Study On Ultrasonic Transmission Characteristics In Creature Multi-layered Tissue

For the last few years, ultrasound has been used widely in biology and medicine field. Ultrasonic characteristic is one of the elementary researches in biology medicine ultrasound. It is closely related with ultrasonic characteristic of creature organism. Ultrasonic scattering and absorption is a complicated processing. Biologic media is composed of water, fat and protein, which is different from even liquid matter. Because of uneven structure, its different part is scattered and absorbed. In view of ultrasonic diagnosis and treatment, it runs through skin and muscle, then tissue and organ. Ultrasonic parameters of creature structure differ in their kinds and directions. So someone purposed layered media structure to study transmission of biologic structure. Transmission law (interaction of organism and wave) and collecting way of diagnosis message is a physical foundation in ultrasonic diagnosis and treatment.Medical ultrasonics is a border discipline which combines acoustics and medical science together. Its main task is to study spread characteristics, laws and applications in the living beings organization of supersonic wave. I.e. the so-called ultrasonic tissue characterization is to study value range of various acoustic parameters and measurement methods in living beings organization, and corresponding relationships among these parameters and pathologic states and composition of tissues. We know supersonic wave carries a good deal of sound information characteristic of tissue structure after spreading in the biological tissue. We can find out the change laws of ultrasonic echo waves by learning the characteristics of the medium indirectly. Modern ultrasonic medical science is exactly based on spreading law of supersonic wave in the human body, to utilize the completely-developed signal processing method and electronic technology. Acoustic characteristic parameters of living beings organization are as follows, mainly Sound of spread speed, sound of reactance, attenuation coefficient, sound of scattering and some non-linear parameters. Because pathologic changes of some tissue can not be distinguished roughly from a certain acoustic parameter only, the quantitative research of the acoustic parameters of tissue is paid...