Specialist expertise: Neuroradiology, Radiology, Headache, Head and Neck Radiology, Stroke, Neurology.
A stroke occurs when there is a problem with the blood supply to part of the brain, resulting in damage to brain cells.
Strokes are a medical emergency and urgent treatment is essential. The sooner a person receives treatment for a stroke, the less damage is likely to happen. If you suspect that you or someone else is having a stroke, phone 999 immediately and ask for an ambulance.
The effects of a stroke depend on where it takes place in the brain, and how big the damaged area is. The main symptoms of stroke can be remembered with the word FAST:
- Face – the face may have drooped on one side, the person may not be able to smile, or their mouth or eye may have drooped.
- Arms – the person may not be able to lift both arms and keep them there because of weakness or numbness in one arm.
- Speech – their speech may be slurred or garbled, the person may not be able to talk at all despite appearing to be awake, or they may have problems understanding what you're saying to them.
- Time – it's time to dial 999 immediately if you see any of these signs or symptoms.
There are 2 main causes of stroke:
- Ischaemic - where the blood supply to part of the brain is blocked, usually because of a blood clot. This is the most common type of stroke (85% of all cases).
- Haemorrhagic - where a weakened blood vessel supplying the brain bursts, leading to bleeding inside the brain or over its surface.
There is also a related condition called a transient ischaemic attack (TIA), where the blood supply to the brain is temporarily interrupted. This is known as a mini-stroke. It can last a few minutes or persist up to 24 hours.
Certain medical conditions and lifestyle factors increase the risk of having a stroke, including:
- high blood pressure (hypertension)
- high cholesterol
- irregular heart beat (atrial fibrillation)