Ch 5 Duplex Imaging of LEVs

Question 1

Differentiate b/w acute + chronic thrombus?

Answer 1

Acute: blood clot for <14 days
Chronic: blood clot for several weeks or months

Question 2

Deep veins accompany what?

Answer 2

An artery, usually of the same name

Question 3

Is a DVT more or less likely to become dislodged?

Answer 3

More, due to muscle contractions

(the thrombus in deep veins is also larger + more life threatening than in superficial veins)

Question 4

Do superficial veins have an accompanying artery?

Answer 4

No

Question 5

Purpose of superficial veins?

Answer 5

Helps regulate body temperature

Question 6

Emboli from superficial or deep veins is less likely to cause a PE?

Answer 6

Superficial, b/c they are smaller + not contracted by surrounding muscles

Question 7

What is the role of perforators?

Answer 7

-They are small veins that connect deep veins with superficial veins

-Role is to move blood from the superficial veins to the deep veins

Question 8

What is Virchow’s triad?

Answer 8

-Primary mechanism for the formation of venous thrombosis

-Consists of: venous stasis, vessel wall injury + a hypercoagulable state

Question 9

DVTs m/c begin in the ___ ___ veins?

Answer 9

Soleal sinus veins in calf, b/c they have slower flow

Question 10

List 3 signs/symptoms of a VTE?

Answer 10

Venous obstruction, inflammation + embolization of thrombi

Question 11

List 3 signs/symptoms of a PE?

Answer 11

Tachypnea, chest pain, tachycardia

Question 12

What is the m/c used tool for risk stratification?

Answer 12

Well’s criteria

Question 13

What is D-Dimer?

Answer 13

Breakdown product of fibrin which will be elevated in presence of DVT

(a negative d-dimer is safe to exclude DVT)

Question 14

What position should the bed be in during LEV exam?

Answer 14

Reverse Trendelenburg (helps blood pool in legs)

Question 15

What probes are used during a LEV exam?

Answer 15

5-10 MHz: FV, PV, calf veins

10-18 MHz: for superficial veins

2-5 MHz: IVC + iliac veins (or heavier pt’s)

Question 16

LEV compressions are done down the leg in TRV every how many cm’s?

Answer 16

Every 2-3cm down entire length of leg

(SFJ, FV prox/mid/distal, PopV, SPJ + calf veins)

Question 17

PW is performed in which LEVs?

Answer 17

CFV, FV + PopV

Question 18

In 1/3 legs, the FV may be a ___ system?

Answer 18

Bifid system (meaning the FV is duplicated)

Question 19

In the case of a pt with a bifid system + a DVT, is it common for one FV to be patent + the other to be thrombosed?

Answer 19

Yes!

Question 20

At the ___/___ ___, the FV travels deep into the muscles of the thigh?

Answer 20

Adductor/hunter’s canal

(might see on test)

Question 21

Distal to the adductor canal is the ___ vein?

Answer 21

Popliteal (this is the main drainage for blood leaving the calf)

Question 22

What other vein can be bifid, other than the FV?

Answer 22

The PopV, although less common

Question 23

What structures are seen in the upper + lower popliteal fossa?

Answer 23

Upper: PopV + PopA

Lower: Tributaries such as gastroc veins + SSV

Question 24

What is the giacomini vein?

Answer 24

Cranial extension of the SSV, it communicates with the GSV

Question 25

A major storage area for blood in the calf is a network of veins called?

Answer 25

The soleal sinus veins

Question 26

The soleal veins drain into the ___ + ___ veins?

Answer 26

Posterior tibial + peroneal veins

Question 27

List 5 venous doppler characteristics that represent a thrombus free vein?

Answer 27

-Spontaneous doppler signals
-Phasic flow with respiration
-Leg compression should augment flow
-Doppler signals should cease with proximal compression or valsalva
-Doppler signal should be unidirectional, towards heart

Question 28

SF of a thrombus?

Answer 28

-Echogenic material in lumen, causing restriction of complete compression
-Vein will enlarge

(acute thrombus can be hard to see, almost invisible)

Question 29

SF of chronic post DVT?

Answer 29

-Echogenic material may persist (is mostly collagen)
-Material is now dense, rigid with irregular borders + attached to vessel wall
-Walls may be thickened

Question 30

What would a DVT look like on doppler?

Answer 30

Thrombosed vein: absent CD + spectral waveforms (vein won’t compress)

Distal thrombosis: vein can compress, but when there is a distal augmentation there is a lack of a waveform

Prox thrombosis: vein can compress, but lacks respiratory phasicity (known as continuous flow)

Question 31

What is unilateral + bilateral pulsatile venous flow associated with?

Answer 31

Uni: arteriovenous fistulae

Bi: venous hypertension

(there should not be pulsatile or retrograde flow in veins)

Question 32

What is May-Thurner syndrome?

Answer 32

Compression of the left CIV by the right CIA

Question 33

What is Phlegmasia Alba Dolens?

Answer 33

-Marked swelling of lower extremity, pain, pitting edema + blanching (no ischemia)

-Is called milk leg!!
-Can be associated with pregnancy

Question 34

What is Phlegmasia Cerulean Dolens?

Answer 34

-Similar to Phlegmasia Alba Dolens, except more extensive
-Massive swelling, cyanosis + severe pain

Question 35

List common incidental findings during a LEV exam?

Answer 35

-M/c hematomas
-Cysts, edema, abscesses, enlarged lymph nodes + tumors
-Pop fossa cysts (baker’s cysts), these can rupture
-Aneurysms, etc

Question 36

Primary treatment of acute DVT?

Answer 36

Anticoagulation therapy (heparin, then warfarin)