Blood Supply

Inferior Sagittal Sinus

Inferior Sagittal Sinus The structure indicated is the inferior sagittal sinus. The brain is drained by a series of veins and venous channels which drain into large dural venous sinuses, which in turn ultimately drain to the internal jugular veins. The dural venous sinuses are lined by endothelium and located between the layers of the dura mater in the brain. The venous sinuses are different to other blood vessels as they do not have the same set of layers which form their walls, and do not contain valves, like veins. In addition to the venous sinuses, there are deep veins …

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inferior sagittal sinus

Internal Carotid Artery

Internal Carotid Artery The structure indicated is the internal carotid artery. The internal carotid arteries arise from the common carotid arteries. The brachiocephalic artery arises from the arch of the aorta and divides into the right subclavian artery and the right common carotid artery. There is no left brachiocephalic artery however, and the left common carotid arises directly from the aortic arch. There are three branches which come off the aortic arch: Brachiocephalic artery Left common carotid Left subclavian The common carotid arteries then divide into the external carotid and internal carotid arteries. The internal carotid artery ascends to supply the …

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internal carotid artery

Internal Thoracic Artery

Internal Thoracic Artery The structure indicated is the internal thoracic artery. The internal thoracic artery was formerly known as the internal mammary artery and is an artery located anteriorly in the thorax. It is a branch of the subclavian artery. The left subclavian artery comes directly off the arch of the aorta, whereas on the right side of the body, the brachiocephalic artery splits, giving rise to the right subclavian artery, and the right common carotid artery. The subclavian artery becomes the axillary artery at the lateral border of the first rib. It can be thought of in three parts, …

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internal thoracic artery

Left Coronary Artery

Left Coronary Artery The structure indicated is the left coronary artery. The left coronary artery (LCA) arises from the left aortic sinus of the ascending aorta. The left coronary artery has two terminal branches: Left anterior descending (LAD)/anterior interventricular Circumflex branch The left circumflex artery (LCX) supplies blood to the posterolateral left ventricle as well as the anterolateral papillary muscle and provides part of the supply to the left ventricle. The left anterior descending artery also supplies the left ventricle, and is responsible for the arterial supply to the anterolateral myocardium, the apex of the heart and the interventricular septum. …

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left coronary artery

Radial Vein

Radial Vein The structure indicated is the radial vein of the forearm. The venous drainage of the upper limb consists of a superficial system and a deep system. The superficial system drains to the deep system. The veins of the deep system accompany the arteries, and are known as venae comitantes which is the Latin for “accompanying veins” (vena comitans = singular). The veins which accompany the arteries are often in pairs, and are therefore frequently referred to in the plural form – venae comitantes. The radial veins are paired veins which accompany the radial artery in the forearm. The …

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radial vein

Small Cardiac Vein

Small Cardiac Vein The structure indicated is the small cardiac vein. The coronary sinus lies posteriorly on the heart in the coronary sulcus and receives four cardiac veins: Great cardiac vein Middle cardiac vein Small cardiac vein Posterior cardiac veins The coronary sinus returns deoxygenated blood to the right atrium of the heart, together with the superior and inferior vena cavae. The small cardiac vein lies in the coronary sulcus between the right atrium and the right ventricle. Learn more about the blood supply to the heart in this tutorial.

Descending Aorta

Descending Aorta The structure indicated is the descending aorta. The aorta consist of the ascending aorta, the aortic arch, and the descending aorta. The descending aorta is the largest artery in the human body and consists of a thoracic part and an abdominal part. The descending aorta passes through the aortic hiatus of the diaphragm together with the azygos vein and thoracic duct to enter the abdominal cavity where it is then referred to as the abdominal aorta. The abdominal aorta terminates by dividing at the aortic bifurcation into the common iliac arteries at the level of the fourth lumbar …

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descending aorta

Basilar Artery

Basilar Artery The structure indicated is the basilar artery. The basilar artery is formed from the union of the two vertebral arteries on either side. The vertebral arteries arise from the first part of the subclavian artery. Two other arteries are given off from the first part of the subclavian artery – the internal thoracic artery and the thyrocervical trunk. The vertebral and internal carotid arteries provide the arterial supply to the brain, forming the Circle of Willis at the base of the brain. After the vertebral artery is given off from the subclavian artery, it passes through the transverse …

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basilar artery

Left Gastric Artery

Left Gastric Artery The structure indicated is the left gastric artery. The left gastric artery is one of three branches of the celiac trunk. The celiac trunk is the first anterior branch that arises from the abdominal aorta. The abdominal aorta consists of anterior, posterior, and lateral branches. There are three anterior branches which supply the foregut, midgut and hindgut structures these are as follows: Celiac trunk – supplies foregut Superior mesenteric artery – supplies midgut Inferior mesenteric artery – supplies hindgut The celiac trunk arises from the abdominal aorta at the level of the upper part of the first …

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left gastric artery

Facial Artery

Facial Artery The structure indicated is the facial artery. The facial artery is a branch of the external carotid artery. The external carotid artery gives rise to 8 branches: Superior thyroid artery Ascending pharyngeal artery Lingual artery Facial artery Occipital artery Posterior auricular artery Maxillary artery Superficial temporal artery The maxillary artery and the superficial temporal artery are terminal branches of the external carotid artery, with the latter being the smaller of the two branches. The facial artery provides the major arterial supply to the face, terminating as the angular artery medially at the corner of the eye. It consists …

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facial artery