Third, fourth, and sixth cranial nerve palsies

Clinical manifestations of ocular motor palsies may differ according to the type and the localization of the lesions involving the third, fourth, and sixth cranial nerves. Topical diagnosis of the third, fourth, and sixth nerve palsies is therefore required before imaging studies and workup are performed. The development of modern imaging techniques has significantly improved the diagnosis of the disorders affecting the ocular motor nerves. This review covers the most important aspects, in terms of clinical signs and symptoms and differential diagnoses, of these cranial nerve palsies. The more recently published articles have added new disorders to the differential diagnosis of ocular motor palsy. Moreover, magnetic resonance imaging (MRI) has been confirmed to be the most important diagnostic tool in most cases. Finally, recently developed MRI techniques were presented and demonstrated to be more sensitive than conventional MRI in several cases.