Lecture 22: Vasculatur Neuroogy, Anatomy,, clinical syndromes and cerebral hemorrhage Flashcards
What are the two blood vessels responsible for entire arterial supply to the brain?
i. Internal carotid artery (straight shot up)
- goes into circle willis as the middle cerebral artery
ii. Vertebral Arteries: comes off subclavian artery, goes straight to the brain
- two vertebral arteries join and form basilar artery
Where does internal carotid artery enter skull? What are its branches? How does it terminate?
Enters at foramen lacerum
Has the following branches
i. ophthalmic artery (occlusion could lead to ipsilateral blindness)
ii. anterior choroidal artery (AChA)…no clinical significance
iii. Posterior communicating artery (joings anterior and posterior circulation)
ICA terminates as the
i. anterior cerebral artery (ACA)
ii. middle cerebral artery (MCA)
Where does vertebral artery originate? Where does it enter? What are its branches? Where do they terminate?
Originates from Subclavian Arteries
Enters at foramen magnum
Branches include
-anterior and posterior spinal arteries
-Posterior inferior cerebellar artery (PICA)
Terminates as BASILAR ARTERY (two vertebral arteries fuse to form basilar)
How are vertebral and ICA blood supply linked?
Via Posterior communicating artery (PComm)
What clinical feature would you get if you occlude Anterior Cerebral Artery (from ICA)? And on what side?
LEG weakness
Contralateral
What are major clinical features of Middle Cerebral Artery occlusion (from ICA)? Which side?
-Face and arm weakness (mebbe leg),
-sensory loss
-field cut (half of visual field gone)
-aphasia
-neglect
CONTRALATERAL for all symptoms
What are major clinical features of Posterior Cerebral Artery occlusion (from ICA)? Which side?
Field cut (visual) Contralateral
What is a hallmark of a brainstem vascular problem?
Crossed symptoms
-facial and arm weakness contralateral to one another
Crossed symptoms
-facial and arm weakness contralateral to one another
What is Weber Syndrome? What are the symptoms?
Medial midbrain syndrome
CN III ipsilatearl palsy and left hemiparesis (crossed signs)
MOA: occlusion of distal basilar artery and occlude the short circumferental branches of PCA and Basilar
What is Pontine/Locked in Syndrome?
Anterior pons wiped out
MOA: occlusion of basilar artery…loss of midbasilar artery = no blood supply to anterior pons
Known as “locked in” syndrome because they are awake but just can’t move
Symptoms: Contralateral hemiparesis or Quadruparesis/locked in syndrome, gaze palsy, facial palsy
What is Wallenberg/Lateral medullary syndrome?
Occlusion of Posterior inferior cerebellar artery (PICA) or contributing vertebral artery (VA)
Symptoms: right face and left body crossed sensory loss, right Horner’s, ataxia, vertigo, hiccups
Dysmetria
-cerebellum, vestibular nuclei, spinal trigeminal nuclei, nucleus ambiguous, spinothalamic and hypothalamic tract
Where do lacunar arteries (perforators) come from? What are major clinical features of lacunar occlusion (perforators)? Which side
Branches of middle cerebral artery
- contralateral motor or sensory deficit without cortical signs (so mentally sound)
- no aphasia, no confusion, no neglect, no apraxia…that’s what it means by no cortical signs
What symptoms do you get from cerebellar infarctin?
Ataxia, right dysmetria, vertigo, nausea/vomiting from the ataxia
Occlusion of PiCA, AiCA or SCA
What symptoms do you get from BA occlusion?
Locked in, ataxia, oculomotor deficits, crossed sensory/motor deficits
What symptoms do you get from VA occlusion?
- lower cranial nerve deficits (nucleus ambiguous)
- ataxia
- crossed sensory deficits
- Lateral Medullary Syndrome
What causes dysarthria?
Problem with articulation of speech Facial weakness Tongue weakness So it can be caused by MCA, ACA, PCA, VA and BA occlusions Not localizing
Where is the occlusion if you have sensory/motor deficits only?
Contralateral perforators
What are the two types of strokes?
i. ischemic strokes (80%)
ii. Hemorrhagic storke (20%)
What types of hemorrhagic stroke are there?
i. Intracerebral hemorrhage
ii. SubArachnoid hemorrhage
What are symptoms of subarachnoid hemorrhage:
worst headache of life
-with or without focal signs
-CT scan detects 95%
-lumbar puncture is required for 5% other
CSF is bloody or yellow (degradation of blood products
How do you figure out where the aneurysm is?
From an angiogram
Where are aneurysm typically located?
At branch points
AComm
PComm
Middle Cerebral Artery (MCA) bifurcation
What are treatment options for aneurysms?
- clipping or coiling of aneurysm
- nimodipine (calcium channel block) to reduce secondary neurological injury from vasopasm
- neurocritcal care
What is another cause of subarachnoid hemorrhages aside from aneurysms?
AVMs (arterial venous malformations)
-high pressure blood flow of artery will rupture the vein vasculature (which is not used to handling the high pressure
What is most common MOA of intracerebral hemorrhage? And where is the most common hemorrhage location?
Hypertension, hypertension, hypertension
-happens at small deep blood vessels (perforators) and at branch points
Charcot-Bouchard aneurysms
microscopic outpouching that occur at 90 degree arteriolar or small penetrating artery branch points
Cerebral amyloid angiopathy
A type of intracerebral hemorrhage that is NOT caused by high blood pressure
Where is R face/arm/leg weakness and headache localized?
A. Subarachnoid hemorrhage from L MCA aneurysm
B. ICH from L deep perforating arteries
C. left MCA ischemic stroke
D. Any of the above (answer)
How can you distinguish venous occlusion from arterial occlusion?
The former is slow progressing and the latter is acute presentation
