Duplex US Imaging of the Lower Extremity Venous System (Lecture 6) Flashcards
What is the purpose of Superficial Veins?
Regulate body temperature
What is the role of perforators?
Move blood from the superficial veins to the deep veins
What is Virchow’s Triad?
Venous stasis, hypercoaguability, vessel wall injury
Where do DVTs commonly begin?
Soleal sinus vein
What are other risk factors for VTE?
COIT OFO
Cancer
Obesity
Immobility
Trauma/Surgery
Hormones or pregnancy
Factor V Leiden
Other thrombophilia
What are the signs and symptoms of venous thromboembolism?
Venous obstruction, inflammation, and embolization of thrombi
What are symptoms consistent with PE that a patient may show during a VTE?
Tachypnea, chest pain, tachycardia
A negative d-dimer is a low or high specific test?
Very highly specific
What is a D-Dimer?
Breakdown product of fibrin which will be elevated in the presence of DVT
What is the termination of the GSV into the CFV called?
Saphenofemoral junction
The terminus of the Small Saphenous Vein into the Popliteal Vein is known as which junction?
Saphenopopliteal Junction
What is a Giacomini vein?
When the SSV bypasses the popliteal vein and continues up the posterior thigh
What is the one of the major storage areas for blood in the calf?
Soleal sinus vein
When would you image above the groin for a lower extremity DVT scan?
Unless there is clinical indication to suggest involvement of the iliac veins or the IVC
What 5 characteristics should Venous Doppler signals display?
PPAPU
- Present Spontanous Doppler signals within all major vessels
- Phasic with respiration
- Augmented flow with compression
- Promixal compression should never cease the signal
- Unidirectional towards the heart
If you have a thrombosed vein, what should your doppler look like?
Colour flow and spectral waveforms will be absent, imcompressible vein
If you have a distal thrombosis, what should your doppler look like?
Vein is compressible but when doing distal compression, no colour flow is observed or no augmentation appears in spectral
If you have a proximal thrombosis, what should your doppler look like?
Vein compresses but lacks respiratory phasicity and does not cease with proximal compression or valsalva (called continuous flow) - basically just looks like continous fuzz below baseline
Arteriovenous fistulae can be associated with what kind of flow?
Unilateral pulsatile venous flow
What type of flow in LEV is abnormal?
Retrograde flow
What is May-Thurner syndrome?
Compression of the left common iliac vein by the right common iliac artery
What is Phlegmasia alba dolens?
Milk leg, marked swelling of lower extremity, pain, pitting edema, blanching - but no ischemia present
What is Phelegmasia cerulean dolens?
Massive swelling and cyanosis, severe pain
What are nonvascular findings of a DVT study?
Hematomas, cysts, edema, abscesses, enlarged lymph nodes, and tumours
What can rupture behind the knee and appear as a fluid collection that dissects along the fascial planes in the calf?
Pop fossa cyst (Baker’s cyst)
What are some vascular findings during a DVT study?
Aneurysm, pseudoaneurysms, arteriovenous fistulas, or significant arterial disease
What is the primary treatment of DVTs?
Anticoagulation medication
