ARDMS Vascular Technology (VT) Exam — Questions and Answers

Question 1: Carotid body tumors (paragangliomas) at the bifurcation characteristically displace which two vessels on duplex ultrasound?

CCA and ECA are splayed apart
ICA and vertebral artery are displaced medially
ICA and ECA are splayed apart (lyre sign) (Correct answer)
CCA and vertebral artery are compressed together

Correct answer: ICA and ECA are splayed apart (lyre sign)

The 'lyre sign' describes widening of the angle between the ICA and ECA caused by a hypervascular carotid body tumor seated at the bifurcation.

Question 2: Which waveform characteristic is most consistent with a high-resistance peripheral arterial system at rest?

Monophasic forward flow throughout diastole
Triphasic waveform with reverse flow component (Correct answer)
Biphasic waveform with brief reverse flow
Continuous low-velocity forward flow

Correct answer: Triphasic waveform with reverse flow component

Normal resting peripheral arteries (e.g., femoral) show triphasic waveforms with a brief reversal in early diastole reflecting high peripheral resistance.

Question 3: Carotid artery stenting (CAS) post-procedure surveillance with duplex ultrasound uses different velocity thresholds than native vessel criteria because stents:

Increase wall compliance and decrease velocities
Have no effect on Doppler velocities
Only affect diastolic velocities
Reduce wall compliance and increase velocities, requiring higher threshold cutoffs (Correct answer)

Correct answer: Reduce wall compliance and increase velocities, requiring higher threshold cutoffs

Stents reduce arterial wall compliance and produce intrinsically higher peak velocities, necessitating higher PSV thresholds (e.g., >300-450 cm/s for ≥50% in-stent restenosis) compared to native vessel criteria.

Question 4: Which organization administers the RVT examination in the United States?

American Registry of Radiologic Technologists (ARRT)
Society for Vascular Ultrasound (SVU)
American College of Radiology (ACR)
American Registry for Diagnostic Medical Sonography (ARDMS) (Correct answer)

Correct answer: American Registry for Diagnostic Medical Sonography (ARDMS)

The ARDMS administers the RVT examination and issues the Registered Vascular Technologist credential.

Question 5: Which accreditation body specifically focuses on vascular testing laboratories and requires compliance with published testing protocols?

Intersocietal Accreditation Commission for Vascular Laboratories (ICAVL) (Correct answer)
College of American Pathologists (CAP)
American College of Radiology (ACR)
The Joint Commission (TJC)

Correct answer: Intersocietal Accreditation Commission for Vascular Laboratories (ICAVL)

ICAVL is the primary accrediting body dedicated to vascular laboratories and evaluates physician oversight, equipment quality, personnel qualifications, and testing protocols.

Question 6: Which of the following best defines a pseudoaneurysm (false aneurysm)?

Dilation involving all three layers of the arterial wall
An arteriovenous fistula with aneurysmal dilation
A contained hematoma communicating with the arterial lumen through a wall defect (Correct answer)
Concentric calcification of the arterial wall without dilation

Correct answer: A contained hematoma communicating with the arterial lumen through a wall defect

A pseudoaneurysm lacks the true arterial wall layers; it is a pulsatile hematoma communicating with the vessel through a neck.

Question 7: Which vessel is most commonly responsible for a watershed infarct between the MCA and ACA territories?

Vertebral artery occlusion
Internal carotid artery stenosis (Correct answer)
Posterior communicating artery aneurysm
Basilar artery thrombosis

Correct answer: Internal carotid artery stenosis

Severe ICA stenosis reduces perfusion pressure, making the border-zone watershed region between MCA and ACA territories vulnerable to ischemia.

Question 8: A patient presents with a pulsatile abdominal mass and a bruit. Duplex ultrasound shows an aortic diameter of 4.2 cm. According to standard guidelines, what is the recommended surveillance interval?

Immediate surgical referral
Every 6 months
Every 3 months
Every 12 months (Correct answer)

Correct answer: Every 12 months

AAAs between 4.0–4.9 cm are typically surveilled annually per most US guidelines (e.g., SVS).

Question 9: Self-assessment examinations (SAE) offered by SVU or ARDMS can satisfy CME requirements primarily because they are:

Free to all RVT holders
Mandated by federal law for diagnostic sonographers
Approved only for first-time renewal cycles
Accredited educational activities with documented learning outcomes (Correct answer)

Correct answer: Accredited educational activities with documented learning outcomes

SAEs qualify as CME because they are structured, accredited activities with verified learning objectives and post-test documentation.

Question 10: How does ARDMS verify that RVT candidates have the required clinical experience before taking the exam?

By contacting the candidate's state licensing board
Via a proctored skills demonstration at a testing center
By reviewing hospital payroll records
Through a physician-signed attestation form submitted with the application (Correct answer)

Correct answer: Through a physician-signed attestation form submitted with the application

Candidates must submit a physician-signed attestation form documenting their clinical experience as part of the ARDMS application process.

Question 11: When documenting an accreditation-required quality improvement (QI) project, which element is mandatory for ICAVL compliance?

Evidence of action taken based on findings and outcome reassessment (Correct answer)
Monthly staff performance reviews
Annual equipment replacement schedule
Physician re-read rate of greater than 25%

Correct answer: Evidence of action taken based on findings and outcome reassessment

ICAVL requires that QI projects demonstrate a complete cycle: identifying the problem, implementing a change, and reassessing outcomes to confirm improvement.

Question 12: According to the widely accepted SRU (Society of Radiologists in Ultrasound) consensus criteria for grading internal carotid artery stenosis, which of the following findings is most consistent with a stenosis of 70% or greater?

ICA/CCA PSV ratio of 1.5
End-Diastolic Velocity (EDV) of 30 cm/s
Peak Systolic Velocity (PSV) of 125 cm/s
Peak Systolic Velocity (PSV) greater than 230 cm/s (Correct answer)

Correct answer: Peak Systolic Velocity (PSV) greater than 230 cm/s

The SRU consensus criteria use a Peak Systolic Velocity (PSV) of greater than 230 cm/s as a primary parameter to diagnose an internal carotid artery stenosis of 70% or greater, up to near occlusion. Additional parameters like an End-Diastolic Velocity (EDV) >100 cm/s and an ICA/CCA PSV ratio >4.0 are also used to confirm high-grade stenosis.

Question 13: An RVT who completes a structured journal club review of three peer-reviewed vascular ultrasound articles with documented discussion may potentially claim credit under:

Employer-mandated training credits
Patient safety hours
Self-directed learning or enduring materials CME (Correct answer)
Academic degree program credits

Correct answer: Self-directed learning or enduring materials CME

Structured journal clubs reviewing peer-reviewed literature can qualify as self-directed learning CME when properly documented.

Question 14: Which condition causes bilateral vertebral artery flow reversal and is associated with syncope or posterior circulation TIA symptoms triggered by arm exercise?

Bilateral vertebral artery stenosis
Bilateral vertebral artery dissection
Basilar artery occlusion
Bilateral subclavian steal syndrome (Correct answer)

Correct answer: Bilateral subclavian steal syndrome

Bilateral subclavian steal causes bilateral retrograde vertebral flow as both upper extremities steal from the posterior circulation during exercise, precipitating symptoms.

Question 15: After endovenous laser ablation (EVLA) of the great saphenous vein, which duplex finding at 1 week indicates a successful procedure?

Partial recanalization with turbulent flow
Unchanged GSV diameter with reduced flow velocity
Residual flow with reduced diameter
Closure of the GSV with absence of flow and echogenic occlusive thrombus within the treated segment (Correct answer)

Correct answer: Closure of the GSV with absence of flow and echogenic occlusive thrombus within the treated segment

Successful EVLA results in GSV occlusion demonstrated by absence of color flow and an echogenic thrombus filling the treated lumen.

Question 16: Which Doppler waveform characteristic indicates normal venous patency in the common femoral vein?

Continuous non-phasic flow
Spontaneous phasic flow varying with respiration (Correct answer)
High-resistance triphasic arterial pattern
Absence of flow at rest with augmentation only

Correct answer: Spontaneous phasic flow varying with respiration

Normal femoral vein flow is spontaneous, phasic with respiration, and augments with distal compression.

Question 17: Which criterion is most commonly used to recommend surgical or endovascular repair of an infrarenal AAA in a male patient?

Diameter ≥ 6.0 cm in any patient
Diameter ≥ 3.0 cm with thrombus present
Diameter ≥ 5.5 cm or growth > 10 mm/year (Correct answer)
Diameter ≥ 4.0 cm or growth > 3 mm/year

Correct answer: Diameter ≥ 5.5 cm or growth > 10 mm/year

Standard US guidelines recommend repair for AAAs ≥ 5.5 cm diameter in men or rapid growth > 10 mm per year due to rupture risk.

Question 18: Color Doppler aliasing at a vessel with high velocity can be corrected by:

Decreasing transmitted frequency
Decreasing the color gain
Increasing the pulse repetition frequency (Correct answer)
Increasing the Doppler angle to 90°

Correct answer: Increasing the pulse repetition frequency

Increasing the PRF raises the Nyquist limit, allowing higher velocities to be displayed without aliasing in color or spectral Doppler.

Question 19: During carotid duplex scanning, color aliasing within a stenotic segment indicates that the local flow velocity:

Has dropped below the Nyquist limit
Has exceeded the Nyquist limit (PRF/2) (Correct answer)
Represents venous contamination
Is bidirectional due to turbulence only

Correct answer: Has exceeded the Nyquist limit (PRF/2)

Color aliasing occurs when velocities exceed the Nyquist limit (half the pulse repetition frequency), causing color wrap-around and indicating high-velocity stenotic flow.

Question 20: The spectral broadening seen in disturbed flow distal to a stenosis is caused by:

A wide range of velocities across the vessel lumen (Correct answer)
Reduced wall filter settings
Increased laminar flow organization
Elevated peak systolic velocity only

Correct answer: A wide range of velocities across the vessel lumen

Turbulent and disturbed flow creates multiple velocity vectors simultaneously, filling in the normally clear spectral window below the waveform.

Question 21: Under HIPAA, which scenario represents a permissible disclosure of patient vascular study results without written authorization?

Transmitting images to a consulting physician for treatment purposes (Correct answer)
Sharing results with the patient's employer for an occupational health file
Discussing findings with the patient's family member without the patient's consent
Posting anonymized cases on social media for educational purposes

Correct answer: Transmitting images to a consulting physician for treatment purposes

HIPAA permits disclosure of protected health information (PHI) for treatment purposes, including sharing with consulting physicians directly involved in the patient's care.

Question 22: Which artifact appears as a bright echogenic line with posterior shadowing caused by total reflection at a gas interface?

Comet-tail artifact
Dirty shadowing (Correct answer)
Mirror image artifact
Clean shadowing

Correct answer: Dirty shadowing

Dirty shadowing (reverberation shadowing) occurs at gas interfaces where multiple reflections create a heterogeneous shadow with internal echoes.

Question 23: What is the preferred ultrasound-guided intervention for an iatrogenic femoral pseudoaneurysm that fails compression therapy?

Surgical ligation under general anesthesia
Balloon angioplasty of the puncture site
Elastic compression bandaging for 72 hours
Ultrasound-guided thrombin injection into the pseudoaneurysm sac (Correct answer)

Correct answer: Ultrasound-guided thrombin injection into the pseudoaneurysm sac

Ultrasound-guided thrombin injection is the first-line treatment for pseudoaneurysms that do not respond to compression. A small volume of thrombin (100–500 units) is injected directly into the sac under real-time imaging, inducing rapid thrombosis while the neck is monitored to prevent inadvertent arterial embolization.

Question 24: Which collateral pathway opens when the ipsilateral ICA is occluded and the contralateral ICA is patent?

Ophthalmic artery retrograde flow
Posterior communicating artery
Basilar artery-to-MCA anastomosis
Anterior communicating artery (Correct answer)

Correct answer: Anterior communicating artery

The anterior communicating artery connects the two ACAs, allowing contralateral ICA flow to supply the ipsilateral hemisphere via the ACoA.

Question 25: A patient with a femoral-popliteal vein bypass graft presents with calf pain. Duplex shows deep vein thrombosis (DVT) adjacent to the graft. Which additional graft-specific complication must be actively excluded?

Graft torsion
Native arterial occlusion proximal to the graft
Arteriovenous fistula formation
Perigraft infection with adjacent venous thrombosis secondary to inflammation (Correct answer)

Correct answer: Perigraft infection with adjacent venous thrombosis secondary to inflammation

Perigraft infection can present with adjacent DVT due to inflammatory thrombosis; this is a limb- and life-threatening complication that must be excluded in the clinical context.

Question 26: A 70-year-old male presents with sudden, severe 'tearing' chest pain radiating to his back. An abdominal ultrasound visualizes a linear, echogenic structure fluttering within the aortic lumen, separating it into two distinct channels. What is this classic finding called?

Intimal flap (Correct answer)
Mural thrombus
Reverberation artifact
Atherosclerotic plaque

Correct answer: Intimal flap

The clinical presentation is highly suggestive of an aortic dissection. The sonographic finding of a mobile, linear structure within the lumen that separates a true lumen from a false lumen is the characteristic intimal flap, which represents the torn intimal layer of the vessel wall.

Question 27: In a patient with suspected catheter-associated upper extremity DVT, which vein is most commonly affected?

Basilic vein
Brachial vein
Axillary or subclavian vein at catheter tip location (Correct answer)
Cephalic vein

Correct answer: Axillary or subclavian vein at catheter tip location

Central venous catheters most commonly cause thrombosis at or near the catheter tip, typically in the axillary or subclavian vein.

Question 28: Which duplex ultrasound finding is most diagnostic of acute deep vein thrombosis (DVT)?

Non-compressibility of the vein lumen (Correct answer)
Absence of color flow in the vein
Loss of phasic flow with respiration
Increased echogenicity of the vessel wall

Correct answer: Non-compressibility of the vein lumen

Non-compressibility of the vein with probe pressure is the primary criterion for diagnosing DVT on duplex ultrasound.

Question 29: Which professional development activity most directly improves an RVT's competitive position when applying for senior-level positions?

Renewing a state driver's license
Publishing case studies or presenting research at SVU conferences (Correct answer)
Maintaining CPR certification only
Completing mandatory OSHA training

Correct answer: Publishing case studies or presenting research at SVU conferences

Publishing case studies or presenting at professional conferences demonstrates advanced expertise and commitment to the field, distinguishing candidates for senior roles.

Question 30: Which maneuver is most appropriate to assess venous reflux in the lower extremity during a duplex exam?

Elevation of the limb above heart level
Proximal limb compression
Distal limb compression and release (Correct answer)
Valsalva maneuver

Correct answer: Distal limb compression and release

Rapid release of distal manual compression or pneumatic cuff deflation generates retrograde flow to assess valve competence.

Question 31: Which hemodynamic principle states that flow rate equals the pressure gradient divided by resistance?

Laplace's law
Bernoulli's principle
Ohm's law analogy for blood flow (Correct answer)
Poiseuille's law

Correct answer: Ohm's law analogy for blood flow

The hydraulic analogy to Ohm's law describes blood flow (Q) as the pressure difference (ΔP) divided by vascular resistance (R).

Question 32: Visceral artery aneurysms of the splenic artery are most commonly associated with which clinical condition?

Marfan syndrome and bicuspid aortic valve
Portal hypertension and multiparity (Correct answer)
Hypertension and diabetes mellitus
Renal artery stenosis and smoking

Correct answer: Portal hypertension and multiparity

Splenic artery aneurysms are strongly associated with portal hypertension (increased splenic blood flow) and multiparity (hormonal/hemodynamic effects).

Question 33: A 40-year-old patient presents with post-prandial epigastric pain. During a mesenteric duplex exam, the celiac artery PSV is 140 cm/s during quiet inspiration. When the patient performs a deep expiration, the PSV increases sharply to 360 cm/s with associated post-stenotic turbulence. These findings are most characteristic of:

Atherosclerotic celiac artery stenosis.
Celiac artery dissection.
Median Arcuate Ligament Syndrome (MALS). (Correct answer)
Superior Mesenteric Artery (SMA) syndrome.

Correct answer: Median Arcuate Ligament Syndrome (MALS).

Median Arcuate Ligament Syndrome (MALS) is caused by extrinsic compression of the celiac artery by the median arcuate ligament of the diaphragm. This compression is most pronounced during expiration, leading to a significant, transient increase in velocity. The velocity normalizes or improves during inspiration as the diaphragm moves and relieves the compression. Atherosclerotic disease would not vary with respiration.

Question 34: A candidate reviewing the RVT content outline wants to understand which cerebrovascular topic carries the most weight. Which is it?

Transcranial Doppler
Intracranial venous evaluation
Carotid duplex imaging (Correct answer)
Vertebral artery evaluation

Correct answer: Carotid duplex imaging

Carotid duplex imaging carries the greatest weight within the cerebrovascular section of the RVT content outline.

Question 35: What is the significance of a 'blunted' or non-phasic Doppler waveform in the common femoral vein?

Indicates arteriovenous fistula
Caused by deep breathing technique
Normal variant in obese patients
Suggests proximal obstruction such as iliac vein DVT (Correct answer)

Correct answer: Suggests proximal obstruction such as iliac vein DVT

Loss of respiratory phasicity in the femoral vein suggests an obstruction proximal to the interrogation site, such as iliac vein thrombosis.

Question 36: Under the principle of universal precautions, how should vascular laboratory staff treat ALL patient blood and body fluids?

As requiring only standard gloves, with no additional PPE
As infectious only during invasive procedures
As non-infectious unless the patient tests positive for HIV or hepatitis
As potentially infectious regardless of the patient's known diagnosis (Correct answer)

Correct answer: As potentially infectious regardless of the patient's known diagnosis

Universal precautions mandate treating every patient's blood and body fluids as potentially infectious to protect staff from undiagnosed or unreported bloodborne pathogens.

Question 37: The range resolution (axial resolution) of a pulsed ultrasound system is primarily determined by:

Pulse repetition period
Transducer aperture size
Spatial pulse length (Correct answer)
Focal zone depth

Correct answer: Spatial pulse length

Axial resolution ≈ spatial pulse length / 2; shorter pulses (higher frequency, fewer cycles) improve the ability to distinguish two closely spaced reflectors along the beam axis.

Question 38: A patient undergoes carotid endarterectomy (CEA). Intraoperative TCD monitoring detects a sudden drop in MCA mean velocity to below 15 cm/s after cross-clamping. This indicates:

Hyperemic response to ischemia
Vasospasm from surgical manipulation
Successful shunting with normal perfusion restored
Cerebral hypoperfusion requiring shunt placement (Correct answer)

Correct answer: Cerebral hypoperfusion requiring shunt placement

An MCA mean velocity <15 cm/s or >50% drop from baseline after carotid cross-clamp indicates inadequate collateral flow and warrants intraoperative shunting.

Question 39: Which of the following clinical experience prerequisites is commonly required when applying for the RVT exam through the experience-based pathway?

Completion of two full-time years in radiology
A minimum number of documented vascular ultrasound examinations (Correct answer)
Board certification in internal medicine
500 cardiac ultrasound studies

Correct answer: A minimum number of documented vascular ultrasound examinations

Applicants using the experience pathway must document a specified minimum number of vascular ultrasound studies performed under physician supervision.

Question 40: In segmental limb pressure testing, what finding is characteristic of isolated popliteal artery disease?

Gradient between above-knee and below-knee segmental pressures with normal thigh pressures (Correct answer)
Symmetrically reduced pressures at all levels bilaterally
Gradient between brachial and proximal thigh pressures
Gradient between ankle and metatarsal pressures

Correct answer: Gradient between above-knee and below-knee segmental pressures with normal thigh pressures

Isolated popliteal disease produces a pressure drop between the above-knee and below-knee cuff levels with normal proximal thigh pressures, localizing disease to the popliteal segment.

Question 41: A peak systolic velocity ratio (stenotic/prestenotic) greater than 4.0 in the internal carotid artery typically indicates stenosis of:

Less than 50%
70–99% (Correct answer)
Near occlusion only
50–69%

Correct answer: 70–99%

A velocity ratio greater than 4.0 is a validated criterion for ≥70% ICA stenosis, corresponding to hemodynamically significant disease.

Question 42: Which of the following best describes the purpose of the ARDMS Continuous Quality Improvement (CQI) program for RVT holders?

To audit hospital vascular laboratory accreditation status
To encourage ongoing self-assessment and professional development beyond minimum CME (Correct answer)
To replace the CME requirement for experienced technologists
To certify new sonography graduates before sitting for the RVT exam

Correct answer: To encourage ongoing self-assessment and professional development beyond minimum CME

The CQI program promotes lifelong learning and professional growth beyond the baseline CME renewal requirements.

Question 43: In Ehlers-Danlos syndrome type IV (vascular type), which vessel is at greatest risk for spontaneous rupture?

Carotid siphon
Medium-sized arteries such as the celiac, mesenteric, and renal arteries (Correct answer)
Superficial femoral artery
Abdominal aorta

Correct answer: Medium-sized arteries such as the celiac, mesenteric, and renal arteries

EDS type IV causes deficient type III collagen, predisposing medium-caliber visceral and renal arteries (and gut) to spontaneous rupture.

Question 44: A 55-year-old male runner presents with exertional leg pain. Resting ABI is 1.0 bilaterally. Post-exercise ABI drops to 0.6 bilaterally and recovers in 3 minutes. He has no risk factors for PAD. Which diagnosis should be considered FIRST?

Bilateral superficial femoral artery disease
Popliteal artery entrapment syndrome (Correct answer)
Medial tibial stress syndrome
Exertional compartment syndrome

Correct answer: Popliteal artery entrapment syndrome

Popliteal artery entrapment syndrome classically presents in young, athletic males with normal resting ABIs and significant post-exercise ABI drops due to muscular compression of the popliteal artery.

Question 45: According to KDOQI clinical guidelines, what minimum access flow volume (Qa) is generally considered adequate for a functioning AV fistula to support hemodialysis?

100–200 mL/min
200–300 mL/min
400–500 mL/min (Correct answer)
800–1000 mL/min

Correct answer: 400–500 mL/min

KDOQI guidelines recommend a minimum Qa of approximately 400–500 mL/min for AV fistulas to sustain adequate dialysis clearance. Values below this threshold, particularly when declining on serial measurements, indicate a hemodynamically significant stenosis and trigger further evaluation or intervention.

Question 46: Which educational credential type is accepted as an alternative prerequisite pathway for the ARDMS RVT exam?

Associate degree in business administration
Certificate from any online health course
Bachelor's degree in kinesiology
Graduate degree from an CAAHEP-accredited vascular technology program (Correct answer)

Correct answer: Graduate degree from an CAAHEP-accredited vascular technology program

Completion of a CAAHEP-accredited vascular technology program is one accepted educational prerequisite pathway for the ARDMS RVT examination.

Question 47: The posterior inferior cerebellar artery (PICA) most commonly originates from the:

Basilar artery
Vertebral artery (Correct answer)
Posterior cerebral artery
Superior cerebellar artery

Correct answer: Vertebral artery

PICA typically arises from the distal intracranial vertebral artery, and its occlusion causes the lateral medullary (Wallenberg) syndrome.

Question 48: On duplex ultrasound, a post-stenotic flow pattern distal to a high-grade ICA stenosis is characterized by:

Normal triphasic waveform
Reversed diastolic flow
High-resistance monophasic waveform
Tardus-parvus waveform with delayed systolic upstroke (Correct answer)

Correct answer: Tardus-parvus waveform with delayed systolic upstroke

Tardus-parvus (slow-rising, rounded systolic peak with reduced amplitude) waveform is the classic post-stenotic pattern seen distal to significant stenosis.

Question 49: Which pathological process is the primary cause of most infrarenal abdominal aortic aneurysms?

Fibromuscular dysplasia
Infectious (mycotic) destruction of the wall
Cystic medial degeneration
Atherosclerosis with inflammatory degradation of the media and adventitia (Correct answer)

Correct answer: Atherosclerosis with inflammatory degradation of the media and adventitia

Atherosclerosis combined with inflammatory mediators (MMPs, T-cells) causes degradation of medial elastin and collagen, leading to infrarenal AAA.

Question 50: A synthetic aortobifemoral bypass graft is being evaluated. Flow in the right limb is triphasic and normal. The left limb shows monophasic, low-velocity waveforms. The most likely cause is:

Bilateral iliac disease
Contralateral steal from the right limb
Aortic anastomotic pseudoaneurysm
Stenosis or occlusion of the left graft limb or its outflow (Correct answer)

Correct answer: Stenosis or occlusion of the left graft limb or its outflow

Asymmetric waveforms between graft limbs indicate a unilateral problem; monophasic low-velocity waveforms in the left limb suggest stenosis or occlusion within that limb or distal to it.

Question 51: Which AIUM/NEMA safety index estimates the likelihood of cavitation in tissue?

Spatial peak pulse average intensity (ISPPA)
Mechanical index (MI) (Correct answer)
Thermal index (TI)
Spatial average temporal average intensity (ISATA)

Correct answer: Mechanical index (MI)

The Mechanical Index (MI = peak negative pressure / √frequency) estimates the potential for cavitation, with values above 0.3 suggesting increased risk.

Question 52: When documenting a carotid duplex examination, which finding most accurately represents a 70–99% internal carotid artery stenosis by the Society of Radiologists in Ultrasound (SRU) criteria?

ICA end-diastolic velocity < 40 cm/s with visible plaque
ICA PSV ≥ 230 cm/s with ICA/CCA PSV ratio ≥ 4.0 (Correct answer)
ICA PSV 125–229 cm/s with ICA/CCA ratio < 2.0
ICA PSV 100–124 cm/s with no plaque

Correct answer: ICA PSV ≥ 230 cm/s with ICA/CCA PSV ratio ≥ 4.0

The SRU consensus criteria define ≥70% ICA stenosis as ICA PSV ≥230 cm/s AND an ICA/CCA PSV ratio ≥4.0, often accompanied by ICA EDV ≥100 cm/s. Using both absolute velocity and the ratio improves accuracy and accounts for hemodynamic variability between patients.

Question 53: How is the RVT examination administered according to ARDMS guidelines?

Oral examination before a review panel
Portfolio-based assessment submitted online
Paper-based at testing centers twice yearly
Computer-based adaptive testing at Prometric centers (Correct answer)

Correct answer: Computer-based adaptive testing at Prometric centers

The RVT exam is administered via computer-based testing at Prometric centers, allowing candidates to test year-round.

Question 54: For the experience-based RVT pathway, in which imaging modality must the documented clinical studies primarily be performed?

CT angiography
Diagnostic vascular ultrasound (Correct answer)
Nuclear medicine perfusion imaging
Magnetic resonance angiography (MRA)

Correct answer: Diagnostic vascular ultrasound

The clinical experience must consist of diagnostic vascular ultrasound examinations, reflecting the core competency tested by the RVT credential.

Question 55: What is the expected spectral Doppler waveform morphology in a normally functioning, mature lower extremity reversed saphenous vein bypass graft that is supplying the ankle and foot?

A 'tardus parvus' waveform
A continuous, non-pulsatile venous-like signal
Low-resistance, monophasic with high diastolic flow
High-resistance, multiphasic (triphasic or biphasic) (Correct answer)

Correct answer: High-resistance, multiphasic (triphasic or biphasic)

A bypass graft assumes the hemodynamic characteristics of the vascular bed it supplies. Since the arteries of a resting lower extremity are a high-resistance bed, a normal graft waveform should be high-resistance, meaning it will be multiphasic (triphasic or strongly biphasic) with sharp systolic upstroke and minimal diastolic flow. [23]

Question 56: Which segment of the vertebral artery (V1-V4) is most accessible to duplex ultrasound and is the most common site for atherosclerosis?

V4 - intradural segment to basilar junction
V3 - from C2 to dura (atlantoaxial loop)
V1 - origin from subclavian to C6 transverse foramen (Correct answer)
V2 - within the transverse foramina C6 to C2

Correct answer: V1 - origin from subclavian to C6 transverse foramen

The V1 segment at the vertebral artery origin from the subclavian is the most common site of atherosclerosis and is accessible to duplex imaging.

Question 57: During transcranial Doppler (TCD) monitoring, a high-intensity transient signal (HITS) most likely represents:

Artifact from patient movement
Normal turbulent flow at the MCA bifurcation
Venous air embolism from deep breathing
Circulating microemboli (gaseous or particulate) (Correct answer)

Correct answer: Circulating microemboli (gaseous or particulate)

HITS detected during TCD monitoring represent microemboli (air or solid particles) passing through the insonated vessel and are a marker of embolic risk.

Question 58: A patient with subclavian steal syndrome will demonstrate which finding on vertebral artery duplex?

Absence of Doppler signal bilaterally
Monophasic low-resistance antegrade flow
Complete reversal of flow direction throughout the cardiac cycle (Correct answer)
Antegrade high-velocity flow throughout systole and diastole

Correct answer: Complete reversal of flow direction throughout the cardiac cycle

Complete subclavian steal causes full reversal of vertebral artery flow as blood is 'stolen' retrograde to supply the ischemic subclavian artery territory.

Question 59: Which finding on abdominal aortic duplex indicates a hemodynamically significant aortic aneurysm requiring surgical consultation?

Aortic diameter of 3.0 cm with smooth walls
Aortic diameter ≥ 5.5 cm or rapid growth > 0.5 cm in 6 months (Correct answer)
Infrarenal calcification without measurable dilation
Aortic PSV > 150 cm/s without dilation

Correct answer: Aortic diameter ≥ 5.5 cm or rapid growth > 0.5 cm in 6 months

An abdominal aortic aneurysm ≥ 5.5 cm diameter or growing > 0.5 cm in 6 months meets the threshold for surgical or endovascular repair consultation.

Question 60: What career path does the RDCS (Registered Diagnostic Cardiac Sonographer) credential open for an existing RVT?

Surgical scrub technologist positions
Transition into nuclear medicine technology
Dual-credentialed roles in combined vascular/echocardiography laboratories (Correct answer)
Radiation therapy planning

Correct answer: Dual-credentialed roles in combined vascular/echocardiography laboratories

Holding both RVT and RDCS credentials qualifies technologists for combined vascular/echo labs, which are increasingly common in cardiovascular centers of excellence.

Question 61: Which anatomical variant describes the absence of one segment of the Circle of Willis, making a patient more vulnerable to stroke if a feeding vessel is occluded?

Duplicated MCA
Persistent trigeminal artery
Aplastic or hypoplastic communicating artery (Correct answer)
Fenestrated basilar artery

Correct answer: Aplastic or hypoplastic communicating artery

Aplasia or hypoplasia of communicating arteries (ACoA or PCoA) limits collateral flow reserve, increasing stroke risk when a major feeding vessel is compromised.

Question 62: During upper extremity venous duplex imaging, which vein is most commonly involved in effort-related (Paget-Schroetter) thrombosis?

Basilic vein
Cephalic vein
Internal jugular vein
Subclavian vein (Correct answer)

Correct answer: Subclavian vein

Paget-Schroetter syndrome involves thrombosis of the axillo-subclavian vein, typically related to repetitive arm activity.

Question 63: When measuring the maximum diameter of an abdominal aortic aneurysm (AAA) via duplex ultrasound for surveillance, which of the following is the standard, most reproducible technique?

Anterior-posterior diameter measured from outer wall to outer wall in a transverse plane. (Correct answer)
Anterior-posterior diameter measured from inner wall to inner wall in a sagittal plane.
Lumen diameter only, excluding any mural thrombus, in a transverse plane.
Transverse diameter measured from outer wall to outer wall in a sagittal plane.

Correct answer: Anterior-posterior diameter measured from outer wall to outer wall in a transverse plane.

The standard protocol for measuring an abdominal aortic aneurysm is to obtain the maximum anterior-posterior (AP) diameter from the outer wall to the outer wall. This measurement should be taken in a transverse plane, ensuring the calipers are perpendicular to the long axis of the aorta. This technique is the most accurate and reproducible for serial surveillance and clinical decision-making.

Question 64: When evaluating a patient for upper extremity arterial disease, a blood pressure difference greater than how many mmHg between arms is clinically significant?

30 mmHg
10 mmHg (Correct answer)
20 mmHg
5 mmHg

Correct answer: 10 mmHg

An inter-arm pressure difference >10 mmHg suggests subclavian or axillary artery stenosis and warrants further evaluation; >15-20 mmHg is considered diagnostic of subclavian steal syndrome.

Question 65: Which finding on renal duplex ultrasound is most indicative of renal artery occlusion rather than severe stenosis?

RAR greater than 3.5 with aliasing artifact
Reversed diastolic flow in the interlobar arteries
Absence of Doppler signal in the main renal artery with a tardus-parvus waveform in the parenchyma (Correct answer)
Elevated PSV greater than 400 cm/s in the main renal artery

Correct answer: Absence of Doppler signal in the main renal artery with a tardus-parvus waveform in the parenchyma

Occlusion produces no detectable Doppler signal in the main renal artery, while residual parenchymal flow shows a tardus-parvus pattern from collateral supply.

Question 66: A technologist notices the real-time B-mode image has a 'dropout' artifact in the far field during routine phantom testing. The MOST likely cause is:

Incorrect Doppler angle selected
Time-gain compensation (TGC) set too low in the far field
Air bubble trapped between the transducer and the phantom surface (Correct answer)
Excessive gain setting

Correct answer: Air bubble trapped between the transducer and the phantom surface

Air has very high acoustic impedance mismatch with tissue/gel, causing near-total reflection and creating acoustic shadowing that eliminates signal in deeper structures.

Question 67: A 65-year-old man has a popliteal aneurysm repaired with an interposition vein graft. Duplex at 6 months shows the vein graft is patent with a mid-graft PSV of 45 cm/s and triphasic waveforms. This finding suggests:

Anastomotic pseudoaneurysm
A low-risk, well-functioning graft that should continue surveillance (Correct answer)
Graft arteriovenous fistula requiring repair
Impending thrombosis requiring urgent intervention

Correct answer: A low-risk, well-functioning graft that should continue surveillance

A mid-graft PSV of 45 cm/s with triphasic waveforms indicates adequate graft flow without focal stenosis; surveillance should continue per protocol.

Question 68: Which clinical scenario would most likely require an RVT to perform a bedside or portable vascular study?

ICU patient on mechanical ventilation with suspected DVT (Correct answer)
Pre-employment physical examination
Elective renal artery duplex in stable outpatient
Routine annual ABI screening in outpatient clinic

Correct answer: ICU patient on mechanical ventilation with suspected DVT

ICU patients on mechanical ventilation cannot safely be transported to the vascular lab, requiring the RVT to perform bedside portable duplex studies.

Question 69: What is the normal toe-brachial index (TBI) value in a healthy adult?

>0.80
>1.00
>0.40
>0.60 (Correct answer)

Correct answer: >0.60

A normal TBI is ≥0.70 in most references, with values below 0.60 generally considered abnormal and indicating significant digital arterial disease.

Question 70: The Mechanical Index (MI) displayed on an ultrasound machine is used to estimate the risk of:

Color Doppler aliasing artifacts
Thermal tissue heating from prolonged scanning
Cavitation and non-thermal mechanical bioeffects (Correct answer)
Electromagnetic interference with implanted devices

Correct answer: Cavitation and non-thermal mechanical bioeffects

The MI is the primary indicator of non-thermal mechanical bioeffects, particularly inertial cavitation, which is most relevant when scanning gas-filled structures or using contrast agents.

Question 71: In the context of RVT exam content, what does the term 'physiologic testing' refer to?

Histological analysis of vessel walls
Pharmacological stress testing
Laboratory blood flow simulations
Non-imaging tests such as ABI and segmental pressures (Correct answer)

Correct answer: Non-imaging tests such as ABI and segmental pressures

Physiologic testing refers to non-imaging vascular tests such as ankle-brachial index (ABI) and segmental limb pressures that assess hemodynamic status.

Question 72: What is the primary purpose of the Circle of Willis in the cerebrovascular system?

To provide a collateral pathway for cerebral perfusion (Correct answer)
To act as the main venous drainage system
To regulate intracranial pressure
To supply blood to the cerebellum

Correct answer: To provide a collateral pathway for cerebral perfusion

The Circle of Willis is an arterial anastomosis at the base of the brain that connects the anterior (internal carotid arteries) and posterior (vertebrobasilar system) circulations. Its primary function is to provide redundancy and collateral blood flow, which can help maintain cerebral perfusion if a major contributing artery becomes stenosed or occluded.

Question 73: On duplex surveillance of a PTFE above-knee femoropopliteal bypass graft, a focal PSV of 380 cm/s with a PSV ratio of 3.8 is found. What is the most appropriate next step?

Start anticoagulation and recheck in 1 month
Document as normal variant for PTFE grafts
Refer for angiography or intervention (Correct answer)
Repeat surveillance in 3 months

Correct answer: Refer for angiography or intervention

A PSV >300 cm/s with a ratio >3.5 indicates a severe stenosis (>70%), warranting urgent referral for angiographic evaluation and possible intervention.

Question 74: What is the primary duplex role during endovenous thermal ablation (EVTA) of the great saphenous vein?

Measuring total venous reflux time along the thigh
Guiding catheter tip placement and detecting endothermal heat-induced thrombosis (EHIT) post-procedure (Correct answer)
Confirming deep venous valve competence before ablation
Assessing arterial inflow to the limb

Correct answer: Guiding catheter tip placement and detecting endothermal heat-induced thrombosis (EHIT) post-procedure

Ultrasound guides correct catheter positioning (typically 2 cm distal to the saphenofemoral junction) and monitors tumescent anesthesia placement. Post-ablation, the technologist scans for EHIT — thrombus propagation into the deep system — which can occur in the first few days and requires classification and follow-up.

Question 75: During TCD microemboli monitoring, which characteristic helps differentiate a gaseous embolus from a particulate embolus?

Particulate emboli generate a chirping audible tone; gaseous emboli are silent on audio
Gaseous emboli cause unidirectional signals; particulate emboli cause bidirectional signals
Gaseous and particulate emboli cannot be reliably differentiated with standard TCD
Gaseous emboli produce high-intensity (typically >25 dB above background), bidirectional signals; particulate emboli are lower intensity and typically unidirectional (Correct answer)

Correct answer: Gaseous emboli produce high-intensity (typically >25 dB above background), bidirectional signals; particulate emboli are lower intensity and typically unidirectional

High-intensity transient signals (HITS) on TCD mark embolic events. Gaseous emboli (e.g., from cardiac bypass) reflect ultrasound very strongly (>25 dB), are bidirectional, and produce a distinctive 'chirp.' Particulate emboli (e.g., cholesterol, platelet aggregates) are typically lower intensity and unidirectional. This distinction has clinical implications for identifying cardiac vs. atherosclerotic embolic sources.

Question 76: An RVT completes an online module on duplex scanning of the renal arteries offered by an ARDMS-approved provider. This activity earns CME credit because:

The provider is ARDMS-approved and the module has a post-test (Correct answer)
The RVT personally requests credit from ARDMS
The topic is listed in the RVT exam blueprint
All online vascular content automatically qualifies

Correct answer: The provider is ARDMS-approved and the module has a post-test

CME credit requires an approved provider with structured learning objectives, often verified by a post-assessment.

Question 77: Which Doppler parameter is most sensitive for detecting a hemodynamically significant stenosis when peak systolic velocity is limited by low cardiac output?

Peak systolic velocity alone
Resistive index of the CCA
End-diastolic velocity alone
ICA-to-CCA peak systolic velocity ratio (Correct answer)

Correct answer: ICA-to-CCA peak systolic velocity ratio

The ICA/CCA PSV ratio normalizes for cardiac output, making it more reliable than absolute velocity in low-flow states; a ratio >4.0 indicates ≥70% stenosis.

Question 78: After endovascular aortic aneurysm repair (EVAR), which duplex finding indicates a Type II endoleak?

Flow between the graft fabric and the aortic wall at the proximal attachment site
Turbulent high-velocity flow within the graft lumen
Absence of any Doppler signal in the aneurysm sac
Flow within the aneurysm sac originating from a patent lumbar or inferior mesenteric artery (Correct answer)

Correct answer: Flow within the aneurysm sac originating from a patent lumbar or inferior mesenteric artery

A Type II endoleak is characterized by retrograde flow into the aneurysm sac from branch vessels such as lumbar arteries or the IMA.

Question 79: What is the primary purpose of ARDMS's Code of Ethics for RVT credential holders?

To establish professional and ethical standards guiding conduct in the credentialed specialty (Correct answer)
To set minimum salary standards for vascular technologists
To define equipment purchasing requirements for vascular labs
To regulate hospital billing practices for vascular studies

Correct answer: To establish professional and ethical standards guiding conduct in the credentialed specialty

The ARDMS Code of Ethics provides professional and ethical guidelines that RVT credential holders must uphold in their practice.

Question 80: An RVT with expertise in quality assurance and lab accreditation would be best suited for which administrative role?

Hospital billing specialist
Patient scheduling coordinator
Radiology information system (RIS) administrator
Vascular laboratory director or quality manager (Correct answer)

Correct answer: Vascular laboratory director or quality manager

Knowledge of quality assurance and accreditation standards directly qualifies an RVT to serve as a vascular laboratory director or quality manager overseeing IAC compliance.

Question 81: Which statement correctly describes the relationship between vessel radius and flow resistance according to Poiseuille's law?

Resistance is inversely proportional to the fourth power of radius (Correct answer)
Resistance is directly proportional to radius
Resistance is inversely proportional to the square of radius
Resistance is proportional to the cube of radius

Correct answer: Resistance is inversely proportional to the fourth power of radius

Poiseuille's law states R = 8ηL / πr⁴, meaning a 50% reduction in radius increases resistance 16-fold.

Question 82: A patient presents with left lower extremity swelling and pain. Duplex ultrasound reveals compression of the left common iliac vein by the overlying right common iliac artery. This finding is most consistent with:

Phlegmasia Cerulea Dolens
Klippel-Trenaunay Syndrome
May-Thurner Syndrome (Correct answer)
Paget-Schroetter Syndrome

Correct answer: May-Thurner Syndrome

May-Thurner Syndrome (MTS), also known as iliac vein compression syndrome, is a condition where the left common iliac vein is compressed by the right common iliac artery against the lumbar spine. This compression can impede venous outflow from the left leg, leading to swelling, pain, and an increased risk of DVT.

Question 83: Which electrical safety precaution is MOST important when operating ultrasound equipment near a patient with a temporary transvenous pacemaker?

Ensure the equipment is properly grounded and inspect for current leakage (Correct answer)
Use only battery-powered ultrasound units
Increase scan frequency to reduce electrical interference
Avoid scanning the chest entirely

Correct answer: Ensure the equipment is properly grounded and inspect for current leakage

Patients with temporary pacing leads have a direct electrical path to the myocardium; even small leakage currents from improperly grounded equipment can induce ventricular fibrillation.

Question 84: The carotid siphon refers to the S-shaped segment of the internal carotid artery located in the:

Neck at the carotid bifurcation
Cavernous sinus within the skull base (Correct answer)
Petrous temporal bone
Parapharyngeal space

Correct answer: Cavernous sinus within the skull base

The carotid siphon is the S-shaped intracranial portion of the ICA that courses through the cavernous sinus.

Question 85: How many Continuing Medical Education (CME) credits must an RVT earn during each 3-year renewal cycle to maintain ARDMS certification?

45 CME credits
60 CME credits
30 CME credits (Correct answer)
15 CME credits

Correct answer: 30 CME credits

ARDMS requires 30 CME credits per 3-year renewal cycle to maintain RVT certification.

Question 86: An RVT interested in advancing to a supervisory role should prioritize which additional credential?

American Registry for Diagnostic Medical Sonography (ARDMS) certificate in management (Correct answer)
Basic Life Support (BLS) recertification
Registered Diagnostic Medical Sonographer (RDMS)
Certified Phlebotomy Technician (CPT)

Correct answer: American Registry for Diagnostic Medical Sonography (ARDMS) certificate in management

Earning an ARDMS management certificate or similar leadership credential demonstrates readiness for supervisory responsibilities in a vascular lab setting.

Question 87: When performing pulse volume recordings (PVRs), what is the standard cuff inflation pressure used to sense volume changes in the limb segment without occluding arterial inflow?

Slightly above systolic pressure
65 mmHg (Correct answer)
20 mmHg
100 mmHg

Correct answer: 65 mmHg

For pulse volume recordings (PVRs), also known as air plethysmography, the cuffs are inflated to a pressure high enough to conform to the limb and detect volume changes, but low enough not to compress the arteries. A standard pressure of 60-65 mmHg is typically used for this purpose.

Question 88: Which patient preparation instruction is MOST important before performing a mesenteric arterial duplex examination?

Drink 32 oz of water to achieve a full bladder
NPO (nothing by mouth) for at least 6–8 hours prior to the exam (Correct answer)
No special preparation is required
Consume a high-fat meal 30 minutes before the scan

Correct answer: NPO (nothing by mouth) for at least 6–8 hours prior to the exam

Bowel gas from food or liquid intake significantly degrades visualization of the celiac axis and superior mesenteric artery. Fasting for 6–8 hours minimizes intraluminal gas and promotes mesenteric vasodilation, improving both image quality and the physiologic significance of post-prandial velocity changes.

Question 89: A vascular technologist is performing a Transcranial Doppler (TCD) examination through the transtemporal window. To identify the middle cerebral artery (MCA), what is the expected direction of blood flow relative to the transducer?

Away from the transducer
Antegrade (towards the transducer) (Correct answer)
Variable depending on patient position
Bidirectional

Correct answer: Antegrade (towards the transducer)

When insonating through the transtemporal window for a TCD exam, the ultrasound beam is typically aimed superiorly and slightly anteriorly. The middle cerebral artery (MCA) courses laterally from the circle of Willis, so its blood flow is directed towards the transducer, resulting in an antegrade or positive Doppler shift.

Question 90: A patient presents with transient monocular blindness (amaurosis fugax). Which artery is the most likely source of the embolic event?

Internal carotid artery ipsilateral to the affected eye (Correct answer)
Basilar artery
Vertebral artery
Posterior cerebral artery

Correct answer: Internal carotid artery ipsilateral to the affected eye

Amaurosis fugax is caused by emboli from the ipsilateral ICA traveling into the ophthalmic artery and its branch, the central retinal artery.

Question 91: During hepatic duplex evaluation after liver transplantation, which finding most urgently suggests hepatic artery thrombosis?

Mildly elevated hepatic artery PSV above 150 cm/s
Triphasic waveform in the hepatic artery
Mildly reduced portal vein velocity of 14 cm/s
Absent hepatic artery Doppler signal with no intrahepatic arterial flow (Correct answer)

Correct answer: Absent hepatic artery Doppler signal with no intrahepatic arterial flow

Complete absence of hepatic artery signal is the most critical finding, as hepatic artery thrombosis is a surgical emergency threatening graft survival.

Question 92: A sonographer measures a peak systolic velocity in the common carotid artery and notes that the Doppler angle of insonation is 75 degrees. What is the most likely consequence of using this angle for the velocity measurement?

The measurement will be accurate as long as the sample volume is small.
The velocity will be significantly overestimated.
Aliasing artifact will be minimized.
The velocity will be significantly underestimated. (Correct answer)

Correct answer: The velocity will be significantly underestimated.

The Doppler equation uses the cosine of the angle between the ultrasound beam and the direction of blood flow to calculate velocity. As this angle increases towards 90 degrees, its cosine value decreases sharply. Angles above 60 degrees introduce a large potential for error, leading to a significant underestimation of the true velocity.

Question 93: When mapping veins pre-operatively for EVLT (endovenous laser therapy), the minimum acceptable vein diameter at the saphenofemoral junction is typically:

8 mm
2 mm
5 mm (Correct answer)
3 mm

Correct answer: 5 mm

A minimum great saphenous vein diameter of approximately 5 mm at the junction is generally required for successful EVLT catheter placement.

Question 94: A patient presents with claudication. The right brachial pressure is 140 mmHg and the left brachial pressure is 130 mmHg. The right posterior tibial artery pressure is 70 mmHg and the right dorsalis pedis artery pressure is 65 mmHg. What is the correct Ankle-Brachial Index (ABI) for the right leg?

0.46
1.07
0.50 (Correct answer)
0.96

Correct answer: 0.50

To calculate the ABI, the highest ankle pressure on one side is divided by the highest of the two brachial pressures. In this case, the highest right ankle pressure is 70 mmHg (from the posterior tibial artery) and the highest brachial pressure is 140 mmHg. Therefore, 70 / 140 = 0.50. This value indicates moderate to severe peripheral arterial disease.

Question 95: A patient with subarachnoid hemorrhage has TCD MCA mean flow velocities of 190 cm/s bilaterally on day 7 post-bleed. What does this MOST likely indicate?

A normal post-hemorrhage hyperemic response
Bilateral MCA occlusion
Elevated intracranial pressure with preserved autoregulation
Cerebral vasospasm requiring clinical attention (Correct answer)

Correct answer: Cerebral vasospasm requiring clinical attention

TCD mean velocities >120 cm/s in the MCA after SAH are consistent with vasospasm, and velocities >200 cm/s indicate severe spasm. Peak vasospasm typically occurs days 5–14 post-SAH. Early TCD detection allows intervention (hemodynamic augmentation, nimodipine, angioplasty) before clinical deficits appear.

Question 96: What does the term 'duplex' refer to in vascular ultrasound examination content?

Two-dimensional grayscale imaging only
Color Doppler and power Doppler combined
Bilateral simultaneous limb assessment
Combination of B-mode imaging and pulsed-wave Doppler (Correct answer)

Correct answer: Combination of B-mode imaging and pulsed-wave Doppler

Duplex ultrasound combines real-time B-mode (grayscale) imaging with pulsed-wave Doppler to simultaneously visualize anatomy and assess blood flow.

Question 97: An RVT interested in entrepreneurship could most realistically pursue which independent business model?

Opening an independent surgical suite
Providing mobile vascular testing services under physician supervision contracts (Correct answer)
Running an independent MRI scanning center without physician oversight
Operating a stand-alone pharmacy

Correct answer: Providing mobile vascular testing services under physician supervision contracts

Mobile vascular testing services contracted to physician offices or rural clinics represent a viable entrepreneurial path for credentialed RVTs operating under required physician supervision agreements.

Question 98: Which organization specifically accredits vascular ultrasound testing laboratories in the United States for quality standards compliance?

The American College of Radiology (ACR) exclusively
The Intersocietal Accreditation Commission (IAC) (Correct answer)
ARDMS (the RVT credentialing body)
The Joint Commission (TJC)

Correct answer: The Intersocietal Accreditation Commission (IAC)

The IAC (Intersocietal Accreditation Commission) operates an accreditation program specifically for vascular testing laboratories, evaluating protocols, equipment, personnel credentials, report quality, and QA processes. Many payers and hospitals require IAC accreditation as a condition of reimbursement. ARDMS credentials individuals, not laboratories.

Question 99: Which examination must be passed in addition to a specialty examination to obtain the RVT credential through ARDMS?

Fetal Echocardiography (FE) exam
Abdominal Sonography (AB) exam
Neurosonology (NE) exam
Vascular Physics and Instrumentation (VPI) exam (Correct answer)

Correct answer: Vascular Physics and Instrumentation (VPI) exam

Candidates must pass the Vascular Physics and Instrumentation (VPI) examination along with the Vascular Technology (VT) specialty exam to earn the RVT credential.

Question 100: During peripheral arterial physiologic testing, what is the significance of a 'pole test' (elevation test)?

It determines the critical closing pressure of limb arteries by elevating the limb until Doppler signal disappears (Correct answer)
It identifies deep vein thrombosis by elevation-induced pain
It measures the increase in cardiac output with limb elevation
It assesses venous valve competence in the lower extremity

Correct answer: It determines the critical closing pressure of limb arteries by elevating the limb until Doppler signal disappears

The pole test elevates the limb to determine the height at which Doppler signal disappears, estimating the effective perfusion pressure in critically ischemic limbs when cuff pressures are unreliable.

Question 101: A 68-year-old male presents with episodes of dizziness, vertigo, and bilateral visual disturbances. A carotid duplex ultrasound reveals antegrade flow in both internal carotid arteries and the right vertebral artery. However, the left vertebral artery demonstrates sustained retrograde flow. What is the most likely diagnosis?

Bilateral carotid artery stenosis
Left subclavian steal syndrome (Correct answer)
Right subclavian steal syndrome
Vertebrobasilar insufficiency

Correct answer: Left subclavian steal syndrome

Subclavian steal syndrome is characterized by the reversal of blood flow in the vertebral artery on the same side as a significant stenosis or occlusion of the proximal subclavian artery. The retrograde flow in the left vertebral artery indicates that blood is being 'stolen' from the posterior circulation to supply the left arm, which is diagnostic of left subclavian steal syndrome.

Question 102: The acoustic impedance of a medium is determined by:

Attenuation coefficient and depth
Density and propagation speed (Correct answer)
Pulse duration and duty factor
Frequency and wavelength

Correct answer: Density and propagation speed

Acoustic impedance (Z) equals the product of the medium's density (ρ) and the speed of sound (c) in that medium: Z = ρc.

Question 103: What is the most common anatomic location and cause of AV graft thrombosis?

Mid-graft kinking due to patient positioning
Infection-related thrombosis at needle puncture sites
Arterial inflow stenosis at the graft-artery anastomosis
Venous outflow stenosis, most often at the graft-vein anastomosis (Correct answer)

Correct answer: Venous outflow stenosis, most often at the graft-vein anastomosis

The venous outflow — particularly the graft-to-vein anastomosis — is the most common site of stenosis in AV grafts because neo-intimal hyperplasia preferentially develops at this venous anastomosis. The resulting outflow obstruction raises circuit pressure, reduces flow, and ultimately leads to thrombosis if untreated.

Question 104: Which of the following is the first major branch of the internal carotid artery (ICA) after it enters the cranial cavity?

Posterior communicating artery
Ophthalmic artery (Correct answer)
Middle cerebral artery
Anterior cerebral artery

Correct answer: Ophthalmic artery

The ophthalmic artery is typically the first major branch arising from the supraclinoid segment of the internal carotid artery after it passes through the cavernous sinus and enters the cranial cavity. It supplies blood to the structures of the orbit.

Question 105: Which parameter obtained during peripheral arterial physiologic testing BEST predicts primary amputation healing at the below-knee level?

Below-knee or ankle systolic pressure >70 mmHg or toe pressure >30 mmHg (Correct answer)
Popliteal artery duplex velocity
Resting ABI at the ankle
Presence of triphasic waveform at the popliteal level

Correct answer: Below-knee or ankle systolic pressure >70 mmHg or toe pressure >30 mmHg

Below-knee amputation healing is most reliably predicted by adequate perfusion pressure, with ankle or BK pressures >70 mmHg and toe pressures >30 mmHg associated with successful primary healing.

Question 106: What is the duration of the RVT certification exam?

4 hours
3 hours (Correct answer)
2 hours
5 hours

Correct answer: 3 hours

The RVT certification exam has a duration of 3 hours. This time frame allows candidates sufficient opportunity to carefully read and answer all 170 multiple-choice questions. It ensures a thorough assessment of their knowledge in both ultrasound physics and vascular technology without undue time pressure.

Question 107: A patient with Raynaud's phenomenon undergoes cold stimulation testing. Which finding would confirm vasospastic disease rather than fixed obstruction?

Persistent absence of digital Doppler signal after rewarming
No change in digital PPG waveform with cold exposure
Bilateral ABI reduction during cold exposure
Complete recovery of digital waveform amplitude after rewarming to 37°C (Correct answer)

Correct answer: Complete recovery of digital waveform amplitude after rewarming to 37°C

Vasospastic Raynaud's phenomenon is characterized by reversible digital vessel spasm that resolves completely with rewarming, distinguishing it from fixed structural obstruction.

Question 108: Which condition is most associated with spontaneous carotid artery dissection in young patients without atherosclerotic risk factors?

Hypertensive emergency
Hyperlipidemia
Fibromuscular dysplasia (Correct answer)
Diabetes mellitus type 2

Correct answer: Fibromuscular dysplasia

FMD weakens the arterial wall media, predisposing young patients to spontaneous dissection of the ICA or vertebral artery.

Question 109: Which statement about ethics violations and RVT credential status is accurate?

ARDMS may investigate and revoke credentials for documented ethical violations (Correct answer)
Only criminal convictions can affect ARDMS credential status
ARDMS has no jurisdiction over ethical conduct after certification
Ethics violations are handled solely by the employer, not ARDMS

Correct answer: ARDMS may investigate and revoke credentials for documented ethical violations

ARDMS has a Code of Ethics and can investigate complaints, and may suspend or revoke credentials for substantiated violations.

Question 110: What is the primary advantage of pulse volume recordings (PVR) over segmental limb pressures in patients with calcified vessels?

PVR is more sensitive for detecting mild disease
PVR can identify specific anatomic stenosis locations more accurately
PVR assesses volume changes rather than compressibility, making it reliable despite vessel calcification (Correct answer)
PVR provides direct measurement of arterial pressure

Correct answer: PVR assesses volume changes rather than compressibility, making it reliable despite vessel calcification

PVR measures limb volume changes with each cardiac cycle using air plethysmography, which is not affected by vessel wall stiffness or calcification, unlike pressure-based measurements.

Question 111: A diabetic patient has non-compressible tibial arteries with ABIs >1.3. Which alternative test is MOST reliable for assessing arterial perfusion in this patient?

Segmental limb pressures
Toe-brachial index (TBI) (Correct answer)
CT angiography without contrast
Venous duplex ultrasound

Correct answer: Toe-brachial index (TBI)

The toe arteries are typically spared from medial calcification in diabetics, making the TBI the preferred non-invasive pressure index when ABIs are non-compressible.

Question 112: Why is the RVT credential important in vascular technology?

It replaces the need for clinical experience.
It is required for all medical jobs.
It allows exemption from state licensure.
It demonstrates a commitment to professional excellence. (Correct answer)

Correct answer: It demonstrates a commitment to professional excellence.

The RVT credential is vital because it demonstrates a commitment to professional excellence in vascular technology. It signifies that an individual has met rigorous national standards of knowledge and skill, assuring employers and patients of their expertise. This certification enhances credibility and trust in the diagnostic services provided.

Question 113: In spectral Doppler, the filling-in of the clear space under the systolic peak is known as spectral broadening. This finding is most commonly associated with:

A Doppler gate placed in the center of the vessel.
Disturbed or turbulent blood flow. (Correct answer)
Laminar flow in a large, straight vessel.
A Doppler angle of exactly 90 degrees.

Correct answer: Disturbed or turbulent blood flow.

The clear area under the systolic peak, or 'spectral window,' represents the uniform velocity of red blood cells in laminar flow. Turbulent flow involves red blood cells moving at a wide variety of speeds and in multiple directions. This range of velocities fills in the spectral window, causing the appearance of spectral broadening.

Question 114: A 68-year-old woman has rest pain and an ABI of 0.38. Her toe pressure is 22 mmHg. According to TASC II criteria, this patient most likely has:

Claudication (Fontaine stage II)
Non-occlusive mesenteric ischemia
Mild peripheral arterial disease
Critical limb ischemia (Fontaine stage III-IV) (Correct answer)

Correct answer: Critical limb ischemia (Fontaine stage III-IV)

Critical limb ischemia is defined by rest pain or tissue loss with ankle pressure <50 mmHg or toe pressure <30 mmHg, consistent with this patient's findings.

Question 115: What is the primary cause of the 'to-and-fro' waveform pattern seen in a pseudoaneurysm neck on duplex ultrasound?

Reversed flow from proximal arterial occlusion
Arteriovenous shunting within the pseudoaneurysm
Bidirectional flow as blood enters during systole and exits during diastole (Correct answer)
Turbulent flow from thrombus within the sac

Correct answer: Bidirectional flow as blood enters during systole and exits during diastole

The neck of a pseudoaneurysm shows forward flow into the sac during systole and reverse flow back into the artery during diastole, creating the classic to-and-fro pattern.

Question 116: What is the primary advantage of working at an academic medical center for an RVT compared to a private practice?

No weekend or on-call requirements
Higher base salary in all geographic regions
Strictly limited patient volume
Access to cutting-edge research, complex cases, and teaching opportunities (Correct answer)

Correct answer: Access to cutting-edge research, complex cases, and teaching opportunities

Academic medical centers expose RVTs to complex, rare vascular pathology and offer involvement in research and student education not commonly found in private practice.

Question 117: Which RVT examination topic requires understanding of plaque morphology classification including echolucent vs. echogenic characteristics?

Venous reflux testing
Lower extremity venous mapping
Transcranial Doppler monitoring
Carotid artery duplex evaluation (Correct answer)

Correct answer: Carotid artery duplex evaluation

Carotid artery duplex evaluation includes plaque morphology assessment, where echolucent (soft) plaques carry higher embolic risk than echogenic (calcified) plaques.

Question 118: Which concept is critical to understanding Doppler angle correction in quantitative vascular examination?

The angle between the transducer and the skin surface
Angles above 80° improve sensitivity for low-flow states
The angle between the Doppler beam and the vessel axis should be ≤ 60° (Correct answer)
Doppler angle has no effect on velocity calculations

Correct answer: The angle between the Doppler beam and the vessel axis should be ≤ 60°

Doppler angle correction requires the angle between the ultrasound beam and blood flow direction to be ≤ 60° to minimize velocity calculation error from the cosine function.

Question 119: Which of the following best describes a 'primary-source verification' in the context of RVT credentialing?

A background check performed by a local police department
Confirmation of credential status directly from ARDMS, rather than from the credential holder (Correct answer)
A letter of recommendation from a supervisor
A copy of the candidate's academic transcript

Correct answer: Confirmation of credential status directly from ARDMS, rather than from the credential holder

Primary-source verification means an employer or institution confirms an RVT's credential status directly with ARDMS, the issuing body.

Question 120: After successfully renewing the RVT credential, the new expiration date is set to:

3 years from the original expiration date (Correct answer)
3 years from the date ARDMS processes the renewal
1 year from the original expiration date
5 years from the original issue date

Correct answer: 3 years from the original expiration date

ARDMS advances the expiration date by 3 years from the prior expiration, preserving the renewal cycle alignment.

Question 121: Which statement CORRECTLY describes the relationship between ankle-brachial index (ABI) values and cardiovascular risk?

Both low ABI (<0.9) and high ABI (>1.3) are independently associated with increased cardiovascular mortality (Correct answer)
ABI values are predictive of limb outcomes only, not cardiovascular events
Only low ABI values (<0.9) are associated with increased cardiovascular mortality
ABI >1.0 is always protective against cardiovascular events

Correct answer: Both low ABI (<0.9) and high ABI (>1.3) are independently associated with increased cardiovascular mortality

Both low ABI (reflecting atherosclerosis) and high ABI (reflecting arterial stiffness from calcification) are independently associated with increased cardiovascular morbidity and mortality.

Question 122: In portal vein duplex evaluation, normal portal vein flow is described as hepatopetal with a velocity of approximately:

16–40 cm/s with mild respiratory phasicity (Correct answer)
5–10 cm/s with marked phasicity
Greater than 100 cm/s with turbulent waveform
60–90 cm/s with continuous non-phasic flow

Correct answer: 16–40 cm/s with mild respiratory phasicity

Normal portal vein flow is directed toward the liver (hepatopetal) at 16–40 cm/s, with slight variation related to respiration and cardiac pulsatility.

Question 123: A surveillance duplex of an above-knee femoropopliteal PTFE graft shows a mid-graft PSV of 18 cm/s. What is the most appropriate action?

No action; low velocity is expected in PTFE grafts
Urgent clinical referral for angiography, as low graft velocity predicts impending thrombosis (Correct answer)
Repeat in 6 months as per standard protocol
Prescribe aspirin and recheck in 3 months

Correct answer: Urgent clinical referral for angiography, as low graft velocity predicts impending thrombosis

A mid-graft PSV <25 cm/s is a strong predictor of impending graft thrombosis and warrants urgent clinical evaluation and possible intervention.

Question 124: Which duplex protocol modification is most appropriate when attempting to image the renal arteries in an obese patient with a technically difficult examination?

Switch to a high-frequency linear transducer for improved resolution
Use a lower frequency curved transducer, optimize depth and focus, and try decubitus or posterior flank approaches (Correct answer)
Ask the patient to suspend breathing in expiration for the entire exam
Increase color Doppler velocity scale to eliminate aliasing

Correct answer: Use a lower frequency curved transducer, optimize depth and focus, and try decubitus or posterior flank approaches

Lower frequency transducers provide better penetration in obese patients, and alternative scan windows such as the flank approach can bypass bowel gas and adipose tissue.

Question 125: During segmental pressure testing, a 30 mmHg pressure gradient is found between the proximal thigh and above-knee segments. Where is the disease most likely located?

Tibial vessels
Popliteal artery
Superficial femoral artery (Correct answer)
Aortoiliac segment

Correct answer: Superficial femoral artery

A gradient >20 mmHg between proximal thigh and above-knee cuffs localizes disease to the superficial femoral artery in the mid-thigh region.

Question 126: A tardus-parvus waveform pattern distal to an arterial obstruction is characterized by:

Triphasic waveform with increased peak systolic velocity
Absent diastolic flow with normal systolic velocity
Delayed, rounded systolic peak with reduced amplitude and loss of diastolic reversal (Correct answer)
Rapid systolic upstroke and high peak velocity

Correct answer: Delayed, rounded systolic peak with reduced amplitude and loss of diastolic reversal

Tardus-parvus (slow-small) describes the damped, delayed waveform seen downstream from a hemodynamically significant stenosis or occlusion.

Question 127: During splenic artery duplex evaluation, the normal waveform pattern reflects which hemodynamic state?

Monophasic flat waveform with no diastolic component
Pulsatile bidirectional flow synchronous with respiration
Low-resistance flow with continuous forward diastolic flow (Correct answer)
High-resistance triphasic flow with brief flow reversal

Correct answer: Low-resistance flow with continuous forward diastolic flow

The splenic parenchyma is a low-resistance vascular bed, so the splenic artery normally displays continuous forward diastolic flow similar to other visceral vessels.

Question 128: A patient with diabetes and suspected digital ischemia undergoes photoplethysmography (PPG) of the great toe. The resulting waveform is severely dampened with a delayed upstroke and a rounded peak. What is the most likely interpretation of this finding?

Significant proximal arterial occlusive disease (Correct answer)
Vasospastic disorder
Normal arterial inflow
Venous insufficiency

Correct answer: Significant proximal arterial occlusive disease

Photoplethysmography (PPG) assesses changes in blood volume in the capillary beds. A normal PPG waveform has a sharp systolic upstroke and a dicrotic notch. A dampened, rounded waveform with a slow upstroke indicates poor arterial perfusion, which is characteristic of significant proximal (upstream) arterial stenosis or occlusion that reduces pulsatile flow to the digits.

Question 129: In renal artery duplex assessment, which indirect parameter best reflects significant proximal renal artery stenosis when direct visualization is limited?

Peak systolic velocity in the arcuate arteries
Renal volume index
Renal cortex thickness
Renal acceleration time and acceleration index (Correct answer)

Correct answer: Renal acceleration time and acceleration index

Acceleration time >70–100 ms and acceleration index <300 cm/s² in intrarenal segmental arteries are indirect indicators of significant proximal renal artery stenosis.

Question 130: Fibromuscular dysplasia (FMD) of the internal carotid artery most commonly affects which segment?

Cavernous ICA siphon
Mid-cervical ICA (C1-C2 level) (Correct answer)
Proximal ICA just above the bifurcation
Petrous ICA

Correct answer: Mid-cervical ICA (C1-C2 level)

FMD most commonly affects the mid-cervical segment of the ICA at the C1-C2 vertebral level, producing the classic 'string of beads' appearance.

Question 131: Which duplex finding best distinguishes carotid plaque hemorrhage from calcified plaque?

Calcified plaque appears isoechoic to surrounding tissue
Hemorrhagic plaque appears hypoechoic or heterogeneous without shadowing; calcified plaque shows dense shadowing (Correct answer)
Hemorrhagic plaque appears highly echogenic with acoustic shadowing
Hemorrhagic plaque always shows posterior enhancement

Correct answer: Hemorrhagic plaque appears hypoechoic or heterogeneous without shadowing; calcified plaque shows dense shadowing

Intraplaque hemorrhage appears hypoechoic or heterogeneous on ultrasound, while calcification produces bright echoes with posterior acoustic shadowing.

Question 132: Hollenhorst plaques seen on fundoscopic examination are cholesterol emboli originating most commonly from:

Atherosclerotic plaque in the ipsilateral carotid artery (Correct answer)
Cardiac valve vegetations
Vertebrobasilar system
Aortic arch thrombus only

Correct answer: Atherosclerotic plaque in the ipsilateral carotid artery

Hollenhorst plaques are refractile cholesterol crystals lodged in retinal arterioles, typically originating from ulcerated atherosclerotic plaque in the ipsilateral ICA.

Question 133: Which of the following best describes the concept of 'critical stenosis' in arterial hemodynamics?

Any stenosis detectable by duplex ultrasound
A 30% diameter reduction causing turbulence
The degree of stenosis that begins to reduce resting blood flow (Correct answer)
Total vessel occlusion with no collateral pathways

Correct answer: The degree of stenosis that begins to reduce resting blood flow

Critical stenosis is the threshold (typically ~50–75% diameter reduction) at which the pressure gradient across the lesion begins to reduce resting volumetric flow.

Question 134: Harmonic imaging in vascular ultrasound primarily reduces which artifact?

Near-field clutter and side-lobe artifacts (Correct answer)
Spectral broadening from angle errors
Color Doppler aliasing
Shadowing from calcified plaque

Correct answer: Near-field clutter and side-lobe artifacts

Tissue harmonic imaging uses second-harmonic frequencies that are generated within tissue, reducing near-field clutter and side-lobe artifacts for improved image quality.

Question 135: On a PVR tracing, which feature represents the dicrotic notch, and what does its absence indicate?

A small notch on the downstroke; absence indicates loss of arterial compliance or significant disease (Correct answer)
A secondary positive wave; absence indicates cardiac arrhythmia
The initial upstroke; absence indicates venous reflux
The peak of the waveform; absence indicates arterial calcification

Correct answer: A small notch on the downstroke; absence indicates loss of arterial compliance or significant disease

The dicrotic notch on the descending limb of the PVR waveform represents aortic valve closure; its absence distal to a stenosis reflects dampening of pulsatility.

Question 136: During surveillance of a prosthetic femoropopliteal bypass graft, a focal area of color aliasing is noted mid-graft. The peak systolic velocity (PSV) within this segment is 320 cm/s. The PSV in a normal-appearing graft segment just proximal to this area is 150 cm/s. What is the velocity ratio (Vr), and what is the most likely interpretation?

Vr = 0.47; Suggests proximal disease
Vr = 1.7; Mild (<50%) stenosis
Vr = 2.1; Significant (≥50%) stenosis (Correct answer)
Vr = 2.5; Suggests impending occlusion

Correct answer: Vr = 2.1; Significant (≥50%) stenosis

The velocity ratio (Vr) is calculated by dividing the highest PSV at the stenosis (320 cm/s) by the PSV in a normal proximal segment (150 cm/s), which equals 2.13. A Vr ≥ 2.0 is a widely accepted criterion indicating a hemodynamically significant stenosis of 50% or greater in a peripheral bypass graft. [14]

Question 137: The normal intima-media thickness (IMT) of the common carotid artery in adults under 50 years is generally accepted as less than:

0.9 mm (Correct answer)
1.2 mm
1.5 mm
0.5 mm

Correct answer: 0.9 mm

An IMT of less than 0.9 mm is generally considered normal in adults, while values ≥1.0 mm suggest subclinical atherosclerosis.

Question 138: A 'string sign' seen on duplex ultrasound of the ICA most likely represents:

Normal low-flow state in a fasting patient
Arteriovenous fistula
Carotid body tumor compressing the vessel
Near-total occlusion with a thin residual lumen (Correct answer)

Correct answer: Near-total occlusion with a thin residual lumen

The string sign describes a thin trickle of flow through a near-totally occluded ICA, distinguishing it from complete occlusion.

Question 139: When performing a duplex ultrasound to evaluate for venous insufficiency, which patient position is considered optimal for eliciting venous reflux?

Standing with weight on the contralateral leg. (Correct answer)
Left lateral decubitus.
Reverse Trendelenburg at a 15-degree angle.
Supine with the head of the bed flat.

Correct answer: Standing with weight on the contralateral leg.

To accurately assess for venous reflux, the patient should be positioned to maximize hydrostatic pressure in the lower extremities, which challenges the vein valves. The standing position is the gold standard as it allows gravity to have its full effect. If standing is not possible, a steep reverse Trendelenburg position is an alternative, but standing is preferred.

Question 140: The Nyquist limit in pulsed wave Doppler determines the maximum detectable Doppler shift without aliasing, which equals:

The transducer frequency
Half the pulse repetition frequency (PRF/2) (Correct answer)
The pulse repetition frequency (PRF)
Twice the pulse repetition frequency (2×PRF)

Correct answer: Half the pulse repetition frequency (PRF/2)

Aliasing occurs when the Doppler shift exceeds the Nyquist limit, which is one-half of the pulse repetition frequency.

Question 141: An RVT who moves to a different U.S. state — what must they do regarding their ARDMS credential?

Apply for a new RVT exam in the new state
Surrender the credential and obtain a state license instead
Retake the VPI exam only
Notify ARDMS of the address change; the credential remains valid nationally (Correct answer)

Correct answer: Notify ARDMS of the address change; the credential remains valid nationally

The RVT is a national credential, so moving states does not invalidate it; the credential holder should update their address with ARDMS.

Question 142: A peak systolic velocity of 220 cm/s with an end-diastolic velocity of 85 cm/s in the ICA corresponds to which NASCET stenosis category per the Society of Radiologists in Ultrasound (SRU) consensus criteria?

Near occlusion
Less than 50% stenosis
50-69% stenosis
70-99% stenosis (Correct answer)

Correct answer: 70-99% stenosis

Per SRU criteria, ICA PSV ≥125 cm/s with EDV ≥40 cm/s and ICA/CCA ratio >2.0 indicates 70-99% stenosis requiring closer evaluation.

Question 143: Which Doppler waveform characteristic differentiates the external carotid artery from the internal carotid artery?

ECA has low-resistance continuous diastolic flow; ICA has none
ECA has high-resistance pulsatile flow with little or no diastolic flow; ICA has continuous low-resistance flow (Correct answer)
ECA shows bidirectional flow; ICA shows monodirectional flow
ECA has higher peak systolic velocity than ICA in all individuals

Correct answer: ECA has high-resistance pulsatile flow with little or no diastolic flow; ICA has continuous low-resistance flow

The ECA supplies high-resistance muscle and skin beds, producing a pulsatile waveform with minimal diastole, while the ICA supplies the low-resistance brain with continuous diastolic flow.

Question 144: The vertebral arteries typically originate from which vessels?

Aortic arch directly
Common carotid arteries
Subclavian arteries (Correct answer)
Brachiocephalic trunk bilaterally

Correct answer: Subclavian arteries

The vertebral arteries arise from the subclavian arteries bilaterally and ascend through the transverse foramina of C6 to C1.

Question 145: When performing a lower extremity venous duplex exam, which vein is typically evaluated at the popliteal fossa?

Gastrocnemius vein only
Anterior tibial vein and peroneal vein
Small saphenous vein and popliteal vein (Correct answer)
Great saphenous vein and femoral vein

Correct answer: Small saphenous vein and popliteal vein

The popliteal fossa is the anatomical window where both the popliteal vein and the small saphenous vein are routinely evaluated.

Question 146: What is the average salary range for an RVT in the United States?

$80,000 - $100,000
$50,000 - $60,000
$60,000 - $80,000 (Correct answer)
$40,000 - $50,000

Correct answer: $60,000 - $80,000

The average salary range for an RVT in the United States typically falls between $60,000 and $80,000 annually. This range can fluctuate based on factors such as geographic location, years of experience, and the type of healthcare facility. RVTs are highly skilled professionals, and their specialized expertise is reflected in competitive compensation.

Question 147: An increased pulsatility index (PI) proximal to a segment of arterial occlusion suggests:

Hyperdynamic cardiac function
Increased downstream resistance due to the obstruction (Correct answer)
Arteriovenous fistula formation
Improved collateral circulation

Correct answer: Increased downstream resistance due to the obstruction

Proximal to an occlusion, high outflow resistance causes the waveform to become more pulsatile with reduced or absent diastolic flow.

Question 148: What is the primary eligibility requirement to sit for the RVT exam?

A bachelor's degree in any field
Membership in a professional sonography organization
At least five years of healthcare experience
Completion of an accredited sonography program (Correct answer)

Correct answer: Completion of an accredited sonography program

To ensure candidates possess the foundational knowledge and practical skills required for vascular sonography, the ARDMS mandates completion of an accredited diagnostic medical sonography program. This educational pathway provides the comprehensive training necessary to perform vascular ultrasound examinations safely and effectively, preparing individuals for the rigorous RVT exam.

Question 149: Which waveform characteristic on PVR (pulse volume recording) is MOST consistent with proximal aortoiliac occlusive disease?

Normal waveform at thigh with abnormal calf waveform
Biphasic waveform at the ankle with triphasic at the thigh
Peaked systolic upstroke with sharp dicrotic notch
Flat, broad waveform with absent dicrotic notch throughout the limb (Correct answer)

Correct answer: Flat, broad waveform with absent dicrotic notch throughout the limb

Aortoiliac disease produces diffusely flattened, broadened PVR waveforms throughout the entire lower extremity due to inflow obstruction affecting all segments.

Question 150: The peak systolic velocity ratio (PSVR) used to grade arterial stenosis severity is calculated as:

PSV at the stenosis divided by PSV measured distal to the stenosis
Mean velocity at the stenosis divided by resistive index
PSV at the stenosis divided by PSV in the adjacent proximal normal arterial segment (Correct answer)
End-diastolic velocity divided by peak systolic velocity at the stenosis

Correct answer: PSV at the stenosis divided by PSV in the adjacent proximal normal arterial segment

The PSVR compares the elevated velocity at the stenosis to the velocity in the proximal normal (pre-stenotic) segment. This ratio corrects for patient-to-patient variation in cardiac output and overall flow state, making it a more reliable indicator of stenosis severity than an absolute PSV value alone.

Question 151: During evaluation of a hemodialysis access graft, a PSV of 400 cm/s is found at the venous anastomosis with a PSV ratio of 3.2. What is the clinical implication?

Normal finding at the venous anastomosis
Arterial inflow stenosis
Significant venous anastomotic stenosis likely contributing to access dysfunction (Correct answer)
Graft thrombosis

Correct answer: Significant venous anastomotic stenosis likely contributing to access dysfunction

Elevated PSV (>400 cm/s) and PSV ratio >2.0 at the venous anastomosis of a dialysis graft indicate significant stenosis, the most common cause of access dysfunction.

Question 152: A vascular technologist performing a surveillance duplex identifies a new, complete thrombotic occlusion of a previously patent femoral-popliteal bypass graft. What is the MOST appropriate immediate action?

Communicate the finding urgently to the ordering physician or on-call clinical team before the patient leaves (Correct answer)
Schedule a 3-month follow-up duplex and note findings in the report
Repeat the exam in 24 hours to confirm the finding
Notify the patient's family and recommend emergency department evaluation

Correct answer: Communicate the finding urgently to the ordering physician or on-call clinical team before the patient leaves

Acute graft occlusion is a limb-threatening emergency requiring immediate clinical decision-making (thrombectomy, thrombolysis, or revision). The technologist must notify the responsible physician or clinical team while the patient is still present so that timely intervention can be arranged. Documenting without communication causes dangerous treatment delays.

Question 153: Which organization oversees RVT certification and renewal?

American Medical Association (AMA)
Society of Diagnostic Medical Sonography (SDMS)
American Registry for Diagnostic Medical Sonography (ARDMS) (Correct answer)
National Healthcareer Association (NHA)

Correct answer: American Registry for Diagnostic Medical Sonography (ARDMS)

The American Registry for Diagnostic Medical Sonography (ARDMS) is the authoritative organization that oversees RVT certification and renewal. ARDMS establishes the standards for competence in sonography, develops and administers certification exams, and manages the continuing education requirements for maintaining credentials. Their role ensures the integrity and quality of the RVT profession.

Question 154: Which hand hygiene product is considered MOST effective for reducing transmission of Clostridium difficile spores in a vascular laboratory setting?

Plain soap and water with thorough rinsing (Correct answer)
Chlorhexidine gluconate foam
Alcohol-based hand rub (ABHR)
Iodine-based antiseptic scrub

Correct answer: Plain soap and water with thorough rinsing

Alcohol-based hand rubs do not kill C. difficile spores; plain soap and water physically removes spores from the hands and is the recommended approach for C. diff prevention.

Question 155: In a stenotic vessel, where is the highest flow velocity observed according to the continuity equation?

At the site of maximum narrowing (Correct answer)
At the vessel wall
Proximal to the stenosis
Distal to the stenosis

Correct answer: At the site of maximum narrowing

The continuity equation (A1V1 = A2V2) requires velocity to increase at the point of greatest cross-sectional area reduction.

Question 156: Which clinical scenario would MOST warrant transcutaneous oxygen pressure (TcPO2) measurement as part of peripheral arterial physiologic testing?

Screening for PAD in an asymptomatic patient with diabetes
Differentiating claudication from spinal stenosis
Diagnosing proximal aortoiliac occlusion
Predicting wound healing potential in a patient with a non-healing foot ulcer (Correct answer)

Correct answer: Predicting wound healing potential in a patient with a non-healing foot ulcer

TcPO2 measures tissue oxygenation at the skin surface and is used to predict amputation wound healing potential; values <20-30 mmHg predict poor healing.

Question 157: In transcranial Doppler, the middle cerebral artery (MCA) is typically insonated through which window at a depth of 45-65 mm?

Submandibular window
Suboccipital (transforaminal) window
Transorbital window
Transtemporal window (Correct answer)

Correct answer: Transtemporal window

The transtemporal window, located above the zygomatic arch near the temporal bone, allows insonation of the MCA at depths of 45-65 mm.

Question 158: During ultrasound-guided central venous access, the primary advantage of real-time needle visualization over landmark technique is:

Confirmation of venous (vs. arterial) waveform before catheter insertion
Elimination of the need for post-procedure chest X-ray
Direct visualization of needle tip position within the target vessel lumen in real time (Correct answer)
Automatic calculation of catheter depth required

Correct answer: Direct visualization of needle tip position within the target vessel lumen in real time

Real-time ultrasound guidance allows the operator to see the needle tip entering the vessel lumen, confirming correct placement before guidewire advancement. This directly reduces complications such as inadvertent arterial puncture, pneumothorax, and posterior wall perforation compared to landmark-only technique.

Question 159: Which intraoperative duplex finding after infrainguinal bypass graft creation most likely warrants immediate surgical revision?

Focal peak systolic velocity ratio greater than 3:1 across an anastomotic segment (Correct answer)
Phasic (triphasic) flow pattern throughout the graft body
Mild color-flow turbulence immediately distal to the proximal anastomosis
Graft diameter slightly smaller than the native tibial artery

Correct answer: Focal peak systolic velocity ratio greater than 3:1 across an anastomotic segment

A PSV ratio >3:1 across a focal segment indicates a hemodynamically significant stenosis (≥75% diameter reduction). When found intraoperatively before the wound is closed, it signals a technical defect — suture narrowing, intimal flap, or kinking — that should be corrected immediately to prevent early graft failure.

Question 160: A patient with a history of 'food fear' and significant weight loss is evaluated for chronic mesenteric ischemia. In a fasting state, which of the following duplex findings would be most indicative of a hemodynamically significant (>70%) stenosis?

A low-resistance waveform in the superior mesenteric artery (SMA).
A peak systolic velocity (PSV) of 150 cm/s in the celiac artery.
Retrograde flow in the common hepatic artery.
A peak systolic velocity (PSV) greater than 280 cm/s in the superior mesenteric artery (SMA). (Correct answer)

Correct answer: A peak systolic velocity (PSV) greater than 280 cm/s in the superior mesenteric artery (SMA).

The most widely accepted duplex criterion for a hemodynamically significant stenosis (>70%) in the superior mesenteric artery (SMA) is a peak systolic velocity (PSV) of ≥275 cm/s in a fasting state. A low-resistance waveform in a fasting SMA is a normal post-prandial finding, not a sign of stenosis. A celiac PSV of 150 cm/s is normal. Retrograde common hepatic flow indicates celiac occlusion, but elevated PSV in the SMA is a direct measure of its own stenosis.

Question 161: What is a potential non-clinical career path for an RVT?

Ultrasound equipment sales (Correct answer)
Physical therapy assistant
Pharmaceutical research
Nursing management

Correct answer: Ultrasound equipment sales

A potential non-clinical career path for an RVT is in ultrasound equipment sales. Their deep understanding of ultrasound technology, clinical applications, and the needs of sonographers makes them ideal candidates to represent and sell imaging equipment. This role leverages their technical expertise in a business-oriented setting.

Question 162: What happens if an RVT fails to meet the renewal requirements?

The RVT must retake the initial exam
Certification becomes inactive (Correct answer)
Certification becomes permanently revoked
The RVT must pay additional fees but remains certified

Correct answer: Certification becomes inactive

If an RVT fails to meet the renewal requirements, such as completing the necessary CME credits within the five-year cycle, their certification becomes inactive. While not permanently revoked, an inactive certification means the individual cannot legally or professionally represent themselves as a certified RVT. Reinstatement typically requires fulfilling the missed requirements.

Question 163: A 68-year-old male is referred for a preoperative vein mapping of the right leg prior to coronary artery bypass grafting (CABG). Which of the following is the minimum acceptable diameter for the Greater Saphenous Vein (GSV) to be considered a suitable conduit?

2.0 mm (Correct answer)
1.5 mm
1.0 mm
3.5 mm

Correct answer: 2.0 mm

For a vein, most commonly the Greater Saphenous Vein, to be used as a conduit for bypass surgery, it must meet certain size criteria to ensure long-term patency. A diameter of 2.0 to 2.5 mm is generally considered the minimum acceptable size for a successful graft. Veins smaller than this have a higher risk of failure.

Question 164: During intraoperative TCD monitoring of a carotid endarterectomy, which finding should prompt the surgeon to insert an intraluminal shunt?

MCA mean velocity increase of 15% after clamping
Pulsatility index increase of 0.2 units
MCA mean velocity decrease of more than 50% from pre-clamp baseline (Correct answer)
Appearance of spectral broadening in the MCA waveform

Correct answer: MCA mean velocity decrease of more than 50% from pre-clamp baseline

A >50% drop in ipsilateral MCA mean velocity after carotid cross-clamping indicates inadequate collateral perfusion and cerebral ischemia risk. This threshold is widely used as the criterion for shunt placement to maintain cerebral blood flow during the endarterectomy.

Question 165: When performing mesenteric duplex scanning, which fasting PSV in the SMA most reliably identifies ≥70% stenosis?

≥200 cm/s
≥150 cm/s
≥275 cm/s (Correct answer)
≥350 cm/s

Correct answer: ≥275 cm/s

A fasting SMA PSV of 275 cm/s or greater has been validated as the threshold for detecting ≥70% stenosis in most published duplex criteria.

Question 166: What hemodynamic principle explains why a 50% diameter stenosis may not produce a resting pressure gradient but becomes hemodynamically significant during exercise?

At rest, collateral resistance exceeds stenosis resistance
Bernoulli's equation: pressure loss is proportional to flow velocity squared (Correct answer)
Flow velocity remains constant regardless of stenosis severity
Poiseuille's law: resistance increases with the square of radius reduction

Correct answer: Bernoulli's equation: pressure loss is proportional to flow velocity squared

Pressure loss across a stenosis is proportional to flow velocity squared (Bernoulli), so the increased flow demanded during exercise dramatically amplifies pressure gradient across a previously subcritical stenosis.

Question 167: Ultrasound-guided compression repair of a femoral pseudoaneurysm is MOST likely to fail or be contraindicated when the patient is:

Older than 70 years of age
Post-diagnostic (non-therapeutic) catheterization
Female with a body mass index under 25
Undergoing anticoagulation therapy (Correct answer)

Correct answer: Undergoing anticoagulation therapy

Anticoagulation significantly impairs the ability to thrombose the pseudoaneurysm sac during compression, making the procedure much less effective and requiring prolonged compression times. In anticoagulated patients, ultrasound-guided thrombin injection is the preferred alternative because it does not depend on the coagulation cascade.

Question 168: A patient is referred for a cerebrovascular ultrasound due to symptoms of vertebrobasilar insufficiency (VBI). Which of the following symptoms is LEAST likely to be associated with this condition?

Vertigo and dizziness
Drop attacks (sudden leg weakness)
Unilateral facial droop (Correct answer)
Bilateral vision loss (diplopia)

Correct answer: Unilateral facial droop

Vertebrobasilar insufficiency results from reduced blood flow to the posterior circulation of the brain. Symptoms typically involve structures supplied by the vertebral and basilar arteries, such as the cerebellum and brainstem, leading to vertigo, vision changes, and coordination issues. A unilateral facial droop is a classic symptom of anterior circulation stroke, often involving the middle cerebral artery territory, not typically isolated in VBI.

Question 169: Which of the following is considered a REQUIRED component of a complete vascular duplex examination report?

Clinical indication, technical description of findings, and diagnostic impression (Correct answer)
Insurance authorization code and billing CPT number
Comparison to the patient's prior imaging from outside institutions
The technologist's personal clinical impression and treatment recommendation

Correct answer: Clinical indication, technical description of findings, and diagnostic impression

A complete vascular report must include the reason the study was ordered (indication), a description of the vascular findings with supporting measurements, and a diagnostic conclusion or impression. These elements ensure the referring clinician has the information needed for clinical management.

Question 170: In the evaluation of a renal transplant by duplex ultrasound, which finding raises the concern for renal vein thrombosis?

Elevated PSV in the main renal artery exceeding 200 cm/s
Acceleration time greater than 70 ms in segmental arteries
Absent venous signal in interlobar veins only
Reversed diastolic flow (below baseline) in the intrarenal arteries (Correct answer)

Correct answer: Reversed diastolic flow (below baseline) in the intrarenal arteries

Renal vein thrombosis markedly raises downstream venous pressure, causing reversal of diastolic arterial flow as a characteristic duplex sign.

Question 171: A Doppler angle of 0° between the ultrasound beam and blood flow would result in:

Maximum Doppler shift (Correct answer)
Aliasing artifact
Mirror image artifact
Zero Doppler shift

Correct answer: Maximum Doppler shift

The cosine of 0° equals 1, making the Doppler equation yield maximum frequency shift when the beam is perfectly parallel to flow.

ARDMS Vascular Technology (VT) Exam

The ARDMS Vascular Technology (VT) exam awards the Registered Vascular Technologist (RVT) credential, assessing competency in vascular sonography including cerebrovascular, peripheral arterial, peripheral venous, and abdominal vascular testing.

170

Questions

180 min

Time Limit

79%

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