Chapter 8: Uncommon Pathology of the Carotid System Flashcards
a localized dilatation of the wall of an artery that involves all layers of the arterial wall
aneurysm
inflammation in the wall of an artery
arteritis
a benign mass at the carotid bifurcation (also called paraganglioma or chemodectoma) from the carotid body between the internal and external carotid arteries
carotid body tumor
a tear that starts at the inner layer of an artery and results in the splitting or separation of the walls of a blood vessel, creating an intramural hematoma and/or true and false lumens
dissection
an arteriopathy (neither atherosclerosis nor arteritis) that produces overgrowth in the arterial wall and is associated with stenosis, dissections, and aneurysms
fibromuscular dysplasia
the inner part of the vessel wall that is created by a dissection, normally the intima and part of the media. Typically, it produces into the lumen of the artery. Where there is a true and false lumen with flowing blood, the intimal flap lies between the two flowing portions and moves separate from the outer vessel during the cardiac cycle
intimal flap
an extravascular collection of moving blood from a localized rupture in an arterial wall or anastamosis that remains connected to the arterial lumen by a tract of flowing blood. Other terms are pulsating hematoma, expanding hematoma, and false aneurysm.
pseudoaneurysm
the quality of being tortuous, winding, or turning
tortuousity
white line within lumen; may be moving or stationary
aortic dissection
two clearly different flow patterns (true and false lumens) on each side of white ling
aortic dissection
intramural hemtoma, if visible, may cause smooth and tapered narrowing to stenosis to occlusion
dissection
elevated velocity in the narrowing if moderate to severe with downstream turbulence
dissection
section of artery at least 200% of normal ICA or 150% of normal CCA by some authors
aneurysm
widened area of artery with flow separation and/or partial thrombosis
aneurysm
vascular collection adjacent to artery past injury whether penetrating or iatrogenic; may have various levels of thrombosis or none
pseudoaneurysm
distint to and fro flow pattern in neck
pseudoaneurysm
irregular vessel wall; sometimes well-defined “string of beads” narrowing alternating with widening
fibromuscular dysplasia
doppler waveforms typically show a sudden change from normal ICA to elevated velocity and/or turbulent flow pattern in distal ICA
Fibromuscular dysplasia
thickened wall that may be patchy; echolucent “halo” around sections of superior thyroid artery
temporal arteritis
mass between ICA and ECA splays arteries apart; tumor may surround or encase artery if large
carotid body tumor
color aliasing seen frequently oweing to sharp angulation and/or higher velocities past curve; flow separation inside curve; velocities naturally increase as blood flows around a curve
tortuosity
most common pathology found during carotid exam
atherosclerosis
when length of vessel exceeds fixed distance between bifurcation and skull
tortuousity
What makes a sharp angle?
less than 30 degrees
m
more common angles in tortous vessel
30-90 degrees
Most affected vessel of tortuousity
ICA
pulsating mass in neck or present as a palpable pulsatile mass
tortuousity or kinking
velocity increases at ____ edge of curve in a tortuous vessel
outer
separation of the layers of an artery by a tear in the intima or an intramural hematoma from trauma and/or rupture of the vasa vasorum
arterial dissection
3 most common clinical situations of dissections
- extension into CCA from aortic dissection
- trauma of the ICA at or distal to angle of jaw
- underlying diseases in a vessel
One of the more common causes of stroke
ICA or vertebral dissection
Major mechanism of dissection
embolic
classic triad of ICA dissection
unilateral pain of head and neck
partial Horner syndrome
cerebral or retina ischemia
most common symptoms of dissection
headache
neck pain
When may a false positive dissection occur?
when duplication artifact from the wall of the jugular vein appears in CCA lumen
creates a reduced lumen that is smaller and not typically in same location as plaque
hematoma
high resistant ICA spectral waveform in absence of atherosclerotic plaque
dissection
nonatherosclerotic, noninflammatory disease in arterial wall
fibromuscular dysplasia
most common form of fibromuscular dysplasia
multifocal
characterized by multiple areas of narrowing and dilatations (“string of beads”)
multifocal FMd
typical location of FMD
mid/distal cervical ICA
Carotid bulb atypical FMD is often called;
carotid web
most common location of FMD
renal arteries
Second most common location of FMD
ICA
headache
whooshing sound in ears
neck pain
ringing in the ear
lightheadedness
FMD
first sonographic clue:
turbulence with or without high velocities in distal ICA after proximal ICA does not demonstrate atherosclerosis
FMD
located in adventitia of carotid bifurcation
carotid body tumor
typically benign tumor that forms from chemo-receptor cells
paraganglioma
small lump in anterior neck that had been growing slowly over a period of years
slight discomfort in area
dysphagia
pain
change in voice
Carotid body tumor
hypoechoic mass located between ICA and ECA at bifurcation, splaying two vessels apart
carotid body tumor
Highly vascularized mass from ECA
carotid body tumor
a dilatation of the artery that involves all 3 layers of arterial wall
aneurysm
Where are carotid artery aneurysms most commonly located?
CCA and ICA
main cause of carotid artery aneurysms.
atherosclerosis
nontender, pulsatile mass in neck
TIA
stroke
nerve compression
carotid aneurysm
also known as a false aneurysm
pseudoaneurysm
dilatation not covered by all layers of the vessel wall
pseudoaneurysm
typically caused by penetrating or blunt trauma or a deep dissection
pseudoaneurysm
channel connecting pseudoaneurysm to the feed artery
neck
usually present with a palpable pulsatile mass in neck associated with a history of trauma or carotid intervention; TIA or stroke
pseudoaneurysm
key feature of neck of pseudoaneurysm
to and from spectral Doppler flow pattern with rapid flow into the PA during systole and slow reversed flow throughout diastole
pulsatile color flow in mass with a yin-yang sign
pseudoaneurysm
caused by the use of therapeutic irradiation during treatment for various tumors of head and neck
radiation induced arterial injury
Site of RIAI
cca
atypical location of carotid lesion with history of radiation treatment in the past
RIAI
typically hypoechoic and do not contain calcifications
RIAI
inflammation of the artery wall that affects the arterial wall
arteritis
Two forms of cerebrovascular arteritis more commonly encountered
Takaysu arteritis
giant call (temporal) arteritis
4 vessels TA can affect
Aortic arch
brachiocephalic
carotid
subclavian
limb claudication
decreased blood pressure in arm
TIA
visual changes
stroke
arteritis
GCA commonly affects:
the elderly
4 vessels GCA can affect
aortic arch
carotid
axillary
superificial temportal artery
headache
jaw claudication
tenderness in temporal region
visual problems
elevated blood sedimentation rate
GCA
obstruction of arch from first to last in TA
subclavian
cca
aorta
renal arteries
long, smooth homogenous thickening of arterial wall
TA
GCA may affect branches of ECA to include:
facial
occipital
internal maxillary
superficial temporal artery
Normal intima-media thickness
less than 1mm
macaroni sign
TA
Thickening of STA and/or its branches
GCA
A pulsatile mass at the base of the neck may be indicative (and often mistaken) for an aneurysm, when it is most likely tortuosity from which of the following:
a. the proximal subclavian artery
b. the proximal vertebral artery
c. the proximal common carotid
d. the proximal internal jugular vein
c
Which of the following is NOT a characteristic of the flow in a secondary lumen created by a tear or dissection?
a. same direction of flow as in the true lumen
b. reverse direction of flow, exiting the false lumen through a secondary proximal tear
c. an alternate antergrade/retrograde flow patterin in and out of the false lumen
d. high velocities as would be seen in stenossis
d
What is a likely source of the symptoms in patients under 50 years of age presenting to the vascular lab with symptoms of stroke (without typical risk factors)?
disscetion of one of the carotid vessels
When performing Doppler on a tortuous internal carotid artery, how should the cursor be aligned if a velocity measurement must be made on a curved segmant of the artery?
set the angle cursor so the middle of the cursor is parallel to the walls and center stream
Which of the following is a major feature that should be present for a diagnosis of dissection?
a. a color pattern clearly showing two flow directions in the true lumen
b. identifiable thrombus within false lumen
c. atherosclerosis along the posterior wall
d. a hyperechoic (white/bright) line in the lumen of the artery
d
Which condition consists of a repetetive pattern of narrowing and small dilatation in an internal carotid artery, giving the appearance of a “string of beads”?
fibromuscular dysplasia
In a patient with hypertension, incidental diagnosis of fibromuscular dysplasia in the carotid artery system should lead to follow-up evaluation of which vessel?
renal arteries
Which of the following describes a vessel diameter measuring >200% of the diameter of a normal section of the ICA or >150% of the CCA?
a. true aneurysm of carotid vessels
b. large carotid bulb
c. normal carotid bulb
d. pseudoaneurysm
a
What is the distinguishing flow pattern in the neck of a pseudoaneurysm?
alternating, to and fro pattern
Why is it important to thoroughly evaluate the vessel wall of an artery where a perforation lead to a pseudoaneurysm?
thrombosis is likely to occur in that area
When is rad-induced arterial injury suspected?
The “plaque” is isolated and located in an atypical area
What are the major forms of arteritis found in the carotid system?
Takayasu’s disease and temporal arteritis
A 62 year old female patient presents to the vascular lab with a pulsatile mass in her neck and hoarseness in her voice. What would you suspect?
common carotid artery aneurysm
Why is it crucial to survey the entire length of the vessel when evaluating the superficial temporal artery for signs of temporal arteritis?
the inflamed area is not continuous
A 30 year old female patient presents to the vascular lab with decreased radial pulses and upper extremity claudication. What would you suspect?
Takayasy’s disease
A 65 year old female patient presents to the vascular lab with a history of headaches, tenderness in the temporal area, and jaw claudication. What would you suspect?
giant cell arteritis
A 25 year old male patient involved in competitive bicycle racing presents in the vascular lab with symptoms of headaches and subtle neurologic changes after a crash on the race course. What would you suspect?
spontaneous dissection
A 75 year old male patient with long-lasting history of COPD presents to the vascular lab for evaluation of his carotid arteries. An incidental mass is visualized at the carotid bifurcation on the right side, splaying the internal and external carotid arteries. What would you suspect?
carotid body tumor
You are asked to evaluate a pulsatile neck mass in an 80 year old female patient with recent placement of a central line in the right internal jugular vein. What would you suspect?
a pseudoaneurysm
A 50 year old male patient with history of non Hodgkins lymphoma treated with radiation presents in the vascular lab with some neurologic changes. What would you suspect?
radiation-induced arterial disease
Application of flow velocity criteria for the accurate evaluation of a tortuous internal carotid artery is difficult. It is therefore recommended that a combination of _____ imaging together with Doppler velocities to demonstrate the suspected area.
color
A dissection of an arterial wall may creat what is commonly referred to as a ____ lumen.
false
It is important to obtain a thorough medical or lifestyle history to evaluate for subtle trauma to the neck in patients presenting with ____.
stroke symptoms
With dissections that appear to be spontaneous, the primary risk factor is often _____.
hypertension
Fibromuscular dysplasia predominantly affects the ____ arteries.
renal
One of the best “tools” available on duplex ultrasound to clearly depict the “string of beads” appearance associated with fibromuscular dysplasia in the internal carotid artery is _____.
power Doppler
The Doppler spectrum in the arteries found within a carotid body tumor will typically display ___ resistance characteristics.
low
To avoid overestimating the diameter of a carotid artery aneurysm, measurements should be taken at the widest diameter in a ______ view along the axis of flow.
longtidunal
Penetrating trauma to the neck, presence of a bypass graft in the carotid system, or history of endarterectomy may (although rare) lead to the formation of ______.
pseudoaneurysmT
The area of highest narrowing seen with radiation-induced arterial injury tends to be at the _____ end of the stenotic area.
distal
A long, homogeneous narrowing typically seen in the subclavian artery of a young female patient would suggest _____.
Takayasu’s disease
In a transverse view, a “halo” surrounding the outer layer of the facial artery may suggest ____.
temporal artertitis
Two clearly different Doppler spectra seen when sampling on each side of a “white” line in an arterial lumen suggests ______.
dissection or intimal flap
The typical color-flow pattern within a pseudoaneurysm in a transverse view will demonstrate a(n) _____ appearance, with red on one half of the mass and blue on the other.
yin-yang
Inflammation of an artery, which may result in the breakdown of the structure of the arterial wall, is generally termed ____.
arteritis
Injury to the vasa vasorum, located in the media of the arterial wall and resulting in fibrosis of the portion of the wall, is the basis for lesions seen with ______.
radiation-induced arterial injury
Typically, nonmalignant paragangliomas of the neck are also called ______.
carotid body tumors
An abnormal growth of smooth muscle cells in the media of the internal carotid artery has been shown to be the underlying pathologic mechanism of _____.
fibromuscular dysplasia
It is believed that possibly one-fourth of the adult population present with some degree of ______ bilaterally, predominantly in the distal internal carotid arteries.
angulation
To ensure that velocity changes (particularly sudden increases) in a tortuous vessel are the result of a stenosis rather than sudden changes in the direction of flow, one should thoroughly examine the vessel in _____.
B-mode
The angle cursor is set ____ to vessel walls
parallel
_____ velcities distal to curves and kicnks are to be expected.
increased
separation of layers of an artery by a tear in the intimal or an intramural hematoma from trauma
dissection
Hallmark of an ICA dissection
intramural hematoma with luminal narrowing or occlusion of the true lumen
Dissections are often seen in one of three clinical situations:
extension into the CCA from an aortic dissection
trauma
other diseases
Spontaneous ICA dissections are offten associated with a history of _____.
hypertension
a nonatherosclerotic, noninflammatory disease; characterized by abnormal growth of smooth muscle cells and fibrous tissues in arterial walls
fibromuscular dysplasia
“string of beads”
fibromuscular dysplasia
most common location of FMD
renal arteries
second most common involved vessel FMD
ICA
most common symptom FMD
headache
1 to 1.5 mm structure in the adventitia of carotid bifurcation
carotid body tumor
Carotid body tumors are classified as _____.
paragangliomas
well-defined hypoechoic mass located between the ICA and ECA at the bifurcation
carotid body tumor
___ aneurysm involves all three arterial vessels.
true
perforation in arterial wall allowing blood to extravasate into surrounding tissue
pseudoaneurysm
“yin-yang flow pattern
pseudoaneurysm
injury to vessel wall from the therapeutic irradiation of various tumors of the head and neck
radiation-induced arterial injury
Stenosis can occur in __-__% of patients after external radiation
30-50
____ lesions do not typically contain calcifications and may have hypoechoic foci.
RIAI
iflammation of the artery wall
arteritis
two forms of arteritis
Takayasu’s
Temoral (giant cell)
arteritis that affects aortic arch and great vessels (brachiocephalic, carotid, subclavian)
Takayasu’s disease
affects medium and larger sized arteries; may includ aortic arch and carotid; typically affects the elderly
giant cell arteritis
claudication of arms
no radial pulsess
TIA and stroke symptoms
multiple bruits
Takaysayu’s disease
headaches
low-grade fever
jaw claudication
tenderness in temporal region
visual problems/blindness
temporal arteritis
______ may have a “halo” appearance surrounding the artery.
superficial temporal artery
Patients referred to the vascular laboratory for a carotid duplex examination are more likely to have which of the following conditions?
A. Arteritis
B. Carotid body tumor
C. Dissection
D. Tortuosity
D
A moving structure seen in the carotid lumen may be caused by all of the following conditions except:
A. Dissection
B. Arteritis
C. Venous valve refraction artifact
D. Acute thrombus
B
Which of the following conditions is described on imaging as a “string of beads”?
A. Fibromuscular dysplasia
B. Dissection
C. Radiation induced arterial injury
D. Intimal flap
A
Which of the following conditions is the most likely to be caused by blunt trauma?
a. carotid aneurysm
b. fibromuscular dysplasia
c. dissection
d. carotid body tumor
c
An 80 year old patient presents to the vascular laboratory with a pulsating lump just above the right clavicle. Which of the following conditions is the most likely cause for this palpable lump?
a. carotid body tumor
b. tortuous proximal carotid artery (CCA)
c. Radiation induced arterial injury
d. carotid aneurysm
b
Of the following locations in the carotid arteries, where is fibromuscular dysplasia most likely to occur?
a. ECA
b. proximal CCA
c. Proximal ICA
d. Distal ICA
d
Which of the following conditions results in a “false lumen”?
a. pseudoaneurysm
b. dissection
c. arteritis
d. fibromuscular dysplasia
b
Which of the following conditions is the most rarely encountered in the carotid arteries?
a. aneurysm
b. carotid body tumor
c. dissection
d. tortuosity
a
Which of the following is not a form of arteritis?
a. Takayasu’s
b. Giant cell
c. Temporal
d. Bernoulli’s
d
A to and fro Doppler signal in the “neck” of this mass is its important characteristic for diagnosis.
pseudoaneurysm
A renal artery examination may also be ordered for a patient who has which of the following conditions in the carotid arteries?
a. carotid aneurysm
b. fibromuscular dysplasia
c. dissection
d. radiation indicued arterial injury
b
Which of the following statemensts regarding tortuous carotid arteries is not true?
a. velocities increase around the outer wall of a curve
b. tortuous carotid arteries are typically asymptomatic but will sometimes cause symptoms of TIA or stroke
c. Color flow is the most helpful duplex tool to distinguish the course of a tortuous carotid artery
d. high velocities around the curve must be held to the same velocity criteria as straight carotid arteries
d
A 30 year old patient presents to the lab for a carotid examination with symptoms of right sided weakness and aphasia following a recentn automobile accident. Which of the followoing is the most likely etiology (cause) of these symptoms?
a. carotid body tumor
b. cerebral aneurysm rupture
c. severe atheroclerotic ICA stenosis
d. carotid dissection
d
A 65 year old woman presents to the vascular lab with no stroke symptoms, but has noticed a palpable lump in her mid-left neck. Which of the following conditions will you be considering as most likely in her carotid duplex examination?
a. aneurysm
b. fibromuscular dysplasia
c. carotid body tumor
d. pseudoaneurysm
c
A 75 year old patient presents to the vascular lab for a carotid duplex examminatoin complaining of sudden pain in the left neck. Which of the following is the most likely vascular condition that may account for this pain?
a. dissection
b. carotid kink
c. ICA occlusion
d. carotid body tumor
a
A heterogeneous mass is noted adjacent to the carotid artery demonstrating many red and blue vessels within it. A vessel is noted feeding the mass that demonstrates a low-resistance, low-velocity arterial signal. Which of the following choices is the least likely possible explanation for this mass?
a. pseudoaneurysm
b. lymph node
c. tumor
d. muscle
a
A patient presents to the vascular lab for a carotid duplex scan. The patient is known to have Takayasu’s arteritis. Which of the following procedures will be the least helpful in the assessment of this condition?
a. Look carefully for areas of carotid artery thickening in transverse and longitudinal views
b. obtain a Doppler waveform as proximally as possible in the brachiocephalic and left common carotid arteries
c. Obtain a Doppler waveform and diameter measurement of the distal ICA
d. Check bilateral blood pressures and subclavian Doppler waveforms
c
You have scanned a 45 year old patient with no evidence of atherosclerotic disease or significant obstruction in the carotid bifurcations, left subclavian, or vertebral arteries bilaterally. However, the right subclavian Doppler waveform is low resistance and a very long, smooth homogeneous stenosis is noted in the distal brachiocephalic artery extending into the proximal CCA where it tapers and ends. Which of the following is the most likely cause of this stenosis?
a. tumor compressing the brachiocephalic artery
b. dissection with an occluded false lumen
c. coarctation of the aorta
d. atherosclerosis
b
This structure characteristically splays the external and internal carotid arteries apart.
carotid body tumor
A patient has a small mass in the right distal neck with what appears to be a long branch or neck feeding the mass. The mass has been appearing to increase in size over months and has some subtle colors within it appearing interspersed with heterogeneous B-mode echoes in no particular pattern. The Doppler flow pattern in the vessel feeding the mass has a normal triphasic Doppler configuration. The patient has had no procedures or trauma. What is the most likely etiology of this mass?
tumor
