A vascular duplex ultrasound tells me more in 20 minutes than an MRI report three pages long. It is non-invasive, real-time, and gives blood flow information no other test can.
Written by Dr Rahul Agarwal, Consultant Vascular & Endovascular Surgeon
CARE Hospitals, Banjara Hills, Hyderabad
When you attend a vascular surgery clinic, one of the first investigations ordered is a duplex ultrasound. It is the workhorse of vascular diagnosis — non-invasive, radiation-free, real-time, and extraordinarily informative in the right hands.
🦠 What Is It?
Duplex ultrasound combines B-mode imaging (vessel structure, plaques, clots) with Doppler (blood flow velocity and direction). Together they give a dynamic picture of blood flow in any vessel. Colour Doppler adds colour-coded flow visualisation on-screen.
📊 What It Diagnoses
- Peripheral artery disease — location and severity of leg blockages
- Carotid stenosis — degree of plaque narrowing and embolism risk
- DVT — detects blood clots in deep leg veins with high accuracy
- Varicose veins — maps incompetent valves to guide ablation planning
- Aortic aneurysm screening — quick, reliable diameter measurement
- AV fistula assessment — flow measurement, stenosis detection
- Bypass graft surveillance — detects stenosis before occlusion
🏥 What to Expect
Gel applied to skin, probe moved over the area. You may hear pulsing Doppler sounds. Painless, no radiation, no needles. Takes 20–45 minutes depending on the area.
❓ FAQ
Do I also need a CT angiogram if I have a duplex?
For many conditions, duplex alone is sufficient. CT angiography is added when precise anatomical detail is needed for surgical or endovascular planning (e.g., EVAR, complex bypass). Your surgeon will advise.
Can any ultrasound machine do this?
Vascular duplex requires dedicated equipment and an experienced vascular sonographer. Quality varies enormously. Always use a dedicated vascular laboratory or vascular surgery centre.
💡 Key Insight: Vascular ultrasound is the ECG of vascular surgery — first-line, immediate, actionable. In our vascular OPD at CARE Hospital, almost every patient have a free ultrasound screening.
📖 Related: PAD Guide | DVT Guide | The Complete Guide
About the Author 🧑🏻⚕️
Dr Rahul Agarwal is a Consultant Vascular & Endovascular Surgeon at CARE Hospitals, Banjara Hills, Hyderabad.