Study of B1 Mapping Methods Based on the Amplitude of MRI
Deng Guanhua1, Lan Maoying2, Duan Song2, Wang Jiajia2, Hu Can3, Xin Xuegang4#*
1Guangdong 999 Brain Hospital, Guangzhou 510510, China 2School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China 3Changhai Hospital Affiliated to the Second Military Medical University, Shanghai 200433, China 4South China University of Technology, Guangzhou 510006, China
Abstract：Recently developed technique of in vivo magnetic resonance electrical tomography (MR EPT) can extract the electrical properties of human tissues by using the information of B1field. Thus, robust B1 mapping technique, regarded as the base of the technique of MR EPT, is critical for MR EPT, because the quality of B1 maps directly affects the accuracy of MR EPT. In this paper, the B1 field scale factor (Ri) for double angle methods (DAM), saturated turbo flash (satTFL) in the scan of the phantom and human head were calculated using the FDTD simulation, and then the performance of DAM and satTFL was evaluated based on the mean relative difference(MRD). The results indicated that the difference of Ri between above methods was less than 10% in the tissue with low dielectric properties; on the contrary, the value of Ri of DAM was higher than that of satTFL, in the tissue with high dielectric properties such as cerebrospinal fluid, even up to 21% for DAM. The research of this study can be used to select the appropriate B1 mapping technique for different dielectric property tissues and promote the practical application of MR EPT technology.
邓官华, 蓝茂英, 段松, 王佳佳, 胡灿, 辛学刚. 基于磁共振信号幅值的射频场映像技术研究[J]. 中国生物医学工程学报, 2018, 37(2): 181-187.
Deng Guanhua, Lan Maoying, Duan Song, Wang Jiajia, Hu Can, Xin Xuegang. Study of B1 Mapping Methods Based on the Amplitude of MRI. Chinese Journal of Biomedical Engineering, 2018, 37(2): 181-187.
[1] Katscher U, Voigt T, Findeklee C, et al. Determination of electric conductivity and local SAR via B1 mapping [J]. IEEE Trans Med Imaging, 2009, 28(9): 1365-1374. [2] 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. [3] 辛学刚. 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. [4] Duan Song, Xu Chao, Deng Guanhua, et al. Quantitative analysis of the reconstruction errors of the currently popular algorithm of magnetic resonance electrical property tomography at the interfaces of adjacent tissues[J]. NMR Biomed, 2016, 29(6): 744-750. [5] Sha L, Ward ER, Stroy B, A review of dielectric properties of normal and malignant breast tissue [C].// Cleon Anderson W.Proceedings IEEE Southeast Conference 2002. New York: IEEE, 2002: 457-462. [6] Zywietz F, Knochel R. Dielectric properties of Co-γ-irradiated and microwave-heated rat tumour and skin measured in vivo between 0.2 and 2.4 GHz [J]. Phys Med Biol, 1986, 31(9):1021-1029. [7] Lu Y, Li B, Xu J, et al. Dielectric properties of human glioma and surrounding tissue [J]. Int J Hyperthermia, 1992, 8(6): 755-760. [8] Morimoto T, Kimura S, Konishi Y, et al. A study of the electrical bio-impedance of tumors [J].J Invest Surg, 1993, 6:25-32. [9] Li Zhou, Deng Guanhua, Li Zhe, et al. A large-scale measurement of dielectric properties of normal and malignant colorectal tissues obtained from cancer surgeries at Larmor frequencies [J]. Med Phys, 2016, 43(11):5991-5997. [10] Voigt T, Homann H, Katscher U, et al. Patient-individual local SAR determination: In vivo measurements and numerical validuation [J]. Magn Reson Med, 2012, 68(4):1117-1126. [11] Park DJ, Bangerter NK, Javed A, et al. A statistical analysis of the Bloch-Siegert B1 mapping technique [J]. Phys Med Biol, 2013, 58(16): 5673-5691. [12] Pohmann R, Scheffler K. A theoretical and experimental comparison of different techniques for B1 mapping at very high fields [J]. NMR Biomed, 2013, 26(3): 265-275. [13] Cunningham CH, Pauly JM, Nayak KS. Saturated double-angle method for rapid B1+ mapping [J]. Magn Reson Med, 2006, 55(6): 1326-1333. [14] Hartwig V, Vanello N, Giovannetti G, et al. B1+/actual flip angle and reception sensitivity mapping methods: Simulation and comparison [J]. Magn Reson Imaging, 2011, 29(5): 717-722. [15] Chung S, Kim D, Breton E, et al. Rapid B1+ mapping using a preconditioning RF pulse with Turbo FLASH readout [J]. Magn Reson Med, 2010, 64(2): 439-446. [16] Sacolick LI, Wiesinger F, Hancu I, et al. B1 mapping by Bloch-Siegert shift [J]. Magn Reson Med, 2010, 63(5): 1315-1322. [17] Hoult DI. The principle of reciprocity in signal strength calculations-a mathematical guide [J]. Concepts Magn Reson, 2000, 12(4): 173-187. [18] Wang Jinhua, Qiu Maolin, Yang QX, et al. Measurement and correction of transmitter and receiver induced nonuniformities in vivo [J]. Magn Reson Med, 2005, 53(2): 408-417. [19] DiIorio G, Brown JJ, Borrello JA, et al. Large angle spin-echo imaging [J]. Magn Reson Imaging, 1995, 13(1): 39-44. [20] Michel E, Hernandez D, Cho MH, et al. Denoising of B1+ field maps for noise-robust image reconstruction in electrical properties tomography [J]. Med Phys, 2014, 41(10):1023041-1023049. [21] Cloos MA, Bonmassar G. Towards direct B1 based local SAR estimation[C]//Proceedings of the 17th Annual Meeting of ISMRM. Concord: ISMRM, 2009: 3037-3037. [22] Ibrahim TS, Abduljalil AM, Baertlein BA, et al. Analysis of B1 field profiles and SAR values for multi-strut transverse electromagnetic RF coils in high field MRI applications [J]. Phys Med Biol, 2001, 46(10): 2545-2555. [23] Arteaga de Castro CS, Van Den Bergen B, Luijten PR, et al. Improving SNR and B1 transmit field for an endorectal coil in 7 T MRI and MRS of prostate cancer[J]. Magn Reson Med, 2012, 68(1): 311-318. [24] Ibrahim TS, Lee R, Baertlein BA, et al. B1 field homogeneity and SAR calculations for the birdcage coil [J]. Phys Med Biol, 2001, 46(2): 609-619. [25] Mao Weihua, Wang Zhangwei, Smith MB, et al. Calculation of SAR for transmit coil arrays [J].Concept Magn Reson B, 2007, 31(2): 127-131. [26] Christ A, Kainz W, Hahn EG, et al. The Virtual Family—development of surface-based anatomical models of two adults and two children for dosimetric simulations [J]. Phys Med Biol, 2009, 55(2): N23-N38. [27] Gabriel C. Compilation of the Dielectric Properties of Body Tissues at RF and Microwave Frequencies [R]. N.AL/OE-TR- 1996-0037, 1996. [28] 黄绮华, 高勇, 辛学刚. 高场和超高场 MR 下人体内B 1场均匀性及 SAR 随场强变化规律的研究[J]. 中国生物医学工程学报, 2013, 32(1): 21-27. [29] 黄绮华, 辜石勇, 辛学刚. 胎儿磁共振成像特定吸收率及B1场均匀性研究[J]. 微波学报, 2012 (S3): 416-419. [30] Fu Fanrui, Xin SX., Chen Wufan, Temperature-and frequency-dependent dielectric properties of biological tissues within the temperature and frequency ranges typically used for magnetic resonance imaging-guided focused ultrasound surgery[J]. Int J Hyperthermia, 2014, 30: 56-65. [31] Sharma A, Tadanki S, Jankiewicz M, et al. Highly-accelerated Bloch-Siegert |B1+| mapping using joint auto calibrated parallel image reconstruction [J]. Magn Reson Med, 2014, 71(4): 1470-1477. [32] Alecci M, Collins CM, Smith MB, et al. Radio frequency magnetic field mapping of a 3 Tesla birdcage coil: experimental and theoretical dependence on sample properties [J]. Magn Reson Med, 2001, 46(2): 379-385. [33] Barker GJ, Simmons A, Arridge SR, et al. A simple method for investigating the effects of non-uniformity of radiofrequency transmission and radiofrequency reception in MRI [J]. Brit J Radiol, 1998, 71(841): 59-67.
