What does a non‑visible peroneal artery on arterial duplex ultrasound indicate?

Non-Visible Peroneal Artery on Arterial Duplex Ultrasound

A non-visible peroneal artery on duplex ultrasound most commonly indicates either complete occlusion of the vessel, severe calcification obscuring flow signals, or technical limitations preventing adequate visualization—each scenario requires immediate cross-sectional imaging (CTA or MRA) to definitively characterize the anatomy and plan revascularization if clinically indicated. 1

Primary Diagnostic Considerations

When the peroneal artery cannot be visualized on duplex ultrasound, three main possibilities exist:

1. Complete Arterial Occlusion

• Absence of detectable flow signals typically indicates thrombotic occlusion, particularly in patients with advanced peripheral arterial disease (PAD) or critical limb-threatening ischemia (CLTI). 2
• This finding is clinically significant because the peroneal artery often serves as a critical collateral pathway when the anterior and posterior tibial arteries are diseased. 2

2. Dense Arterial Calcification

• Heavy calcification can completely obscure duplex flow signals, especially when flow velocity is slow, creating a false impression of vessel absence when the artery may actually be patent but severely diseased. 1
• This technical limitation is particularly common in patients with diabetes and chronic kidney disease. 1, 2

3. Technical and Anatomic Limitations

• Duplex ultrasound has inherent limitations for infrageniculate vessel assessment, with only moderate agreement (κ = 0.4–0.6) with angiography for tibio-peroneal trunk and peroneal artery evaluation. 2
• Deep vessel location, obesity, edema, or inadequate sonographic windows may prevent adequate visualization even when vessels are patent. 1

Immediate Next Steps

Obtain Definitive Cross-Sectional Imaging

• Order CTA of bilateral lower extremities with runoff as the definitive imaging modality to precisely localize stenosis/occlusion from the aorta to the pedal vessels and determine technical feasibility of revascularization. 1, 2
• CTA provides complete anatomic detail in a single study, enabling accurate identification of location and severity of disease. 3
• MRA is an acceptable alternative with 90–100% sensitivity and specificity for detecting ≥50% stenosis, particularly useful in patients with renal insufficiency where non-contrast techniques can be employed. 1, 2

Clinical Assessment for CLTI

• Evaluate immediately for rest pain, tissue loss, or gangrene—these constitute CLTI and represent Class I indications for urgent revascularization. 2
• Measure ankle-brachial index (ABI), recognizing that ABI may underestimate disease severity in patients with heavily calcified vessels. 2
• Document claudication distance, characteristics of rest pain, and functional limitations to guide treatment decisions. 2

Why Duplex Alone Is Insufficient

• Duplex ultrasound cannot reliably provide the anatomic detail required for tibial-level treatment planning, whether for distal bypass or endovascular intervention. 1, 2
• The ACC/AHA guidelines establish that duplex has 90–95% sensitivity and specificity for stenoses >50% from iliac to popliteal arteries, but accuracy diminishes significantly below the knee. 1
• Multiple sequential lesions further reduce duplex accuracy, necessitating definitive anatomic imaging for comprehensive assessment. 1, 2

Management Algorithm Based on Imaging Results

If CTA/MRA Confirms Occlusion with CLTI Present:

• Revascularization is a Class I indication when rest pain, tissue loss, or gangrene is present. 2
• Endovascular therapy is generally preferred when anatomy is suitable due to lower peri-operative morbidity. 2
• Surgical tibial bypass requires high-quality pre-operative imaging to identify suitable target vessels. 2

If CTA/MRA Shows Patent but Diseased Vessel:

• The initial duplex finding was likely due to calcification or technical factors rather than true occlusion. 1
• Treatment decisions depend on symptom severity and overall disease burden. 2

If Lifestyle-Limiting Claudication Without CLTI:

• Revascularization is warranted only after failure of supervised exercise therapy and optimal medical management. 2

Cardiovascular Risk Modification (Mandatory for All PAD Patients)

• Initiate high-intensity statin therapy irrespective of baseline lipid levels. 2
• Prescribe antiplatelet therapy (aspirin or clopidogrel) for cardiovascular event prevention. 2
• Optimize blood pressure control and enforce smoking cessation, as peripheral disease reflects systemic atherosclerosis. 2

Common Pitfalls to Avoid

• Never rely on duplex ultrasound alone for treatment planning when infrageniculate disease is suspected—the limited spatial resolution and technical challenges make it inadequate as a sole imaging modality for distal vessels. 1, 2
• Do not assume vessel absence based solely on non-visualization—calcification and technical factors frequently produce false-negative results. 1
• Avoid delaying cross-sectional imaging in patients with clinical signs of CLTI—tissue loss and gangrene require urgent anatomic definition for revascularization planning. 2
• Remember that slow flow in severely diseased vessels may be below the detection threshold of duplex, particularly in the setting of poor inflow. 1