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