pain was significantly higher in darker skin.
  
  
  CONCLUSIONS
  Fractional photothermolysis is effective for the treatment of acne scars, but practition-ers should be aware of the higher incidence of pain and postinflammatory hyperpigmentation in individuals with skin types IV to VI.
authors.affiliation: Department of Dermatology, Multicultural Dermatology Center, Henry Ford Hospital, Detroit, Michigan, USA.
authors.forename: Bassel H
authors.initials: BH
authors.lastname: Mahmoud
authors.forename: Divya
authors.initials: D
authors.lastname: Srivastava
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Janiga
authors.forename: James J
authors.initials: JJ
authors.lastname: Yang
authors.forename: Henry W
authors.initials: HW
authors.lastname: Lim
authors.forename: David M
authors.initials: DM
authors.lastname: Ozog
mesh_terms: D000152:Acne Vulgaris / Q000150:complications* / Q000473:pathology / Q000532:radiotherapy; D002921:Cicatrix / Q000209:etiology / Q000473:pathology / Q000601:surgery*; D005145:Face; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D028022:Low-Level Light Therapy / Q000295:instrumentation*; D008297:Male; D017060:Patient Satisfaction; D011446:Prospective Studies; D016037:Single-Blind Method; D012880:Skin Pigmentation; D011795:Surveys and Questionnaires; D016896:Treatment Outcome