CFF thresholds: relation to macular pigment optical density

Purpose: Only two small studies have evaluated the relation between individual differences in macular pigment (MP) levels and visual health prior to retinal disease. In this study, we assess the relation between MP and a general measure of visual health, the critical flicker fusion (CFF) threshold. Methods: A total of 134 subjects were assessed. CFF values were determined psychophysically using a 570 nm, circular 1-degree test field centrally fixated. MP optical density was measured using flicker photometry and a 1-degree circular 458 nm test field centrally fixated. Personal characteristics were determined by questionnaire. Results: Similar to past studies, we found a significant decline in CFF values with age (r = -0.56). There was a significant positive relationship (r = 0.30, p < 0.001) between MP density and CFF values that was independent of age. Conclusions: These results are consistent with a protective effect of MP on visual health across the lifespan.