Duplex Ultrasound

         Basic Facts

  • Ultrasound is a painless, noninvasive, radiation-free diagnostic test that uses high-frequency sound waves to make images of body tissues. 
  • Duplex ultrasound allows doctors to measure the speed of blood flow and to see images of the blood vessels.
  • Physicians use duplex ultrasound to diagnose and examine diseases that affect the blood vessels, as well as to plan for surgical and minimally invasive therapies.

Duplex ultrasound uses high-frequency sound waves to produce images that differentiate between the body's soft tissues and its fluid-filled structures. Duplex ultrasound can also detect motion, such as the movement of blood cells.

A physician can use ultrasound to evaluate the veins and arteries in a person's neck, arms, abdomen, and legs. The test also allows the physician to watch blood as it flows through blood vessels.

Duplex UltrasoundUltrasound uses sound waves higher than human hearing can detect. A device called a transducer that connects to a computer and control panel emits ultrasound waves are directed through the skin and into the body. When the sound waves hit body structures, such as blood vessels, they echo off of the structures and then travel back toward the transducer. A computer analyzes the echoes, the time it takes them to travel, and their distance from the transducer and produces a two-dimensional, real-time image of the shape and structure of blood vessels.

Duplex ultrasound combines standard ultrasound technology and Doppler ultrasound, which uses short-bursts of ultrasonic waves to produce images of the direction and speed of the flow of blood. Duplex ultrasound allows physicians to measure the velocity of blood flow and to see images of the structure of the blood vessel through which the blood is flowing.

Duplex Ultrasound FAQ