Circle of Willis (circulus arteriosus cerebri Willisii) - this anastomosis between vertebrobasilar and carotid system cerebral circulation. It is located at the base of the brain and is a network of arteries having an oval shape with the smallest transverse diameter. Its name is an anatomic education received by the name of the British physician who first described it.
In the formation of the circle of Willis basin participate artery following:
- The initial part of the posterior cerebral artery;
- Coupling back artery;
- Supraclinoid part of the internal carotid artery;
- Anterior communicating artery;
- The initial part of the anterior cerebral artery.
Functions of the circle of Willis
Willis circle connects each of the carotid arteries, not only between themselves but also with the system of the vertebral arteries. In normal development, the circle of Willis with his right and left halves are symmetrical structure.
The main function of the circle of Willis is to provide a full blood supply to certain areas of the brain, if caused by any cause impaired blood flow in one of the carotid arteries.
Diseases of the circle of Willis: Symptoms
Normal development of the circle of Willis does not occur more than 50% of people. The most common disorders of the arterial system are various types of communicating artery hypoplasia. Aneurysms of cerebral arteries and vessels often hit the circle of Willis.
When the circle of Willis vessels hypoplasia symptoms may be absent, of course, subject to the normal blood flow in the basins of other cerebral arteries. In this case, the pathology is detected as a random finding during diagnostic MRI.
As the results of a recent study conducted by researchers from the University of Pennsylvania, some people develop asymmetrical circle of Willis may cause frequent migraine attacks that occur with quite pronounced aura.
When the circle of Willis aneurysm symptoms are usually absent until then, until it comes gap. In the case of rupture of the damaged blood vessel starts to flow into the subarachnoid space. Patients complain of the terrible power of their headaches, which are often accompanied by nausea, vomiting, intolerance of bright light, stiff neck. With a significant hemorrhage is rapidly developing coma or patient dies almost immediately.
Diseases of the circle of Willis: Treatment
Many people learn that they have a version of the circle of Willis is not correct, despair, believing that they have a serious illness that requires a specific therapy. But in fact, the treatment of the circle of Willis is not carried out.
As we mentioned above, there are various options for the development of the circle of Willis and the ones that are the norm, there is not everyone. The vessels of the blood pool are designed not so much for the blood supply to the brain cells, how to compensate for the resulting thrombosis, cerebral blood flow by shifting blood from the blood of one basin to another. Therefore, in most cases, the pathology of the circle of Willis does not require treatment.
In the presence of an aneurysm one of the circle of Willis arteries - treatment is surgical and dressing aneurysm. In those cases where the opening of the aneurysm occurs, it should be conservative treatments such as and subarachnoid hemorrhage caused by any other cause.