Cerebrovascular disease is the most common neurological disease. It represents up to 50% of the total. It is also the third leading cause of death in the world after heart disease and cancer. One of these pathologies are strokes, also known as stroke, infarction or strokes.
Thesebrain abnormalities caused by a pathological process of the blood vessels usually involve neurological alterations. The brain depends on the blood supply. As a result, neuronal damage occurs when the blood flow stops in a certain region for a few minutes. If it persists, it then causes neuronal necrosis and causes irreversible injury.
How to determine the damage of a cerebrovascular pathology?
They can be detected by radiological tests performed by doctors and neurologists.For example, a CT scan or magnetic resonance can provide a lot of information about the brain structures that have been affected.
In addition, it is important that the psychologist performs a neurological examination.We can thus obtain indications that can not be detected by radiological tests. These may be, for example, changes in behavior. Both are necessary for a more complete and rigorous diagnosis.
Characteristics of the cerebrovascular accidents
It is a type of cerebrovascular pathology formed by a heterogeneous group of disorders in which brain injury is produced by a vascular mechanism.Its prevalence has increased in recent decades. This is due to greater case detection through the use of neuroimaging techniques. Lifestyle also contributes to this increase.
The main risk factors are the processes that facilitate the accumulation of fats in the blood vessels, their calcification or the loss of flexibility. It is hypertension, cholesterol, diabetes or tobacco. They are more common after the age of 60. Strokescause linterruption of blood flow in a part of the brain.This lack of oxygen maintained over time in the affected area causes lesions or death of the brain tissue.
How are strokes manifested?
The symptoms of strokes are usually painless and transient. That's why they are often not diagnosed. However,its manifestation usually occurs on the opposite side of the body to the affected hemisphere. For example, if there is a decrease in blood flow in the right part of the brain, the consequences will tend to manifest in the left half of the body.
In addition, there is usually aloss of strength or numbness in the middle of the body (face, arm, leg …). They are also manifested by a sudden loss of vision, partial or total, in one or both eyes. There are also difficulties in speaking and understanding.
Types of stroke or stroke
Stroke produces disruption of normal cerebral blood flow. This is what we call cerebral infarction. He can becaused by obstruction (ischemic stroke) or haemorrhage (hemorrhagic stroke).Let's see this in more detail.
Ischemic stroke (obstructive)
The cause of ischemic stroke is theinterruption of blood flow due to blockage of the blood vessel.A clot circulates in the blood vessel to the brain. It anchors at a certain point in the artery and causes an obstruction. When less blood arrives causes a lower oxygen supply, which causes damage in the rainfed area.
The causes of this type of stroke are the lack of systemic irrigation, thrombosis or embolism.
- Thrombosis It occurs when a blood clot superimposed on an atheroma (a layer of solidified fat) narrows the cerebral blood vessel. It can appear suddenly.
- Embolism A clot, formed in the heart or as a fragment of a thrombus, is released into the bloodstream and blocks a distal artery.
The mortality rate of hemorrhagic stroke is higher than that of ischemic stroke. About30 to 50% of those who suffer such an accident die in the month following the hemorrhage.
The gravity in this case is greater because spilled blood can also cause damage. In other words, bleeding itself is a factor of injury. The cause of thesestroke results from the rupture of the weakened wall of an artery.The mechanisms that cause the rupture of a vessel are essentially: the aneurysm and hypertension.
- aneurism This is the dilatation, enlargement, localized bulge of a blood vessel, as a result of congenital weakness of the wall of an artery. The blood begins to fill the subarachnoid space. Intracranial pressure increases because the skull is not flexible in volume. This produces serious sequelae.
- Hypertension : it increases the risk of intracerebral hemorrhage. The blood is actually released into the brain and starts to damage various areas. The percentage of deaths is 80%. There is a risk of staying in a vegetative state.
The prevalence of stroke is currently 3.5% of the population over 64 years old.It is even more present among men from 65 to 74 years. But after 75 years, prevalence increases significantly among women.
Junqué, C. and Barroso, J. (2009).Neuropsychology Manual