Cerebrovascular Flashcards
A localized increase in mean velocity from 50 to 150 cm/sec, at a depth of 50 mm with a TCD transducer placed in the temporal window probably indicates:
Significant stenosis of the (MCA) Middle Cerebral Artery
Conventional arteriography reveals 30% diameter stenosis in a symptomatic patient with severe stenosis by B-Mode and peak systolic velocities of 250 cm/sec in the proximal (ICA) Internal Carotid Artery, Which of the following statements about these findings is true?
A. the high velocities were cause by a cartid Kink
B. Even double projection arteriography may fail to determine the full extent of the diameter stenosis
C.Arteriography may fail to reval small”berry” aneurysms in the brain
D. B Mode “plaquein” may have been ultrasound noise
E. The ultrasound findings are not as important as the findings of an ARCH study
B. Even a double projection study may fail to determine the full extent of the diameter stenosis.
one of the advanages of a duplex is to be able
to visualize a cross section of an artery. Vessel overlap is a common problem. Vessel kink would show up in a artiography. “Backround ultrasound noise” would not cause accelerate velocities
All of the following are consistent with total occlusion of the (ICA) Internal Carotid Artery Except for the:
A. Abcence of flow in the ICA lumen
B. Decreased Velocity proximal to the occlusion
C. Retrograde flow in the distal ICA
D. Increase in flow through the collateral pathways.
E. Inability to be reconstructed surgically
C. Retrograde flow in the distal ICA
While the flow in the Segment of the Carotid artery distal to the new total occlusion conceivably could have eddy currents, it could not have purely retrograde flow, an important fact to remember is that, with rare exceptions,
occluded ICA’s may not be reconstructed by surgical means
Which of the following is a result of plaque ulceration?
A. Thrombus B. Intraplaque hemorrage C. Embolization D. All of the above E. None of the Above
D. All of the above
Ulceration of atherosclerotic plaque can be described as erosion of the intimal layer over the plaque surface. The erosion may progress to deep ulceration w/ embolization of plaque fragments. Thrombus formation is initiated by erosion of the plaque surface. Platelet aggregation
occurs, forming a thrombus directly over the ulceration. Distal embolization of the thrombus fragments may be a source of TIA’s. Intraplaque hemorrhage can occur as leakage of blood into the artheroscerotic plaque through the ulceration or by rupture of the Vasa Vasorum
During ordinary auscultation, of a Carotid Bifurcation, the detection of a Bruit that extends into diastole is:
A. Significant B. Marginally Significant C. Moderately Significant D. Highly Significant E. Impossible
D. Highly Significant
Bruits are not always a reliable indicator of
Disease, but a bruit that extends into diastole
is highly significant for carotid artery stenosis or for any artery location( Perhaps this is related to the fact that elevated end - diastolic velocities are suggestive of severe stenosis )
In an emergency room patient w/ stroke symptoms, the initial diagnostic exam of choice would be?
A. Carotid Duplex B. CT C.MRI D. Cerebral angiography E. Radionucleotide study
B. CT is usually the first exam of choice.
Since it can distinguish hemorragic stroke for ischemic infarction and is usually more readily available. It is also tolerated better because it is a much shorter exam. others may be used but CT is exam of 1st choice.
Which of the following is NOT a condition in which TCD might be useful?
A.Vasospasm following a subarachnoid hemorrhage B. Determination of brain death C. Cerebral monitoring during surgery D. Carotid Siphon Stenosis E. Temporal Arteritis
E. Temporal Arteritis
A 24 y o patient w/ history of recent MVA arrives in the ICU with symptoms of acute right sided weakness and aphagia. The most likely ideology for these symptoms is?
A. Carotid Dissection B. Cerebral aneurysm rupture C. Severe ICA stenosis D. Embolic activity from Cardiac mural thrombus E. Thyromocytopenia
A. Cardiac Dissection
Paresthesia refers to:
A. Dizziness B. Disturbance of speech C. Loss of function of a Limb D. Weakness E. Tingling sensation
E. Tingling sensation
A symptom of Vertebrobasilar insufficiency is?
A. unilateral paresis B. Aphasia C. Amaurosis Fugax D. Diplopia E. Non of the Above
D. Diplopia
Double vision is a symptom of vertebrobasilar
insufficiency.
Stenosis of the following vessel presents the high risk for TIA:
A. Left main Coronary artery B. Common Carotid Artery C. Internal Carotid Artery D. External Carotid Artery E. Middle cerebral Artery
C. ICA - Internal Carotid Artery
The most common treatment of acute ischemic Stroke constist of:
A. Aprin B. Dextran C. Heparin D. rtPA E. Dipyridamole
D. rtPA
Recumbinant tissue plasminogen activator (rtPA) is useful in improving outcomes only if administered within 3 hours of onset of symptoms
In TCD,the normal direction of flow of the MCA is:
A. toward the beam B. Away from the beam C. Biderectional D. Dependent on the Cardiac cycle E. Not detectable w/ TCD
A. Toward the beam
The best way to prepare the transducer for and intraopperative use is:
A. Autoclave it B. Emerse is cidex x 72 hrs C. Wash it w/ soap and water D. Place the transducer and acoustic gel with a sterile sleeve or bag. E.microwave it
D. place the transducer and gel with sterile sleeve or bag.
A decreased pulse at mid neck is suggestive of:
A. Carotid Aneurysm
B. Common Carotid stenosis if the contralateral pulse is normal.
C. Common Carotid stenosis of the contralateral pulse is decreased
D. Internal Carotid stenosis of the contralateral pulse is normal
E. Internal Carotid stenosis if the contralateral pulse is also decreased
B. CCA stenosis if the contralateral pulse is normal
Sometimes, however, the right neck pulse can feel reduced because of the larger mm overlying the carotid
A hemispheric stroke usually affects
A. The anterior cerebral artery distribution and the ipsilateral side of the body
B. The middle cerebellar artery distribution and the ipsilateral side of the body
C. The external carotid distribution, and may affect one or both sides of the body
D. The anterior cerebellar artery distribution and the contralateral side of the body
E. The middle cerebral artery distribution and the contralateral side of the body.
E. The middle cerebral artery distribution and the contralateral side of the body
TCD findings consent with vasospasm following subarachnoid hemorrhage would include:
A. Absence of diastolic flow in the middle cerebral artery
B. Greatly diminished diastolic flow in the middle cerebral artery
C. Reterograde flow in the middle cerebral artery.
D. Greatly increased mean velocities in the middle cerebral artery.
E. This is not a condition for which TCD is a useful modality
D. Greatly increase mean velocities in the middle cerebral artery.
Vasospasm causes greatly increased mean velocities in cerebral arteries.
Using the temporal window for TCD, you find a strong signal with considerable diastolic flow at a dept of 50 mm. This is most likely:
A. Anterior cerebral artery B. Posterior Cerebral artery C. Middle Cerebral artery D. Vertebral artery E. Basilar Artery
C. Middle Cerebral artery
The angel-correct cursor for velocity estimates the best:
A. Adjusted parallel with arterial walls
B. Adjusted perpendicular to arterial walls
C. Adjusted 0 degrees throughout for maximum frequency shift
D. Adjusted 60 degrees at all times regardless of vessel direction
E. Left off to avoid measurement errors
A. Adjusted parallel with arterial walls
On opthalmologic examination, a bright yellow spot is noted within a branch artery. This is a Hollenhorst plaque
True or False
True
These patients have a 75% risk of TIA or stroke over the next several years
Which of these conditions is least likely to cause a bruit in the neck
A. Severe stenosis of the internal carotid artery
B. Severe stenosis of the external carotid artery
C. Hyperdynamic carotid flows
D. Cardiac valvular disease
E. Critical preocclusive stenosis of the internal carotid artery
E. Critical preocclusive stenosis of the internal carotid artery
Bruits in the neck often disappear when the stenosis is very high -grade or preocclusive.
Amaurosis fugax related to an internal carotid lesion will cause:
A. Permanent blindness of the contralateral eye
B. Temporary blindness or shading of the ipsilateral eye
C. Permanent blindness of the ipsilateral eye
D. Temporary blindness or shading of the contralateral eye
D. Temporary blindness or shading of both eyes
B. Temporary blindness or shading of the ipsilateral eye
Amaurosis fugax affects the same side, Since thromboembolic activiity from ulcerated ipsilateral carotid atheroma is suspected.
When wave form is below baseline for a Vertebral artery. What is the significance?
the developing abnormal pressure gradient in the left arm is pulling flow below baseline at systole; the flow reverts to antegrade in diastole(referred to as a “to and fro” pattern in Zwiebel)
This might be converted to a full steal by performing reactive hyperemia on the left arm or having the patient exercise the arm to increase demand
With a subclavian s=artery stenosis on the right side;
A. The flow in the right vertebral artery will be reversed.
B. the patient will have right arm claudication.
C. the arm pressure will be reduced
D. The right axillary artery Doppler signal will be monophasic
E. None of the above will necessarily be present.
E. None of the above will necessarily be present
All of the answer choices are possible with right subclavian stenosis, but whether they actually occur depends on the severity of the stenosis
You perform percussion maneuvers on the superficial temporal artery and see oscillations on the spectral display. /the artery being insonated is most likely:
A. Internal Carotid Artery B. External carotid artery C. Vertebral artery D. Thyrocervical trunk E. A low - resistance artery
B. ECA
this percussion maneuver – the “temporal tap” must be used only cautiously to help identify the ECA in difficult situations. One report suggests that you can get pretty good oscillations in the ICA with temporal artery percussions in a large proportion of patients. It is better to differentate the ICA and ECA by evaluating wave forms characteristics, vessel positions, and the presence of branches.
Of the chief advantages of continuous-wave doppler, which of the following is false?
A. Aliasing cannot occur; recording of extremely high frequency shifts is possible,
B. It allows more precise range-gating than pulse-wave- Doppler
C. The signal - to - noise ratio is inherently greater than pulsed Doppler systems due to its continuous state of operation.
D. Continuous - wave Dopplers are less expensive
E. The instrumentation is less complex than in pulsed-wave Doppler
B. it allows more precise range-gating than pulsed-wave doppler
Continuous -wave doppler cannot range-gate: information is returned from along the entire beam.
One of the chief advantages of continous-wave doppler, which of the following FALSE?
A. Aliasing cannot occur; recording of extremely high frequency shifts is possible
B. It allows more precise range- gating than pulsed -wave Doppler
C. The signal- to noise ratio is inherently greater than pulsed doppler systems due to its continuous state of operation
D. Continuous - wave Dopplers are less expensive
E. The instrumentation is less complex than in pulsed- wave Doppler
B. It allows more precise range- gating than pulsed - wave Doppler
Continuous- wave doppler cannot range- gate; information is returned from along the entire beam.
The NASCET trial indicated that the best treatment for carotid stenosis in the symptomatic patient is:
A. Aspirin for stenosis greater than 70% in diameter reduction
B. Aspirin for stenosis greater than 7-% in area reduction
C. Carotid endarterectomy for stenosis greater than 70% diameter reduction
D. Carotid endarterectomy for stenosis greater than 70% in area reduction
E. Warfarin for stenosis less than 70% in diameter reduction
C. Carotid endarterectomy for stenosis greater than 70 % diameter reduction
Carotid surgery is recommended for symptomatic patients in this trial. NASCET is an abbreviation f=of North American Symptomatic Carotid Endarterectomy Trial. Other trial and studies of importance are the ACAS ( The Asymptomatic Carotid Atherosclerosis Study) And the ECET ( the European Carotid Endarterectomy Trial.)
Which of the following is NOT true regarding atherosclerosis?
A. Atherosclerosis starts a s breakdown of the intima .
B. Atherosclerosis usually develops at bifurcations
C. Atherosclerosis is a red blood cell disease
D. Atherosclerosis is a generalized disease
E. intimal damage/repair may begin in adolescence
C. Atherosclerosis is a a red flood cell disease.
Atherosclerosis is a generalized disease that begins most often at bifurcations due to the shear forces generated at the wall surfaces.
Patients with atherosclerosis in the periphery will have other atherosclerotic changes in the carotid and coronary vessels even though these may be clinically silent. Disruption of intimal continuity is the primary initial manifestation.
What information CANNOT be determined by cerebrovascular angiography?
A. Degree of narrowing of ICA By diameter
B. Presence of ulceration
C. Degree of narrowing of ICA by Cross- sectional area
D. Total occlusion of ICA
E. Crossover collateralization from the contralateral hemisphere
C. Degree of narrowing of ICA by cross-sectional area
Angiograms are longitudinal pictures of vessels; they cannot provide cross-sectional information
Magnetic resonance angiography(MRA) fucrtions by processing:
A. X- ray frequency shifts from moving blood
B. X-ray reflections from contrast material in the artery
C. Isotope radiation using a scintillation camera
D. Reflections from the hemoglobin in red blood cells
E. Radiofrequency pulsed created by tissue and blood flow
E. Radiofrequency pulses created by tissue and blood flow
MRI words by sending pulses of radio waves into tissue within a strong magnetic field. The resulting change of spin of the hydrogen protons create a signal that is then processed for image. Different processing methods (“time of flight” technique) can create images of blood flow; hence MR angiography or MRA.
A pitfall of MRA is?
A. Patients with cardiac pacemakers cannot be studied
B. It requires the use of ionizing radiation
C. It tends t overestimate the degree of stenosis
D. It requires a high degree of patient cooperation
E. A,C, and D
E. A, C, and D
MRA has become an accurate method for assessing carotid stenosis. Patients with pacemakers or other significant bodily metal cannot be subjected to the strong magnetic field this tes requires. MRA uses radio waves, not ionizing radiation(xrays). It does require the patient to lie quite still for a good while. Itr dowe tend to overestimate stenosis, while at least one study demonstrated that angiography often underestimates stenosis. Of course we duplex users are always right on the money
A binocular disturbance that disrupts vision in half the visual field of both eyes is called:
A. hemiplegia B. Amaurosis Duplex C. Dysphagia D. Homonymous hemianopia E. Hemiparises
D. Homonymous hemianopia
A patient relates a 10 - minute episode of loss of vision. He closed each eye and the reduction in the right half of his visual field was present bilaterally. This patient is describing amaurosis fugax ( True or False)
FALSE
Amaurosis Fugax is transient monocular blindness. This patient is describing HOMONYMOUS HEMIANOPIA
The doppler sample volume is usually adjusted:
A. Small, to sample flow only from center stream
B. Small, to sample flow right against the arterial wall
C. Beg enough to sample flow from the entire lumen of the artery
D. Big enough to sample flow from a long segment of the artery
E. Is not an issue with pulsed-wave doppler
A. Small, to sample flow only from center of stream
Cerebrovascular fibromuscular dysplasia occurs in:
A. Males B. Females C. Australians D. Infants E Hypoglycemics
B. Females
A right - handed patient experiences a 30 - minute episode of dysphagia. Which are of circulation is suspected?
A. Right hemisphere B. Left hemisphere C. Occipital cortes D. Verebrobasilar territory E. Brainstem
B. left hemisphere
The speech are of the cortes is in the temporal lobe of the dominant hemisphere
The Doppler diagnostic criterion that is most important for calling greater than 8- stenosis is:
A. Mean or time - average velocity B. Peak - systolic Velocity C. End - diastolic Velocity D. Minimum mid - diastolic average velocity E. Percent window reduction
C. End - diastolic velocity
This is the most widely used criterion, Although of course no number all by itself should determine an interpretation. Some investigators have had success with velocity ratrions ( ICA/ CCA systolic and /or diastolic ratios)
The first branch of the ICA is?
OPTHALMIC ARTERY
Advantages of angiography over duplex carotid studies include all EXCEPT”
A. Ability to visualize intracranial collaterals
B. Superiority at calling ulceration
C. Ability to visualize the entire cerebral vasulature
D. Unlimited repeatability
E. Ability to determine siphon stenosis
D. Unlimited Repeatability
A symptom of vertebrobasilar insufficiency is:
A. unilateral paresis B. Aphasia C. Amaurosis fugax D. Diplopia E. non of the above
D. Diplopia
diplopia - double vision
Which of the following is Not true regarding atherosclerosis?
A. Atherosclerosis starts as a breakdown of the intima
B. Atherosclerosis usually develops at bifurcations
C. Atherosclerosis is a red blood cell disease
D. Atherosclerosis is a generalized disease
E. intimal damage/repair may begin in adolescence
C. Atherosclerosis
Atherosclerosis is a generalized disease that begins most often at bifurcations due to the shear forces generated at the wall surfaces. Patients with atherosclerosis in the periphery will have other atherosclerotic changes in the carotid and coronary vessels even though these may be clinically silent. Disruption of the intimal continuity is the primary initial manifestation.
The Doppler diagnostic criterion that is most important for calling greater than 80 percent stenosis is:
A. Mean or time-average velocity B. Peak-systolic velocity C. End - diastolic velocity D. Minimum mid-diastolic average velocity E. percent window reduction
C. End - diastolic velocity
This sis the most widely used criterion, although of course no number all by itself should determine an interpretation. Some investigators have had success with velocity ratios (e.g ICA/CCA systolic and / or diastolic ratios)
why are brachial blood pressures obtained bilaterally when evaluating a patient for cerebrovascular disease?
A. The systolic components from each arm are averaged to determine the likelihood of cerebrovascular disease
B. It is necessary to know both brachial pressures to rule out the presence of hypo-perfusion syndrome
C. The brachial blood pressures are compared to see if they are equal
D. Both brachial blood pressures must be know to determine if hypertension is present
E. There is no value in obtaining bilateral brachial pressures if they are not compared to the ankle pressures.
C. The brachial blood pressures are compared to see if they are equal
If one pressure is 15-20 mmHg less than the other, subclavian steal is suspected on the side of the lower pressure
The TCD window used for assessing the opthalmic artery and carotid siphon is:
A. Temporal B. Suboccipital C. orbital D. Submandibular E. Nasal
C. Orbital
Which of the following is NOT considered a risk for atherosclerosis?
A. Hypertension B. Female Gender C. Diabetes Melitus D. Lipoprotein abnormalities E. Tobacco use
B. Female gender
Being female is not considered a risk factor, although postemenopausal females are at greataer risk for atherosclerosis than premenopoausal families. Indeed, male gender is considered a (minor) risk factor. Darn
