Abstract
Purpose: :
We have shown that central MP density is similar in patients with age-related maculopathy and healthy controls, but we found a large variation in spatial distribution of macular pigment (MP). To investigate this variability, we investigated whether the spatial distribution of MP is influenced by gender and by the diameter of foveal depression.
Methods: :
The study population was 64 subjects (34 f, 30 m) aged from 21 to 49 years (mean 37±6 years), with normal retinal status and clear media. The MP distribution was measured with a modified confocal SLO using the autofluorescence (AF) method. Analysis of AF-images at 488 and 514 nm yielded the MP density map, the central density of MP (MPDc), the MP density profile, and the full width at half (central) maximum of the distribution (FWHM). Additionally, we used spectral-domain OCT (Spectralis HRA+OCT) to measure the diameter of foveal depression (diameter of the ring of highest retinal thickness) in high resolution scans.
Results: :
Using objective criteria, we grouped the shapes of the MP spatial distribution into two types: (1) those with a central "peak" and a monotonic decrease of MP with increasing eccentricity, and (2) those with a "ring" of higher density at an eccentricity of 0.6-1.4° or a marked inflection on the slope of the MP profile. Mean MPDc was 0.44±0.17 DU (range 0.17-0.91 DU), and did not significant differ for the two types of distribution. The mean MP distribution width FWHM was 2.0°±0.7°(range 1.5-2.7°). MPDc and FWHM were not significantly different for the two distribution types. Mean diameter of fovea depression was 0.31±0.1 mm (10.7±0.3°). The foveal depression in subjects with a "ring" MP distribution tended to be wider than in those with a central "peak" type distribution (p=0.1). In regard to gender relationships, women were more likely to exhibit profiles of the "ring" type (p=0.01). In addition women exhibited a tendency to have a wider MP distribution (p=0.1) and tendency to have a wider foveal depression (p=0.1).
Conclusions: :
Differences in MP spatial distribution may be related to, among other factors, anatomical differences in the shape of the foveal depression in women and men.
Keywords: macular pigment • clinical (human) or epidemiologic studies: risk factor assessment • macula/fovea