Investigations

Of necessity, the investigations required for any patient with an acute headache will depend upon the:

• Characteristics of the headache
• Age and co-morbidities of the patient
• Presence, or absence, of focal neurological signs

The most important investigation is the neurological examination itself. This must include:

• Alertness and cognitive function
• Limb power, tone, reflexes and sensation
• Pronator drift
• Cranial nerves
• Visual fields to confrontation
• Fundoscopy
• Cerebellar function

Most patients with a normal neurological examination and a ‘non-thunderclap’ headache will require no further investigation.

In about 10% of ED headache patients, the history and/or the examination will suggest the possibility of a secondary cause. Such patients will need to undergo a brain computerised tomography (CT) scan.