Lead, methanol, chloramphenicol, digitalis, ethambutol, and many other chemicals can also damage the optic nerve. Symptoms and Signs Visual dimness, photophobia, and ocular discomfort develop over days to weeks. It may become absolute and lead to blindness. Abnormalities are not usually seen, but a temporal disk pallor may develop later in the course. Treatment Vision may improve when the cause is removed immediately, unless the optic nerve has atrophied.
Chelation therapy is indicated in lead poisoning.
In idiopathic cases, treatment with oral or parenteral B vitamins before amblyopia becomes severe may reverse the condition. All rights reserved.