This document provides information on performing and interpreting arterial Doppler ultrasonography of the lower limbs. It discusses the anatomy of the lower extremity arteries, scanning technique, pathologies that can be identified including stenosis grading and waveforms, and recommendations for report writing. The key steps are to optimize grayscale and color Doppler parameters, examine color aliasing/disturbances with pulse Doppler, and evaluate waveforms and velocities to diagnose conditions like atherosclerosis, thrombosis, aneurysms and arterial stenoses.

1. Dr. KAZIM ULLAH
RESIDENT RADIOLOGY
CMH ABBOTTABAD
ARTERIAL DOPPLER LOWER LIMBS

2. SEQUENCE
Introduction
Anatomy
Technique
Pathologies
Reporting

3. INTRODUCTION
 Ultrasonography can diagnose stenosis through the direct
visualization of plaques and through the analysis of the Doppler
waveforms in stenotic and post stenotic arteries.
 To perform Doppler ultrasonography of the lower extremity arteries,
the operator should be familiar with the arterial anatomy of the
lower extremities, basic scanning techniques, and the parameters
used in color and pulsed-wave Doppler ultrasonography

4. ANATOMY

5. ULTRASOUND TECHNIQUE
 5 MHz Linear Transducer(Range 3- 10 MHZ)
 The transducer is placed over an artery for transverse scanning,
and then is rotated 90° for longitudinal scanning
 The artery should be scanned on a longitudinal plane as long as
possible
 Optimize Gray Scale And Color Doppler Parameters
 Adjust Pulse Repetition Frequency(PRF) To Detect Hemodynamic
Disturbances
 Perform Pulse Doppler In Regions Of Color Aliasing/distubance

6. ULTRASOUND TECHNIQUE

7. ARTERIES SCANNED IN DOPPLER
ULTRASOUND OF LOWER LIMBS
 Common femoral artery
 Profunda femoris artery
 Superficial femoral artery
 Popliteal artery
 Tibio-peroneal trunk
 Posterior tibial artery
 Peroneal artery
 Anterior tibial artery
 Dorsalis pedis artery

8. ULTRASOUND ANATOMY OF THE LOWER
EXTREMITY ARTERIES
 Arteries can be differentiated from veins on US by several
characteristics.
 Arteries are round in transverse images, while veins are somewhat oval.
 Arteries are smaller than veins.
 Arteries have visible walls and sometimes have calcified plaques on the
walls.
 When the vessels are compressed by the transducer, arteries are
partially compressed, while veins are completely collapsed

9. ULTRASOUND ANATOMY OF THE LOWER
EXTREMITY ARTERIES

10. ULTRASOUND ANATOMY OF THE LOWER
EXTREMITY ARTERIES

11. ULTRASOUND ANATOMY OF THE LOWER
EXTREMITY ARTERIES

12. ULTRASOUND ANATOMY OF THE LOWER
EXTREMITY ARTERIES

13. PERIPHERAL ARTERIAL DISEASE
 Narrowing or blockage of the vessels that carry blood from heart to the
legs
 RISK FACTORS
 Diabetes
 Smoking
 Advancing age
 Hypercholesterolemia
 Hypertension
 Obesity

14. CAUSES OF LOWER LIMB ARTERIAL DISEASES
 Atherosclerosis
 Thrombosis/ embolism
 Aneurysm
 Intimal dissection
 Pseudo aneurysm
 AV fistula
 Arteritis
 Entrapment syndrome
 Cystic adventitial disease

15.  Waveform shape
 Peak systolic velocity
 Spectral window
COMPONENTS TO LOOK FOR IN STENOSIS

16. DOPPLER WAVEFORMS
 Doppler waveforms refer to the morphology of pulsatile blood flow
velocity tracings on spectral Doppler ultrasound.
 Waveforms differ by the vascular bed (peripheral, cerebrovascular, and
visceral circulations) and the presence of disease.
 Most authorities describe three types based on the number of phases of
flow in each cardiac cycle

17. TRIPHASIC FLOW
 Doppler spectrum of normal lower extremity arteries
 having three phases, due to crossing the zero flow baseline twice in
each cardiac cycle
 systolic forward flow
 early diastolic flow reversal (below zero velocity baseline)
 late diastolic forward flow (slower than in systole)

18. NORMAL PERIPHERAL ARTERIAL WAVEFORM

19. BIPHASIC FLOW

20. MONOPHASIC FLOW

21. PEAK SYSTOLIC VELOCITY
 Peak systolic velocity (PSV) is an index measured in spectral Doppler
ultrasound. On a Doppler waveform, the peak systolic velocity
corresponds to each tall “peak” in the spectrum window.

22. PEAK SYSTOLIC VELOCITY

23. PEAK SYSTOLIC VELOCITY
 Peak systolic velocity (PSV) is an index measured in spectral Doppler
ultrasound. On a Doppler waveform, the peak systolic velocity
corresponds to each tall “peak” in the spectrum window.

24. SPECTRAL WINDOW
 In normal straight vessels, blood flows are mostly in parallel and of
constant velocities. Thus, Doppler spectral wave-forms appear
concentrated and have no low velocity blood flow, thereby forming a so-
called spectral window due to the absence of Doppler signal below the
spectrum.
 When blood flow velocity is non-parallel flow, a wide range of blood flow
velocities can be recorded simultaneously, resulting in spectral
broadening of Doppler spectral waveforms.
 When low velocity turbulence arises in blood vessels, the turbulent
signals will appear in the original spectral window, causing a
disappearance or decrease in the spectral window, which is called
spectral fill-in

25. SPECTRAL WINDOW

26. GRADING OF ARTERIAL STENOSIS

27. GRADING OF ARTERIAL STENOSIS

28. CRITERIA FOR THE CLASSIFICATION OF
PERIPHERAL ARTERIAL STENOSIS
 1-19% diameter reduction - Minimal disease
 20-49% diameter reduction - Moderate disease
 50-99% diameter reduction - Significant disease
 Occlusion

29.  Mild spectral broadening>1-29
%
 Increase in peak systolic
velocity (VR<1.5)
 Normal waveform.
1-19% DIAMETER REDUCTION - MINIMAL DISEASE

30.  Spectral broadening>30-99 %
 Increase in peak systolic
velocity(VR 1.5-2)
 Reverse flow component
present
20-49% DIAMETER REDUCTION - MODERATE
DISEASE

31. • Monophasic waveform
• Loss of reverse flow
component (Mono-phasic flow)
• Marked spectral broadening
• 100% increase in systolic
velocity(VR >2)
• Post-stenotic turbulence.
50-99% DIAMETER REDUCTION. SIGNIFICANT
DISEASE

32.  Absence of flow in occlusion
 Proximal flow is high resistance
 Distal flow is low resistance
with tardus pattern
 Collateral flow
OCCLUSION

33.  Low velocity monophasic
waveforms
 Lose triphasic character
 Tardus parvus appearance
(prolong systolic acceleration
and small systolic amplitude)
 Low resistance related to
degree of ischemia
COLLATERAL FLOW

34. COLLATERALS

35. THROMBOSIS OR EMBOLISM

36. ANEURYSM

37. INTIMAL DISSECTION

38. REPORT WRITING
 Arteries of lower limbs shows normal tri-phasic flow
 No atherosclerotic plaques are seen in major arteries of both lower limbs
 The blood flow velocities are with in normal range in all major arteries
and their main branches in both lower limbs down to dorsalis pedis
arteries in feet

39. THANK YOU