Cerebral circulation

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Cerebral circulation
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Cerebral circulation

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The anterior cerebral circulation is supplied by the pair of arteries.

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With cerebral circulation, cerebral stands for "brain," and circulation, refers to “blood flow.”

So, cerebral circulation is the movement of blood through the vessels that supply the brain and surrounding structures.

Our brain is responsible for complex functions such as thinking, feeling, memory, movement, vision, and speech.

Therefore, some of the devastating effects of oxygen deprivation to the brain include strokes, seizures, coma, and even death.

As a result, the brain requires a very efficient cerebral circulation to provide oxygen and nutrients, and remove carbon dioxide and wastes.

Now, like any other organ in the body, the blood supply to the brain, originates from the aorta.

Arising from the heart’s left ventricle, it goes on to form the aortic arch. Here, the brachiocephalic artery, originates first.

This branch gives off the right subclavian artery and the right common carotid artery.

Then a bit further along the aortic arch, the left common carotid artery arises, followed by the left subclavian artery.

The subclavian arteries give off right and left vertebral arteries, which ascend through the intervertebral feramina up to the brain.

Because the consequences of hypoxia to the brain are so devastating, the brain is safeguarded by having a dual circulation, an anterior circulation, originating from the carotids, and a posterior circulation, originating from the vertebral arteries.

The two circulations eventually meet up, creating what’s known as the circle of Willis.

Alright, the anterior circulation starts in the neck, where the common carotid splits into the external and internal branches, the internal carotid arteries, passes through the carotid canal of the temporal bone of the skull and into the cranial cavity to supply the brain.

Once, it enters the cranial cavity, the internal carotid artery gives off branches. First are the middle cerebral arteries that supply blood to the temporal and parietal lobes.

Second are the anterior cerebral arteries, which provide to the midline portions of the frontal lobes and superior medial parietal lobes of the brain.

Both anterior cerebral arteries are connected through the anterior communicating artery, forming the anterior portion of the circle of willis.

The posterior circulation starts with the vertebral arteries,which head up towards the cranium through the transverse foramina of the cervical vertebrae and then through the foramen magnum into the cranial cavity.