Blood supply, hemorrhage and herniation Flashcards
what are the 4 parts of the Internal Carotid
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
What is the internal carotid A going to supply
The anterior portion of the Brain and Eye
What are the three parts of the Vertebral A
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
Vertebral basilar Insuficiency
Reduced blood flow from the vertebral A
caused from hyperextension of the head or Extreme head rotation (Bowhunters syndrome)
Subclavian steal syndrome
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
Aneurysms in what arteries affect this CN: V
Superior cerebellar A, abberant loops in this artery can cause tic douleroux
Aneurysms in what arteries affect this CN: II
Internal carotid A
Anterior cerebral A
Anterior communicating A
Aneurysms in what arteries affect this CN: III
Posterior cerebral A
Superior Cerebellar A
Posterior communicating A
Aneurysms in what arteries affect this CN: VI
Labyrinthine A
Anterior Inferior Cerebellar A
Aneurysms in what arteries affect this CN: VII
Anterior Inferior cerebellar A
Is the Middle Cerebral A a part of the Circle of willis
No
what is the significance of Border zones in the cerebral arteries
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
What happens if their is no blood supply to the border zone between Anterior cerebral A and the Middle cerebral artery
Sensory and motor defects and laguage and behavioral problems
What happens if their is no blood supply to the border zone between the Middle cerebral A and the Posterior Cerebral A
Visual and language problems
What locations does the Anterior Cerebral A supply
Supplies most of the medial and superior surface of the frontal and parietal lobes
What does the Middle Cerebral A supply
Supplies the lateral surface of frontal and parietal lobes and the superior part of the temporal lobe
What does the Posterior Cerebral A supply
Supplies the occipital lobe and the inferior temporal lobe
What are the 5 segments of the Anterior Cerebral A
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
What are the 4 segments of Middle Cerebral A
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
What are the 4 segments of the Posterior Cerebral A
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
What are the main blood supplies to the medulla
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
Specific things Anterior spinal artery supplies
Hypoglossal nucleus
Medial Lemniscus
Pyramid
Specific things Posterior inferior cerebellar artery supply
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
Blood supply to the pons
All branches of Basilar A
specific things Paramedian branches of basilar artery
Abducens nucleus
Medial longitudinal fasiculus
Abducens nerve
Medial lemniscus
Corticospinal fibers
Specific things Long circumferential branches of basilar artery
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
Specific things P1 segment of Posterior Cerebral A
Oculomotor nucleus
Medial longitudinal fasciculus
Red nucleus
some of substantia nigra
medial lemniscus
intracerebral Hemorrhage
Subpial hemorrhagic stroke
only in 2-3 percent of all head injuries
source is usually the middle cerebral A
What are causes of Herniation syndromes
Hemorrhage Mass/tumor Trauma Abscess Infection Metabolic conditions
What are the divisions and compartments in the brain that play a role in herniation syndromes
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
Subfalcine Herniation
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
Transtentorial herniation
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
Uncal Herniation
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
Tonsillar herniation
Cerebellar tonsils through the foramen magnum
compression of the medulla and upper cervical spinal cord
Blood supply to the internal capsule
Lenticulostriate arteries of the middle cerebral artery
