title: Inflammatory Acne in the Asian Skin Type III Treated with a Square Pulse, Time Resolved Spectral Distribution IPL System: A Preliminary Study.
abstract: OBJECTIVE
  Acne remains a severe problem for both patients and clinicians. Various approaches using photosurgery and phototherapy have been reported with varying degrees of success and robustness of results. An improved intense pulsed light (IPL) system has become available with interesting beam characteristic which might improve IPL treatment of inflammatory acne in the Asian skin, Fitzpatrick type III/IV.
  
  
  METHODS
  The 18 study subjects comprised 15 females and 3 males with active mild to moderately severe inflammatory acne (mean age 25.3 ± 7.70 yr, range 17-47 yr, Burton scale 1-4, all Fitzpatrick type III Asian skin). They were treated once (8 subjects) or twice (10 subjects) with an IPL system offering both square pulse and time resolved spectral distribution technologies (420 nm cut-off filter, 30 ms pulse, 8 - 12 J/cm(2), 2-3 passes). Clinical photography was taken at baseline and at 4 weeks after the final treatment. Percentage of acne clearance was assessed by an independent dermatological panel and graded from zero to 5, 5 being total clearance.
  
  
  RESULTS
  All subjects completed the study. Post-treatment side effects were mild and transient, with virtually no downtime or postinflammatory hyperpigmentation (PIH) experienced by any subject. All subjects had some improvement and no exacerbation was seen in any subject. Clearance was evaluated by the panel as grade 4 in 5 subjects, grade 3 in 8, grade 2 in 4 and grade 1 in 1, so that 14 of 18 subjects (78%) had clearance of at least 60%. Patient evaluation was in general slightly better than that of the panel.
  
  
  CONCLUSIONS
  The special beam characteristics of the IPL system used in the present preliminary study achieved good to very good results in the treatment of acne in the Fitzpatrick type III Asian skin without PIH induction. The results suggested that acne treatment in the Asian skin using this system is both safe and effective, and merits larger population studies to further optimize parameters and standardize top-up treatments.
authors.affiliation: Drs Woo & Hann's Skin & Laser Clinic, Seoul, South Korea.
authors.forename: Geun-Soo
authors.initials: GS
authors.lastname: Lee
keywords: Acne vulgaris; Fitzpatrick Asian skin type III; endogenous PDT; square pulse; time resolved spectral distribution