Bleeding in the brain Flashcards
What is an arteriovenous malformation (AVM)?
- complex tangle of arteries and veins connected with fistulas, creating a shunt (no capillary bed)
- common cause of haemorrhage in adults < 40
Where do AVMs cause bleeding?
Most commonly intracerebral
Can be intraventricular or subarachnoid
Which investigation is best for AVMs?
Catheter angiography
CT angiogram can be used in emergencies
Where is the blood in a subarachnoid haemorrhage?
Subarachnoid space, between arachnoid membrane and pia
What is the most common cause of a SAH?
Ruptured berry/saccular aneurysm
Where do berry aneurysms most commonly arise?
Circle of Willis - anterior circulation (internal carotid territory) 90%
Posterior 10%
Name 3 risk factors for berry aneurysms
POLYCYSTIC KIDNEY DISEASE
Hypertension
Smoking
What are the clinical features of a SAH?
Sudden onset thunderclap headache (occipital)
Neck stiffness and photophobia
N&V
How do you diagnose a SAH?
CT
What should you do if CT is normal in a suspected SAH?
Lumbar puncture
–> xanthochromia (yellow discolouration) or blood stained CSF
What are the complications of SAH?
Vasospasm: delayed neurological deficit, peak 3-14 days
- treat with nimodipine (prevent spasms) and BP control
Re-bleeding
Hydrocephalus
Seizures
Hyponatraemia
Where does the bleeding occur in a subdural haemorrhage?
Between dura mater and arachnoid membrane
Which vessels bleed to cause a subdural haemorrhage?
Bridging veins
Which types of patients get subdural haemorrhage?
Elderly, alcoholic –> frequent falls
Anti-coagulated
Sign of NAI in babies
Which investigation would you do for a subdural haemorrhage and what would it show?
CT –> crescent shaped haemorrhage
crosses suture lines but not midline
What are the clinical features of a subdural haemorrhage?
Headache
Impaired consciousness + confusion
Focal neurological signs
Memory impairment
What is a cavernous malformation?
Well circumscribed, benign vascular lesion (resembles a mulberry)
How would you investigate a cavernous malformation?
MRI gold standard –> popcorn like appearance
CT if acute haemorrhage
Angiogram NOT helpful as low flow lesions, but can rule out other conditions
Where is the blood in an extra/epidural haemorrhage?
Between the dura and bone
Which vessels are the most common cause of bleeding in an extradural haemorrhage?
Middle meningeal artery
- anterior branch vulnerable as lies beneath pterion
- parietotemporal skull fracture
What is the clinical presentation of an extradural haemorrhage?
Brief LOC followed by lucid interval –> deterioration
- headache, vomiting, contralateral hemiparesis
- ipsilateral pupillary dilatation (CN3)
- rapid decline as high pressure artery source (unlike subdural with low pressure veins)
What would the CT show in an extradural haemorrhage?
Lens/lentil shaped haemorrhage
Mass effect + herniation (midline shift)
