Very large neurons of the inner retina of humans and other mammals.

Large ganglion cells, called parasol cells, are known to occur in the Golgi-stained, human retina. This report describes a population of much larger cells that is not stained by Golgi technique. These cells may be located in the human ganglion cell layer using Nomarski differential interference contrast optics and unstained, flatmounted tissue. These cells are regularly distributed in young and old adults in a Gaussian fashion along the radii that extend from the perimacula toward the far periphery. The author did not find the cells in the central retina. The most frequent (J-type) cells have soma diameters between 26 and 40 microns. Rare (S-type) cells measure up to 55 microns in diameter. Many cells have processes that appear to be axons or dendrites. These cell types may be especially sensitive to damage early in diseases of the inner retina.