Isolated third cranial nerve palsy in benign idiopathic intracranial hypertension

Idiopathic intracranial hypertension (IIH) is marked by increased intracranial pressure without any accompanying evidence of clinical, imaging or laboratory findings of intracranial pathology. In addition to headache, nausea and vomiting, typical symptoms might also include diplopia, photophobia and blurred vision. Third nerve palsy is rarely linked to IIH, although sixth nerve palsy is reported in the majority of individuals with IIH. This paper describes the unique case of a woman patient in her 50s with solitary IIH-related oculomotor nerve palsy. Dilated pupils, ptosis and medial rectus palsy of the right side were observed during the neurological examination, and grade 1 papilledema was found during the fundus examination. Based on the features of elevated intracranial pressure observed on MRI/magnetic resonance venography and CT scans, IIH was recognised as the most plausible explanation for the patient's symptoms.