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Introduction.Introduction.
Aorta arise from the left ventricle.
It has ascending aorta
-arch of aorta.
-descending aorta.
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Vertebral artery.
Internal thoracic artery.
Thyrocervical trunk. Costocervical trunk.
Dorsal scapular artery.
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Left CCA begins in the thorax in front of the
trachea ,at the center of manubrium sterni.Right begins in the neck starts behind the
right sternoclavicular joint. It runs upwards with in the carotid sheath.Lies in front of the 4 cervical transverse
processes.At the level of thyroid cartilage it is divided
in to ECA,ICA.
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Carotid sinus-baroreceptors. Carotid body- chemoreceptors.
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It begins at the level of theupper border of the thyroid
cartilage.End in the cranial cavity by
supplying the brain.
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Cervical part- no branches. Petrous part-cortico tympanicbranch.
-Pterigiod branch. cavernous part- cavernous branches
-superior andinferior hyophyseal branches.
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Cerebral part.-opthalmic
branch
Anterior cerebral.Middle cerebral.
posterior communicating
branch.
Anterior choroidal
branch.
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Circle of willis is formedby the
vertebral artery . internal carotid artery.
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It runs forwards to reachthe longitudinal fissures
separating the cerebralhemisphere.
The arteries lies in closetogether and united to eachother by ant.
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It lies laterally in thedepth of the stem of the
lateral sulcus.
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It runs backwards andanatomies with the
posterior cerebral artery.
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Formed by the union ofright and left vertebral
arteries.It divide in to right and
left posterior cerebralarteries.
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Anterior , middle , posterior cerebralarteries give rise to cortical andcentral arteries.
Cortical supplies the cortex. Central branches antero -medial,antero lateral, postero -medial,postero -lateral dip deep to the
cerebrum and supplies the structuresdeep to it.
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Anterior, middleposterior cerebralarteries.
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Greater part of superolateral surface issupplied by middle cerebral artery.
A strip of 2cm wide along the
superomedial border extending fromthe frontal pole to the parito occipitalsulcus is supplied by anterior cerebral
artery. The area belonging to the occipitallobe, inferior temporal gyrus-
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Medial surface is by anterior cerebralartery.
Area belonging to occipital lobe
posterior cerebral artery. Lateral part of the orbital surface middle cerebral artery.
Tentorial surface PCA. Temporal lobe MCA.
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Main somatic motor andsensory area-MCA.
Except leg-ACA.Auditory area-MCA.Visual area-PCA.
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Due to anastomosis-equalises
the pressure on both sides.Blood brain barrier.End artery.
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The concept of the blood brainbarrier was first introduced byPaul Ehrlich.
The blood- brain barrier islocated in endothelial cells ofcapillaries of the brain.
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The mechanism for maintaining thisbarrier function lies in the capillarynetwork supplying blood to the
brain. Ion concentration levels inplasma may fluctuate abruptly. Theblood- brain barrier protects the
brain against surging fluctuations inion concentrations.
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1. Brain endothelial cells are joined by tightjunctions of high electrical resistanceproviding an effective barrier againstmolecules.
2. In peripheral endothelial cells there isgood transcellular movement of molecules.There is no such movement in brainendothelial cells.
3. Brain capillaries are in contact with footprocesses of astrocytes which essentiallyseparate the capillaries from the neurones.
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Cerebro vascular disease. Cerebral infarction.
Intra cerebral hemorrhage.
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Synthesis repertory. Head apoplexy. Head anoxia , cerebral. Head- anemia, brain of. Head-cerebral hemorrhage. Head-thrombosis. Generalities-paralysis after. Chest aneurysm of arteries.
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Brain.
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