Scanning electron microscopy in retinal research

The literature on scanning electron microscopy (SEM) pertaining to the retina has been surveyed and described. The first two papers on SEM and retina appeared in 1969. Most of the earlier studies concentrated on descriptions [by SEM alone, or with light microscopy (LM) and transmission electron microscopy (TEM)] of the appearance of various retinae and retinal cells [fish, newt, primates, rodents and rabbits, bullfrog]; or embryology of the chick retina. Two papers dealt with retinal disease. In all there were 25 papers in SEM/retinal research before and in 1974. Since 1975 there have been 111 papers which have used SEM in retinal research in very many different fields and in diverse ways, viz: the morphology of the retina, specific retinal cells, and the retinal vessels; embryology; labelling of retinal cells with surface markers; naturally occurring and experimentally-induced retinal disease; the effects of light, including lasers and photocoagulation, and other radiation on the retina, and phagocytosis and the retinal pigment epithelium (RPE). There have also been a number of papers concerned with techniques for SEM, applicable to retinal research, and several review articles. SEM has proven to be a very valuable adjunct to TEM in retinal research and it has become an accepted and almost routine way of extending and enhancing reports on retinal research. Properly used, SEM provides a laconic way of presenting information that might otherwise require many serial sections and long explanations.