Abstract
Real-time ultrasound imaging techniques have almost totally replaced static B-mode gray scale imaging. The increased use of real-time imaging is the result of advances in transducer technology, the miniaturization of electronics through the development of digital circuitry, advances in computer software, and improved ultrasonic focusing. The final result has been an increase in image quality and information content for real-time ultrasound. A review of basic real-time ultrasound instrumentation is presented. Sector scanners, linear arrays, and phased arrays are discussed in detail. Electronic focusing methods (transmit and receive focusing) are explained with many illustrative examples. The new imaging technique of endosonography or transonography is introduced.