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
The most common medical treatment of acute ischemic stroke consists of:
A. Aspirin B. Dexran C. Heparin D. rtPA E. Dipyridmole
D. rtPA
Recombinant tissue plasminogen activator (rtPA) is useful in improving outcomes only if administered within three hours of the onset of symptoms.
The incidence of new strokes per year is:
A. 150.000 B. 250,000 C. 500,000 D. 1,000,000 E. 2,600,000
C. 500,000
During ordinary auscultation of a carotid bifurcation, the detection of a bruit that extends into diastole is:
A. Insignificant 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 andy other arterial location. (Perhaps this is related to the fact that elevated end-diastolic velocities are suggestive of severe stenosis.
You perform TCD, insonating the left anterior cerebral artery. The flow is toward the beam. This finding suggests:
A. Ipsilateral carotid obstruction, with right - to - left collateralization
B. Contralateral carotid obstruciton, with left - right collateralization
C. Ipsilateral carotid obstruction, with posterior - to - anterior collateralization
D. Contralateral siphon Disease
E. Nothing of diagnostic significance
A. Ipsilateral carotid obstruction, with right - to - left collateralization
Flow in the ACA is normally away from the beam, so this is not normal. It suggests flow coming across from the other hemisphere via the anterior communication artery.
Which statement about subclavian steal is FALSE?
A. It occurs most commonly on the left side.
B. Most patients are asymptomatic
C. It results from severe stenosis or occlusion of the proximal vertebral artery.
D. Lower blood pressure is seen in the affected arm
E. All of these statements are false
C. It results from severe stenosis or occlusion of the proximal vertebral artery - Is false
All other statements are correct. In subclavian steal, a severe stenosis or occlusion is present in the PROXIMAL SUBCLAVIAN ARTERY. The flow is “stolen” from the contralateral vertebral artery by the way of the basilar artery. Although subclavian steals occur most frequently on the left side, they are seen on the right occasionally with obstruction of the proximal right subclavian or innominate artery . Most subclavian steals are asymptomatic.
Which is not true regarding carotid bruit?
A. Severe stenosis may cause a bruit
B. The absence of a bruit rules out significant stenosis
C. The presence of a bruit is significant
D. A cervical bruit might arise from stenosis of the external carotid artery
E. A bruit extending into diastole suggests severe stenosis
B. The absence of a bruit rules out significant stenosis
Bruits are caused by turbulent flow. Presence of a bruit is significant, since there is turbulent flow for some reason(not always stenosis). The absence of a bruit does not rule out stenosis, severe stenosis may not cause a bruit.
Which of the following is NOR a useful olor flow andjustment ina an effort to detect slow flow in a possibly occluded interna carotid artery?
A. increase color flow gain B increase color flow PRF C. Decrease color flow PRF D. Decrease color flow wall filter E. Decrease beam angle relative to the vessel
B. Increasing color flow PRF
increase PRF will make the color flow less sensitive to slow flow
A TIA of the right anterior hemisphere of the brain will likely affect:
A. The entire body B. The left side of the body C. The right side of the body D. The right side of the face E. The back of the head
B. The left side of the body
Transient ischemic attacks affect the side of the body opposite that of the ischemic hemisphere.
Which of the following is/are TRUE regarding the clinical detection of a bruit
A. A bruit is always an indication of disease.
B. It means that turbulent flow exists
C. It may be indicative of valvular dysfunction in the heart
D. It may be a normal finding in parts of some vessels and during periods of enhanced
E. B, C and D
B, C and D
B - it means that turbulent flow exists
C - It may be indicative of valvular dysfunction in the heart
D. It may be a normal finding in parts of some vessels and during periods of enhanced flow
WHERE DOES THE ICA TERMINATE?
AT THE ACA- ANTERIOR CEREBRAL ARTERY
WHAT ARE THE 8 MAJOR BRANCHES OF THE ECA?
SUPERIOR THYROID ASCENDING PHARYNGEAL LINGUAL FACIAL ARTERIES OCCIPITAL POSTERIOR OCULAR INTERNAL MAXILLARY SUPERFICIAL TEMPORAL ARTERIES
Which of the following statements best describes transient ischemic attack (TIA)? A. it resolves completely within 24 hrs B. it resolves completely within 48 hrs C. it resolves completely within 72 hrs D. It resolves completely within 72 hrs E. none of the above
A. It resolves completely within 24 hrs
Which of the following statements best describes a transient eschemic attack(TIA)?
A. it resolves completely within 24 hrs B. it resolves completely within 48 hrs C. it resolves completely within 72 hrs D. it results in a permanent neurological deficit E. non of the above
A IT RESOLVES COMPLETELY WITH 24 HOURS
Which of the following symptoms are consistent with atherosclerotic disease of the vessels supplying the anterior circulation?
A. syncope B. diplopia c. drop attacks d. aphasia e. all of the above
D. APHASIA
Which of the following statements about the NASCET trial are true?
A. Symptomatic patients with ICA stenosis greater than 50% diameter reduction should be treated surgically.
B. asymptomatic patients with ICA stenosis greater than 50% diameter reduction should be treated surgically
C. symptomatic patients with I stenosis greater than 70% diameter reduction should be treated surgically
D. Non of the above
C. SYMPTOMATIC PATIENTS WITH ICA STENOSES GREATER THAN 70% DIAMETER REDUCTION SHOULD BE TREATED SUDRGICALLY
Which of the following statements regarding compression of the common carotid arteries during periorbital Doppler examination are true?
A. Compression should be performed for a period of one to three heartbeats
B. Compression is performed over the carotid bifurcation
C. Compression of the CCA in a normal patient should result in an augmented peri orbital signal
D. A and B
E. B and C
A. COMPRESSION SHOULD BE PERFORMED FOR A PERIOD OF ONE TO THREE HEARTBEATS
- Which of the following could be considered ultrasound techniques used in the investigation of cerebrovascular disease?
A. Spectral analysis of the Doppler shifts resulting from blood moving across a stenosis.
B B- Mode plaque Characterization
C. Flow mapping of the carotid bifurcation in a patient with and audible supraclavicular bruit.
D. B and C
E. All of the techniques described in this question utilize ultrasound
Which of the following procedures would be the best method of investigating a patient with recurrent TIA's? A. CPA B. B-Mode imaging C. OPG D. Pulsed Doppler flow mapping E. all are equally effective
B-Mode imaging is the most suitable answer as HIGH RESOLUTION IMAGING MAIY DEFINE ULCERATIONS WHICH MAY RESULT IN MICROEMBOLI
Which of the following information can be derived by a supraorbital PPG? A. The presence of plaque ulceration B. the presence of absence of a murmur C. the severity of an ICA stenosis D. The presence of and ICA occlusion E. None of the above
D. SUPRAORBITAL PPG IDENTIFIES SIGNIFICANT DISEASE IN THE ICA INDIRECTLY.
Which of the following statements is/are incorrect regarding carotid bifurcation bruits?
A. An occluded ICA does not result in a clinically evident bruit.
B. Bruits from the ECA usually differ in quality from those in the ICA.
C. Bruits never originate for a kinked ICA
D. B and C
E. all are correct
C. RECALL THAT BRUITS RESULT FROM TURBULENT FLOW ( AND A REYNOLD’S NUMBER GREATER THAN 2000) AND A KINKED VESSEL MAY CONTRIBUTE TO TURBULENCE
The most valuable use of TCD is vascular lab would be:
A. To identify intracranial arterial malformations
B. To confirm brain death
C to confirm occlusion of the extra cranial ECA
D. tTo monitor the effect of medication on intracranial arterial vasospasm
E. To identify flow in the intracranial ICA if it is present.
E. the confirmation of even minimal ICA flow beyond a critical stenosis is usually sufficient grounds for surgery.
Which of the following non-invasive techniques are direct examinations?
A. Carotid Phonoangography B. Spectral analysis of the Doppler Shifted sounds C. OPG-G D. A AND B E. A, B AND C
D. CHOICES A AND B EXAMINE THE EXRACRANIAL CAROTID CIRCULATION DIRECTLY WHILE CHOICE C OBTAINS INFORMATION REGARDING ICA FLOW INDIRECTLY.
A patient suffering from a TIA of the left anterior hemisphere of the brain will most likely have symptoms affecting which side of the following?
A. the left side of the face B. the entire body C. the right sided of the body D. the left side of the body E. both eyes
C. when the carotid artery i s the source of the embouls, a tia of the l eft anterior hemisphere will cause contralateral hemipariesis (often with ipsilateral blindness if the ophthalmic artery also suffers an embolic event)
Which of the following would you expect to be the result of a significant ICA stenosis?
A. An increase in velocity in the post -stenotic segment
B. Post- stenotic turbulence
C. Externalization of the CCA spectral waveform
D. and abnormal ICA?CCA radio
E. All of the above
E. Recall that a significant stenosis results in a decreased in flow and pressure distal to the stenosis. Immediately within and after the stenosis, flow velocities will increase and a little further on, turbulence will result. The CCA spectral waveform will show signs of externalization(i.e a wave form typical of the ECA) when the ICA is occluded because it now supplies a high resistance vascular bed( the face and neck) The ICA/CCA ratio is elevated when a significant ICA disease is present. Therfore, a significant stenosis may result in all of the choices presented.
When a frequency spectrum obtained from the ICA has a peak of approximately 10,000 Hz (10kHz), which of the following are true?
A. there is a significant stenosis of the ICA
B. There is usually spectral broadending as well
C. THE diastolic component wil be increased aslo
D. all of the above
E. a and b
D. WHEN A 10KHZ FREQUENCY SHIFT IS IDENTIFIED ON SPECTRAL ANALYSIS, THE STENOSIS IS VERY SEVERE (I.E 80 -99%). MARKED SPECTRAL BROADENING AND INCREASED DIASTOLIC FLOW VELOCITIES WILL ALSO BE EVIDENT.
In order to perform the 2D analysis of the carotid artery, which of the following should be utilized?
A. A 5 MHz transducer B. A 7.5 MHz transducer C. a 10 MHz transducer D. the highest frequency transducer that will penetrate to the depth of the vessel under investigation E. a, b or c
D. The highest frequency transducer (i.e 10 MHz) will result in the best axial resolution, However if the patient is thik - necked, a 1- MHz probe is not suitable. Therefore, the best answer is D; the highest frequency transducer that will penetrate to the depth of the vessel to be investigated
A stenosis of the right subclavian artery will result in which of the following?
A. blue finger syndrome
B. flow reversal in the ipsilateral vertebral artery
C. a damped monophasic brachial artery waveform
D. finger pain
E. non of the above will necessarily occur
E. THE WORD “SIGNIFICANT” HAS NOT BEEN USED TO DESCRIBE THE SENOSIS IN THIS QUESTION, THERFORE NON OF THE SCENARIOS DESCRIBED WILL NECESSARILY RESULT. (ALTHOUGH SEVERAL COULD)
Changing the frequency of the doppler probe during a duplex examination of the arterial system will result in:
A. a different frequency shift being measured from identical sites in the vessel
B. identical frequency shifts being measured from identical sites in the vessel
C. aliasing of the Doppler signal obtained
D. A and C]E. B and C
A. THE FREQUENCY SHIFT MEASURED BY A DOPPLER INSTRUMENT VARIES DIRECTLY WITH THE FREQUENCY OF THE DOPPLER CRYSTAL.
Pulsed Doppler flow mapping of the carotid circulation is sensitive to stenoses:
A. > 40% and therefore very reliable for the diagnosis of occlusion of the ICA
B. < 40% and therefore very reliable for the diagnosis of occlusion of the internal carotid artery
C. < 50% and therefor fairly reliable for detecting internal carotid artery disease
D. > 50% and therefore farily reliable for detecting ICA Disease
E. non of the above
D. > 50% and therefore fairly reliable for detecting ICA disease
A subclavian steal should be suspected when:
A. there is diastolic flow reversal in the subclavian artery during doppler examination
B. there is diastolic flow reversal in the vertebral artery during Doppler examination
C. there is systolic flow deceleration in the vertebral artery during doppler examination
D. A and B
E. B and C
E. B and C there is diastolic flow reversal in the vertebral artery during doppler examination and there is a systolic flow deceleration in the vertebral artery during doppler exmination.
Assuming a Doppler angle of 50 , Peak Doppler shifted frequency of kHz using a 4.5 MHz transmitted Doppler frequency is consistent with:
A. A normal examination B. A significant stenosis C. A moderate stenosis D. a mild stenosis E. non of the above
B. Note that a 5kHz Doppler shift indicates a significant stenosis for both transmitted Doppler frequencies
Any process that results in the damage of the intimal lining of the internal carotid artery may result in:
A. Calcific plaque formation B. A stroke C. a cardiac embolus D. A and B E. A, B and C
D. A and B Calcific plaque formtion and a stroke
Patients with symptoms of recurrent drop attacks should:
A have a doppler examination of the extra cranial carotid areteries
B. Have a doppler exam of the vertebral arteries
C. have a bilateral brachial artery pressure measurements
D. A and B
E. B and C
E.B and C
Drop attaches are a symptom of vertebrobasilar insufficiency, which may be the result of subclavian steal syndrome. If so, retrograde or oscillatory flow may be identified in the vertebral artery during Doppler sampling. Brachial pressure measurements will show a > 20 mmHg difference in pressure if a subclavian steal is present
The statement “spectral analysis of the sounds dtected with a sensitive microphone “ best describes which of the following examinations?
A. Duplex carotid artery Doppler examination
B. Spectral analysis of the carotid Doppler signal
C. Carotid Phonoangiographic analysis of a carotid bruit
D. andy of the above
E. non of the above
C. Choices a and b are not correct because the question states that the spectral analysis is of a carotid bruit detected with a sensitive microphone, indication that the data was obtained during a CPA study, not a duplex examination of the carotid arteries.
A high grade ICA Stenosis may:
A. Result in an easily detectable bruit B. have no Bruit at all C. result in a bruit lasting throughout systole and diastole D. A and B E. A, B and C
E. A, B and C
Then normal ICA demonstrates:
A. a multi phasic signal that demonstrates flow throughout the cardiac cycle
B. A Monophasic low pitched sound with little diastolic flow
C. a multi phasic signal with considerable diastolic flow
D. a high pitched Mono phasic signal with considerable flow evident during diastole
E. a prominent systolic sound with continuous diastolic flow
D. A high pitched Monophasic signal with considerable flow evident during diastole
Real-time B-Mode imaging with gated Doppler might also be called:
A direct 2-D imaging B. Duplex scanning C. Spectral analysis D. Phonoangiography E.. An indirect test
B. Duplex scanning
A CCA Signal that returns to baseline is suspicious for:
A. A high grade ECA stenosis B. And ECA occlusion C. A normal Study D. An ICA Stenosis E. non of the above
D. and ICA Stenosis
An ECA occlusion would result in 100% of CCA flow supplying The ICA, which in turn supplies the low resistance vascular bed of the brain. There for, the CCA signal would not return to baseline, but show continuous flow in diastole. A CCA signal that returns to baseline is most suspicious of a significant ICA stenosis
The Gold standard for identifying and characterizing carotid Artery plaque is currently:
A. Carotid Doppler flow mapping
B. Carotid angiography
C. B-Mode imaging of the extracranial carotid circulation
D. spectral analysis of a carotid doppler signal
E. non of the above
C. B-Mode imaging of the extra cranial carotid circulation.
2-D imaging with ultrasound will identify plaque that does not narrow the lumen and would therefore be missed on a carotid arteriogram.
The ICA is usually:
A. Smaller and more anteriormedial than the ECA and is branchless
B. brancless, larger and more posterior than the ECA
C. larger and posterior than the ECA and gives rise to several visible branches
D. smaller and more posterior than the ECA with several branches
E. non of the above
B. branchless, larger and more posterior than the ECA
A well defined spectral envelope always indicates
A. and abscence of Carotid atherosclerotic disease
B. the RBC’s Being sampled are moving at a similar velicity
C. A relative absence of turbulence
D. A and B
E. B and C
E. A well defined spectral envelope simply implies that all RBC’s are moving at a similar velocity. This velocity may be quite abnormal, as occurs in a tight stenosis if the Doppler sample is placed within the stenosis where velocities are high, yet flow is relatively laminar. Turbulence does not become evident until the sample volume is placed a few centimeters distal to the stenosis, where maximum turbulence will be identified
Heterogeneous plaque is best described as:
A. plaque with uniform echotexture, but demonstrating irregular borders
B. complicated plaque containing calcium as well as areas with decreased echotexture
C. non uniform plaque echotexture, with areas of increased and decreased echogenicity
E. non of the above
C. non uniform plaque echotexture, with areas of increased and decreased echogenicity
Which of the following are considered predisposing risk factors for the development of cerebrovascular disease? A. hypertension B. diabetes mellitus C. pulmonary embouls D. a and b E. a, b and c
D. and and b
When compared with spectral analysis of a continuous wave Doppler signal, a pulsed Doppler signal may demonstrate:
A. a more defined “window” than that obtained from a CW signal
B. higher velocities than those obtained with CW Doppler
C. simultaneous arterial and venous flow patterns
D. a and B
E. A, B and C
A. a more defined “window” that that obtained from a CW signal
Remember that CW Doppler samples all velocities across the vessel, resulting in a broader spectrum of velocities on spectral analysis. Aslo, CW is capable of demonstrating much higher velocities, than pulsed Doppler, Finalyy, CW is more capable of showing arterial and venoius signals simultaneously as the region of sensitivity is much larger than the sample volume used in PW Doppler
Angiographic examination of the extracranial carotid circulation may be performed via:
A. A catheter placed in the aortic arch via the femoral artery
B. A catheter placed in the common carotid artery following translumbar puncture of the aorta
C. Direct puncture of the carotid artery
D. a and b
E A, B and C
E. a, b and c
Which of the following is/are not considered a limitation(s) of color Doppler imaging?
A. the pulse repetition frequency is much lower when imaging with color doppler
B. Color flow Doppler is angle independent
C. the color of flow within a vessel indicates mean flow velocity and is not corrected for Doppler angle
D. A and B
E. all of the above
B. Color flow Doppler is angle independent
T or F
Retrograde flow in the frontal artery during a periorbital Doppler examination is a normal finding/
False
During a periorbital Doppler examination, prior to compression, a normal patient demonstrates antegrade ( forward flow towards the Doppler transducer) when the periorbital arteries are examined. If flow is reversed in either the supraorbital or frontal arteries, there must be a significant ).50%) ipsilateral ICA stenosis or occlusion
The ICA/CCA ratio is considered a more accurate indicator of significant ICA disease that ICA peak systolic velocity alone
True,
More important than the peak velocity measured in these vessels is the ECA/CCA velocity ratio, In general, the ICA/CCA velocity ratio is one of the most reliable indicators of significant ICA disease. This is especially true in labs that use peak flow velocities alone to categorize percent stenosis.
Non hemispheric cerebrovascular symptoms usually originate from the vertebrobasilar territory.
True,
Many of the cerebrovascular symptoms can be classified as to the territory from which they originate. For instance, symptoms which are hemispheric are usually classified as carotid territory, while those that are non - hemispheric are often located in the vertebrobasilar territory.
Despite its insensitivity to ICA stenoses < 40%, Doppler flow mapping remains a valuable technique for detecting high grade ICA lesions.
False,
The major limitation of Doppler flow mapping is the lack of visual control of the angle of incidence of the Doppler beam. Whn acutely curved or kinked vessesl ar sent, may be a high incidence of false positives and false negative examinat
T or F
The exdtracranial carotid system is the only source of emboli which may result in a CVA.
False, the extracranial carotid system is not the only source of emboli. The heart may also give rise to free floating bodies which may result from cardiac vegetations or tumors(ie) myxomas) or thrombus that often results from myocardial infarction
A duplex carotid examination consists of 2D imaging as well as Doppler sampling of the carotid vessels.
True,
A duplex exam consists of direct 2D visualization of the carotid vesses as well as the acquisition of flow information
T or F
During a CPA examination, a pansystolic bruit is documented. This is consistent with a stenosis in the 70-85 range.
False
A bruit lasting throughout systole (pansystolic) is consistent w/ a moderate to sever (60 -75%)stenosis.
T or F
Rouleau formations contribute to turbulence in flowing blood by disturbing the normal flow patterns of singe re blood cells.
True
The term Rouleau Formation comes from the French word for a roll and is used to describe a stack of 3 to 10 or more erythrocytes, resembling a roll of coins. These formations contribute to turbulence in flowing blood by distrubing the normal flow patterns of single red blood cells, Rouleau formation is often the result of an increase in the patient’s plasma immunoglobulin.
T or F
Color flow Doppler is of value when identifying the common bile duct
True color doppler also allows for the rapid determination of normal anatomy based on flow. For example the portal triad consisting of and arter, vein and duct can be accurately differentiated by flow direction in the case of the artery and vein and lack of flow in the case of the bile duct
T or F
The ICA is the most frequent site of extra-cranial atherosclerosis and a common source of stroke
False,
Close, but not quite the correct answer. The Carotid bifurcation is the most frequent site of exztra-cranial atherosclerosis and a common source of stroke.
T or F
Angiography is considered superior to duplex examination of the carotid system with ultrasound
True,
Angiography is considered superior to duplex examination of the carotid system with ultrasound because the entire carotid artery can be imaged regardless of patient habitus. duplex examination is excellent for imaging the bifurcation of most patients, but falls short of angiography for imaging the proximal carotid artery and high internal carotid artery
T or F
The color information that appears on screen while imaging with color flow doppler is the peak frequency of the moving reflectors being sampled in the color box
False
The color information that appears on screen is the mean ( not the peak) frequency of the moving reflectors being sampled in multiple sample volumes with the color box.
T or F
When performing a CW Doppler examination of the carotid arteries, the change in pitch that is heard at the carotid bifurcation is due to the differing sizes of the ICA and ECA
True
The audible change in pitch is due to the change in size of the vessel as well as the difference in the vascular bed that each branch OF THE CAROTID ARTERY SUPPLIES.
T or F
Transcranial Doppler examination allows us to differentiate between a high grade non - visualized ICA stenosis and complete occlusion of the vessel
True
Transcranial Doppler examination allows us to determine if there is flow in and obstructed ICA at a level that is not accessible from the neck, in iother words, we can identify flow in the cranium that would not be evident with extra cranial approach
T or F
Aside from age, the greatest contributor to stroke is cigarette smoking
False,
Aside from age, the greatest contributor to stroke is uncontrolled hypertension. High blood pressure serves to accelerate the process of atherosclerosis, damaging arterial walls, leading to aneurysm and potential risk of rupture. Along with the potential for aneurysm formation, hypertension increases the risk of embolization because of the increased flow states and turbulence that often accompany high blood pressure.
T or F
The measurement of peak diastolic flow velocities within a stenotic ICA segment is a good indicator of the severity of disease.
True
Below 50% stenosis, only systolic flow velocities increase. Beyond 50%, diastolic flow velocities Also increase. The ratio of the systolic to diastolic flow velocities can be used as an indicator of the degree of stenosis. A systolic/diastolic ratio <3 in the area of stenosis suggests a 70-80% stenosis.
T or F
Asymptomatic patients with ICA stenosis > 70% diameter reduction should be treated surgically with endartectomy
True
While the North American symptomatic Carotid Endarterectomy Trial (NASCET) suggest that most symptomatic patients with high grade stenosis greater that 70% diameter reduction be treated surgically with endarterectomy, a second trial, the asymptomatic Carotid patients with high grade stenosis grater than 60% will benefit from carotid endarterectomy.
T or F
The ICA can reliably be differentiated from the ECA because it is the larger and more posteriorlateral vessel
False
Although the ICA is usually the larger and more posterior lateral vessel, this is not always the case. The ICA is always branchless, so this is the best method of differentiating it from the ECA
T or F
Where spectral broadening is and abnormal finding in and exrtracranial Doppler examination, it is the norm in transcranial doppler studies.
TRUE
When reviewing spectral analysis of intracranial blood flow during Transcranial Doppler examination, must rethink our expectations. Where “spectral broadening” is abnormal in an extracranial Doppler exam, it is the norm in TCD because of the tiny vessel size and frequent branching
T or F
Obesity is considered a major risk factor for the development of cerebrovascular disease.
False
Its a risk factor but not a major risk factor
major risk factors are uncontrolled Htn, DM
T or F
Doppler flow mapping is considered and indirect test
False
DIRECT TEST ARE DESCRIBED AS THOSE EXAMINATIONS THAT INVESTIGATE THE SITE OF THE DISEASE ITSELF, INCLUDING DOPPLER FLOW MAPPING.
T OR F
The temporal tap is a useful technique for identifying the ECA
True
In cases where the ICA IS STENOSED, CSING THE WAVE FORM TO BECOME OF HIGHER RESISTANCE (like ECA), and the vessels are flull of shadowing plaque, making the identification of branches with 2D difficult, it is helpful to perform a temporal tap to identify the ECA
T OR F
Your Patient describes a rexent visul disturbance as “ a shade being pulled over one eye” lasting a few minutes, This is consistent w/ a stroke
False
A stroke is defined as a permanent neurological deficit. your patient is describing a TIA, NOT A STROKE
T or F
An ICA peak systolic flow velocity of 3 m/sec, with end diastolic flow measured at 1.2 m/sec is consistent with a stenosis of >70% diameter reduction
True
T or F
Power Doppler is superior to color flow doppler because it is very sensitive to the presence of flow, as well as providing direction, speed and flow character information
False
Power Doppler is very sensitive to the presence of flow, but displays no direction, speed or flow character information and is Therefore not suitable for studies where this information is important
