From the Guidelines
The best type of ultrasound to assess for intermittent claudication (vascular claudication) is Duplex Ultrasound, which combines Doppler ultrasound and B-mode imaging to evaluate blood flow and visualize the vascular anatomy 1. This non-invasive test is recommended as the initial imaging modality to diagnose and assess the severity of peripheral arterial disease (PAD), a common cause of vascular claudication. The test should be performed at rest and after exercise to assess changes in blood flow and ankle-brachial index (ABI) 1.
Key Benefits of Duplex Ultrasound
- High sensitivity and specificity: Duplex ultrasound has a sensitivity of 88% and specificity of 95% for detecting >50% stenosis 1.
- Non-invasive and radiation-free: Duplex ultrasound is a non-invasive, radiation-free, and contrast-free examination, making it a safe and preferred initial imaging modality 1.
- Dynamic assessment: Duplex ultrasound allows for dynamic assessment of blood flow and vascular anatomy, enabling the detection of borderline arterial lesions if initial findings are inconclusive 1.
Recommendations for Use
- Initial assessment: Duplex ultrasound is recommended as the initial imaging modality for patients with suspected PAD or vascular claudication 1.
- Post-exercise assessment: Duplex ultrasound should be performed after exercise to assess changes in blood flow and ABI, which can help diagnose PAD and assess its severity 1.
- Follow-up: Duplex ultrasound is recommended for follow-up of patients with PAD after revascularization to assess the effectiveness of treatment and detect any potential complications 1.
From the Research
Ultrasound Types for Assessing Intermittent Claudication
- Duplex ultrasound scanning (DUS) is a reliable and applicable method for assessing peripheral arterial disease (PAD) of the lower limb, including intermittent claudication (IC) 2.
- DUS has been shown to have good agreement with digital subtraction angiography (DSA) in most arterial segments, particularly in the supragenicular segments 2.
- Duplex sonography (DUS) has been compared to computed tomography angiography (CTA) in detecting occlusion and stenosis in PAD, with DUS showing good diagnostic concordance with DSA in the femoro-popliteal axis 3.
- The noninvasive vascular laboratory, including Doppler ultrasonography, can aid in the evaluation of patients with PAD and claudication 4.
- Innovations in vascular ultrasound, such as directional power Doppler ultrasound and contrast-enhanced ultrasound, can provide greater ability to visualize small vessels and assess vascular wall and lumen 5.
- A comparative analysis of Doppler ultrasound and multidetector CT angiography (MDCTA) for lower limb PAD diagnosis found that duplex ultrasound is a safe, cost-effective, and non-invasive alternative that complements the utility of MDCTA 6.
Diagnostic Accuracy of Ultrasound
- The sensitivity and specificity of Doppler ultrasonography in evaluating different arterial segments have been reported, with high values for the femoropopliteal segments and moderate values for the infrapopliteal segments 6.
- The agreement between Doppler ultrasonography and CT angiography has been evaluated using Cohen's kappa analysis, with very good agreement for the aortoiliac and femoropopliteal regions and moderate agreement for the infrapopliteal vessels 6.
Recommendations for Ultrasound Use
- DUS can be used as a non-invasive alternative to DSA for imaging of the distal crural arteries 2.
- DUS can be used in combination with other noninvasive tests to obtain information about the hemodynamic and functional severity of peripheral atherosclerosis in patients with claudication 4.
- High-quality DUS performed by well-trained operators may represent a good alternative to CTA in patients undergoing endovascular revascularization 3.