Types of Ultrasound: Doppler vs. Duplex

March 15 2021

Duplex ultrasonography machine screen with color images on it

When comparing Doppler vs. duplex, it’s important to note that they are closely related. In fact, duplex ultrasound is a type of Doppler ultrasonography. Duplex ultrasound combines both traditional and Doppler procedures. The result is live, high-definition pictures of blood flow.

There are many different types of duplex ultrasound, including carotid, renal, arterial, and venous ultrasound. Healthcare professionals use each type to analyze different areas of the body.

On the other hand, Doppler ultrasound utilizes the Doppler principle to measure the velocity and direction of blood flow. There are also a variety of Doppler ultrasound types.

Learn more about the differences between Doppler vs. duplex. Get a better understanding of the types of ultrasound out there, and find the best fit for your healthcare practice.

Doppler vs. Duplex: The Differences

Doppler and duplex technology work in the same way. They are both types of ultrasound, meaning they are both non-invasive studies that use high-frequency sound waves.

The differences are found in the images and information collected by each. In regards to images, a Doppler scan produces a color image of blood flow. Duplex ultrasonography provides this same image, plus a two-dimensional greyscale image of surrounding tissues.

The information from each scan also varies. Doppler ultrasonography gives the user information about the direction, speed, and turbulence of blood flow. Duplex ultrasonography takes it a step further by providing additional information about the surrounding tissues.

Learn more about both Doppler and duplex ultrasound below.

Doppler Ultrasound

Doppler ultrasound utilizes the Doppler effect. The Doppler effect refers to the concept that sound wave frequency changes as an object moves.

For example, when an ambulance is approaching, the frequency of sound waves in front of the vehicle will increase as it gets closer and decrease as it passes. This makes the pitch higher as it approaches and lower as it drives away.

Using this concept in ultrasonography allows healthcare professionals to collect information on blood flow. The Doppler transducer emits high-frequency sound waves that bounce off of circulating red blood cells, creating pulses. A computer then captures these pulses and converts them into images.

Doppler ultrasound helps users find the velocity of blood flow, which indicates whether or not a patient’s arterial blood vessels are diseased. A Doppler scan can also be used during pregnancy to evaluate the blood flow of the fetus.

These are just two of the many different applications for this type of ultrasound. Learn more about Doppler ultrasound here.

Duplex Ultrasound

The term “duplex” implies the use of two ultrasound modes. Duplex ultrasound utilizes both Doppler and B-mode ultrasound. The B-mode transducer collects an image of the vessel under examination, while the Doppler probe inside the transducer evaluates the velocity and direction of blood flow.

There are a variety of duplex ultrasonography types, each of which has different applications. For instance, a carotid duplex may be used to check for occlusion or stenosis of arteries of the neck or branches of the carotid artery.

Arterial or venous duplex scans are used to examine vessels and blood flow in the abdomen. Renal duplex ultrasound is used to assess the kidneys. With many different types of ultrasound available, there is a fit for every practice.

Doppler scan images on a computer screen

Purchasing High-Quality, Affordable Ultrasound Equipment

There are many different types of ultrasound equipment. Choosing an ultrasound machine for your practice will depend on your applications, patients, and needs.

Not sure which ultrasound equipment is right for your facility? UltrasoundQuotes can help. We host the largest inventory of new and used ultrasound machines for sale online. This includes both Doppler and duplex ultrasonography options, and more! Plus, we provide free, transparent information and pricing on each listing.

Now, you can compare ultrasound machines in one place. Browse options from industry-leading manufacturers from the comfort of your home. Find the best deal on high-quality ultrasound equipment today.

Get Pricing on a Variety of Ultrasound Machines for Sale Today.