Cerebrovascular Flashcards
What does TIA stand for, and what is its time span?
Transient Ischemic Attack, < 24 hours.
What does RIND stand for, and what is its time span?
Reversible Ischemic Neurological Deficit, > 1 day and < 1 week
What does CVA stand for, and what is its time span?
Cerebrovascular Accident, permanent
List the three types of stroke.
Ischemic: most common; from thrombosis.
Embolic: from heart, neck, other.
Hemorrhagic: aneurysm, anticoaguation therapy, etc.
Define Lacunar stroke.
Occlusive lesion in small perforating vessel of the brain.
List four risk factors for stroke.
Smoking
Hypertension
Arrhythmia (especially A-fib)
High cholesterol
Are parasthesia, hemiparesis, aphasia, dysphasia, and dysarthria characteristic of a hemispheric (cerebral) problem, or a posterior (cerebellum) problem?
Hemispheric
Are visual problems such as amaurosis fugax and transient monocular blindness characteristic of a hemispheric (cerebral) problem, or a posterior (cerebellum) problem?
Hemispheric
Are drop attacks, ataxia, blackouts, vertigo, and syncope characteristic of a hemispheric (cerebral) problem, or a posterior (cerebellum) problem?
Posterior
Is diplopia (double vision) characteristic of a hemispheric (cerebral) problem, or a posterior (cerebellum) problem?
Posterior
List the great vessels which arise from the aortic arch, in order.
Innominate (brachiocephalic) artery
Left Common Carotid artery
Left Subclavian artery
What is the first branch of the Interior Carotid Artery?
Opthalmic artery
List the three segments of the ICA siphon, proximal to distal.
Parasellar
Genu
Supraclinoid
What is the most common variant of the great vessels coming from the aortic arch?
The Left CCA off of or sharing the origin of the innominate.
What are the two most common pre-Willision anastomoses?
ECA to STA
ECA to Facial
Opening of collateral pathways is dependent upon these four factors:
Pressure gradients
Shared capillary beds
Patient age - more likely with the young
Time factor - slow progression of stenosis allows time for collateral development
What are the two most common sites of Fibromuscular Dysplasia?
Renal arteries
Internal Carotid arteries
Is Fibromuscular Dysplasia more common in men or women?
Women (three time more common than in men)
List the four stages of atherosclerosis development.
Endothelial (intimal) injury
Inflammation - fatty streaks
Proliferation - smooth muscle cells & neovasculature; cap formation
Advanced - fibrosis, necrosis, cap rupture, embolism
List six risk factors for carotid dissection.
Female < 40 years old Hypertension FMD Blunt trauma to chest or neck Congenital defect such as Marfan's Chiropractic manipulation
List three symptoms of carotid dissection.
Neck pain on one side.
Headache or “ringing ears”.
Symptoms of CVA.
What are some causes of thromboemboli of cardiac origin?
A-fib
Recent MI
CHF
Valve disorder
What is the structure between the ECA and ICA at the bifurcation which controls blood pressure and pH, and may form a form a vascular tumor?
Carotid Body
A Subclavian Steal is most commonly found on which side of the body?
Left
What is the cause of a Subclavian Steal?
Stenosis or occlusion in the proximal subclavian (or the innominate on right side), causing reversed flow in the ipsilateral vertebral artery.
If Subclavian Steal is compounded by carotid disease causing neurological symptoms, what is this termed?
Subclavian Steal Syndrome
Resistance in a normal vertebral artery is:
Low
The vertebral artery waveform will progress through these three stages as a subclavian steal progresses:
Early systolic deceleration - “bunny rabbit” waveform
To/Fro, Pendular waveform
Retrograde - fully developed steal
What is the arm pressure differential criteria for assessing a subclavian steal?
≥ 20mmHg
A subclavian artery which is a recipient of a steal will have what waveform?
Monophasic (whereas normal is triphasic)
What is the percent stenosis with:
PSV > 125 cm/sec
EDV < 100 cm/sec
50-79%
What is the percent stenosis with:
PSV > 125 cm/sec
EDV > 100 cm/sec
80-99%
List four characteristic signs of occlusion as observed by duplex.
Resistant CCA flow with little or no diastolic flow
Thumping at start of occlusion
No flow detected in ICA
Compensatory flow in ipsilateral ECA
List three items needed to identify a vessel during Transcranial Doppler.
Window used
Depth & angle
Velocity
Which vessels may be insonated using the Transtemporal window?
MCA
ACA
PCA
Which vessels may be insonated using the Transorbital window?
Opthalmic artery
Siphon of ICA
Which vessels may be insonated using the Suboccipital window?
Vertebral arteries
Basilar artery
Which layer of the cranial bones cause the most attenuation and scatter?
Middle layer
MCA: window, depth, direction
Transtemporal, 30-60mm, toward
ACA: window, depth, direction
Transtemporal, 60-80mm, away
PCA: window, depth, direction
Transtemporal, 60-70mm, P1 toward, P2 away
tICA: window, depth, direction
Transtemporal, 55-65mm, towards
Opthalmic: window, depth, direction
Opthalmic, 40-60mm, towards
Carotid siphon: window, depth, direction
Opthalmic, 60-80mm, towards/away/bi
VA: window, depth, direction
Suboccipital, 60-90mm, Away
BA: window, depth, direction
Suboccipital, 80-120mm, Away
List the first three branches of the ECA, in order from proximal to distal.
Superior Thyroid artery
Lingual artery
Facial artery
Transient Monocular Blindness is also known as:
amaurosis fugax
Define hemiparesis
Weakness of one side
Formula for NASCET stenosis calculation?
stenosis diameter/ICA diameter distal to stenosis
NASCET criteria for endarterectomy?
> 70% diameter reduction
Define hemianopia.
Blindness in 1/2 of the visual field in one or both eyes. (Problem in MCA - anterior circulation.)
Define amaurosis fugax.
Transient blindness, shades pulled down. Unilateral (anterior circulation). Considered a TIA.
Define diplopia.
Double vision. (Posterior circulation problem.)
Define Hollenhorst plaque.
A cholesterol embolus that is seen in a blood vessel of the retina. May indicate increased stroke risk.
How many strokes are suffered each year?
500,000
What is the velocity criteria for MCA vasospasm?
> 200 cm/sec
Which Carotid artery normally has a prominent dicrotic notch? CCA, ECA, ICA?
ECA
