Blood supply, hemorrhage and herniation

Question 1

what are the 4 parts of the Internal Carotid

Answer 1

Cervical part: bifurcation to carotid canal, anterior to transverse prcesses of upper 3 vertebrae

Petrous part: carotid canal in petrous part of temporal bone, upward and medially above foramen lacerum

Cavernous part: in the cavernous sinus, surrounded by sympathetic plexus, CN III, IV, VI, and V1

Cerebral part

Question 2

What is the internal carotid A going to supply

Answer 2

The anterior portion of the Brain and Eye

Question 3

What are the three parts of the Vertebral A

Answer 3

Cervical part: Transverse foramina of first 6 cervical vertebrae

Atlantic part: Perforates the dura and arachnoid, and passes through the foramen magnum

Intracranial part: In the cranium, unite at the caudal border of pons to form basilar artery

Question 4

Vertebral basilar Insuficiency

Answer 4

Reduced blood flow from the vertebral A

caused from hyperextension of the head or Extreme head rotation (Bowhunters syndrome)

Question 5

Subclavian steal syndrome

Answer 5

signs and symptoms that arise from retrograde (reversed) blood flow in the vertebral artery or the internal thoracic artery, due to a proximal stenosis (narrowing) and/or occlusion of the subclavian artery

this occurs proximal to where the Vertebral A comes off

Question 6

Aneurysms in what arteries affect this CN: V

Answer 6

Superior cerebellar A, abberant loops in this artery can cause tic douleroux

Question 7

Aneurysms in what arteries affect this CN: II

Answer 7

Internal carotid A

Anterior cerebral A

Anterior communicating A

Question 8

Aneurysms in what arteries affect this CN: III

Answer 8

Posterior cerebral A

Superior Cerebellar A

Posterior communicating A

Question 9

Aneurysms in what arteries affect this CN: VI

Answer 9

Labyrinthine A

Anterior Inferior Cerebellar A

Question 10

Aneurysms in what arteries affect this CN: VII

Answer 10

Anterior Inferior cerebellar A

Question 11

Is the Middle Cerebral A a part of the Circle of willis

Answer 11

No

Question 12

what is the significance of Border zones in the cerebral arteries

Answer 12

Areas in the brain that are between the locations of what arteries get what

therefore, it is susceptible to damage if there is sudden systematic hypotension or hypofusion

Question 13

What happens if their is no blood supply to the border zone between Anterior cerebral A and the Middle cerebral artery

Answer 13

Sensory and motor defects and laguage and behavioral problems

Question 14

What happens if their is no blood supply to the border zone between the Middle cerebral A and the Posterior Cerebral A

Answer 14

Visual and language problems

Question 15

What locations does the Anterior Cerebral A supply

Answer 15

Supplies most of the medial and superior surface of the frontal and parietal lobes

Question 16

What does the Middle Cerebral A supply

Answer 16

Supplies the lateral surface of frontal and parietal lobes and the superior part of the temporal lobe

Question 17

What does the Posterior Cerebral A supply

Answer 17

Supplies the occipital lobe and the inferior temporal lobe

Question 18

What are the 5 segments of the Anterior Cerebral A

Answer 18

Precommunicating segment: A1
-ICA to anterior communicating a

Infracallosal Segment: A2
-Anterior communicating a to where rostraum and genu of corpus callosum meet up

Precallosal Segment: A3

• Arches around the genu of corpus callosum, ends when vessels turn caudal
• Callosomarginal A

Supracallosal: A4

• Superior to corpus callosum
• Pericallosal A

Postcallosal: A5
-Caudal to corpus callosum

Question 19

What are the 4 segments of Middle Cerebral A

Answer 19

M1: Spenoid or horizontal segment
- ICA to the bifurcation at the insula

M2: Insular segment
-Bifucation at insula to circular sulcus of insula (right angle turn)

M3: Opercular segment
-Circular sulcus of insula to external surface of Lateral Fissure

M4: Cortical segment
-on the cortex

Question 20

What are the 4 segments of the Posterior Cerebral A

Answer 20

P1: Basilar bifurication to posterior communicating A

P2: Posterior communicating A to around the midbrain

P3: Quadrigeminal segment
-segment within the quadrigeminal cistern

P4: Cortical segment

• Parietooccipital artery
• Calcarine artery

Question 21

What are the main blood supplies to the medulla

Answer 21

Anterior spinal Artery: Caudal anterior and medial portions

Posterior spinal arteries: Caudal dorsal region

Vertebral artery: Caudal Anterolateral region

Posterior inferior cerebellar artery: Rostral dorsal lateral region

Anterior inferior cerebellar artery: posterior cochlear nucleus

Basilar artery: Rostral Medial and anterior region

Question 22

Specific things Anterior spinal artery supplies

Answer 22

Hypoglossal nucleus

Medial Lemniscus

Pyramid

Question 23

Specific things Posterior inferior cerebellar artery supply

Answer 23

Accessory cunate nucleus

solitary tract and nucleus

Spinal trigeminal tract

Spinal trigeminal nucleus

Inferior vestibular nucleus

Medial vestibular nucleus

Dorsal motor nucleus of vagus

Rubrospinal tract

Anterolateral system

Nucleus ambiguous

Question 24

Blood supply to the pons

Answer 24

All branches of Basilar A

Question 25

specific things Paramedian branches of basilar artery

Answer 25

Abducens nucleus Medial longitudinal fasiculus Abducens nerve Medial lemniscus Corticospinal fibers

Question 26

Specific things Long circumferential branches of basilar artery

Answer 26

Facial Nerve Mesencephalic nucleus and tract Spinal trigeminal tract and nucleus Facial motor nucleus Anterolateral system in the pons Trigeminal motor nucleus Principle sensory nucleus

Question 27

Specific things P1 segment of Posterior Cerebral A

Answer 27

Oculomotor nucleus Medial longitudinal fasciculus Red nucleus some of substantia nigra medial lemniscus

Question 28

intracerebral Hemorrhage

Answer 28

Subpial hemorrhagic stroke only in 2-3 percent of all head injuries source is usually the middle cerebral A

Question 29

What are causes of Herniation syndromes

Answer 29

``` Hemorrhage Mass/tumor Trauma Abscess Infection Metabolic conditions ```

Question 30

What are the divisions and compartments in the brain that play a role in herniation syndromes

Answer 30

Supratentorial compartment: above the tentorium and divided by a right and left by the falx cerebri Infratentorial compartment: Below the tentorium cerebelli Tentorial notch: continuation of the supra and infratentorial compartment

Question 31

Subfalcine Herniation

Answer 31

also called a cingulate or facine or falx herniation occurs in the supratentorial compartment and displaces brain tissue under the falx cerebri Can compress the Anterior Cerebral A which would affect the frontal and parietal lobe can evolve into a transtentorial herniation

Question 32

Transtentorial herniation

Answer 32

Also called a central herniation Brain is displaced downward toward the tentorial notch this will compress the brainstem, CN III and even lower structures -basilar artery and cerebral arteries Decorticate ridgity Decerebrate rigidity

Question 33

Uncal Herniation

Answer 33

Uncus and frequently portions of the parahippocampal gyrus are extruded over the edge of tentorium cerebelli and through the tentorial notch Impinge the midbrain Affects the cerebral peduncle and Oculomotor

Question 34

Tonsillar herniation

Answer 34

Cerebellar tonsils through the foramen magnum compression of the medulla and upper cervical spinal cord

Question 35

Blood supply to the internal capsule

Answer 35

Lenticulostriate arteries of the middle cerebral artery