title: The use of heterochromatic flicker photometry to determine macular pigment optical density in a healthy Australian population.
abstract: OBJECTIVE
  To establish the normal macular pigment density (MPOD) in a healthy adult Australian sample using heterochromatic flicker photometry (HFP).
  
  
  METHODS
  Macular pigment density was measured using heterochromatic flicker photometry in a total of 201 subjects ranging in age from 21 to 84 years with healthy macula. Fifty-seven of the healthy subjects also completed a food-frequency dietary questionnaire. Best-corrected visual acuity (BCVA) was measured using logMAR, chart and macular morphological profiles were assessed using high-resolution integrated Fourier-domain optical coherence tomography (OCT).
  
  
  RESULTS
  The average MPOD value was 0.41 ± 0.20 (range 0.07-0.79). There was no statistically significant difference between values in the left and right eye, with good interocular agreement (0.41 vs 0.40, r = 0.893, p < 0.01). Age significantly predicted MPOD score (R (2) = 0.07, p < 0.05). A subgroup analysis of patients who completed the dietary questionnaire revealed a close correlation between higher diet scores and higher MPOD (r = 0.720 p = 0.031). There was no effect of smoking, gender, or iris colour on MPOD values. There was no significant correlation between BCVA, macular OCT profiles, and MPOD.
  
  
  CONCLUSIONS
  Given that MPOD values are potentially affected by geographical variation, we have determined a mean MPOD value for healthy subjects in a population south of the equator, providing a reference point for future studies on Caucasian samples.
authors.affiliation: Department of Ophthalmology, Royal Hobart Hospital, 43 Liverpool St, Hobart, Tasmania, Australia, abell.robin@gmail.com.
authors.forename: Robin G
authors.initials: RG
authors.lastname: Abell
authors.forename: Alex W
authors.initials: AW
authors.lastname: Hewitt
authors.forename: Marko
authors.initials: M
authors.lastname: Andric
authors.forename: Penelope L
authors.initials: PL
authors.lastname: Allen
authors.forename: Nitin
authors.initials: N
authors.lastname: Verma
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001315:Australia; D003720:Densitometry; D005247:Feeding Behavior; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D014975:Lutein / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010783:Photometry / Q000379:methods*; D012160:Retina / Q000378:metabolism*; D012168:Retinal Pigments / Q000378:metabolism*; D011795:Surveys and Questionnaires; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology; D024341:Xanthophylls / Q000378:metabolism*; D055815:Young Adult; D065146:Zeaxanthins
chemical_list: D012168:Retinal Pigments; D024341:Xanthophylls; D065146:Zeaxanthins; D014975:Lutein