摘要
磁声耦合成像技术利用电磁声三物理场耦合作用的原理,通过声检测方式重建电导率存在明显变化的组织轮廓,实现恶性肿瘤的早期检测。本文建立双层同心球模型,模拟被正常组织包裹的病变组织,利用声场中的时间反转法以及电磁场方程,求解组织中的电导率分布,研究了由检测声压计算电导率分布的重建算法,并进行了仿真分析。仿真结果显示重建的电导率分布图像在电导率边界处清晰可见,进而验证了应用磁声耦合成像对电导率边界进行功能成像的可行性,为恶性肿瘤的早期检测提供了一种新的功能成像方法。
The electric characteristics such as impedance and conductivity of the organization will change in the case where pathological changes occurred in the biological tissue.The change in electric characteristics usually took place before the change in the density of tissues,and also,the difference in electric characteristics such as conductivity between normal tissue and pathological tissue is obvious.The method of magneto-acoustic tomography with magnetic induction is based on the theory of magnetic eddy current induction,the principle of vibration generation and acoustic transmission to get the boundary of the pathological tissue.The pathological change could be inspected by electricity characteristic imaging which is invasive to the tissue.In this study,a two-layer concentric spherical model is established to simulate the malignant tumor tissue surrounded by normal tissue;mutual relations of the magneto-sound coupling effect and the coupling equations in the magnetic field are used to get the algorithms for reconstructing the conductivity.Simulation study is conducted to test the proposed model and validate the performance of the reconstructed algorithms.The result indicates that the use of signal processing method in this paper can image the conductivity boundaries of the sample in the scanning cross section.The computer simulating results validate the feasibility of applying the method of magneto-acoustic tomography with magnetic induction for malignant tumor imaging.
出处
《生物医学工程学杂志》
EI
CAS
CSCD
北大核心
2010年第2期416-420,共5页
Journal of Biomedical Engineering
基金
国家自然科学基金资助项目(30770557)
天津市应用基础重点项目资助(07JCZDJC07000)
科技部科研院所技术开发研究专项项目资助(NCSTE-2007-JKZX-307)
关键词
磁声耦合效应
洛合兹力
电导率
图像重建
Magneto-acoustic coupling effect
Lorentz force
Conductivity
Image reconstruction
