Ultrasonic backscatter from mammalian tissues.

Ultrasonic B-mode images are formed from echoes backscattered from tissue structures in the body. Quantitative analysis of this signal from tissues may provide additional information about the tissues which may be valuable for clinical diagnosis. Results on measurements of backscatter properties of tissues such as heart, liver, and blood have been reported by a number of investigators. Data on other tissues such as spleen, kidney, and pancreas, however, are still very scanty. In this paper, results on ultrasonic backscattering properties of bovine heart, liver, kidney, spleen, pancreas, and rat myocardium, recently obtained in our laboratory utilizing a computerized system over the frequency range of 2-7 MHz, are presented. The results show that for all the tissues investigated, backscatter from liver is the highest, while that from spleen is the lowest. Liver and pancreas exhibit frequency dependence distinctively different from other tissues. Moreover, backscatter from bovine myocardium is found to be higher than that from rat myocardium. The significance of these findings in relation to the histological composition of these tissues is discussed.