title: [Determination of the concentration distribution of macular pigment from reflection and fluorescence images].
abstract: OBJECTIVE
  The macular pigment xanthophyll protects the macula in two ways: firstly, it absorbs hazardous blue light and secondly, it acts as a radical scavenger. A low concentration of xanthophyll may be regarded as a risk factor for age-related macular degeneration (AMD). Therefore, we investigated a simple method to determine the xanthophyll concentration at the fundus which is suitable for patient screening.
  
  
  METHODS
  The local distribution of xanthophyll density was determined from monochromatic blue reflection images and autofluorescence images of the fundus in 18 healthy volunteers (mean age: 23.9 years). The significance of the parameters maximal, global, and mean concentration were compared.
  
  
  RESULTS
  The maximal optical density of xanthophyll determined from reflection images was found to be 0.29+/-0.08 (mean for all test persons) which is in good agreement with literature data. The total xanthophyll concentration which is proportional to the maximal density, appeared to be appropriate to describe a person's overall xanthophyll status. Because of the low intensity of autofluorescence images, these are less useful for the determination of the xanthophyll concentration.
  
  
  CONCLUSIONS
  Because of it's simplicity, the determination of xanthophyll concentration as described here can be performed by every ophthalmologist using a fundus camera and is, therefore, suitable as a screening method.
authors.affiliation: Augenklinik, FSU, Jena. martin.hammer@med.uni-jena.de
authors.forename: M
authors.initials: M
authors.lastname: Hammer
authors.forename: D
authors.initials: D
authors.lastname: Schweitzer
authors.forename: L
authors.initials: L
authors.lastname: Leistritz
mesh_terms: D000293:Adolescent; D005260:Female; D005451:Fluorescein Angiography; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008266:Macula Lutea / Q000473:pathology*; D008268:Macular Degeneration / Q000175:diagnosis / Q000517:prevention & control; D008297:Male; D008403:Mass Screening; D009887:Ophthalmoscopy; D012016:Reference Values; D012307:Risk Factors; D024341:Xanthophylls / Q000378:metabolism*
chemical_list: D024341:Xanthophylls
vernacular_title: Bestimmung der Konzentrationsverteilung des Makulapigmentes aus Reflexions- und Fluoreszenzaufnahmen.