Physiology
What is the purpose of vein mapping?
to identify and measure veins for bypass or graft harvest
True or false: PE from GSV clot is thought to be fatal.
False
Which artery connects the ICA and PCA?
Posterior communicating artery
This sign represents marked narrowing of the artery with variable ratio and tardus parvus waveform.
String Sign
How do you calculate Carotid ratio to grade the degree of stenosis?
PSV ICA/PSV CCA (mid or distal)
Towards the transducer
White scarred skin surrounded by dilated capillaries.
Atrophie Blanche
The “Cleopatra’s eye” refers to what structure?
Sonographic appearance of GSV between superficial and deep fascia.
What is the direction of blood flow in the VA and BA when performing TCD?
Away from the transducer; below the baseline
Why is angle correct not required on venous duplex studies?
It does not provide any important clinical information.
In a normal CVI study, blood flow should move in this direction after distal augmentation.
toward the heart (no reflux/antegrade flow)
List three non-surgical treatments for CVI.
Compression, leg elevation, exercise, weight control.
Name 3 DVT treatments
Anticoagulants
Thrombolytics
IVC filter (if high PE risk).
Reflux is demonstrated as flow reversal lasting greater than 1 second.
What is the pressure, flow and resistance relationship and what is the name of this relationship?
Poiseuille’s law:
Pressure gradient = Flow × Resistance
What does the Lindegaard ratio signify?
It helps signify if high velocity in MCA is cause by a true vasospasm or due to other physiologic conditions.
If valves are damaged from prior DVTs, it can cause this kind of disease process.
Secondary CVI
The cephalic and basilic vein join together where to form what vein?
Antecubital fossa; median cubital vein
While performing upper venous ultrasound, you notice an occlusive blood clot in the left mid brachial vein. What do you expect your spectral trace to look like?
Absent - no spectral trace as the clot is occlusive.
List 4 clinical applications of TCD
Detect vasospasm
Monitor for emboli
Evaluate stenosis, AVM, aneurysm
Confirm brain death
Intraoperative monitoring
Screen sickle cell disease
What is the direction of blood flow at the ICA siphon when assessing with TCD, respective of the different segments of the siphon.
Can be towards (parasellar), bidirectional (genu), or away (supraclinoid segment) depending on where you place the sample gate
After a subarachnoid hemorrhage, this condition causes narrowing of cerebral arteries and can lead to stroke
What is cerebral vasospasm?
List the name of all arteries (including all segments) that make up the circle of willis.
anterior communicating artery
anterior cerebral artery segment 1 and 2
middle cerebral artery
terminal internal carotid artery
posterior cerebral artery segment 1 and 2
basilar artery
vertebral artery
posterior communicating artery
While performing a carotid Doppler, you find PSV in distal CCA is 100 cm/s and PSV of proximal ICA is 200 cm/s. How would you grade the stenosis and what do you expect to see on ultrasound (B-more and color)
This is 50-69% stenosis; expect so see visible plaque, and color aliasing at the stenosis
This is a clinical condition caused by obstruction or compression of the superior vena cava or right atrium
Superior vena cava syndrome