Abstract
Purpose: :
Recent studies indicate that the density of macular pigment (MP) may play a central role in development and progression of age–related maculopathy (ARM). Many epidemiologic studies suggest a number of risk factors that may be associated with progression of ARM, like personal characteristics such as race, and ocular characteristics like iris pigmentation. Previously, we have shown that central macular pigment density (MPD) is similar in patients with ARM and healthy controls, but we found a large variation in MP distribution. In this study we investigated the race depending different pattern of MP distribution and their relation to central MPD in healthy subjects of various races.
Methods: :
All Subjects underwent MP density measurements (MPD) with a modified confocal scanning laser ophthalmoscope (HRA, Heidelberg Engineering, Germany) following a standard protocol. Inclusion criteria included age from 18 to 49 years, no presence of drusen in both eyes, and no other concomitant eye disease. MPD maps were calculated from autofluorescence images recorded at 488 nm and 514 nm. MPD was quantified from MPD maps within 0.5 degrees around the centre of the fovea.
Results: :
We included 92 healthy subjects (44 m, 52 f) aged from 18–49 (mean: 37.6 ± 4.4) with 3 different races/ethnicitys into this study. Thirty–two subjects (35%) were White non–Hispanic (WNH), 31 subjects (34 %) were Black, and 29 subjects (31%) were Asian. The mean MPD in Black and Asian was significant higher (0.58 ± 0.2 7 D.U.. Black, 0.57 ± 0.21 D.U.. Asian) than in the WNH (0.47 ± 0.25 D.U). The distribution of MP showed two main types: (1) central peak, (2) parafoveal ring. All Subjects with a central peak had significant lower MPD values than subjects with a parafoveal ring (0.38 ± 0.22 D.U. vs. 0.55 ± 0.21 D.U.). Among Black and Asian the parafoveal ring was more frequent than in WNH (87% Black, 91% Asian vs. 72% in WNH.
Conclusions: :
Our study with healthy subjects confirms previous work (Delori et al.) showing different pattern of macular pigment distribution in patients with ARM. A parafoveal ring in macular pigment distribution is more frequent in Black and Asian and associated with increased MPD. The association of different distribution pattern and their relevance as possible prognostic factor of ARM needs further studies.
Keywords: age-related macular degeneration • macular pigment • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)