0903 - Mechanisms of Headaches and Aura Flashcards
What are some serious causes of headaches? (6)
Cerebral tumours Raised ICP Intracranial haemorrhage Aneurysms Infection - meningitis/encephalitis Giant cell arteritis
What are the potential sources of headache pain?
Blood vessels - particularly meningeal arteries Meninges Scalp - skin/muscles Skull - bone/periosteum Face - CN-V Neck - Muscles/spine/ligaments Sensory nerves - activation of nociception NOT the brain.
What is the significance of a thunderclap headache?
Subarachnoid haemorrhage until proven otherwise.
What are the key elements of headache to elicit in the history?
Time course of onset Meningism? Raised ICP (postural headache/visual change/optic nerve swelling) Progressive over weeks or months Neurological deficit? Could it be giant cell arteritis?
What are the hallmarks of meningism? What signs can elicit the pain?
Headache
Neck Rigidity
Photophobia
Kernig’s sign (pain on straightening knee with hips flexed)
Brudzink’s sign (active flexion of hips/knees on passive flexion of neck).
What are the hallmarks of raised ICP?
Headache worse when lying flat
May also produce papilloedema, but this is a late sign.
What are the consequences of raised ICP?
Optic nerve compression - risk to vision
Reduced cerebral perfusion pressure (loss of gradient)
Herniation/coning in severe cases.
Outline subarachnoid haemorrhage
Bleed most common due to aneurysm rupture or angioma, which may follow exertion.
Described as a blow to the head, coming on over seconds to become generalised and then cause meningism. May present with impaired consciousness or focal neurological defects.
50% mortality, high risk of long-term disability.
⅓ have history of sudden, severe ‘sentinel headaches’.
What are the red flags for headaches and their potential causes
Sudden and severe - SAH/bleed, sentinel headache.
Febrile/meningism - Meningitis/meningoencephalitis
Focal neurology - Bleed, aneurysm, infarction
Chronic, progressive - Tumour
Postural (raised ICP) - Tumour, sinus thrombosis, IIH, chronic subdural bleed
Visual symptoms/polymyalgia/jaw claudication/temporal artery tenderness - Giant Cell arteritis
How does migraine typically present?
Episodic, unilateral, throbbing headache associated with nausea and photophobia. May be associated with (often positive) focal deficits, including Aura. Aura is believed to be caused by cerebral vasospasm and oligaemia.
