9th June 2021

A 25-year-old man presents to A&E via ambulance, having been knocked off his bicycle

A 25-year-old man presents to A&E via ambulance, having been knocked off his bicycle by a car. A witness reports he hit his head and lost consciousness for a few seconds at the scene. He is complaining of a headache and has prominent bruising surrounding both of his eyes, but no other evidence of external head trauma. Neurological examination is normal.

Which of the following is the gold-standard investigation for the suspected diagnosis?

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