本研究中，我們結合了預先極化技術以及超導量子干涉元件(Superconducting quantum interference device, SQUID)，開發低磁場核磁共振及核磁造影系統。此系統由主要由均勻磁場、預極化磁場、SQUID及3維造影梯度磁場所組成。為了降低環境雜訊的影響， 我們將系統置於屏蔽箱中，進而提高系統的靈敏度。在NMR量測中，經由梯度磁場補償提高系統磁場的均勻度後，10 ml水樣品的磁共振頻譜線寬可小於1 Hz，且訊雜比可達110；在磁振造影量測中我們對不同大小的水樣品進行造影，驗證本系統空間解析度可達2 mm，此系統將來可應用於生物活體使用，且系統體積小造價低，具有產業化的潛力。

關鍵字：低場核磁共振、磁振造影、預先極化、超導量子干涉元件

[1] S. Appelt, A. Ben-Amar Baranga, C.J. Erickson, M.V. Romalis, A.R.Young, W. Happer “Theory of spin-exchange optical pumping of 3He and 129Xe”, Phys. Rev. A 58, 1412 (1998).
[2] Shu-Hsien Liao, Kai-Wen Huang, Hong-Chang Yang*, Chang-Te Yen, M. J. Chen, Hsin-Hsien Chen, Herng-Er Horng*, and Shieh Yueh Yang, “Characterization of tumors using SQUID-detected nuclear magnetic resonance and imaging”,Appl. Phys. Lett. 97, 263701 (2010)
[3] M. Goldman, H. Jo’hannesson, O. Axelsson, M. Karlsson, “Hyperpolarization of 13C through order transfer from parahydrogen: A new contrast agent for MRI ”,Magn.Reson. Imaging 23, 153 (2005)
[4] G. Navon, Y.-Q. Song, T. Ro˜o˜m, S. Appelt, R.E. Taylor, A. Pines,” Enhancement of Solution NMR and MRI with Laser-Polarized Xenon”, Science 271, 1848 (1996).
[5] S. Appelt, F.W. Ha‥sing, S. Baer-Lang, N.J. Shah, B. Blümich, “Enhancement of Solution NMR and MRI with Laser-Polarized Xenon”, Chem. Phys. Lett. 348, 263 (2001)
[6] Shu-Hsien Liao and Herng-Er Horng, Hong-Chang Yang, and Shieh-Yueh Yang, “Longitudinal relaxation time detection using a high-Tc superconductive quantum interference device magnetmeter”,J. Appl. Phys. 102, 033914 (2007).
[7] M.A. Espy, A.N. Matlachov, P.L. Volegov, J.C. Mosher, and R.H.Kraus Jr., ” SQUID-Based Simultaneous Detection of NMR and Biomagnetic Signals at Ultra-Low Magnetic Fields”, IEEE Trans.Appl. Supercon. 15, 635 (2005).
[8] A.H. Trabesinger, R. McDermott, S.K. Lee, M. Mu1ck, J. Clarke, and A. Pines, “ SQUID-Detected Liquid State NMR in Microtesla Fields“, J. Phys. Chem. A 108, 957-963 (2004).
[9] R. McDermott, S.K. Lee, B. ten Haken, A.H. Trabesinger, A. Pines, and J. Clarke, “Microtesla MRI with a superconducting quantum interference Device”, Proc. Natl. Acad. Sci. USA 101, 7857 (2004).
[10] M. Mössle, S. Busch, M. Hatridge, W. Myers, A. Pines, and J. Clarke, “SQUID-detected microtesla MRI: a new modality for tumor detection”, paper presented at 2006 Applied Superconductivity conference, Aug. 27-Sept.1, 2006, Seattle, Washington, USA.
[11] Y. S. Greenberg, “Application of superconducting quantum interference devices to nuclear magnetic resonance,” Rev. Mod. Phys., vol. 70, 175(2002.)
[12] R. McDermott, A. H. Trabesinger, M. Mück, E. L. Haln, A. Pines, and J. Clarke, “Liquid-state NMR and scalar couplings in microtesla magnetic fields,” Science, vol. 295, 2247( 2002.)
[13] Y. Zhang, L. Qiu, H. Krause, S. Hartiwig, M. Burghoff, and L. Trahms,“Liquid state nuclear magnetic resonance at low fields using a nitrogencooled superconducting quantum interference device,” Appl. Phys. Lett.,vol. 90,182503(2007)
[14] K. Schlenga, R. McDermott, J. Clarke, R. E. de Souza, A. Wong-Foy, and A. Pines, “Low-field magnetic resonance imaging with a high- Tc dc superconducting quantum interference device,” Appl. Phys. Lett., vol. 75,3695(1999)
[15] H. C. Yang, S. H. Liao, H. E. Horng, S. L. Kuo, H. H. Chen, and S. Y. Yang, “Enhancement of nuclear magnetic resonance in microtesla magnetic field with prepolarization field detected with high-Tc superconducting quantum interference device,” Appl. Phys. Lett., vol. 88,252505( 2006.)
[16] M. Burghoff, S. Hartwig, L. Trahms, and J. Bernarding, “Nuclear magnetic resonance in the nanoTesla range,” App. Phys. Lett., vol. 87, 054103(2005.)
[17] L. Qiu, Y. Zhang, H. J. Krause, A. H. Braginski, M. Burghoff, and L. Trahms, “Nuclear magnetic resonance in the earth’s magnetic field using a nitrogen-cooled superconducting quantum interference device,”Appl. Phys. Lett., vol. 91, 072505(2007.)
[18] S. H. Liao, H. E. Horng, H. C. Yang, and S. Y. Yang, “Longitudinal relaxation time detection using a high-Tc superconductive quantum interference device magnetometer,” J. Appl. Phys., vol. 102, 033914(2007.)
[19] J. Clarke, M. Hatridge, and M. Mößle, “Resonance imaging in Microtesla,” Annu. Biomed. Eng., vol. 9,389( 2007.)
[20] S. H. Liao, H. C. Yang, H. E. Horng, S. Y. Yang, H. H. Chen,D. W. Hwang, and L. P. Hwang, “Sensitive J-coupling spectroscopy using high-Tc superconducting quantum interference devices in magnetic fields as low as microteslas,” Supercond. Sci. Technol., vol. 22,045008(2009)
[21] S. H. Liao, H. C. Yang, H. E. Horng, and S. Y. Yang, “Characterization of magnetic nanoparticles as contrast agents in magnetic resonance imaging using high-Tc superconducting quantum interference devices in microtesla magnetic fields,” Supercond. Sci. Technol., vol. 22, 025003(2009).
[22] H. C. Seton, J.S.M. Hutchison, D. M. Busell, “A 4.2 K receiver coil and SQUID amplifier used to improve the SNR of low-field magnetic resonance images of the human arm”,Meas. Sci. Technol. 8, 198 (1997).
[23] S. Kumar, R. Mathews, S. G.. Haupt, D.K. Lathrop, M. Takigawa, J. R. Rozen, S. L. Brown, R. H. Koch, “Nuclear magnetic resonance using a high temperature superconducting quantum interference device”Appl. Phys. Lett. 70, 1037 (1997).
[24] S. Kumar, W. F. Avrin, B. R. Whitecotton, “NMR of room temperature samples with a flux-locked dc SQUID＂ IEEE Trans. Magn. 32, 5261 (1996).
[25] K. Schlenga, R. F. McDemott, J. Clarke, R. E. de Souza, A. Wong-Foy, A. Pines, “Low-Field Magnetic Resonance Imaging with a High-Tc dc Superconducting Quantum Interference Device,＂ Appl. Phys. Lett. 75, 3695 (1999).
[26] N. Q. Fan, M. B. Heaney, J. Clarke, D. Newitt, L. L. Wald, E. L. Hahn, A. Bielecki, A. Pines, “Nuclear magnetic resonance with DC SQUID preamplifiers”IEEE Trans. Magn, vol. 25,1193(1989)
[27] M. A. Espy, A. N. Matlachov, P. L. Volegov, J. C. Mosher, and R. H. Kraus, Jr. “SQUID-based simultaneous detection of NMR and biomagnetic signals at ultra-low magnetic fields＂ IEEE Trans. Appl. Supercon. 15, 635 (2005).
[28] M. Burghoff, S. Hartwig, L. Trahms, and J. Bernarding, “Nuclear magnetic resonance in the nanoTesla range＂,Appl. Phys. Lett. 87, 054103 (2005)
[29] W. Myers, D. Slichter, M. Hatridge, S. Busch, M. Mößle, R. McDermott,A. Trabesinger, and J. Clarke, “Calculated signal-to-noise ratio of MRI detected with SQUIDs and Faraday detectors in fields from 10 μT to 1.5 T,” J. Magn. Reson., vol. 186, 182, 2007.
[30] V. S. Zotev, A. N. Matlachov, P. L. Volegov, H. J. Sandin, M. A. Espy,J. C. Mosher, A. V. Urbaitis, S. G. Newman, and R. H. Kraus, “Multichannel SQUID system for MEG and ultra-low-field MRI,” IEEE Trans.Appl. Supercond., vol. 17, 839, 2007.
[31] M .A. Bernstein, K. F. King and X. J. Zhou, “Handbook of MRI Pulse Sequences.＂ Elsevier Academic Press, 960 (2004)
[32] Joseph P. Hornak, Ph.D. (1996-2011),The Basics of MRI, 2013年7月3日取自於http://www.cis.rit.edu/htbooks/mri/
[33] I. Sasada and Y. Nakashim, “Planar coil system consisting of three coil pairs for producing a uniform magnetic field”, J. Appl. Phys. 99, 08D904 (2006)
[34] Vadim S. Zotev *, Petr L. Volegov, Andrei N. Matlashov, Michelle A. Espy, John C. Mosher, Robert H. Kraus Jr. “Parallel MRI at microtesla fields”, Journal of Magnetic Resonance 192 ,197(2008)
[35] 莊祖詮,可移動式低磁場核磁共振系統之研發,碩士論文,台北:國立台灣師範大學,光電科技研究所(2012)
[36] S. Godefroy, M. Fleury, F. Deflandre, and J.-P. Korb, “Temperature Effect on NMR Surface Relaxation in Rocks for Well Logging Applications ＂J. Phys. Chem. B,106 , 11183-11190 (2002)