Morphological assessment of visual dysfunction.

The eye is an isolated unit but with a potentially high degree of sensitivity to toxic substances. The multiplicity of types of reaction to injury reflects the unique anatomical, physiological and biochemical features of the eye. The following are examples of such: The albino rat is not a good model for retinal toxicity because of problems of phototoxic retinopathy, the absence of pigment within the pigment epithelial layer and the high incidence of spontaneous retinal pathologies; The ocular toxicity of a compound cannot be anticipated from its chemical structure; Pharmacological side effects are similar between species, and are predictive for man; Mechanisms of ocular toxicity are poorly understood.