Extracranial Cerebrovascular Flashcards
The term hemiparesis means A. Paralysis on one side B. Weakness on one side C. Numbness on one side D. Spasm of voluntary muscle on one side
B. Hemiparesis is a neurological symptom that refers to unilateral weakness that occurs on the contralateral side of the body to the affected side of the brain.
All of the following may represent vertebrobasilar symptoms EXCEPT A. Bilateral paresthesia B. Vertigo C. Ataxia D. Amaurosis fugax
D. Bilateral paresthesia, vertigo, and ataxia are all symptoms that affect the body as a whole and therefore are related to the posterior circulation. Amaurosis fugax is a lateralizing symptom that is most commonly caused by emboli to the ophthalmic artery through the ipsilateral ICA.
A stroke can be defined as
A. A neurological event with symptoms lasting less than 24 hours
B. A neurological event with symptoms lasting longer than 24 hours
C. A neurological event caused by increased blood flow to the brain
D. A neurological event occurring with no symptoms
B. A stroke is defined as a neurological event lasting longer than 24 hours.
Which of the following would NOT produce increased velocities within a vessel?
A. Narrowing of a normal stented internal carotid artery
B. Enlarged segment of the vessel at the level of the carotid bulb
C. Intraluminal 50% to 69% diameter stenosis within the internal carotid artery
D. Intraluminal 70% to 99% diameter stenosis within the internal carotid artery
B. Any stenosis within a vessel will cause an increase in velocity. The normal narrowing that occurs when a stent is placed in a vessel will also cause an increase in velocity. The natural enlargement of a vessel at the area of the carotid bulb will create a helical-type flow pattern that does not have increased velocities.
All of the following may represent internal carotid artery symptoms EXCEPT A. Contralateral hemiparesis B. Aphasia C. Amaurosis fugax D. Ataxia
D. Ataxia is a neurological symptom that is defined as an unsteady gait and is associated with the posterior circulation.
Which of the following is considered the number one cause of stroke? A. Hypertension B. Smoking C. Diabetes mellitus D. Hyperlipidemia
A. According to the American Stroke Association (ASA) hypertension is the most important risk factor because it is the number one cause of stroke.
The first branch off the internal carotid artery is the A. Ophthalmic artery B. Superior thyroidal C. Supraorbital artery D. ICA does not have branches
A. The first branch off the internal carotid artery occurs intracranially and is the ophthalmic artery.
A transient ischemic attack A. Resolves within 24 hours B. Does not resolve within 24 hours C. Typically lasts longer than 1 hour D. Resolves within 72 hours
A. The symptoms of a TIA resolve within 24 hours. Typically they resolve within 30 minutes to an hour.
The optimal Doppler angle for the extracranial cerebrovascular arteries is which of the following?
A. 0-degree angle to the artery walls
B. 60- to 80-degree angle to the artery walls
C. 25- to 45-degree angle to the artery walls
D. 45- to 60-degree angle to the artery walls
D. The optimal Doppler angle for the extracranial carotid arteries is between 45 and 60 degrees allowing the angle to be parallel to the vessel walls.
The first branch of the thoracic aortic arch is the A. Right common carotid artery B. Left common carotid artery C. Brachiocephalic artery D. Left subclavian artery
C. The first branch arising from the aortic arch is the brachiocephalic artery. The brachiocephalic artery then bifurcates into the right subclavian and right common carotid arteries.
A normal internal carotid artery
A. Has a high-resistant spectral waveform
B. Has a low-resistant spectral waveform
C. Is the main source of blood supply to the middle and anterior portions of the brain
D. Both B and C
D. The internal carotid artery should have a low-resistant monophasic spectral waveform with flow throughout the cardiac cycle. It is also the main source of blood supply to the middle and anterior portions of the brain.
There is a significant amount of shadowing plaque overlying the proximal internal carotid artery. What is the best approach to overcome this?
A. Use a more posterior approach
B. Turn the acoustic power up
C. Use power Doppler instead of color Doppler
D. Nothing-plaque is like bone and attenuates sound
A. A more posterior approach may help if the plaque is mostly located on the anterior surface of the vessel. Turning up the power and using power (amplitude) Doppler will not help because plaque is very attenuating. Changing windows is the best approach.
A normal external carotid artery
A. Has less diastolic flow compared to the ICA
B. Has more diastolic flow compared to the ICA
C. Is the main source of blood supply to the posterior aspect of the brain
D. Both A and C
A. The external carotid artery should have less diastolic flow when compared to the ICA and does not provide blood flow to the brain under normal circumstances.
What type of waveform would you most likely expect to see in the distal internal carotid artery with a focal 80% to 99% stenosis at the proximal internal carotid artery? A. Triphasic waveform B. Tardus-parvus waveform C. Normal waveform D. Poststenotic turbulent waveform
B. The type of waveform commonly seen distal to a critical (80-99%) stenosis will have delayed rise to peak systolic and low velocities. This type of waveform is referred to as a tardus-parvus waveform.
Which of the following describes plaque that is uniform and mostly composed of lipids? A. Homogeneous plaque B. Heterogeneous plaque C. Ulcerated plaque D. Hemorrhagic plaque
A. Homogeneous plaque refers to plaque with uniform low-level echogenicity and is mostly composed of lipids.
The innominate artery gives rise to which two arteries?
A. Left common carotid and left subclavian arteries
B. Right common carotid and right subclavian arteries
C. Left and right common carotid arteries
D. Left and right subclavian arteries
B. The innominate artery originates from the thoracic aortic arch and then bifurcates into the right subclavian and common carotid arteries.
Which of the following lesions is most likely to cause a subclavian steal syndrome?
A. Innominate artery stenosis
B. Left proximal subclavian artery stenosis
C. Left distal subclavian artery stenosis
D. Both A and B
D. Both an innominate artery and proximal left subclavian artery stenosis are likely to cause a subclavian steal syndrome because they would be proximal to the origin of the vertebral arteries. A stenosis in the distal left subclavian artery would be past the origin of the vertebral artery thus not resulting in a steal.
In the cerebrovascular system, atherosclerosis occurs most commonly in the A. Proximal area of a bifurcation B. Middle cerebral artery C. Proximal common carotid artery D. Brachiocephalic artery
A. Atherosclerosis in the cerebrovascular system occurs most commonly at the area of the bifurcation and the first few centimeters of the ICA.
The most common cause of ischemic stroke is A. Occlusion of a carotid artery B. Emboli C. Hemorrhage D. Dissection of the carotid artery
B. Most ischemic strokes are caused by emboli that travel from another location in the body through the blood stream to one of the cerebral arteries resulting in occlusion.
A 75-year-old man is scheduled for a carotid duplex and presents with symptoms of complete loss of mobility in the left arm. In which vessel would you most likely find disease? A. Left internal carotid artery B. Left common carotid artery C. Right internal carotid artery D. Right vertebral artery
C. Complete loss of mobility on one side of the body is a lateralizing symptom that is associated with ICA disease and since the left side of the body is controlled by the right cerebral hemisphere the vessel that would most likely have disease would be the right ICA.
The term paresthesia refers to A. Vertigo B. Inability to speak C. Loss of muscular control D. Tingling sensation
D. Paresthesia is described as numbness, tingling, or loss of feeling.
A patient arrives in your laboratory for a carotid duplex examination. Your findings are that the patient has a markedly dampened waveform in the right CCA with a PSV of 24 cm/s with an EDV of 14 cm/s. The left CCA had a normal waveform with a PSV of 126 cm/s with a EDV of 30 cm/s. The right vertebral artery had retrograde flow and the left vertebral had antegrade flow. Based on all the information what is the most likely diagnosis?
A. There is a stenosis of the left CCA.
B. There is a stenosis of the right brachiocephalic artery.
C. There is a stenosis of the right proximal CCA.
D. There is a stenosis of the right proximal subclavian artery.
B. The brachiocephalic artery gives rise to the right subclavian and right CCA. A stenosis of the brachiocephalic artery would effect the flow of both the right subclavian artery as well as the right CCA. The reduced flow through to the right subclavian is what would cause the reversal of flow in the ipsilateral vertebral.
If a patient is experiencing vertigo, which vessel is most likely the cause of the symptoms? A. CCA B. ICA C. ECA D. Vertebral artery
D. Vertigo is a nonlateralizing symptom and is usually associated with vertebrobasilar disease.
A typical waveform in a CCA with an ipsilateral ICA occlusion may have A. Increased peak systolic velocity B. Decreased or no diastolic flow C. Increased diastolic velocity D. A low-resistance waveform
B. Normally the CCA has a moderate amount of diastolic flow because it is providing blood flow to both the ICA and ECA. When a distal occlusion occurs, the resistance to flow may increase resulting in a decrease of diastolic flow on the same side as the occlusion. It is common to see little to no diastolic flow in a CCA with an ipsilateral ICA occlusion.
