12-1 Brain CNS Blood Supply Flashcards
<p>A: The \_\_\_\_\_ Artery (\_\_\_\_\_ circulation) perfuses MOST of the CEREBRUM.</p>
<p>It bifurcates into the \_\_\_\_\_\_ and \_\_\_\_\_\_ artery</p>
<p>B: What are the 3 daughter branches of this Artery?</p>
<p>The INTERNAL CAROTID Artery (ANTERIOR circulation) perfuses MOST of Cerebrum.</p>
<p>It bifurcates into..... [Anterior Cerebral a.]---->medial cortex and [middle cerebral a.]-->lateral cortex</p>
<p>B: Daughter branches: 1) ophthalmic artery 2) ANT Choroidal a. 3) POST communicating a.</p>
<p>A: The \_\_\_\_\_ system (\_\_\_\_\_\_circulation) perfuses Brainstem, Cerebellum & Spinal Cord. It Bifurcates into \_\_\_\_ cerebral arteries.</p>
<p>B: Describe this system</p>
<p>C: What are the daughter branches for each of these Arteries?</p>
<p>The <strong>V</strong>ERTEBRO<strong>B</strong>ASILAR system (POSTERIOR circulation) perfuses Brainstem, Cerebellum & Spinal Cord.</p>
<p>B: 2 Vertebral a. Join---> 1 Basilar ARtery-->Bifurcates into <strong>PCA</strong>[POST cerebral a.]</p>
<p>C:</p>
<p>*<em>Basilar</em> branches = [(<strong>AICA</strong>) ANT inf. cerebellar a.] & [(<strong>SCA</strong>)SUP cerebellar a.]</p>
<p>**<em>Vertebral</em> branches = PAP! (, <strong>A</strong>SA<strong>P</strong>SA, <strong>P</strong>ICA) -ANT Spinal a. -POST Spinal a. -POST inferior cerebellar a.</p>
<p>A: 80% of Strokes arise from occlusion in the \_\_\_\_ a. which is a bifurcated branch of the \_\_\_\_\_\_ Artery. What part of the brain is perfused by this bifurcated branch? B: What part of the Brain does the [POST cerebral a.] perfuse? [2]</p>
<p>80% of strokes<-----[middle cerebral a.] which is a bifurcated branch of INTERNAL CAROTID ARTERY. [middle cerebral a.] perfuses lateral cortex B: [POST cerebral a.] perfuses Occipital lobe & Temporal Lobes (memory lost)</p>
<p>A: The <em>Circle of Willis</em> Interconnects the \_\_\_\_ and \_\_\_\_ circulations. How does it do this exactly?</p>
<p>B: How is it related to perfusion of deep cerebral structures? (2)</p>
<p>C: What are the Anterior/Posterior<strong>Perforated Substance</strong>?</p>
<p>{Circle of Willis} Interconnects ANTERIOR and POSTERIOR circulations. It forms 1. [ANT communicating a.] between the two [ANT cerebral a.] and [POST communicating a.] between [Internal carotid] and [POST cerebral a.] ------------------------------------------------------------------------------------</p>
<p>B: As an Artery around brain base it gives rise to small perforating ganglion arteries via MCA--->[lenticulostriate a. ] = diencephalon / hypothalamus / telencephalon</p>
<p><span>C: </span><span>entry points of perforating a. on Brain Base</span></p>
<p>Blood Brain Barriers are formed by \_\_\_\_\_ \_\_\_ \_\_\_\_\_which use \_\_\_ junctions between \_\_\_\_ cells to filter blood coming from \_\_\_\_\_\_\_.</p>
<p>B: What are Pericyte? Where is it located (2)?</p>
<p>Blood Brain Barriers are formed by [ASTROCYTE GLIAL CELLS] which use TIGHT junctions between ENDOTHELIAL cells and [ENDOTHELIAL CELL LAMINA] to "gatekeep" blood coming from from CAPILLARIES(<em>which never make<strong>direct</strong>contact with brain tissue</em>)</p>
<p>B: Pleuripotent cell that gives rise to other blood vessels and regulates endothelial cells. Located [under basal lamina] but [ON TOP OF ENDOTHELIUM]</p>
<p>The Brain is \_\_\_% of Body weight BUT uses \_\_\_% Oxygen!</p>
<p>A: <em>metabolic</em>: INC neuronal activity--->\_\_\_\_\_\_\_\_ released --->[\_\_\_\_\_\_ \_\_\_\_\_\_\_ \_\_\_\_\_\_\_ activation]--->\_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_released at feet ---> applied to vessels to \_\_\_\_\_\_\_\_ \_\_\_\_\_\_\_\_ in that area</p>
<p>B: How is Control of Blood Flow <em>AUTOregulated</em>?</p>
<p>C: How is Control of Blood Flow regulated <em>neuronally</em>?</p>
<p>D: What is the normal Flow of Blood and what happens when that number is low? [2]</p>
<p>Brain is 2% Body Weight BUT uses 25% Oxygen! -Control of Blood Flow-</p>
<p>A: <em>metabolic</em>: INC neuronal activity--->Gluta<strong>mate</strong> released --->[astrocyte feet receptor activation]--->VasoDIOLATES factors released at feet ---> applied to vessels to DILATE VESSELS IN THAT AREA</p>
<p>B: <em>AUTOREGULATION</em>: Arterial & Smooth muscle cell mediated</p>
<p>C: <em>neuronally</em>: autonomic fibers innervate Cerebral vessels</p>
<p>D: Normally= [55 ml Blood/100 g in 1 minute]</p>
<p>20 ml = neurons stop electrically firing</p>
<p>10 ml = NECROSIS OF BRAIN!</p>
<p>Valveless Cerebral Veins ---(drain into)--->\_\_\_\_\_\_\_\_\_\_\_-----(drain into)-----> \_\_\_\_\_ \_\_\_\_\_\_ \_\_\_\_\_\_ + [Basilar Venous Plexus]</p>
<p>B: The [Basilar Venous Plexus] drains mostly \_\_\_\_ \_\_\_\_\_ and communicates with +\_\_\_\_\_\_\_\_\_\_\_\_\_</p>
<p>C: Where does the [Cerebellum and Brainstem] draiiin their veiiiinnns?</p>
<p>Valveless Cerebral Veins---(drain into)--->[DURA VENOUS SINUSES]----(drain into)----> [INTERNAL JUGULAR VEIN] + [Basilar Venous Plexus]</p>
<p>B: [Basilar Venous Plexus] mostly drains BASE OF BRAIN and communicates with [SPINAL CORD EPIDURAL VENOUS PLEXUS]</p>
<p>C: [Cerebellum and BrainSTEM] drain their veins into the [GREAT VEIN OF GALEN]! (along w/Deep Veins)</p>
<p>Describe the 2 Major Divisions of Cranial Venous Drainage -Superficial Veins (5) vs. Deep Veins (6)</p>
<p>****Superficial Veins*** 1. <em>Superficial</em> group = Dumps INto Superior/inferior Sagittal Sinuses 2. <em>Inferior</em> group= empties with transverse AND cavernous sinus ---->[SUP/inf sagittal sinus]----> **[SINUS CONFLUENCE]**---->Transverse sinuses--->IJV</p>
<p>vs.</p>
<p><em>Deep</em> Veins = empty into [Internal cerebral Veins] --->[GREAT VEIN OF GALEN]----->Straight Sinus---->**[SINUS CONFLUENCE]**----->Transverse sinuses ------>IJV</p>
Which radiographic scan would you typically use to identify hemorrhages? What color will the hemorrhage be?
CT SCANS (Where BONE & BLOOD ARE WHITE) ARE good with Hemorrhages! Hemorrhage will be WHITE AS WELL!
1) The Cranial Epidural Space contains what?
2) What’s special about this space?
1) Cranial Epidural “Space” contains Arterries and Veins
BUUT
2) There is NO Cranial Epidural Space physiologically
<p>What are<strong>Emissary Veins</strong>?</p>
<p>Vessels that connect [extracranial veins] to [Dural Sinuses]</p>
<p><em>What does the CT scan delineate?</em></p>
<p><strong>SubArachnoid Hemorrhage</strong> going into the Cisterns</p>
