Light damage to the retina

The retinae of anaesthetised Dutch rabbits were exposed to light of various known intensities for a period of 1 h. After this period the animals were sacrificed and tissue taken for investigation by light and electron microscopy. Changes were apparent in the visual cells and retinal pigment epithelium only at the highest intensities employed. The retinal pigment epithelium and the outer nuclear layer exhibited mild oedematous changes. The major components to be affected were the visual cell outer segments. Marked disruption and vesiculation were features of the cone outer segments, which was in distinct contrast to the focal damage observed in the rod outer segments.