28th May 2025

A 63-year-old woman is brought into A&E by ambulance with a head injury following a fall backwards down the escalator in a shopping centre.

A 63-year-old woman is brought into A&E by ambulance with a head injury following a fall backwards down the escalator in a shopping centre.

On examination, you find difficulty looking downwards on testing extraocular muscle movement, a slight backward tilt of the neck and a resting tremor, rigidity, and bradykinesia.

CT head shows nil acute.

What is the most likely diagnosis?