A large stroke can cause extensive brain swelling. Because the skull is rigid, rising pressure can compress healthy brain tissue and threaten life. In carefully selected patients, decompressive craniectomy removes a section of skull and opens the covering of the brain to create space for swelling.

This procedure is sometimes informally called a decompressive craniotomy. The more accurate term is craniectomy when the bone flap is not immediately replaced. It is an emergency, life-saving operation rather than a treatment that reverses the brain tissue already damaged by the stroke.

When surgery may be considered: Decompressive surgery may be considered after a very large ischaemic stroke, often involving the middle cerebral artery territory, when swelling causes worsening consciousness or dangerous pressure. It may also be considered in selected haemorrhagic strokes or cerebellar strokes when a blood clot, swelling or hydrocephalus threatens the brainstem.

The decision is time-sensitive and based on age, stroke location and size, neurological condition, imaging, associated illness, response to medical treatment and the patient's known wishes. The stroke and neurosurgical teams discuss the expected chance of survival, potential disability and alternatives with the family whenever circumstances allow.

During decompressive craniectomy, the surgeon removes a planned section of skull to allow the swollen brain to expand outward rather than being compressed inward. The protective covering of the brain is opened and expanded. Depending on the cause, the surgeon may also address a haematoma or another source of pressure.

The bone is stored according to hospital protocol and may be replaced later in a separate operation called cranioplasty, once swelling has settled and the patient is medically ready. Until then, the patient requires protection of the unshielded area and specific mobility advice.

Intensive care and recovery:

After surgery, patients usually need neurocritical care with close monitoring of consciousness, breathing, blood pressure, temperature, seizures, swallowing and complications of immobility. Recovery is shaped mainly by the original stroke and not only by the operation.

Rehabilitation may include physiotherapy, speech and swallowing therapy, occupational therapy, cognitive rehabilitation and support for mood or behaviour changes. Some patients remain severely disabled despite successful control of swelling. Clear, compassionate counselling is essential throughout treatment.

Recognise stroke and act fast

Sudden facial droop, arm or leg weakness, speech difficulty, loss of vision, severe imbalance or an abrupt severe headache can indicate stroke. Seek emergency care immediately. Online appointment forms should never delay emergency stroke assessment.