Week 1 Flashcards
A critical stenosis is the narrowing of the arterial lumen resulting in a hemodynamically signification reduction in what 3 things?
Volume, pressure and flow
In the aorta, how much of the area (%) has to be encroached before there is a reduction in pressure and flow distally?
90%
In smaller vessels, how much of the area (%) has to be encroached before there is a reduction in pressure and flow?
70-90%
With a complete occlusion of the ICA, what sound is heard?
Thumping
During a stenosis, what sound is heard?
After the stenosis, what sort of sound is heard?
Whistle or high pitched
Garbled
What is the measurement for CIMT? (carotid intima media thickness)
N= <0.9mm
Slide 11 & 12 on wk1 carotid grading is pretty much all bolded but not good flashcard content
So look at that stuff
ok
Where do we sample when comparing the velocity in a stenosis?
Usually proximal, but can be wherever the velocity is the most normal (if there’s a stenosis in the proximal setting
The higher the ratio, the greater the stenosis. True or False
True
directly proportional
How much of a vessel needs to be stenosed for it to be considered critical?
(diameter reduction)
50-80%
Diameter reduction is comparable to _____ measurements in a stenosis.
PSV
What is the formula for percentage stenosis for diameter reduction?
1-(residual/original)x100
longitudinal view of a vessel is needed to obtain this measurement
Residual diameter is the segment distal to the stenosis. True or False
False— it is the area within the stenosis
Original is the normal measurement
Remember: hemodynamically significant lesions are those with _______ diameter reduction.
> 50%
What view is required to obtain an area reduction image? What formula is used?
Transverse
Same formula as diameter reduction
1- (residual/original) x 100
Remember: hemodynamically significant lesions are those with _______ area reduction.
> 75%
For a hemodynamically significant stenosis:
_______% diameter reduction
_______% area reduction
> 50% DR
>75% AR
_____ stenosis: deceleration spectral broadening with a peak systolic velocity (PSV) <125 cm/s
<15%
______ stenosis: pansystolic spectral broadening with a PSV <125 cm/s
16-49%
_______ stenosis: EDV >140 cm/s
80-99%
_____ stenosis: pansystolic spectral broadening with a PSV of >125 cm/s and end diastolic velocity (EDV) <110 cm/s
or ICA/CCA PSV ratio >2 but <4
50-69%
________ stenosis: pansystolic spectral broadening with PSV >270 cm/s or
EDV >110 cm/s or ICA/CCA PSV ratio >4
70-79%
____________: no flow; terminal thump
Complete occlusion
What is the ratio formula for calculating a hemodynamically significant stenosis?
Prox ICA PSV/ distal CCA PSV
What does the ratio of ICA/CCA have to exceed to be considered a hemodynamically significant stenosis?
2
Subtotal occlusion of ICA demonstrates what? (hint: it is a sign)
String sign
Also trickle flow
The PSV is the first component of the spectral waveform to reduce due to a stenosis. True or false
True
Bruit appears as what on Color Doppler? (hint: it is a sign)
Confetti
What did the one nut say while chasing the other nut
Imma cashew
Subclavian steal syndrome shows a decrease in pressure on what side? What is the waveform?
The side of the innominate/subclavian stenosis will have lower pressure (usually by 20-40mm/Hg)
Will have a damped/monophasci flow pattern
A TIA resolves within how many hours?
24
TIA affects which side of the body?
The opposite side, with the exception of amaurosis fugax (which affects the same side eye)
What does R.I.N.D. stand for?
Reversible Ischemic Neurological Deficit
What is R.I.N.D?
Neurological symptoms that completely resolve after >24hours
What is a CVA (cerebral vascular accident)?
Neurological symptoms that do not resolve and leave the patient with permanent deficit
Qu’est-ce que c’est amaurosis fugax?
Blindness affecting one eye. Usually described as a “shade being pulled over the eye”
Amaurosis fugax affects only a portion of the visual field. True or false
False– can be all, partial or simply blurred vision
Infarction of the _______ is the most common cause of stroke.
MCA (middle cerebral artery)
When the frontal lobe is injured, what does the patient experience?
Loss of movement (paralysis) Unable to focus Difficulty with language, can't get words out Mood swings Difficulty problem solving
When the parietal lobe is injured, what does the patient experience?
Difficulties with hand-eye coordination
Problems reading, writing and naming
Lack of awareness
When the occipital lobe is injured, what does the patient experience?
Defects in vision or blind spots
Blurred vision
Visual illusions/hallucinations
Difficulty reading & writing
When the temporal lobe is injured, what does the patient experience?
Difficulty understanding language and speaking (aphasia)
When the cerebellum is injured, what does the patient experience?
Difficulty coordinating fine movements Difficulty walking Tremors Dizziness (vertigo) Slurred speech
When the brainstem is injured, what does the patient experience?
Breathing, HR, & consciousness
Difficulty swallowing
Problems w/ balance & movement
Dizziness & nausea (vertigo)
When the MCA is affected, what are the signs and symptoms?
Dysphasia/Aphasia Contralateral hemiparesis/hemiplegia Confusion Behavioural changes Agitated delirium
When the ICA is affected, what are the signs and symptoms?
Contralateral weakness Numbness or paralysis Ipsilateral amaurosis fugax Aphasia Bruit Occasional alteration in level of consciousness
When the ACA is affected, what are the signs and symptoms?
Contralateral hemiparesis (esp. in lower extremity)
Incontinence
Loss of coordination
Impaired motor & sensory functions
When the PCA is affected, what are the signs and symptoms?
Dyslexia
Coma w/o paralysis
When the vertebrobasilar arteries are affected, what are the signs and symptoms?
Facial numbness Diplopia (double vision) Vertigo Dysphagia Amnesia Ataxia
When the anterior circulation is affected, what are the signs and symptoms?
*Unilateral* motor and sensory deficits Paresthesia- tingling or numbness *on one side* Dysphasia and or aphasia Monocular disturbances Behavioural abnormalities
When the posterior circulation is affected, what are the signs and symptoms?
*Bilateral* motor and sensory deficits Vertigo Ataxia (muscle incoordination) Bilateral visual field defects Bilateral paraesthesia Drop attack (falling to the ground without other symptoms)
What is an endarectomy?
This surgery removes the plaque and is done with a stenosis >70%
What are the non-surgical methods for treating carotid atherosclerosis?
Balloon angioplasty and atherectomy
There’s a risk of acute embolization secondary to these procedures
Aspirin/anticoagulants/platelet inhibitors
Carotid exams are always a bilateral exam. True or false
True
