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Updated: Jun 11, 2026

A Workflow to Quantitatively Determine Age-Related Macular Degeneration Lesion-Specific Variations in Fundus Autofluorescence
Published on: May 26, 2023
A central dip in the macular pigment spatial profile is associated with age and smoking
Mark L Kirby1, Stephen Beatty, Edward Loane
1Department of Chemical and Life Sciences, Waterford Institute of Technology, Waterford, Ireland.
Purpose:
To investigate the relationship between specific macular pigment (MP) spatial profiles and risk factors for age-related macular degeneration (AMD).
Methods:
The MP spatial profile of 484 healthy subjects was measured with customized heterochromatic flicker photometry (cHFP) and categorized into one of two profile types: typical exponential or atypical "central dip." Data on risk factors for AMD were obtained with a general health and lifestyle questionnaire. Dietary and serum concentrations of lutein (L) and zeaxanthin (Z) were also assessed.
Results:
The presence of the central dip MP spatial profile was significantly more common in older subjects (the mean ± SD age of subjects with a central dip MP spatial profile was 46.9 ± 12 years, whereas the mean age of subjects with a typical MP spatial profile was 41.8 ± 12 years; P = 0.004) and in current cigarette smokers (P = 0.031). Also, there was a significant age-related decline in central MP optical density (MPOD; 0.25° retinal eccentricity), but in the men only (r = -0.146, P = 0.049).
Conclusions:
A central dip in the MP spatial profile, seen in older subjects and in cigarette smokers, may represent an undesirable feature of macular pigmentation. Further research is needed in this area.
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