2ND-HARMONIC CHARACTERISTICS OF THE ULTRASOUND CONTRAST AGENTS ALBUNEX AND FSO69

Techniques necessary for measurement of the second harmonic of the ins onifying frequency backscattered from ultrasonic contrast agents are d escribed, and used to determine this characteristic for the agents Alb unex(R) and FS069. The results confirm theoretical predictions that sc attered second harmonic pressure is proportional to the square of the incident pressure. Because contrast agents of the type investigated im prove discrimination of blood echoes against tissue echoes by means of the second harmonic of the insonifying frequency, these results allow a comparison of the relative merits of Albunex and FS069 for harmonic imaging. (C) 1997 World Federation for Ultrasound in Medicine & Biolo gy.