Walsh & Hoyt: Neuropathic Toxicology of the Ocular Motor System

Exogenous agents sometimes cause peripheral ocular motor neuropathies. They can also cause supranuclear damage, extrapyramidal reactions, neuromuscular blockade, and myopathic damage. Toxic ocular motor neuropathies are rare. They may be confined to a single nerve or involve some or all of the ocular motor nerves. They may be associated with other signs and symptoms, either neurologic or systemic. There are no characteristic features that clearly identify them as toxic; unless the patient is rechallenged with a drug or poison and develops the ophthalmoplegia again, diagnosis may have to be tentative.