Abstract
Purpose :
Spatial distribution of macular pigment (MP) is classified into four patterns; no ring, intermediate, ring-like, and central dip. Previous reports showed that ring-like was more frequent in women, smokers, and Africans. The association of MP distribution with age-related macular degeneration has also been suggested. We investigated MP optical density (MPOD) and its profile in an elderly Japanese population.
Methods :
Subjects were 92 eyes of 92 patients with no fundus diseases. Age was from 52 to 86 years (mean; 72±8.5), 36 men and 56 women. All were pseudophakic eyes to exclude any effects by cataract. MPOD was measured by Spectralis MultiColor instrument (Spectralis-MP, Heidelberg). The mean MPOD and total amount of MP at four eccentricities were evaluated. Reference point was set at 8.98°. Foveal architecture was evaluated with OCT. Dermal carotenoid concentration (DCC) was measured on the fingertip by reflection spectroscopy.
Results :
The mean MPOD at 0.23°, 0.51°, 0.98°, and 1.99° eccentricities was 0.75±0.17 (SD), 0.70±0.17, 0.68±0.16, 0.34±0.12 and total amount in the area within 0.43°, 0.98°, 1.99°, and 8.98° eccentricities were 304±72, 1449±329, 4387±1194, 19702±6633. The distribution patterns were; no ring 24 eyes (26%), intermediate 22 (24%), ring-like 39 (42%), central dip 7 (8%). The second peak on ring-like was located at 0.88±0.14° and the valley between the central peak and the second peak was located at 0.45±0.08°. There was no statistical difference in the distribution pattern by sex (p=0.23, χ2), age (p=0.51, ANOVA), body mass index (p=0.53, ANOVA), smoking (p=0.51, χ2), and DCC (p=0.065, ANOVA). Retinal thickness at the foveal center in ring-like was significantly smaller than that in no ring pattern (p<0.05).
Conclusions :
MPOD of the elderly Japanese were higher than has been previously reported in Caucasians. One possible reason may be a racial difference and another possibility is that this study included only pseudophakic eyes. The prevalence of ring-like in the present study was intermediate between Caucasians and Africans. In our previous study (Obana A. IOVS, 2017), we considered that MP is composed of two parts; MP present in the Müller cells at the fovea and MP in the Henle fiber layer at the parafovea. We hypothesize that the distribution pattern is dependent on the relative amounts of MP in these two parts.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.