History and exam
Key diagnostic factors
common
presence of risk factors
Key risk factors include smoking, moderate- to high-level alcohol consumption, previous subarachnoid haemorrhage (SAH), family history of SAH, and heritable connective tissue diseases.
headache
New, never-before-experienced headache suggests ruptured cerebral aneurysm.
The character of the headache can be quite variable.
Other diagnostic factors
uncommon
seizures
New, never-before-experienced focal or generalised seizures.
nuchal rigidity
New neck stiffness that includes pain on stretching the neck meninges with manoeuvres. More commonly found in subarachnoid haemorrhage.
decreased level of consciousness
More commonly found in subarachnoid haemorrhage. Usually related to concurrent hydrocephalus.
focal neurological deficit
Variable, depending on mass effect of aneurysm and/or haematoma. More commonly found in subarachnoid haemorrhage.
The classic syndrome is that of a third nerve palsy with pupillary dysfunction from a posterior communicating artery aneurysm exerting mass effect.[24]
Risk factors
strong
smoking
moderate- to high-level alcohol consumption
Moderate- to high-level alcohol consumption is an independent risk factor for aneurysmal subarachnoid haemorrhage.[12]
family history of subarachnoid haemorrhage
Highest in siblings. No single Mendelian model but several possible patterns of inheritance identified. Most likely autosomal dominant.[8]
previous subarachnoid haemorrhage
Multiple aneurysms are consistently seen in follow-up studies of patients with subarachnoid aneurysmal haemorrhage (SAH). One cohort study followed up 610 patients who had previous SAH and detected aneurysms in 96 (16%) patients, after a mean interval of 8.9 years.[16]
heritable connective tissue disease
Considered specifically in patients with autosomal dominant polycystic kidney disease, Ehlers-Danlos syndrome type IV, neurofibromatosis type 1, and Marfan's syndrome.[8]
weak
hypertension
Hypertension is a weak risk factor for aneurysm formation and rupture, although population studies examining its importance have produced conflicting results.
head trauma
May cause damage to the vascular wall leading to aneurysm formation.
intracranial infection
May cause damage to the vascular wall leading to aneurysm formation.
tumour
The presence of an intracranial tumour can lead to aneurysm formation.
arteriovenous malformations or fistulas
Arteriovenous malformations or fistulas in the intracranial circulation can develop into aneurysms.
drug abuse
Drug abuse can lead to cerebral aneurysm formation (particularly amphetamines, cocaine, and ecstasy).[17]
Use of this content is subject to our disclaimer