Retinal macular pigment distribution measured by imaging fundus reflectometry

The existence of macular pigment (MP) in human eyes has been found to be of importance in the prevention of age-related macular degeneration (ARMD). A non-invasive technique of two-wavelength (460 nm and 560 nm) imaging fundus reflectometry was developed to measure the density distribution of this yellow pigment in retina in vivo. A total of 54 healthy human subjects were recruited and divided into three groups, which had average ages and sample sizes of 24.8+/- 2.6 (N=24), 40.2+/- 8.3 (N=13) and 67.5+/- 7.1 years (N=17) respectively. The MP distributions only in the horizontal meridian, which are fitted by Gaussian equation are presented in this report. The results show that the average peak MP densities are 0.48+/- 0.17, 0.46+/- 0.21 and 0.52+/- 0.13 in density unit (DU) from young to old groups respectively. No significant difference is shown in the statistical t-test between the groups of the MP density. The half MP distribution width (covers 95% of Gaussian area) are 5.4 degree(s)+/- 1.6 degree(s), 5.7 degree(s)+/- 2.3 degree(s) and 7.9+/- +/- 2.1 degree(s) from young to old groups respectively. It shows that the area of MP is increased approximately by a rate of 0.06 degree(s)/year. However, the cause of the MP extension in the retina with respect to age is unknown.