13th June 2023

A 32-year-old woman is three weeks postpartum and develops gradual onset of a headache associated with vomiting and double vision

A 32-year-old woman is three weeks postpartum and develops gradual onset of a headache associated with vomiting and double vision. She has no relevant past medical history. She is admitted to hospital after becoming drowsy. On examination, she has a left 6th nerve palsy, and papilloedema is seen on fundoscopy. Blood tests, including CRP and ESR, are normal. She goes on to have a CT brain which shows ischaemia in the thalami and basal ganglia bilaterally.

Which of the following options is the most likely diagnosis?