基于分段式长码的超声粘弹性成像方法研究

项目名称： 基于分段式长码的超声粘弹性成像方法研究

项目编号： No.61201041

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 电子学与信息系统

项目作者： 刁现芬

作者单位： 深圳大学

项目金额： 22万元

中文摘要： 超声弹性成像技术对生物组织粘弹性的定量在临床诊断上具有重要意义,但在迈向临床实用化的过程中还面临诸多挑战。目前的超声弹性成像方法在检测分辨率、检测深度、与现有超声影像系统的集成、临床安全性等方面还存在问题亟待解决。本项目拟将分段式长码检测、自适应数字编码锁相技术、低频谐波激励引入到外加振子的超声弹性成像方法中。首先，利用分段式长码的编码增益和良好的相关特性，以期提高弹性成像系统的穿透力和空间分辨率；其次，采用基于自适应数字编码锁相技术的方法来提取剪切波相位，可以提高相位检测的精度；再次，采用低频谐波信号代替单一的正弦信号激励组织振动，实现不同频率的剪切波波速测量，从而实现粘性、弹性参数的测量。另外，我们还将根据回波信号对声场进行估计，采用自适应算法对回波信号进行补偿和校正，以减少组织的频率相关衰减、非线性效应对编码的影响。通过理论仿真分析、仿体、离体实验来检验该成像方法的关键性能指标。

中文关键词： 超声弹性成像；粘弹性；谐波激励；编码检测；

英文摘要： Tissue elasticity and viscosity are closely related to pathological changes. Quantitative measurement of tissue viscoelasticity has important medical applications. Ultrasound-based elastography, which has the advantages of real-time, noninvasive, low-cost, et al, has been investigated by a number of teams. However, the challenges are great before it gets widely clinical applications. Most of the ultrasound elasticity imaging techniques are limited by the resolution, penetration, clinical safety and integration with conventional imaging system, which require dedicated effort to strengthen the foundations of elastography. In this study, a new elastography imaging method is proposed, in which the truncated long code modulated pulse excitation takes the place of conventional pulse-echo ultrasound detection and the adaptive coded phase-locked loop technology is used to estimate the phase of the harmonic motion, the harmonically related low frequency sinusoidal vibration takes the place of single sinusoidal vibration to generate multiple frequencies shear waves. The idea of a truncated long code is that the coding time is extended to as long as the parameter estimation time window allows. The transmitted pulses are coded using different short codes from burst to burst and all the echoes are organized together coherent

英文关键词： ultrasonic elasticity imaging；viscoelasticity；harmonic vibration；code excitation；