In human anatomy

Human anatomy

Human anatomy is primarily the scientific study of the morphology of the human body. Anatomy is subdivided into gross anatomy and microscopic anatomy. Gross anatomy is the study of anatomical structures that can be seen by the naked eye...

, the posterior communicating artery is one of a pair of right-sided and left-sided blood vessel

Blood vessel

The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...

s in the circle of Willis

Circle of Willis

The Circle of Willis is a circle of arteries that supply blood to the brain...

. It connects the three cerebral arteries of the same side. Anteriorly, it connects to the internal carotid artery

Internal carotid artery

In human anatomy, the internal carotid arteries are two major arteries, one on each side of the head and neck. They arise from the common carotid arteries where these bifurcate into the internal and external carotid artery, and they supply the brain....

 (ICA) prior the terminal bifurcation of the ICA into the anterior cerebral artery and middle cerebral artery

Middle cerebral artery

-External links:*...

. Posteriorly, it communicates with the posterior cerebral artery

Posterior cerebral artery

-External links: - Posterior Cerebral Artery Stroke* at strokecenter.org* at State University of New York Upstate Medical University* at psyweb.com* at neuropat.dote.hu...

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Pathology

Aneurysm

Cerebral aneurysm

A cerebral or brain aneurysm is a cerebrovascular disorder in which weakness in the wall of a cerebral artery or vein causes a localized dilation or ballooning of the blood vessel.- Signs and symptoms :...

s of the posterior communicating artery are the third most common circle of Willis aneurysm

Aneurysm

An aneurysm or aneurism is a localized, blood-filled balloon-like bulge in the wall of a blood vessel. Aneurysms can commonly occur in arteries at the base of the brain and an aortic aneurysm occurs in the main artery carrying blood from the left ventricle of the heart...

 (the most common are anterior communicating artery

Anterior communicating artery

In human anatomy, the anterior communicating artery is a blood vessel of the brain that connects the left and right anterior cerebral arteries....

 aneurysms) and can lead to oculomotor nerve

Oculomotor nerve

The oculomotor nerve is the 3rd of 12 paired cranial nerves. It enters the orbit via the superior orbital fissure and controls most of the eye's movements, including constriction of the pupil and maintaining an open eyelid by innervating the Levator palpebrae superiors muscle. The optic nerve is...

 palsy

Paralysis

Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...

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Fetal Origin of the Posterior Communicating Artery

The development of the PCA in the fetal brain occurs relatively late and arises from the fusion of several embryonic vessels near the caudal end of the posterior communicating artery.

The PCA begins as a continuation of the posterior communicating artery in 70-90% of fetuses with the remainder of PCAs having a basilar origin. The fetal carotid origin of the PCA usually regresses as the vertebral and basilar arteries become dominant and it finds a new origin in the basilar artery. About 20% of adults retain PCA origin from the posterior communicating artery, and in turn, the internal carotid arteries.