27th August 2020

A 32-year old woman is referred to A&E after seeing her GP with new-onset ptosis and miosis on her left side

A 32-year old woman is referred to A&E after seeing her GP with new-onset ptosis and miosis on her left side which she noticed yesterday. She has no history of surgery or trauma and is otherwise fit and well. Cranial nerve examination was normal. An x-ray is carried out in A&E, which is shown below. Which of the following is the cause of her problem?

Image: Wikipedia

Select the SINGLE most appropriate option from the list below. Select ONE option only.