From the Guidelines
Doppler ultrasound is indicated to assess arterial flow in the lower extremities in patients with peripheral artery disease (PAD) who have undergone revascularization and have new signs or symptoms.
Indications for Doppler Ultrasound
- The assessment of lower extremity PAD location and severity 1
- To follow lower extremity PAD progression 1
- To provide quantitative follow-up after revascularization procedures 1
- To identify the location, degree, and extent of stenosis to the level of the knee 1
- As a surveillance tool for arterial bypass grafts with established criteria for graft stenosis and thresholds for reintervention 1
Benefits of Doppler Ultrasound
- Provides an accurate assessment of lower extremity PAD location and severity 1
- Useful to assess lower extremity PAD anatomy, severity, and progression 1
- Can provide localizing information in patients with poorly compressible arteries 1
- Can provide quantitative data after successful lower extremity revascularization 1
Limitations of Doppler Ultrasound
- Limited sonographic windows resulting in nondiagnostic segments of the aorta and iliac arteries 1
- May underestimate the extent of disease when multiple “tandem” stenotic segments are present in series 1
- Patient discomfort during the procedure may limit adequate visualization 1
- Less accurate for detecting significant stenoses and for preoperative planning compared to CE-MRA or CTA 1
From the Research
Indications for Doppler Ultrasound
The indication for a Doppler ultrasound to assess arterial flow in the lower extremities includes:
- Diagnosing stenosis through the direct visualization of plaques and through the analysis of the Doppler waveforms in stenotic and poststenotic arteries 2
- Evaluating peripheral arterial disease (PAD) and bypass grafts in lower limbs 3
- Assessing the functional state of the peripheral arterial circulation, including blood flow velocity and poststenotic arterial pressure 4
- Estimating blood volume flow of the lower extremities and establishing a quantitative relationship between volume flow and pulsatility index (PI) in both healthy subjects and patients with PAD 5
- Diagnosing lower extremity peripheral arterial disease, particularly in the elderly where claudication is an unreliable sign 6
Key Applications
Doppler ultrasound is a valuable technique for:
- Visualizing arterial anatomy and scanning guidelines for the lower extremity arteries 2
- Overcoming pitfalls in traditional Doppler ultrasonography using B-flow imaging 3
- Evaluating flow patterns, determining transit time of velocity wave forms, and imaging the arterial circulation 4
- Providing a noninvasive means of arterial visualization in the lower extremities 6