Medically reviewed by Nachiket J. Patel, MD, FACC, FSCAI. Last reviewed July 2026.
Vascular ultrasound uses sound waves to examine blood flow without radiation. It can evaluate leg arteries, deep and superficial veins, carotid arteries, and selected abdominal vessels.
The word ultrasound is broad. A DVT study, venous reflux study, arterial duplex, and carotid duplex are different examinations with different positions and measurements.
At Flow Heart & Vascular, the test is selected to answer the clinical question and the images are interpreted alongside symptoms, pulses, wounds, and prior procedures.
What types of vascular ultrasound are available?
- Lower-extremity arterial duplex for narrowed or blocked leg arteries
- Venous duplex for suspected DVT
- Venous reflux testing for chronic venous insufficiency and varicose veins
- Carotid duplex for plaque and narrowing in the neck arteries
- Surveillance of selected vascular stents or prior interventions
- Targeted studies based on a wound, swelling pattern, or vascular examination
What happens during the examination?
A technologist applies gel and moves a transducer over the area being studied. Doppler records blood-flow direction and velocity.
For a DVT study, the technologist gently compresses veins to see whether they close normally. For reflux testing, measurements may be taken while standing or with maneuvers that challenge the valves.
An arterial study may examine many segments from the groin to the ankle and may be paired with an ankle-brachial index (ABI), which compares ankle and arm pressures, or with toe-pressure measurements. A carotid study evaluates both sides of the neck.
How should I prepare?
Most leg and carotid studies require little preparation. Wear loose clothing and avoid applying heavy lotion over the area.
Some abdominal vascular studies require fasting because bowel gas can limit the view. Follow the instructions for the exact order rather than assuming all vascular ultrasounds are the same.
Continue medication unless specific instructions say otherwise. Bring information about prior stents, bypasses, clots, or vascular procedures.
What can arterial ultrasound show?
Arterial duplex can locate a velocity increase associated with narrowing, identify an occlusion, and assess flow beyond a diseased segment. The waveform also provides clues about upstream or downstream disease.
Results are interpreted with ankle or toe pressures, pulses, walking symptoms, rest pain, and wounds. An imaging abnormality alone does not determine whether a procedure is needed.
What can venous ultrasound show?
A DVT study can identify clot location and features suggesting whether it is acute or chronic. A reflux study measures failed valve closure in the superficial and deep systems.
Ultrasound may not fully visualize pelvic veins. Marked one-sided swelling or symptoms that do not fit the leg findings may lead to CT, MR, venography, or intravascular ultrasound.
How are results used?
Dr. Patel reviews the report and images, then explains which finding matches the patient’s symptoms. The next step may be reassurance, medical treatment, compression, walking therapy, another imaging test, or procedural planning.
Urgent findings are handled promptly. A scheduled ultrasound should never delay emergency care for a suddenly cold or weak limb, stroke symptoms, severe one-sided swelling with breathlessness, or another acute problem.
Frequently asked questions
Does vascular ultrasound hurt?
It is noninvasive. Pressure from the transducer or vein-compression maneuvers may be temporarily uncomfortable over a tender area.
Can ultrasound see every vascular blockage?
No. Body habitus, calcification, depth, wounds, bowel gas, and pelvic location can limit views. Another test may be needed.
Is a venous reflux study the same as a DVT ultrasound?
No. Both examine veins, but reflux testing uses a different protocol to assess valve function and often takes longer.
How is ultrasound different from CT or MRI?
Ultrasound shows blood flow in real time without radiation or injected contrast. CT and MRI can show anatomy that ultrasound cannot reach clearly, so the best test depends on the vessel and question.
Related heart and vascular information
- Peripheral Artery Disease (PAD)
- Deep Vein Thrombosis (DVT)
- Carotid Artery Disease (Blocked Neck Artery)
- Varicose Veins & Venous Insufficiency
Schedule an appointment
If you have a stable heart or circulation concern, request an appointment with Flow Heart & Vascular in Mesa, Arizona. Call 911 for emergency symptoms.
This page provides general education and does not replace individualized medical advice.
