As you know, for the normal functioning of the central nervous system, in particular the brain, the level of oxygen and the amount of glucose are extremely important. These substances are delivered to the nerve tissues along with the blood. And the transport system in this case is the arteries of the brain. Today, many people are interested in additional information about the blood supply system of the brain. What vessels carry blood to the CNS? How is the outflow of blood carried out? What are the symptoms of impaired blood flow? What diagnostic measures are the most effective? What is the difference between CT and MRI of the brain? How to eliminate problems with blood circulation and can you do it yourself? The answers to these questions will be interesting.
General data
The human brain needs enough resources to function properly. In particular, the central nervous system is extremely sensitive to the level of oxygen and sugar in the blood. About 15% of all circulating blood passes through the vessels of the brain. On average, the total brain blood flow is 50 ml of blood for every 100 g of brain tissue per minute.
There are four main cerebral arteries that fully meet the needs of this organ: two vertebral and two internal carotid. Of course, it is worth considering the anatomical features of the body. What areas of blood supply to the brain exist? What happens when blood flow is interrupted?
Internal carotid arteries
These vessels are branches of the carotid artery (common). As you know, the common carotid arteries (right and left) are located in the lateral parts of the neck. If you put your fingers to the skin, then through the tissues you can easily feel the characteristic pulsation of the vascular walls. Approximately at the level of the larynx, the common carotid artery branches into external and internal. The internal one penetrates through a hole in the skull, supplies blood to the tissues of the brain and eyeballs. The external carotid artery is responsible for the blood supply to the skin of the head and neck.
Vertebral arteries
Considering the arteries of the brain, one cannot fail to mention the vertebral arteries. They branch off from the subclavian arteries, after which they pass through the openings of the transverse processes of the cervical vertebrae, and then penetrate into the cranial cavity through the foramen magnum. It is worth noting that after entering the cranial cavity, the vessels are connected to each other, forming a very specific arterial circle.
The connecting arteries of the circle of Willis are a kind of "security system". If the blood flow in one of the vessels is disturbed, then due to the presence of the arterial circlethe load is redirected to other, he althy arteries. This helps to maintain blood circulation in the brain at the right level, even if one of the vessels is out of order.
Cerebral arteries
The cerebral arteries branch off from the internal carotid artery. The anterior and middle vessels provide nutrition to the deep brain regions, as well as the surfaces of the cerebral hemispheres (internal and external). There are also posterior vertebral arteries, which are formed by branching from the vertebral arteries. These vessels carry blood to the cerebellum and brain stem. The large cerebral arteries diverge, forming a mass of small vessels that sink into the nervous tissues, providing them with food. According to statistics, cerebral hemorrhages in most cases are associated with a violation of the integrity of the vessels described above.
What is the blood-brain barrier?
In modern medical practice, the term "blood-brain barrier" is often used. This is a kind of substance transport and filtration system that prevents certain compounds from entering the capillaries directly into the nerve tissues. For example, substances such as s alt, iodine, and antibiotics do not normally penetrate the brain tissue. That is why during the treatment of brain infections, antibacterial agents are injected directly into the cerebrospinal fluid - so the antibiotic can penetrate into the brain tissue.
On the other hand, alcohol, chloroform, morphine and some other substances easily penetrate the blood-brain barrier, whichexplains their intense and almost instantaneous effect on brain tissue.
Carotid basin: anatomy features
This term refers to a complex of major carotid arteries that originate in the chest cavity (including branches from the aorta). The carotid pool provides blood to most of the brain, skin and other structures of the head, as well as the visual organs. Violation of the functioning of the structures of this pool is dangerous not only for the nervous system, but also for the whole organism. The most common cause of circulatory problems is atherosclerosis. This disease is associated with the formation of a kind of plaques on the inner walls of blood vessels. Against the background of atherosclerosis, the lumen of the vessel narrows, the pressure in it rises. The development of the disease is associated with a number of dangerous consequences, including embolism, ischemia and thrombosis. These pathologies, in the absence of timely treatment, can end in the death of the patient.
Vertebrobasilar system
In modern medical practice, the term vertebrobasilar system, or Zakharchenko's circle, is often used. This is a complex of vertebral vessels. The structure also includes the basilar artery. The vertebral vessels, as already mentioned, originate in the chest cavity, and then pass through the canals of the cervical vertebrae and reach the cranial cavity. The basilar artery is an unpaired vessel that is formed by joining the vertebral arteries. This part of the bloodstream provides nutrition to the posterior parts of the brain, including the cerebellum, medulla oblongata and partdorsal.
Losses of the above-described vessels (from mechanical trauma to atherosclerosis) often end in thrombosis. Violation of the blood supply to those structures of the brain that form this organ can lead to the appearance of various neurological symptoms and stroke.
Veins and outflow of blood
Many people are interested in the question of how the arteries and veins of the brain work. We have already looked at the pathways by which blood enters the brain. As for the outflow system, it is carried out through the veins. The superior and inferior superficial veins collect blood from the subcortical white matter and the cortex of the cerebral hemispheres. Through the cerebral veins, blood is collected from the cerebral ventricles, the internal capsule, and the subcortical nuclei. All of the above vessels subsequently flow into the venous sinuses of the dura mater. From the sinuses, blood flows through the vertebral and jugular veins. The sinuses communicate with the external vessels through the diploic and emissary veins. By the way, these vessels have some features. For example, the veins that collect blood from brain structures lack valves. There is also a large number of vascular anastomoses.
Blood flow in the structures of the spinal cord
The spinal cord receives blood from the anterior, two posterior and radicular-spinal arteries. The posterior spinal vessels give rise to the vertebral (spinal) artery - they are directed along the dorsal surface of the spinal cord. The anterior spinal artery is also a branch of the vertebral vessels - itlies on the anterior spinal surface.
The above vessels feed only the first two or three cervical segments. The circulation of the rest of the spinal cord is carried out due to the work of the radicular-spinal arteries. In turn, these vessels, which descend and run along the entire spine, receive blood by communicating with the ascending neck, intercostal and lumbar arteries. It should also be said that the spinal cord has a highly developed system of veins. Small vessels take blood directly from the tissues of the spinal cord, and then flow into the main venous channels that run along the entire spine. From above, they connect with the veins of the base of the skull.
Impaired cerebral circulation
Considering the arteries of the brain, one cannot but mention the pathologies that are associated with circulatory disorders. As already mentioned, the human brain is extremely sensitive to oxygen and blood sugar levels, so the deficiency of these two components negatively affects the functioning of the whole organism. Prolonged hypoxia (oxygen starvation) leads to the death of neurons. The result of a sharp drop in glucose levels is loss of consciousness, coma, and sometimes death.
That is why the circulatory apparatus of the brain is equipped with a kind of protective mechanisms. For example, the venous system is rich in anastomoses. If the outflow of blood in one vessel is disturbed, then it moves in a different way. The same applies to the circle of Willis: if the current in one artery is disturbed, its functions are taken overother vessels. It has been proven that even if the two components of the arterial circuit do not work, the brain still receives enough oxygen and nutrients.
But even such a well-coordinated mechanism sometimes fails. Pathologies of the cerebral vessels are dangerous, so it is important to diagnose them in time. Frequent headaches, recurrent dizziness, chronic fatigue are the first symptoms of cerebrovascular accident. If left untreated, the disease can progress. In such cases, a chronic cerebrovascular accident develops, dyscirculatory encephalopathy. Over time, this ailment does not disappear - the situation only gets worse. The lack of oxygen and nutrients leads to the slow death of neurons.
This, of course, affects the work of the whole organism. Many patients complain not only of migraines and fatigue, but also of tinnitus, recurrent eye pain (for no apparent reason). There may be mental disorders and memory impairment. Sometimes there is nausea, tingling on the skin, numbness of the extremities. If we talk about acute cerebrovascular accident, then it usually ends with a stroke. This condition rarely develops - the heartbeat quickens, consciousness is confused. There are problems with coordination, speech problems, divergent strabismus, paresis and paralysis develop (usually one-sided).
As for the causes, in most cases, the violation of blood flow is associated withatherosclerosis or chronic arterial hypertension. Risk factors include diseases of the spine, in particular osteochondrosis. Deformation of the intervertebral discs often leads to displacement and compression of the vertebral artery, which feeds the brain. If you notice any of the above symptoms, contact your doctor immediately. If we are talking about acute circulatory failure, then the patient needs immediate medical attention. Even a few minutes of delay can harm the brain and lead to a host of complications.
CT and MRI of the brain
The price in Moscow (as in any other city) for such procedures is quite high. Therefore, many people are interested in additional information about such diagnostic measures. These procedures are considered the most informative. So what is the difference between CT and MRI of the brain? In fact, the purpose of such procedures is the same - scanning the human body with the further construction of an image of the body "in section".
Nevertheless, the scheme of operation of the devices themselves is different. The operation of ART equipment is based on the behavior of a hydrogen atom in a powerful magnetic field. But with computed tomography, information about tissues and organs is received by special detectors that capture radio emission that has passed through the human body thanks to X-ray tubes. Both devices transmit all data to a computer, which analyzes the information, forming images.
How much does a brain MRI cost? Prices in Moscow fluctuate depending on the policy of the chosen clinic. Studycerebral vessels will cost about 3500-4000 rubles. The cost of CT is slightly lower - from 2500 rubles.
By the way, these are not the only diagnostic measures that help diagnose certain blood flow disorders. For example, angiography of the arteries of the brain provides a lot of useful information. The procedure is carried out by injecting a special contrast agent into the vessels, the movements of which are then monitored using X-ray equipment.
What drugs are prescribed to improve blood circulation in the brain? Drugs and proper diet
Unfortunately, many people are faced with such a problem as a violation of blood flow in the vessels of the brain. What to do in such cases? What drugs are prescribed to improve blood circulation in the brain? The drugs, of course, are selected by the attending physician, and it is not recommended to experiment with such drugs on your own.
As a rule, the treatment regimen includes drugs that prevent platelet aggregation and blood clotting. Vasodilating drugs have a positive effect on the state of nerve tissues. Nootropics also help improve blood circulation and, accordingly, tissue trophism. If indicated, the doctor may prescribe psychostimulants.
People at risk are advised to reconsider their lifestyle and, first of all, nutrition. Experts advise to include in the menu vegetable oils (linseed, pumpkin, olive), fish, seafood, berries(cranberries, lingonberries), nuts, sunflower and flax seeds, dark chocolate. It has been proven that regular consumption of tea has a positive effect on the circulatory system.
It is important to avoid physical inactivity. Feasible and regular physical activity increases blood flow to tissues, including nervous ones. Sauna and bath have a positive effect on the circulatory system (in the absence of contraindications). Of course, if you have any disorders and alarming symptoms, you should consult a doctor and undergo a medical examination.
