Doppler Ultrasound of the Leg

A Doppler ultrasound is a special type of ultrasound which shows blood flow as colour images based on the speed and direction of flow.

A Doppler ultrasound (Doppler test) is typically used to scan the legs to examine arterial blood flow (circulation) and detect clots.

How is a Doppler ultrasound performed?

A Doppler ultrasound uses a special probe that us applied with mild to moderate pressure against the leg, over the areas where veins are found. A gel is used on the skin to form an acoustic interface with the probe. Pressure may be uncomfortable over tender areas.

The examination usually takes about half an hour, but may take more than an hour if arterial flow is being assessed.

When would you need a Doppler ultrasound?

A Doppler ultrasound of the legs may be requested when a deep vein thrombosis (DVT, a clot in the deep veins of the leg) is suspected.

Symptoms of a DVT include calf or leg pain and swelling of the calf or ankle.

A Doppler ultrasound is also capable of assessing arterial blood flow in the lower limbs, to look for areas of narrowing due to atherosclerosis or to assess the function of arterial grafts, in people with peripheral vascular disease (PVD).

Test results explained

Doppler ultrasounds shows blood flow as blue or red spreading areas (colour flow). These images are stored electronically and can be printed out for viewing, but most of the information is gained by an experienced sonographer during the actual examination.

A clot in a vein will prevent flow being seen in that vessel, and will make the vein solid, being non-compressible with the ultrasound transducer.

Superficial veins are differentiated from deep veins. Clots in superficial veins is usually not serious, but may progress to clotting in the deeper veins.

Arterial assessment aims to determine the presence of narrowed blood vessels and does this by evaluating the speed and quality of flow within these vessels. The report will usually describe the severity of the stenosis (narrowing).

Related specialists

• General Practitioner (GP)
• Radiologist
• Vascular Surgeon
• General Physician
• Diabetologist
• Medical Oncologist
• Respiratory Physician
• Orthopaedic Surgeon

Related tests

• D-Dimer
• Carotid Doppler Ultrasound Scan
• CT Pulmonary Angiogram (CTPA)
• VQ Scan (Ventilation-Perfusion Scan)
• Echocardiogram (Echo)
• Electrocardiogram (ECG)
• INR Test (International Normalised Ratio)

Also known as

• Lower extremity Doppler
• Doppler test
• Sonography
• Sonogram
• Sonar
• US
• U/S
• USS

Links

• Wikipedia – Doppler ultrasound

This article is for informational purposes only and should not be taken as medical advice. If in doubt, HealthEngine recommends consulting with a registered health practitioner.