Fluctuating Pupil-sparing Oculomotor Nerve Palsy with Intracranial Spontaneous Dissecting Aneurysm

Oculomotor nerve palsy secondary to a compressive lesion is typically presented with clinical findings like anisocoria and ptosis. Seldom does its atypical presentation mimic the features of other neurological diseases. Hence, considering the underlying cause is vital, as it may rarely be the first sign of a ruptured or non-ruptured aneurysm, even if the absence of pupil involvement does not suggest such compressive causes. Herein, we reported the case of a patient who presented with fluctuating ptosis and diplopia secondary to spontaneous dissecting aneurysm of the internal carotid artery.