Fovea centralis in the human retina was studied with light and electron microscopes on a glutaraldehyde-osmium tetroxide fixed and epoxy resin embedded specimen. A relatively large amount of Müller cell processes is recognized at the center of the fovea. These cells constitute the floor of the fundus and possess a watery cytoplasm among central cone fibers in an area about 50μ in diameter. The mitochondria of the foveal cone tend to be dispersed in the inner segment and outer cone fiber. At the center, no ellipsoid is discernible in the inner segment of the foveal cone. The basal lamina along the vitreal surface is extremely thin at the fundus of the fovea. The center of the fovea externa, about 80μ in diameter, shows a slight convex elevation.
Yamada E. Some Structural Features of the Fovea Centralis in the Human Retina. Arch Ophthalmol. 1969;82(2):151-159. doi:10.1001/archopht.1969.00990020153002