Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Vascular Ultrasound > Intracranial Cerebrovascular > Flashcards

Intracranial Cerebrovascular Flashcards

1
Q 
Which vessels can be insonated through the transtemporal window?
(A) MCA, ACA, PCA, tICA, ACoA, PCoA
(B) MCA, ACA, CS, ACoA, PCoA
(C) CS, OA, tICA, MCA
(D) VA, BA, PCA, PCoA, ACoA
A

(A) MCA, ACA, PCA, tICA, ACoA, and PCoA can all be insonated through the transtemporal window during a TCD examination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which of the following parameters can be used to identify an intracranial artery during a TCD examination?
(A) Peak systolic velocity
(B) Direction of blood flow at insonation depth
(C) Waveform shape
(D) Vessel diameter

A

(B) All of the cerebral arteries have average insonation depths, normal flow directions, and average mean flow velocities that can help identify each artery during a TCD examination. Only certain arteries can be visualized through each of the ultrasonic windows, which also helps to identify the arteries.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q 
What direction is the blood flow in the ophthalmic artery when it is being used as a collateral pathway from the external carotid artery to the internal carotid artery?
(A) Toward
(B) Away from
(C) Bidirectional
(D) Alternating
A

(B) The normal direction of flow in the ophthalmic artery through the transorbital approach is toward the probe as it provides blood flow to the eye. When the ophthalmic artery is providing collateral flow to the brain it will have a reversed flow direction which is away from the probe that is resting on the orbit through the transorbital approach.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which numbers for the middle cerebral artery are consistent with severe vasospasm?
(A) Mean Vel: > 180 cm/s and MCA/ICA: 3.0
(B) Mean Vel: > 180 cm/s and MCA/ICA: 4.0
(C) Mean Vel: > 200 cm/s and MCA/ICA: 3.0
(D) Mean Vel: > 200 cm/s and MCA/ICA: 6.0

A

(D) A mean velocity > 200 cm/s and an MCA/ICA ≥ 6.0 are consistent with severe vasospasm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

While performing a TCD examination through the temporal windows on a patient with right-sided paralysis you obtain normal velocities throughout the left anterior cerebral artery and left posterior cerebral artery and are unable to obtain a good signal from the left middle cerebral artery. What is the most likely diagnosis?
(A) The patient has a focal stenosis of the left anterior cerebral artery
(B) The patient has collateral flow through the left anterior cerebral artery
(C) The patient has a left middle cerebral artery occlusion
(D) The patient does not have a good left temporal window

A

(C) Hemiparalysis is a lateralizing symptom that affects the contralateral side of the body. Right-sided paralysis would indicate that there is a problem with perfusion to the brain’s left hemisphere. When the anterior and posterior cerebral arteries are able to be insonated and the middle cerebral artery is not, this is suspicious for an MCA occlusion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

A focal increase in the mean velocity from 65 to 185 cm/s at a depth of 50 mm insonating through the transtemporal window is obtained. What is the most likely diagnosis?
(A) Hemodynamically significant stenosis of the anterior cerebral artery
(B) Severe vasospasm of the anterior cerebral artery
(C) Severe vasospasm of the middle cerebral artery
(D) Hemodynamically significant stenosis of the middle cerebral artery

A

(D) The average depth of the middle cerebral artery is 55 to 65 mm with an average mean velocity of 55 cm/s ± 12. A focal increase to 185 cm/s at a depth of 50 mm is consistent with a hemodynamically significant stenosis within the MCA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q 
Which of the following vessels can be insonated through the suboccipital window?
(A) Middle cerebral artery
(B) Posterior communicating artery
(C) Basilar artery
(D) Posterior cerebral artery
A

(C) Both of the vertebral arteries as well as the basilar artery can be insonated through the suboccipital window. The posterior cerebral arteries cannot be visualized through this window.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q 
The largest intracranial branch originating from the internal carotid artery is the
(A) Middle cerebral artery
(B) Ophthalmic artery
(C) Anterior cerebral artery
(D) Posterior cerebral artery
A

(A) The largest intracranial branch originating from the internal carotid artery is the middle cerebral artery.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q 
The basilar artery gives rise to which of the following arteries?
(A) Posterior communicating artery
(B) Vertebral arteries
(C) Internal carotid arteries
(D) Posterior cerebral arteries
A

(D) The basilar artery gives rise to the right and left posterior cerebral arteries.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q 
With the TCD probe placed on the transtemporal window angled posteriorly at a depth of 67 mm a waveform is obtained with a flow direction that is away from the probe with a mean flow velocity of 36 cm/s. Which vessel is most likely being insonated?
(A) M2 segment of the MCA
(B) P1 segment of the PCA
(C) P2 segment of the PCA
(D) M3 segment of the MCA
A

(C) The posterior cerebral artery can be insonated with the TCD probe angled posteriorly from the transtemporal window at an average depth of 60 to 70 mm with an average mean velocity of 39 cm/s ± 10. The P1 segment will have flow that is toward the probe while the P2 segment will have flow that is away from the probe.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q 
The angle of insonance during a TCD examination is assumed to be
(A) 60 degrees
(B) 90 degrees
(C) 45 degrees
(D) 0 degree
A

(D) The angle of insonance during a TCD examination is always assumed to be 0 degrees.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q 
Which of the following transcranial windows is used to obtain the extracranial ICA used to calculate the MCA/ICA ratio in patients with suspected vasospasm?
(A) Submandibular window
(B) Transtemporal window
(C) Suboccipital window
(D) Transorbital window
A

(A) The submandibular window is used to obtain the extracranial ICA velocity that is used to calculate the MCA/ICA ratio in patients with suspected vasospasm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which is the following is a sign of collateral flow through the anterior communicating artery that can exist when there is significant extracranial cerebrovascular disease?
(A) Reversed flow within the ACA on the ipsilateral side of the disease
(B) Increased velocities within the MCA on the ipsilateral side of the disease
(C) Decreased velocities within the ACA on the contralateral side of the disease
(D) Reversal of flow in the MCAs bilaterally

A

(A) When there is collateral flow through the anterior communicating artery in the presence of extracranial disease, the two main findings on TCD are a global increase in velocity within the ACA contralateral to the disease and reversed flow within the ACA ipsilateral to the disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Hyperemia is a typical response to patients being treated post subarachnoid hemorrhage that results in which of the following?
(A) Lower cerebral artery velocities
(B) Higher cerebral artery velocities
(C) No change to the cerebral artery velocities
(D) No flow within the cerebral arteries

A

(B) Hyperemia is a typical response to patients being treated post subarachnoid hemorrhage that results in elevated cerebral artery velocities.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Vasospasm is a common condition that occurs in patients with subarachnoid hemorrhage that typically occurs during which time period?
(A) 1 to 3 days following the subarachnoid hemorrhage
(B) 4 to 7 days following the subarachnoid hemorrhage
(C) 7 to 14 days following the subarachnoid hemorrhage
(D) 14 to 25 days following the subarachnoid hemorrhage

A

(C) It is rare for vasospasm to occur early after a subarachnoid hemorrhage. Typically the maximum degree of vasospasm occurs between 7 and 14 days post subarachnoid hemorrhage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q 
The posterior cerebral circulation is composed of which of the following vessels?
(A) Posterior cerebral arteries
(B) Middle cerebral arteries
(C) Anterior communicating artery
(D) Terminal ICA
A

(A) The vertebral arteries join intracranially to form the basilar artery that bifurcates into the posterior cerebral arteries. These vessels are components of the posterior cerebral circulation.

17
Q

The internal carotid artery bifurcates intracranially into which two vessels?
(A) Middle and anterior cerebral arteries
(B) Middle and posterior cerebral arteries
(C) Anterior and posterior cerebral arteries
(D) Anterior and posterior communicating arteries

A

(A) The internal carotid artery bifurcates intracranially into the middle cerebral and anterior cerebral arteries.

18
Q

Which of the following transducers can be used to perform transcranial examinations?
(A) High-frequency pulsed-wave transducer
(B) Low-frequency pulsed-wave transducer
(C) Low-frequency continuous wave transducer
(D) High-frequency linear array transducer

A

(B) A low-frequency transducer using high power is needed for TCD examinations. A pulsed-wave transducer is used for traditional TCD.

19
Q 
With the TCD probe placed on suboccipital window a vessel is insonated at a depth of 90 mm with an average mean flow velocity of 50 cm/s. Which vessel does this most likely represent?
(A) Basilar artery
(B) Vertebral artery
(C) Posterior cerebral artery
(D) Posterior communicating artery
A

(A) The basilar artery can be insonated from the suboccipital window at an average depth of 89 to 90 mm with an average mean velocity of 41 cm/s ± 10 with flow going away from the probe.

20
Q 
The most reliable way to distinguish the difference between hyperemia and vasospasm is with the use of which parameter?
(A) Peak systolic velocity
(B) Time-average mean velocity
(C) MCA/ICA ratio
(D) End-diastolic velocity
A

(C) MCA/ICA ratio is the most reliable way to distinguish between hyperemia and vasospasm in patients with subarachnoid hemorrhage.

21
Q

Which of the following is TRUE about blind transcranial Doppler examinations?
(A) All patients have visibility through the transtemporal window
(B) The suboccipital window allows visualization of the PCAs
(C) It may be possible to obtain flow information from the contralateral transtemporal window
(D) High acoustic power levels should be used when insonating the ophthalmic arteries due to the depth of the vessels

A

(C) Some patients have an inadequate transtemporal window. It may be possible to use the contralateral transtemporal window to complete the examination.

22
Q 
The MCA/ICA ratio that identifies the presence of vasospasm rather than just hyperemia is
(A) MCA/ICA ratio > 6
(B) MCA/ICA ratio > 2
(C) MCA/ICA ratio > 4
(D) MCA/ICA ratio > 3
A

(D) An MCA/ICA ratio >3 indicates vasospasm over hyperemia.

23
Q

During a TCD examination all of the below findings are consistent with a hemodynamically significant stenosis EXCEPT
(A) A focal increase in velocity
(B) Global increase in mean flow velocity
(C) Velocity drop distal to elevated velocity
(D) Localized turbulence

A

(B) All of the following are findings associated with a stenosis of the cerebral arteries except for a global increase in velocity which usually indicates hyperemia or collateralized flow.

24
Q

A patient with a left internal carotid artery occlusion returns to your laboratory for a TCD examination that is unremarkable with the exception of an elevated time-average mean velocity of 105 cm/s within the left posterior cerebral artery. What do these findings most likely suggest?
(A) A hemodynamically significant stenosis of the left posterior cerebral artery
(B) Collateral flow from the external carotid artery to the internal carotid artery
(C) Collateral crossover flow from the right cerebral hemisphere
(D) Collateral flow through the posterior communicating artery

A

(D) The main finding present on a TCD examination when there is collateral flow through the posterior communicating artery in the presence of extracranial disease is a global increase in velocity of the posterior cerebral artery on the ipsilateral side of the disease.

25
Q 
Which cerebral artery has the highest incidence of occlusion resulting in a cerebrovascular accident?
(A) Middle cerebral artery
(B) Anterior cerebral artery
(C) Posterior cerebral artery
(D) Basilar artery
A

(A) The middle cerebral artery has the highest incidence of occlusion resulting in a cerebrovascular accident.

Vascular Ultrasound (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions