The etiologies of isolated fourth cranial nerve palsy: a 10-year review of 158 cases.

In our series, most of the isolated fourth nerve palsy cases were congenital, followed in frequency by microvasculopathy and intracranial tumor, as in many studies. In cases of microvasculopathy, the clinical signs and symptoms resolved within 6 months in all cases: observation was sufficient, with no necessity for neuroimaging. However, neuroimaging should be considered in cases with atypical presentations, such as headache, periorbital pain, or if there is rapid progression or no recovery.