Scanning Electron Microscopic Findings of Human Bruch's Membrane

ABSTRACT

Anatomical examinations on Bruch's membrane have almost been by light microscopy or transmission electron microscopy. Scanning electron microscopy allowed us to evaluate surface features topographically. Each layer of Bruch's membrane was exposed sequentially to mechanical or enzymatic treatment of the retinal pigment epithelium choroid complex from human cadavar eye. The authors examined the surface features of the membrane by dry-cracking scanning electron microscopy. The basement membrane of retinal pigment epithelium appeared like a smooth thin plastic membrane which was framed by collagen fibers. The inner collagenous layer was composed of many collagen fiber bundles which were placed in order and the ground substance between them was not visible. Elastic layer of Burch's membrane appeared to be coarse and fine fibers matted together by some amorphous substance. This layer had many openings on its solid sheet and the outer collagenous zone was visible though these openings.