Scientists look for ways to 'see' the threat of stroke from the brain's electrical mapping
Кhow to know if a person is at risk of a stroke? Risk factors have been known for a long time, but it has not yet been possible to predict when a stroke might happen. Meanwhile, every year a stroke occurs in about 0.5 million people in Russia, and in eight cases out of 10 people become disabled or die. And here is the news: scientists at Kazan University have learned to diagnose the precursors of stroke and other pathological conditions of the brain.
If it will be possible to bring this discovery to clinical practice, it will be easier to prevent acute vascular disorders, acting proactively. So, and deaths, and irreversible consequences, tearing people out of normal life, will be less. However, the researchers are still at the beginning of the journey.
Our brain is a complex living system that constantly emits electrical signals. Its activity varies depending on many factors. And by visualizing some of the changes can be judged about pathological processes.
Specialists of the laboratory "Neurophysiology" of the Institute of Fundamental Medicine and Biology of Kazan Federal University together with foreign colleagues studied the process of depolarization - a slow wave passing through the cerebral cortex, which is characterized by a short-term flash and then a long-term suppression (depression) of electrical activity of the brain.
Such a wave occurs in a variety of conditions, including ischemic stroke, brain injury, epilepsy, and migraine with aura. For example, in migraine, a few hours before the headache attack, various neurological disorders occur, which can affect the vestibular, speech, motor and other brain centers: the patient may have impaired vision, hearing, smell and motor activity.
These are all visible manifestations of the disease. Scientists set the task with the help of electroencephalography to recognize the threat of an approaching attack in advance. The same, scientists hope, it will be possible to understand the impending stroke and other developing pathologies.
So far, the experiments have been conducted on laboratory animals. But in the future, the researchers hope that EEG data will allow to predict the onset of stroke in humans, and then it will be possible to act ahead of time to avoid vascular catastrophe or at least reduce its consequences.
The authors of the idea say that existing electroencephalographs do not allow to differentiate electrical signals so as to distinguish between the precursors of stroke and other pathological conditions. Therefore, they have developed a prototype apparatus with which it is possible to register new additional parameters of electrical activity of the brain.
In the translation from a foreign language, stroke literally means "stroke". To this word - to make it easier to remember - experts and tied the main symptoms indicating a stroke.
The "U" stands for smile. Ask a person to smile, with a stroke he will not be able to do so, the corner of the mouth on the affected side is down;
"D" - movement. An important symptom is impaired movement, awkwardness in one half of the body. Ask the victim to stretch his arms forward in front of him, the affected arm will certainly lag behind the healthy one, and walking is difficult due to the paretic leg;
"A"-Articulation. With a stroke there is a violation of speech, it becomes unintelligible, inarticulate, or absent altogether;
"R" - decision. This is a reminder to people who are near the victim: making a decision to seek medical help.
Natalia Glotova, Head of the Medical Rehabilitation Department of the Federal Center for Brain and Neurotechnology of the Federal Center for Brain and Neurotechnology of FMBA of Russia:
- Back in the XIX century it was known - brain cells produce spontaneous electrical activity, later it was found that such activity varies depending on the brain's metabolism and various external influences on it. Colleagues in their study have further confirmed this.
Depolarization is just a process of excitation in nerve cells, which can have a pathological character and occur in various diseases of the central nervous system, not only in stroke. In some diseases - for example, epilepsy, the encephalogram is indeed the only and gold standard of diagnosis. But it is currently impossible to reliably establish that the patient has a stroke based on the results of EEG. Accurate non-invasive diagnostic methods are widely used: CT and MRI of the brain.
In relation to stroke, it is promising to work with risk factors - they are well known, studied, and by acting on them, we reduce the risk of vascular catastrophe.
What is a stroke? It is an acute disorder of cerebral circulation, accompanied by the development of symptoms due to damage to one or another area of the brain. Ischemic stroke occurs because of the restriction of blood flow to the brain area due to the occlusion of the intracerebral artery by a thrombus or a fragment of atherosclerotic plaque. In hemorrhagic stroke, the brain is affected due to rupture of an intracerebral vessel when blood is poured into the parenchyma and membranes of the brain.
So if we take care of our heart and vascular health, we thereby prevent stroke. This is why it is so important to keep blood pressure, cholesterol and blood glucose levels under control, and treat heart disease in a timely manner.
When ischemia occurs in the brain, it is manifested by a number of symptoms depending on the localization of the affected area.
Sensory, motor, speech disorders are frequent manifestations of stroke. Symptoms of stroke can also be visual impairment, double vision, dizziness, sudden loss of consciousness, memory, difficulty swallowing.
The main feature of all signs is their sudden onset against a background of relative well-being or the detection of symptoms immediately after sleep.
With such symptoms, it is necessary to immediately call an ambulance - the sooner the patient receives specialized care, the higher the chances for a favorable outcome.
Occasionally, distressing symptoms appear, but disappear after a while. In such cases, we use the term - transient ischemic attack (popularly called "microstroke"). This condition can be a precursor to an irreversible stroke. Therefore, even if the patient feels satisfactory and the symptoms of acute cerebral circulatory failure have disappeared, it is still necessary to seek help from a neurologist.