Page 303 - Medicine and Surgery

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Chapter 7: Cerebrovascular disease 299

Cerebral hemisphere haemorrhages may be caused Pathophysiology

by cerebral amyloid (accounting for 10% of haem- Extradural bleeds may result from a skull fracture
orrhages in people over 70 years of age). (usually the temporal bone with which the middle
Othercausesincludebleedingintoatumour,disorders meningeal artery is closely associated), causing the

of coagulation and rarely, vasculitis. rapid accumulation of a haematoma in the potential
Intracranial venous thrombosis may be complicated space between the skull and the dura.

by intracerebral haemorrhage (see page 300). Acute subdural haematomas may be seen after a head
injury,thelargebleedcausesariseinintracranialpres-
Clinical features sure and neurological deterioration.
Clinical signs are unreliable in distinguishing ischaemic Chronic subdural haematoma usually occurs as a re-
stroke from a haemorrhagic stroke, hence this is a di- sult of minor trauma, particularly in the elderly and
agnosis made following a CT brain scan. Headache and alcoholabusers.Bloodaccumulatesoverdaysorweeks
coma are more common in intracerebral haemorrhage. causingaslowgrowinghaematoma.Theremaybefur-
ther accumulation of fluid due to the osmotic pressure
Macroscopy of the degenerating blood, or further acute bleeds.
Blood clot which causes compression to the surrounding
brain. If the patient survives the haematoma is removed Clinical features
by phagocytosis, and replaced by gliosis. Extradural: There is generally a history of head injury.
Classically the patient has a brief loss of consciousness
Management at the time of injury, then a lucid interval followed
Resuscitate as necessary with management of the air- by development of headache, progressive hemipare-

way, breathing and circulation. sis and loss of consciousness. Cerebellar herniation
Reverse any clotting deficiency and avoid aspirin. (coning) causes an ipsilateral dilated pupil, followed

Hypertension needs to be treated cautiously, in the
by bilateral fixed dilated pupils, tetraplegia and death
early stages, to prevent hypoperfusion. Subdural: The onset may be indolent, and symptoms
Neurosurgery is rarely indicated, but is often required may fluctuate. Headache, drowsiness, and confusion

in cerebellar bleeds which may cause obstructive hy- (dementia if chronic) are common. Focal signs may
drocephalus. be present and epilepsy may occur.
Rehabilitation, ideally on a stroke unit, includes phys-

iotherapy, speech therapy, and occupational therapy Investigations
togainmaximalresolutionoftheneurologicaldeficits. The diagnosis is confirmed by a CT brain scan.
Anyrisk factors present, particularly hypertension,
should be managed to help prevent recurrence. Management
Extradural bleeds usually require emergency neuro-
surgery. Subdural haematomas may require surgery, but
Sub/extradural haemorrhage
are often managed conservatively with serial CT scans in
Definition patients without an acute history.
Bleeding from vessels either outside or inside the dura
mater.
Subarachnoid haemorrhage
Aetiology Definition
Tearingofbloodvesselswhichmaybetraumaticorspon- Spontaneous intracranial arterial bleeds into the sub-
taneous. Extradural haemorrhage results from tearing of arachnoid space.
the middle meningeal artery. Subdural haemorrhage is
caused by traumatic tearing of an epiploic vein. Risk Incidence
factors include a tendency to fall and clotting abnormal- 15 per 100,000 per year. Accounts for 5–10% of cere-
ities (including anti-coagulant therapy). brovascular disease.