A Rare Cause of Sudden Ptosis: Posterior Communicating Artery Aneurysm.

A forty-seven-year-old female patient was admitted to our clinic with sudden ptosis and diplopia without pain. She had no trauma or systemic disease history. Ptosis and mydriasis were observed in her left eye. Eye movement was restricted all directions without lateral. Isolated oculomotor nerve paralysis was diagnosed based on clinical findings, and posterior communicating artery aneurysm was observed in magnetic resonance angiography.