When a stroke occurs, there is a sudden collapse of brain functions. The cause is either vascular occlusion or cerebral haemorrhage. Both of these cause similar symptoms, but the treatment is different. Therefore, it is vital that a stroke is quickly diagnosed and the exact causes are found.
A stroke is characterised by sudden circulatory disorder in the brain. The cause of this disorder is usually occlusion in a cerebral artery as a result of arteriosclerosis or an embolism. In this case, this is known an ischaemic stroke. However, the circulatory disorder can also be the consequence of cerebral haemorrhage. For example, if a brain aneurysm bursts. This is known as haemorrhagic stroke. Ischaemic and haemorrhagic stroke cannot be differentiated solely on the basis of the symptoms. Both lead to the death of brain cells and the loss of brain functions. It is only possible to recognise whether the stroke stems from a haemorrhage or occlusion of a cerebral artery with radiological examinations such as computed tomography and MRI.
The risk factors for a stroke are generally the same as for a heart attack: high blood pressure, high cholesterol, excessive weight, diabetes, smoking and lack of exercise. Another significant risk factor is atrial fibrillation. If cardiac arrhythmia occurs, blood clots can form in the heart that are transported to the brain and then cause an embolism there.
The symptoms of a stroke occur suddenly. Sometimes there are temporary symptoms beforehand, such as dizziness, short term vision problems, speech disorders, loss of feeling or problems walking. Such temporary episodes are known as transitory ischaemic attacks and constitute warning signs of a stroke. Depending on which region of the brain is affected, a stroke can cause different symptoms. Characteristic symptoms are one-sided paralysis, vision, speech or hearing disorders, major vertigo, sudden headaches or loss of consciousness.
Symptoms of this type which occur suddenly should be immediately checked by a doctor, even if they disappear again after a short time. Time is the most important factor to prevent permanent damage from a stroke.
The treatment depends on the severity of the stroke. If a cerebral haemorrhage is the cause, the source of the bleeding must usually be stopped with surgery. If vascular occlusion exists, there are medical and surgical options to deal with it. Find out more about the different treatment options in the endarterectomy and cerebral aneurysm surgery sections.
If there is a known risk of stroke (atrial fibrillation, transitory ischaemic attacks), blood thinners can be used as a preventative measure.