软组织超声频谱实验和分析

EXPERIMENTS AND ANALYSES OF ULTRASOUNDSPECTRA OF SOFT TISSUES

本文介绍了用窄带和宽带超声换能器对脂肪、肌肉、肌纤维瘤等软组织进行声衰减和散射的频谱实验和分析,并结合组织的生理结构进行了讨论。实验结果表明:(1)肌纤维组织的声衰减有明显的方向性,而肌纤维瘤则失去了这一特征,且声衰减增大。(2)频率在3MHz以下,背向散射很弱,超过3MHz后,散射的强度随频率的升高而近似成指数趋势上升。(3)接收换能器的带宽对声谱分布特征有很大影响。

<ABSTRACT> In this paper, experiments on attenuation and scatter of ultrasound spectra of soft tissues were made and resu1ts discussed combined together with physiological structure characteristics of the tissues. Two kinds of transducers (narrow-band and wide-band ) were used in the experiments. The results showed that the spectra of muscle fiber tissue had obvious directional feature of attenuation, but the spectra of myofibroma tumor tissue lost this feature and attenuated greatly. The intensity of scatter was weak when the frequency was below 3 MHz, and increased exponentially with the frequency when the latter is above 3 MHz. Besides, the bandwi- dth of the receiving transducer exerted great effect on the character istics of spectrum distribution.