Pathology of Henle's fibre layer after occlusion of the central retinal artery.

THE outer fibre layer of Henle is the foveal portion of the outer plexiform layer of the retina. This layer is composed of the elongated inner processes of the foveal cones and rods which radiate with a peculiar slant away from the foveal pit. These inner processes, thus, represent short neurites connecting the visual cells with their bipolar cells. These latter neurons are shifted towards the retinal periphery and arranged in a circle around the fovea due to its special structure in man. Nutrition of the outer 120 microns of the human retina is believed to come from the choriocapillaris (Michaelson, 1965). In the foveal region even more of the retina is thought to be supplied from the choroidal side-since the fovea has no retinal blood vessels. Eye pathologists are, therefore, accustomed to see well-preserved outer retinal layers in routine stains even in late stages of complete occlusion of the central retinal artery. The present study is to present evidence of direct and irreversible damage to human Henle's fibre layer after occlusion of the central retinal artery, using a nerve stain.