Duplex scanning, also called duplex ultrasound, is a technique that combines two ultrasound modes simultaneously: B-mode imaging, which provides a real-time picture of the vessel anatomy, and Doppler analysis, which measures blood flow velocity and direction. This combination allows sonographers to both see the physical structure of a blood vessel and assess how blood is flowing through it at the same time. Duplex scanning is the standard of care for evaluating the carotid arteries, peripheral veins for deep vein thrombosis, peripheral arteries for occlusive disease, and dialysis access grafts and fistulas. The term duplex reflects the dual nature of the examination.
Sonography Term