Apoplexy, ischemic cerebral infarction, cerebral circulatory disorder, apoplectic insult.
Introduction
A stroke (medical term: apoplexy) is an undersupply of oxygen-rich blood to brain tissue and – depending on the duration of the undersupply – the associated death of the tissue.
What is a stroke?
A stroke is a damage to brain tissue as a result of a reduced oxygen supply to the brain. This reduced supply of oxygen to a defined area of the brain is due to a circulatory disorder. In 80% of cases, a stroke is caused by arteriosclerotic changes in the arterial walls (“vascular calcification”), an arterial thrombosis or an embolism. In all three cases, there is a partial or complete occlusion of brain vessels, so that less blood reaches the brain tissue and therefore less oxygen is available to the tissue.
Therapy
A stroke is an absolute emergency. In neurology and neurosurgery the concise guiding principle “time is brain” applies. Every minute counts, because the reduced perfusion of the affected brain area with oxygen-rich blood leads to the irreversible death of brain cells.
Unlike muscle or liver cells, brain cells are not able to regenerate. Should you notice any signs of a stroke, this is an absolute emergency indication. This means that the affected person must be transported as quickly as possible by ambulance to the hospital, where treatment will be initiated.
In principle, there are two different types of stroke. The ischemic stroke (anemic), and the hemorrhagic stroke (blood-rich). In almost 90% of the cases it is an ischemic stroke, i.e. a reduced blood supply to the brain area.
In the majority of cases, these are caused by an embolism – a tissue clot. The clot migrates, for example, from the carotid arteries into the brain, where it clogs a vessel. The larger the clot, the less far it travels in the increasingly fine vessels, and the larger the area it cuts off from the blood supply.
In this case, the neurologist or neurosurgeon gains access to the vascular system and works his way to the clot. This is then removed and removed from the body, for which various techniques are available. The “plug” is now removed, the vessel and its end branches can be perfused again and the brain area is supplied with oxygen again.
The situation is different with hemorrhagic stroke: although this form is only responsible in a good 10% of cases, it must be treated fundamentally differently. The cause here is a bleeding within the brain. Not only does this increase the intracranial pressure (see: increased intracranial pressure), since more and more (blood) volume is pumped into the skull, but is not drained via the vascular system.
The supply area is also no longer sufficiently supplied with fresh, oxygen-rich blood. The goal here must therefore be to “patch” the ruptured vessel and restore the blood flow. This is also done by means of access via the vascular system, or – in the case of already greatly increased intracranial pressure – by opening the skullcap, and treatment from the outside.
In summary, one can imagine an ischemic stroke, like when there is a knot in the garden hose that ensures that no more water comes out in the end. A hemorrhagic stroke would be a hole in the garden hose through which all the water comes out. Accordingly, the treatment of the two types of stroke is different.
