Chapter 17: Duplex Ultrasound Imaging of the Lower Extremity Venous System Flashcards
(130 cards)
Newly formed clotted blood within a vein, generally less than 14 days old
acute thrombus
residual material present within a vein for a period of several weeks or months; also called chronic change, scarring
chronic post-thrombotic changes
a vein that is the companion vessel to an artery and travels deep to the muscular fascia and lies within the deep muscular compartments of the leg
deep vein
a small vein that connects the deep and superficial venous systems
perforating vein
a vein that is superficial to the muscular fascia and the muscular compartments of the leg; travels within superficial fascial compartments; has no corresponding companion artery
superficial vein
an inward projection of the intimal layer of a vein wall producing two semilunar leaflets, which present the retrograde movement of blood flow
valve
Well’s criteria high probabality of DVT
more than 3 points
Well’s criteria intermediate probability of DVT
1-2 points
Well’s criteria low probability of DVT
0 points
thrombus poorly attached to vein wall; may be free floating
acute thrombus
Spectral and color Doppler signals complete thrombus
none
thrombus fully attached to vein wall
chronic post-thrombotic changes
veins will partially compress but not able to completely coapt walls
partial nonocclusive thrombus
Venous ultrasound used to assess three main things:
presence of absence of thrombus
appearance of thrombus
competence of contained valves
3 main categories of veins that can be imaged:
deep veins
superficial veins
perforating veins
main conduit for blood returning to the heart
deep veins
travel close to skin, superficial to muscle
superficial veins
What is the purpose of superficial veins?
get blood near skin to help regulate body temperature
small veins that connect deep veins with superficial veins
perforating veins
move blood from superficial veins to deep veins where blood can be pumped back to heart by muscular contractions
perforating veins
Leading cause of preventable death
venous thromboembolism
most common mechanisms for the formation of venous thrombosis
Virchow Triad
Virchow Triad
venous stasis
vessel wall injury
hypercoaguability
allows for increased exposure of clotting factor occurs in immobility
venous stasis