title: Periorbital hyperpigmentation in Asians: an epidemiologic study and a proposed classification.
abstract: BACKGROUND
  Periorbital hyperpigmentation (POH) presents with a dark area surrounding the eyelids. It is an ill-defined condition, and the pathogenesis can be multifactorial.
  
  
  OBJECTIVE
  This epidemiologic study was conducted to assess the prevalence of periorbital hyperpigmentation in Singapore in an attempt to propose a classification.
  
  
  METHODS
  One thousand consecutive patients attending the general dermatology clinic at the National Skin Center were enrolled in the study to assess for POH, of whom 200 with POH were examined and investigated to define the cause of POH. The possible causes were determined according to a detailed history, clinical examination, and assessment by three dermatologists. The extent of the POH was measured using a mexameter.
  
  
  RESULTS
  The commonest form of POH was the vascular type (41.8%), followed by constitutional (38.6%), postinflammatory hyperpigmentation (12%), and shadow effects (11.4%). The vascular type was seen predominantly in Chinese, whereas as the constitutional type was most common in Indians and Malays.
  
  
  CONCLUSIONS
  The vascular form of POH was the predominant type. We propose a comprehensive classification for POH that we hope will influence the choice of treatment modalities used in managing POH in the future.
authors.affiliation: National Skin Center, Singapore. harneet.ranu@gmail.com
authors.forename: Harneet
authors.initials: H
authors.lastname: Ranu
authors.forename: Steven
authors.initials: S
authors.lastname: Thng
authors.forename: Boon Kee
authors.initials: BK
authors.lastname: Goh
authors.forename: Allan
authors.initials: A
authors.lastname: Burger
authors.forename: Chee Leok
authors.initials: CL
authors.lastname: Goh
mesh_terms: D000293:Adolescent; D000328:Adult; D044466:Asian People; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D017495:Hyperpigmentation / Q000145:classification* / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D009916:Orbital Diseases / Q000145:classification* / Q000453:epidemiology*; D012846:Singapore / Q000453:epidemiology; D011795:Surveys and Questionnaires