ABSTRACT
The basis of ultrasound as an imaging technique is the interaction between transmitted sound waves and the juxtaposed different acoustic impedances of body tissues. Ultrasound probes emit pulsed sound waves of a specific frequency, usually between 1 and 30 MHz-the normal human hearing frequency range is up to 20 KHz-and a defined depth of penetration. As the sound waves penetrate through tissues of various impedances, some are reflected back towards the transducers on the probe. By calculating the time difference between transmission and reception, an image is generated through the processing of a multitude of sound waves (1,2).
