Scanning Electron Microscopy of Human Drusen

ABSTRACT

Drusen are small, yellowish deposits that form under the retinal pigment epithe lium with senescence or under certain pathological conditions. The present study examined these structures under the scanning electron microscope. Tissue came from the eyes of four donors, who were 22, 56, 60 and 61 years of age and who demonstrated widespread drusen of the posterior fundus. which was noted on postmortem examination. Specimens were prepared by detaching the retinal pig ment epithelium from Bruch's membrane and freeze fracturing the tissue. Drusen appeared as follows: 1. Distinct spherical masse, 10 X 9 um and 9 X 7 um in size, were situated between basement membrane of the retinal pigment epithelium and Bruch's membrane. The surface of the spherical masses were smooth. 2. Indistinct globular dome-like masses, with a harsh surface, were situated bet ween basement membrane of the retinal pigment epithelium and Bruch's membrane. These masses varied greatly in size. 3. Localized of dispersed small granular deposits of the inner collagen layer of Bruch's membrane were noted.