离体甲状腺的高频超声成像和组织定征

本文用C扫高频超声显微镜对离体人体甲状腺的超声特性作了系统的研究。超声频段范围为25-55MHz。为定量对生物组织进行定征，本实验室建立一套高频超声显微镜系统，对政治客病变的离体人体甲状腺组织的三个典型的声参量进行了测量。测量结果表明：正常甲状腺的声速为1520m/s，在35MHz，超声衰减系数为3.4dB/mm，背向声散射系数为0.00157/(Srmm)，而病变甲状腺滤泡性腺瘤的速为1650m/s，超声衰减系数为6.6dB/mm，约为正常的2倍，背向声散射系数为0.00387/(Srmm)，比正常的大1倍半，除此之外，我们还得到正常和病变甲状腺的高频超声图象，并与组织的切片结果作了对比。

HIGH FREQUENCY ULTRASOUND IMAGE AND TISSUE CHARACTERIZATION FOR HUMAN THYROID

Ultrasonic properties of human thyroid were studied from frequency 25MHz to 55MHz with a C scan ultrasound backscatter microscope system. For quantitative evaluation of tissues, a C scan microscope system was set up. Three typical acoustic parameters of normal and diseased human thyroid were measured. The results showed that the speed of sound for normal thyroid was 1520m/s, while the sound speed was 1650m/s for the diseased thyroid. At frequency 35MHz, the attenuation coefficient of normal thyroid was 3.4dB/mm, and that of the diseased thyroid was 6.6dB/mm which was almost two times of that of normal thyroid. The backscatter coefficient of the diseased thyroid was 0.00387/(Srmm), which was two and a half times higher than that of normal thyroid (0.00157/(Srmm)). Besides, high resolution ultrasound images were produced with the C scan system, and the comparison of ultrasound images with histological slice diagrams showed identical results. The measured ultrasound properties were qualitatively related to their histological structure and imaging characterizations.