Recovery of the rabbit retina after light damage (preliminary observations)

Abstract

The retinae of anaesthetised Dutch rabbits were exposed to one of two intensities of white light for a period of 1 h. After exposure the animals were allowed to recover for various periods up to 4 weeks. The animals were then killed, and retinal and choroidal tissue was taken for investigation by both light and electron microscopy. Exposure to the lower intensity produced disruption of the visual cell outer segments and distension of the pigment epithelium. Recovery from this insult was rapid although disturbances in rod disc stacking and a loss of cone cell outer segments were evident 4 weeks after exposure. Exposure to the higher intensity resulted in necrosis of visual cells and pigment epithelial cells. Non-native phagocytic cells were active in the removal of cellular debris. Recovery from this insult was not observed. Four weeks after exposure much of the previously illuminated retina was reduced to disorganised Müller cells and occasional macrophages.