title: Color analysis of nevus of Ota for evaluation of treatment with a Q-switched alexandrite laser.
abstract: OBJECTIVE
  The Q-switched alexandrite laser shows excellent results in treating nevi of Ota. This study sought to examine the utility of color monitoring of the lesion for quantifying the efficacy of laser treatment.
  
  
  METHODS
  Lesion images were obtained from 12 patients using a video microscope before and after a series of laser treatments. The RGB color data in a 50 mm(2) area of the images were converted into coordinates of three color systems and compared with clinical evaluation.
  
  
  RESULTS
  On three coordinates representing the brightness of skin color (the intensity, the L* and the melanin index), there were significant differences between data obtained before and after treatment (P<0.01), in accord with clinical impressions. Darker lesions tended to show more improvement. Coordinates based on chromaticity were less useful for evaluation of treatment.
  
  
  CONCLUSIONS
  Color analysis of nevi of Ota is useful for quantifying efficacy of laser treatment, especially when assessed in a small area of the lesion.
authors.affiliation: Departments of Plastic and Reconstructive SurgeryDermatology, School of Medicine, University of Tokushima, TokushimaDivision of Dermatology, Matsuyama Red Cross Hospital, Ehime, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Miyamoto
authors.affiliation: Departments of Plastic and Reconstructive SurgeryDermatology, School of Medicine, University of Tokushima, TokushimaDivision of Dermatology, Matsuyama Red Cross Hospital, Ehime, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Takiwaki
authors.affiliation: Departments of Plastic and Reconstructive SurgeryDermatology, School of Medicine, University of Tokushima, TokushimaDivision of Dermatology, Matsuyama Red Cross Hospital, Ehime, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yamano
authors.affiliation: Departments of Plastic and Reconstructive SurgeryDermatology, School of Medicine, University of Tokushima, TokushimaDivision of Dermatology, Matsuyama Red Cross Hospital, Ehime, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Ahsan
authors.affiliation: Departments of Plastic and Reconstructive SurgeryDermatology, School of Medicine, University of Tokushima, TokushimaDivision of Dermatology, Matsuyama Red Cross Hospital, Ehime, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Nakanishi
keywords: colorimetry; image analysis; laser treatment; nevus of Ota; video microscope