Here we present a case of Idiopathic Intracranial Hypertension (IIH) with a rare clinical manifestation of oculomotor nerve palsy.

IIH, formerly known as pseudotumor cerebri, is a neurological condition characterized by increased intracranial pressure, and is usually seen in young obese females. It leads to papilledema and usually presents with headache and blurring of vision. Rarely, other cranial nerves may also be involved, most commonly the abducens nerve. Involvement of oculomotor nerve in IIH is extremely rare, and it may lead to misdiagnosis as compressive, vascular, or inflammatory pathologies, thus causing irreversible vision loss if not timely intervened.

A 60-years old male, with no comorbidities, presented with complaints of bifrontal headaches and acute onset vision loss, associated with features of raised intracranial pressure in the form of early morning and nocturnal worsening of headache and vomiting. On examination, he was found to have right sided ptosis with ophthalmoplegia and grade 3 papilledema. In view of oculomotor nerve palsy with pupillary involvement and papilledema, probable compressive and vascular causes were considered, and neuroimaging was done, which showed features suggestive of IIH (tortuous optic nerve, posterior globe flattening and optic nerve sheath prominence). CSF studies showed elevated opening pressure (27cm H2O), with normal biochemistry and cytology. With a  diagnosis of fulminant IIH, the patient was started on intravenous steroid pulse and Acetazolamide, following which he had improvement in his vision and ptosis.

Although IIH is a relatively common disease, variable presentations especially in males, can cause diagnostic challenges. It is important to consider it as a differential diagnosis in all cases of papilledema with ophthalmoplegia, as it is a treatable condition if diagnosed in the early stages.