II. Background
- Brain is supplied by two pairs of arteries
- Bilateral Internal Carotid Arteries (anterior)
- Bilateral Vertebral Arteries (posterior)
-
Anterior Circulation (internal carotid distribution)
- Supplies the frontal, parietal and part of the Temporal Lobe
-
Posterior Circulation (Vertebral arteries)
- Supplies the Occipital Lobe, Cerebellum, Brainstem and part of the Temporal Lobe
- Circle of Wills
- Anterior and Posterior Circulation are interconnected
- Redundant pathways (variable among individual patients).
III. Anatomy: Great Vessel origins
-
Vertebral Artery (Posterior Circulation) origins
- Both left and right Vertebral arteries arise in the upper chest from the subclavian arteries
- Common Carotid Artery (Anterior Circulation) origins
- Right common Carotid Artery originates from the subclavian artery (same as the Vertebral Artery)
- Origin is medial to the right Vertebral Artery origin
- Left common Carotid Artery originates directly from the aortic arch
- Left common carotid origin on the aorta is between the two subclavian artery origins
- Right common Carotid Artery originates from the subclavian artery (same as the Vertebral Artery)
IV. Anatomy: Anterior Circulation
- Main Source: Two Internal Carotid Arteries
- Internal Carotid Arteries divide to form
- Anterior Cerebral Artery (supplies medial Cerebral Hemisphere)
- Middle Cerebral Artery (supplies lateral Cerebral Hemisphere)
- Function
- Supplies Frontal Lobe, Parietal Lobe and superior Temporal Lobe (majority of cerebral circulation)
- Obstruction: Contralateral motor and sensory deficit
V. Anatomy: Posterior Circulation
- Main Source: Two Vertebral Artery
-
Vertebral arteries combine to form Basilar Artery
- Basilar divides to form posterior cerebral arteries
- Function
- Supplies Occipital Lobe, inferior Temporal Lobe, Brain Stem, Cerebellum
- Obstruction: Vision Loss and Vertigo
- See Vertebrobasilar CVA
- See Posterior Cerebral Artery CVA
- See Posterior Inferior Cerebellar Artery CVA
VI. Anatomy: Collateral Circulation (Circle of Willis)
-
Anterior Communicating Artery
- Connects anterior cerebral arteries together
- Posterior communicating arteries (2)
- Connects each internal carotid to Basilar Artery
VII. Anatomy: Images General
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
VIII. Anatomy: Images Venous
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
IX. Anatomy: Images Circle of Willis
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
- Lewis (1918) Gray's Anatomy 20th ed (in public domain at Yahoo or BartleBy)
X. References
- Gilman (1989) Manter and Gatz Essentials of Neuroanatomy and Neurophysiology, Davis, p. 216-21
- Goldberg (2014) Clinical Neuroanatomy, Medmaster, p. 6-15
- Netter (1997) Atlas Human Anatomy, ICON Learning, p. 130-9