Leg DVT Ultrasound CAITLIN GARDINER The Role of Ultrasound To exclude deep vein thrombosis as a...
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Leg DVT Ultrasound CAITLIN GARDINER
Leg DVT Ultrasound CAITLIN GARDINER The Role of Ultrasound To exclude deep vein thrombosis as a cause for pain and swelling in the lower limb Screening
The Role of Ultrasound To exclude deep vein thrombosis as a
cause for pain and swelling in the lower limb Screening tool in
post operative surgery Known pulmonary embolus, (?location of their
embolus) (1)
Slide 4
The Principal of DVT US Non compressibility Filling defects
with colour Doppler Focal tenderness (acute thrombus will be
hypoechoic and difficult to see on B-mode without increasing gain)
Hyperechoic lesion within lumen of the vein
Slide 5
Probe and Pre-set selection Mid frequency linear probe (5-8MHZ)
Have access to curvi-linear probe Low PRF (velocity) colour / power
/ Doppler settings with low wall filter when assessing veins with
low velocity flow (2) Select the appropriate vascular setting on
the US machine
Slide 6
Patient Set Up Supine, erect or seated in a reclined position
to allow access to the groin. Venous distension is useful for
assessing calf veins The patient must remove their pants as
scanning commences at the groin (2) Important to be conservative
and profession. A gown or blanket may be helpful Be conscious that
a large amount of the patients are older, post surgery or have
limited mobility
Slide 7
Anatomy All images extracted from www.ultrasoundpaedia.com
Slide 8
Common Femoral & (Superficial) Femoral Veins Patient supine
with slight external rotation of affected leg In transverse, high
in the groin crease, locate the CFA & CFV at the
sapheno-femoral junction. Compress the vein. Continue to follow the
vein sequentially compressing down to the distal thigh (3)
Slide 9
Slide 10
Slide 11
Popliteal vein Seat the patient on the side of the bed to help
dilate the veins for easier visualisation. Place the probe
transversely at the knee crease in the popliteal fossa. Compress
the popliteal vein throughout the popliteal fossa (3)
Slide 12
Slide 13
Calf Veins Patient still seated on bed Transversely, with the
toe of the probe on the medial edge of the mid tibia, locate the
paired posterior tibial and peroneal veins Assess their
compressibility along their length. Alternatively, in longitudinal,
use colour Doppler to confirm their patency (3)
Slide 14
Slide 15
Basic Hard Copy Images A leg DVT series should include the
following minimum images: CFV: pre/post compression Proffunda
femoris SFV proximal TS: pre/post compression SFV proximal LS: with
colour Doppler SFV distal TS: pre/post compression SFV distal LS:
with colour Doppler POPV TS: pre/post compression POPV LS: with
colour Doppler Posterior tibial veins LS colour Doppler Peroneal
veins LS colour Doppler Sapheno-femoral-junction (1)
Slide 16
Differential Diagnosis Common differential diagnoses
identifiable on ultrasound are: Bakers cyst
(semi-membranosis-gastrocnemial bursa) in the medial popliteal
fossa. Superficial venous thrombosis of varices and the long/short
saphenous veins. Calf muscle tears (2,3)
Slide 17
Limitations Obese patients, or those with severe oedema
Patients with open wounds/sutures/bandages Patients with a low pain
threshold (2)
Slide 18
Thank you
Slide 19
References (1) ASUM, 2007. Short Syllabus, DVT.
www.asum.com.auwww.asum.com.au (2) Rumack C, Wilson R, Charboneau W
and Levine D, 2010. Diagnostic Ultrasound 2-Volume Set, 4 th
Edition. Mosby. (3) Thrush A and Hartshorne T, 2009. Vascular
Ultrasound: How, Why and When, 3e. Churchhill Livingstone. (4)
Weinberg I, 2012. DVT Ultrasound Protocol. Vascular Medicine.
www.angiologist.com