人体组织电特性磁共振断层成像（MR EPT）技术进展

doi:10.3969/j.issn.0258-8021.2015.01.012

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摘要科学研究早已证实，人体组织的电特性参数（包括电导率和电容率）在正常组织与肿瘤组织之间差异较大，因此测量人体活体组织的电特性参数变化有可能成为肿瘤早期诊断的有效手段。磁共振成像（MRI）本质上是非电离电磁场，即强的静磁场、梯度磁场和射频电磁场与人体组织的相互作用，因此MRI影像信息中必然包含人体组织的电特性信息。MRI领域近年来新兴的研究热点之一人体组织电特性磁共振断层成像（MR EPT）技术，其就是研究如何从MRI影像信息中有效提取人体组织电特性信息。本文概述MR EPT技术的产生背景，从反映电磁场基本运动规律的麦克斯韦方程组出发，解析给出MR射频场与人体组织电特性参数之间的量化关系，深入剖析了3 T和7 T不同场强下MR EPT成像方法的国际研究进展以及潜在的技术突破口。同时，还介绍目前运用MR EPT技术开展的动物实验和前期临床人体测试等情况，展示这一新兴技术的诱人前景。

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	辛学刚¹
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关键词 ：生物组织电特性, 人体组织电特性磁共振断层成像, 磁共振射频, 癌症早期检测

Abstract：It has been demonstrated that electrical properties, such as the conductivity and permitivity, are usually very different between healthy and tumor tissues. Therefore, the in vivo measurement of electrical properties may be a potential method for the early detection of cancers. In principle, the magnetic resonance imaging (MRI) system is the interaction between the nonionized electromagnetic field, including strong static magnetic field, gradient magnetic field, and radiofrequency field, and the human tissues, thus the information of electrical properties is definitely embedded inside the MRI. Recently developed
technigue of in vivo magnetic resonance electrical property tomography (MR EPT) of human tissues are exactly the
technigue for the in vivo extraction of electrical properties from tissues. This paper introduces the background of MR EPT, analytically deduces the quantitatively relationship between the MRI radiofrequency field and the electrical properties of tissues based on the Maxwell’s equations, which are the governing equations for the description of the behaviors of electromagnetic fields inside tissues. The efficacy, deficiency and potentials of the MR EPT technique at 3 T and 7 T are respectively analyzed according to the international updated progress. The preliminary clinical research of in vivo measurement of electrical properties of healthy and tumor tissues using MR EPT technique is summarized, showing the promising future of this cuttingedge technique.

Key words： electrical properties of biological tissues magnetic resonance electrical properties tomography (MR EPT) of human tissues magnetic resonance radiofrequency(MR RF) early detection of cancer

基金资助:国家自然科学基金重点项目（69735101）；广州市科技计划项目（2014J4100160）

引用本文:

辛学刚^1,2*. 人体组织电特性磁共振断层成像（MR EPT）技术进展[J]. 中国生物医学工程学报, 2015, 34(1): 83-90.
Xin Xuegang^1,2#*. Technological Progresses of the Magnetic Resonance Electrical Property Tomography of Human Tissues. journal1, 2015, 34(1): 83-90.

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http://cjbme.csbme.org/CN/10.3969/j.issn.0258-8021.2015.01.012 或 http://cjbme.csbme.org/CN/Y2015/V34/I1/83

［1］Gabriel C, Gabriel S, Corthout E. The dielectric properties of biological tissues: I. Literature survey ［J］. Phys Med Biol, 1996, 〖STHZ〗41〖STBZ〗(11): 2231-2249.
［2］Gabriel S, Lau RW, Gabriel C. The dielectric properties of biological tissues: II. Measurements in the frequency range 10 Hz to 20 GHz ［J］. Phys Med Biol, 1996, 41(11): 2251-2269.
［3］Gabriel S, Lau RW, Gabriel C. The dielectric properties of biological tissues: III. Parametric models for the dielectric spectrum of tissues ［J］. Phys Med Biol, 1996, 41(11): 2271-2293.
［4］Joines WT, Zhang Yang, Li Chenxing, et al. The measured electrical properties of normal and malignant human tissues from 50 to 900 MHz ［J］. Med Phys, 1994, 21(4): 547-550.
［5］Lu Yongjun, Li Baomin, Xu Jianping, et al. Dielectric properties of human glioma and surrounding tissue ［J］. Int J Hyperthermia, 1992, 8(6): 755-760.
［6］Surowiec AJ, Stuchly SS, Barr JB, et al. Dielectric properties of breast carcinoma and the surrounding tissues ［J］. IEEE Trans Biomed Eng, 1988, 35(4): 257-263.
［7］Fear EC, Xu Li, Susan CH, et al. Confocal microwave imaging for breast cancer detection: localization of tumors in three dimensions ［J］. IEEE Trans Biomed Eng, 2002, 49(8): 812-822.
［8］Haemmerich D, Staelin ST, Tsai JZ, et al. In vivo electrical conductivity of hepatic tumours ［J］. Physiol Meas, 2003, 24(2): 251-260.
［9］Smallwood RH, Keshtkar A, Wilkinson BA, et al. Electrical impedance spectroscopy (EIS) in the urinary bladder: the effect of inflammation and edema on identification of malignancy ［J］. IEEE Trans Med Imaging, 2002, 21(6): 708-710.
［10］Stuchly MA, Stuchly SS. Coaxial line reflection methods for measuring dielectric properties of biological substances at radio and microwave frequenciesa review ［J］. IEEE Transactions on Instrumentation and Measurement, 1980, 29(3): 176-183.
［11］Venkatesh M, Raghavan G. An overview of dielectric properties measuring techniques ［J］. Canadian Biosystems Engineering, 2005, 47(7): 15-30.
［12］Henderson RP, Webster JG. An impedance camera for spatially specific measurements of the thorax ［J］. IEEE Transactions on Biomedical Engineering, 1978, 25(3): 250-254.
［13］Barber DC, Brown BH. Applied Potential Tomography ［J］. Journal of physics E Scientific instruments, 1984, 17(9): 723-733.
［14］董秀珍. 生物电阻抗成像研究的现状与挑战 ［J］. 中国生物医学工程学报, 2008, 27(5): 641-649.
［15］Liston AD, Bayford RH, Tidswell AT, et al. A multishell algorithm to reconstruct EIT images of brain function ［J］. Physiol Meas, 2002, 23(1): 105-119.
［16］Woo EJ, Lee SY, Mun CW. Impedance tomography using internal current density distribution measured by nuclear magnetic resonance ［C］ //Bookstein FL, Duncan JS, Lange N, Wilson DC, eds. Mathematical Methods in Medical Imaging III. San Diego, CA: SPIE, 1994: 377-385.
［17］Joy ML, Scott GC, Henkelman RM. In vivi detection of applied electric currents by magnetic resonance imaging ［J］. Magnetic Resonance Imaging, 1989, 7(1): 89-94.
［18］Li Xu, He Bin. Multiexcitation magnetoacoustic tomography with magnetic induction for bioimpedance imaging ［J］. IEEE Trans Med Imaging, 2010, 29(10): 1759-1767.
［19］Haacke EM, Petropoulos LS, Nilges EW, et al. Extraction of conductivity and permittivity using magnetic resonance imaging ［J］. Phys Med Biol, 1991, 36(6): 723-734.
［20］Wen Han. Noninvasive quantitative mapping of conductivity and dielectric distributions using RF wave propagation effects in highfield MRI ［C］ //Yaffe MJ, Antonuk LE, eds. Physics of Medical Imaging. San Diego, CA: SPIE, 2003: 471-477.
［21］Katscher U, Voigt T, Findeklee C, et al. Determination of Electric Conductivity and Local SAR Via B1 Mapping ［J］. Medical Imaging, IEEE Transactions on, 2009, 28(9): 1365-1374.
［22］Sled JG, Pike GB. Standingwave and RF penetration artifacts caused by elliptic geometry: an electrodynamic analysis of MRI ［J］. IEEE Transactions on Medical Imaging, 1998, 17(4): 653-662.
［23］Zhang Xiaotong, Zhu Shanan, He Bin. Imaging Electric Properties of Biological Tissues by RF Field Mapping in MRI ［J］. IEEE Transactions on Medical Imaging, 2010, 29(2): 474-481.
［24］Stehning C, Voigt TR, Katscher U. Realtime conductivity mapping using balanced SSFP and phasebased reconstruction ［C］ //Proceedings of the 19th Annual Meeting of the International Society for Magnetic Resonance in Medicine. Montréal: ISMRM, 2011: 128. 
［25］Voigt T, Katscher U, Doessel O. Quantitative conductivity and permittivity imaging of the human brain using electric properties tomography ［J］. Magnetic Resonance in Medicine, 2011, 66(2): 456-466.
［26］Seo JK, Kim MO, Lee J, et al. Error Analysis of Nonconstant Admittivity for MRBased Electric Property Imaging ［J］. IEEE Transactions on Medical Imaging, 2012, 31(2): 430-437.
［27］Seo JK, Kim DH, Lee J, et al. Electrical tissue property imaging using MRI at dc and Larmor frequency ［J］. Inverse Problems, 2012, 28(8): 1-26.
［28］Sodickson DK, Alon Leeor, Deniz CM, et al. Local Maxwell tomography using transmitreceive coil arrays for contactfree mapping of tissue electrical properties and determination of absolute RF phase［C］//Proceedings of the 20th Annual Meeting of the International Society for Magnetic Resonance in Medicine. Melbourne: ISMRM, 2012: 387. 
［29］Van Lier AL, Brunner DO, Pruessmann KP, et al. B1(+) phase mapping at 7 T and its application for in vivo electrical conductivity mapping ［J］. Magn Reson Med, 2012, 〖STHZ〗67〖STBZ〗(2): 552-561.
［30］Liu Jiaen, Zhang Xiaotong, Van de Moortele PF, et al. Determining electrical properties based on B1 fields measured in an MR scanner using a multichannel transmit/receive coil: a general approach ［J］. Phys Med Biol, 2013, 58(13): 4395-4408.
［31］Zhang Xiaotong, Van de Moortele PF, Schmitter S, et al. Complex B1 mapping and electrical properties imaging of the human brain using a 16-channel transceiver coil at 7T ［J］. Magnetic Resonance in Medicine, 2013, 69(5): 1285-1296.
［32］Ibrahim TS, Mitchell C, Abraham R, et al. Indepth study of the electromagnetics of ultrahighfield MRI ［J］. NMR Biomed, 2007, 20(1): 58-68.［33］Collins CM, Wang Zhangwei. Calculation of radiofrequency electromagnetic fields and their effects in MRI of human subjects ［J］. Magnetic Resonance in Medicine, 2011, 65(5): 1470-1482.
［34］Bulumulla SB, Lee SK, Yeo DTB. Conductivity and permittivity imaging at 30 t ［J］. Concepts in Magnetic Resonance Part B: Magnetic Resonance Engineering, 2012, 41B(1): 13-21.
［35］Hoult DI. The principle of reciprocity in signal strength calculations—A mathematical guide ［J］. Concepts in Magnetic Resonance, 2000, 124): 173-187.
［36］Voigt T, Homann H, Katscher U, et al. Patientindividual local SAR determination: In vivo measurements and numerical validation ［J］. Magnetic Resonance in Medicine, 2012, 68(4): 1117-1126.
［37］Yarnykh VL. Actual flipangle imaging in the pulsed steady state: a method for rapid threedimensional mapping of the transmitted radiofrequency field ［J］. Magn Reson Med, 2007, 57(1): 192-200.
［38］Van de Moortele PF, Snyder C, DelaBarre L, et al. Calibration tools for RF shim at very high field with multiple element RF coils: from ultra fast local relative phase to absolute magnitude B1+mapping［C］//Proceedings of the 15th Annual Meeting of the International Society for Magnetic Resonance in Medicine. Berlin: ISMRM, 2007: 1676. 
［39］Adriany G, Van de Moortele PF, Ritter J, et al. A geometrically adjustable 16-channel transmit/receive transmission line array for improved RF efficiency and parallel imaging performance at 7 Tesla ［J］. Magn Reson Med, 2008, 59(3): 590-597.
［40］Van Lier AL, Hoogduin JM, Polders DL, et al. Electrical conductivity imaging of brain tumours ［C］//
Proceedings of the 19th Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Montréal: ISMRM, 2011: 4464. 
［41］Katscher U, Djamshidi K, Voigt T, et al. Estimation of breast tumor conductivity using parabolic phase fitting ［C］//Proceedings of the 20th Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Melbourne: ISMRM, 2012: 3482.
［42］Bulumulla SB, Hancu I. Breast Permittivity Imaging ［C］ //Proceedings of the 20th Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Melbourne: ISMRM, 2012: 2532. 
［43］Voigt T, Schuster A, Ishida M, et al. Conductivity imaging of an ischemic pig heart model using electric properties tomography ［C］//Proceedings of the 20th Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Melbourne, Australia: ISMRM, 2012: 3483.
［44］Van Lier A, Van der Kolk AG, Brundel M, et al. Electrical conductivity in ischemic stroke at 70 Tesla: A Case Study ［C］ //Proceedings of the 20th Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Melbourne: ISMRM, 2012: 3484. 
［45］Stehning C, Voigt T, Karkowski P, et al. Electric Properties Tomography (EPT) of the Liver in a Single Breathhold Using SSFP［C］//Proceedings of the 20th Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Melbourne, Australia: ISMRM, 2012: 386. 
［46］Balidemaj E, Van Lier AL, Nederveen AJ, et al. Feasibility of EPT in the Human Pelvis at 3T［C］//
Proceedings of the 20th Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Melbourne: ISMRM, 2012: 3468. 
［47］Balidemaj E, Van Lier AL, Crezee J, et al. Determining the patientspecific conductivity of pelvic tumors for use in Hyperthermia Treatment Planning［C］Proceedings of the 21st Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Salt Lake City: ISMRM, 2013: 4178.
［48］Shin J, Kim MJ, Lee J, et al. Coil combine for conductivity mapping of breast cancer［C］//Proceedings of the 21st Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Salt Lake City: ISMRM, 2013: 4180. 
［49］Oh TI, Jeong WC, McEwan A, et al. Feasibility of magnetic resonance electrical impedance tomography (MREIT) conductivity imaging to evaluate brain abscess lesion: In vivo canine model ［J］. Journal of Magnetic Resonance Imaging, 2013, 38(1): 189-197.
［50］Kim MO, Choi N, Shin J, et al. Phase unbanding in bSSFP for liver conductivity imaging at 30T ［C］ // Editorial board, eds. Proceedings of the 21st Scientific Meeting of the International Society for Magnetic Resonance in Medicine. Salt Lake City: ISMRM, 2013: 4173.
［51］Bottomley PA, Hardy CJ, Argersinger RE, et al. A Review of1H Nuclear Magnetic Resonance Relaxation in Pathology: Are T1 and T2 diagnostic? ［J］. Medical Physics, 1987, 14(1): 1-37.