Case 22 - Asymmetric pupils
Case
A 32 year old man presented with headache and an episode of right hand weakness and difficulty speaking.
He had been well in recent weeks. Two days previously he was lifting weights in the gym and then developed a sudden-onset pain in his left night neck radiating up to his jaw and the side of his head. He stopped his workout and went home, and took simple painkillers.
The pain persisted that evening, and when looking in the mirror he noted a drooping in his left eyelid, not sufficient to obstruct vision but evident when he looked in the mirror. He also noted his pupils were different sizes.
The pain persisted over the next two days. The morning of attending hospital he abruptly became unable to hold his phone properly, and his right hand felt numb. He tried to speak to his partner but had difficulty forming words. This resolved entirely within 10 minutes. He came to the emergency department.
On examination he had:
The rest of the examination, including eye movements, was entirely normal.
Where is the lesion?