Assessing macular pigment optical density distribution by flicker photometry and imaging fundus reflectometry

This study was designed to test the feasibility of determining macular pigment optical density (MOD) distribution from a single digital retinal image and by flicker photometry. A 3CCD non-mydriatic retinal camera was modified by inserting a triple-bandpass filter in the light path between the flash lamp and the subject\u27s eye. Image analysis software was used to linearly combine the corresponding three (log-transformed) monochrome images in order to generate an MOD distribution map. Retinal images were obtained without dilation or bleaching, from both eyes of nine subjects. Additionally, a flicker photometer was modified to measure the MPOD of twelve subjects at four foveal locations. Results show that MPOD peaked at the center of the macula and decreased with eccentricity. Both methods show promise a simple and fast one objective the other subjective, means of assessing MPOD. They eliminate the need to bleach the visual photopigments or align separate images, as in traditional reflectoretry