Studies of blood flow employing duplex, pulsed Doppler real-time sonography

The physics of pulsed Doppler techniques have been recently applied to clinical evaluation of superficial blood vessels and the flow within them. Essential physical principles of pulsed Doppler ultrasound are presented, including spectrum analysis and flow measurements. Duplex instrumentation combining high-resolution real-time imaging and a pulsed-Doppler system is described. Indications for duplex carotid sonography are outlined. Clinical applications are discussed and examples of normal and pathologic states are shown. Finally, the role of duplex sonography in the evaluation of carotid vascular disease is compared to traditional arteriographic and contemporary digital subtraction angiographic methods.