An arterial duplex ultrasound combines greyscale and Doppler imaging to assess blood flow in leg arteries. It can help investigate a suitable peripheral arterial disease or circulation question. A cold, pale or blue limb, sudden severe limb pain, weakness or loss of feeling needs emergency assessment immediately.
Duplex ultrasound provides non-invasive information about blood flow and narrowing in the arteries assessed. Evidence reviews describe its role in symptomatic lower-limb peripheral arterial disease, while also recognising that some patients need other imaging or specialist assessment depending on the clinical question.[1]
I use arterial imaging as one part of a wider cardiovascular assessment. The scan does not replace urgent treatment for symptoms of acute limb ischaemia.
Written & reviewed by
Dr George Xynopoulos
Consultant Physician and Cardiologist, GMC registered
What I Assess With a Arterial Duplex Ultrasound Scan
The scan assesses accessible arteries in the leg and Doppler waveforms at points relevant to the request. It may help describe narrowed or blocked segments, but it does not test every cause of walking pain, numbness or leg symptoms.
| Part of the assessment | What the scan can help show |
|---|---|
| Leg arteries | Visible artery anatomy and flow in the segments assessed |
| Doppler waveforms | Direction and character of blood flow at selected points |
| Symptom distribution | Findings interpreted against the part of the leg and symptoms reported |
Preparation Before Your Appointment
No fasting or bladder preparation is usually needed. Wear loose clothing or shorts that allow access to the leg. Continue prescribed medicines unless a clinician who knows your case gives different advice.
Preparation summary: No special preparation. Wear loose trousers or shorts that allow access to the leg; continue medicines unless advised otherwise.
What Happens During the Scan
You lie comfortably while gel and an external probe are used along the leg. The sonographer may measure Doppler flow at different levels and may ask you to keep still briefly while recordings are made.
- Bring any relevant referral letter, previous scan report or clinic letter if you have one.
- Tell the team about new symptoms, recent surgery, hospital admissions and medicines that affect blood clotting.
- Ask if you are unsure whether this is the right examination before the scan begins.
How I Use the Result in Your Care Pathway
I consider an arterial duplex result alongside symptoms, pulse findings, cardiovascular risk and other tests where needed. If the result or symptoms point to a condition that needs specialist review, I will explain the safest next step.
When to Seek Urgent Medical Help
Call 999 for sudden severe leg pain with a cold, pale, blue or numb foot or leg; new weakness; loss of sensation; or rapid deterioration. These symptoms can need emergency vascular assessment.
A routine ultrasound booking is not emergency care. If symptoms are sudden, severe, worsening, or include chest pain, breathing difficulty, collapse, new neurological symptoms or a cold painful limb, call 999 or attend A&E.
What to Expect at Your Appointment
Check the clinical question
Before your appointment, I want the team to understand your symptoms, relevant history and the part of the circulation that needs assessment.
Follow the preparation advice
Wear loose trousers or shorts that allow access to the leg; continue medicines unless advised otherwise.
Have your duplex ultrasound
A sonographer uses an external probe, greyscale imaging and Doppler assessment of blood flow where relevant.
Plan the next step
Your report is considered alongside your symptoms and clinical history so that I can advise on suitable follow-up or urgent care.
Frequently Asked Questions
References
- [1]Collins R, et al. A systematic review of duplex ultrasound, MRA and CTA for symptomatic lower-limb peripheral arterial disease. Health Technology Assessment. 2007. DOI: 10.3310/hta11200.
- [2]NICE. Peripheral arterial disease: diagnosis and management (CG147).
- [3]European Society for Vascular Surgery. 2024 clinical practice guidelines on peripheral arterial disease.
Related Services at Victoria Medical