Development of Medical Ultrasound Imaging Techniques for Tissue Characterization (Attenuation Effect on Measurement and Tomography of Nonlinear Parameter)

조직 정량화를 위한 의용 초음파 영상 기술 개발(비선형 파라미터의 측정 및 단층영상에 미치는 감쇠의 영향)

In this paper attenuation effect on the measurement and the tomography of nonlinear parameter is discussed. We perform computer simulation with the method using harmonic components and the method using secondary wave components, and then estimate attenuation effect through the results and compare two measurement techniques. According to simulation result the attenuation effect is more intensive as large n and \ulcorner, and the degree of the attenuation effect is represented as error functions. In the aspect of measuremnet techniques, the method using secondary wave components is more insensitive to attenuation effect than the method using harmonic compnents. We obtain the same result in the nonlinear tomography, and show that the attenuation compensive filter is required because the whole tomogram is affected by frequency dependent attenuation(or nonlinear attenuation)