The topography and age relationship of lipofuscin concentration in the retinal pigment epithelium.

Lipofuscin pigment granules (LPG) have been implicated as a marker of cellular aging. We have quantitated the content of LPG in human retinal pigment epithelium (RPE) as a function of age. Furthermore, topographic distribution of LPG within individual eyes was measured. Microspectrofluorometric determination of the distribution of LPG in human RPE cells revealed a progressive accumulation of LPG with increasing age. LPG first appeared in the basilar portions of RPE cells of young eyes. In older eyes, LPG formed into clumps and were noted to fill the entire RPE cell. The RPE topographic distribution of LPG revealed an increased accumulation in the posterior pole, with a consistent dip at the fovea. The ratio of lipofusion accumulation at the posterior pole, to the total RPE, remained constant throughout life.