Sensing and Imaging

, 15:98 | Cite as

Top-Level System Designs for Hybrid Low-Field MRI–CT with Potential of Pulmonary Imaging

  • Venkata R. Yelleswarapu
  • Fenglin Liu
  • Wenxiang Cong
  • Ge Wang
Original Paper
Part of the following topical collections:
  1. Topical Collection: Hybrid Imaging and Image Fusion


We previously discussed “omni-tomography”, but intrinsic conflicts between the magnetic fields of the MRI and the X-ray tube within the CT are inherent. We propose that by using low-field MRI with a negligible fringe field at the site of the CT source, it is possible to create a CT–MRI system with minimal interference. Low field MRI is particularly useful for lung imaging, where hyperpolarized gas can enhance the signal. Three major designs were considered and simulated, with modifications in coil design and axis allowing for further variation. The first uses Halbach arrays to minimize magnetic fields outside, the second uses solenoids pairs with active shielding, and the third uses a rotating compact MRI–CT. Each system is low field, which may allow the implementation of a standard rotating CT. Both structural and functional information can be acquired simultaneously for a true hybrid image with matching temporal and spatial image acquisition.


Computed tomography Hybrid combination Interior tomography Low field Lung imaging Magnetic resonance imaging 


  1. 1.
    Hopkins, Susan. (2007). Advances in magnetic resonance imaging of lung physiology. Journal of Applied Physiology, 102, 1244–1254.CrossRefGoogle Scholar
  2. 2.
    Wen, Z., Fahrig, R., Conolly, S., & Pelc, N. J. (2007). Investigation of electron trajectories of an x-ray tube in magnetic fields of MR scanners. Medical Physics, 34, 2048–2059.CrossRefGoogle Scholar
  3. 3.
    Wen, Z., Fahrig, R., & Pelc, N. J. (2005). Robust x-ray tubes for use within magnetic fields of MR scanners. Medical Physics, 32, 2327–2336.CrossRefGoogle Scholar
  4. 4.
    Brzozowski, L., et al. (2006). Compatibility of interventional x-ray and magnetic resonance imaging: Feasibility of a closed bore XMR (CBXMR) system. Medical Physics, 33, 3033–3045.CrossRefGoogle Scholar
  5. 5.
    Lillaney, P., Fahrig, R., et al. (2013). Novel motor design for rotating anode x-ray tubes operating in the fringe field of a magnetic resonance imaging system. Medical Physics, 40, 022302. doi: 10.1118/1.4773313.CrossRefGoogle Scholar
  6. 6.
    Tsai, L., et al. (2008). An open-access, very-low-field MRI system or posture-dependent 3He human lung imaging. Journal of Magnetic Resonance, 193, 274–285.CrossRefGoogle Scholar
  7. 7.
    Yu, H. Y., & Wang, G. (2009). Compressed sensing based interior tomography. Physics in Medicine & Biology, 54, 2791–2805.CrossRefGoogle Scholar
  8. 8.
    Ye, Y. B., Yu, H. Y., Wei, Y. C., & Wang, G. (2007). A general local reconstruction approach based on a truncated Hilbert transform. International Journal of Biomedical Imaging, 2007. doi: 10.1155/2007/63634.
  9. 9.
    Yu, H. Y., & Wang, G. (2009). Compressed sensing based Interior tomography. Physics in Medicine & Biology, 54, 2791–2805.CrossRefGoogle Scholar
  10. 10.
    Yu, H. Y., Yang, J. S., Jiang, M., & Wang, G. (2009). Supplemental analysis on compressed sensing based interior tomography. Physics in Medicine & Biology, 54, N425–N432.CrossRefGoogle Scholar
  11. 11.
    Yu, H. Y., Ye, Y. B., & Wang, G. (2008). Local reconstruction using the truncated Hilbert transform via singular value decomposition. Journal of X-Ray Science and Technology, 16, 243–251.Google Scholar
  12. 12.
    Wang, G., Zhang, J., Gao, H., Weir, V., Yu, H., et al. (2012). Towards omni-tomography—Grand fusion of multiple modalities for simultaneous interior tomography. PLoS ONE, 7(6), e39700. doi: 10.1371/journal.pone.0039700.CrossRefGoogle Scholar
  13. 13.
    Goldstein, T., & Osher, S. (2009). The split Bregman method for L1-regularized problems. SIAM Journal on Imaging Sciences, 2(2), 323–343.MathSciNetCrossRefzbMATHGoogle Scholar
  14. 14.
    Jones, M. (2012). A transportable magnetic resonance imaging system for in situ measurements of living trees: The Tree Hugger. Journal of Magnetic Resonance, 218, 133–140.CrossRefGoogle Scholar
  15. 15.
    Windt, C., Soltner, H., Dusschoten, D., & Blumler, P. (2011). A portable Halbach magnet that can be opened and closed without force: The NMR-CUFF. Journal of Magnetic Resonance, 208(1), 27–33.CrossRefGoogle Scholar
  16. 16.
    Wroblewsi, P. (2011). Mandhala magnet for ultra low-field MRI. IEEE. doi: 10.1109/IST.2011.5962203.
  17. 17.
    Aubin, J., & Fallone, B. (2010). Mangetic decouping of the linac in a low field biplanar linac-MRI. Medical Physics, 37(9), 4755–4761.CrossRefGoogle Scholar
  18. 18.
    Tadic, T. (2010). Design and optimization of a novel bored biplanar permanent-magnet assembly for hybrid magnetic resonance imaging systems. IEEE Transactions on Magnetics, 46, 12.CrossRefGoogle Scholar
  19. 19.
    Raich, H. (2004). Design and construction of a dipolar Halbach array with a homogenous field from identical bar magnets: NMR mandhalas. Concepts in Magnetic Resonance Part B, 23B(1), 16–25.MathSciNetCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.BMEBoston UniversityBostonUSA
  2. 2.CBIS/BMERensselaer Polytechnic InstituteTroyUSA
  3. 3.Key Lab of Optoelectronic Technology and System, Ministry of EducationChongqing UniversityChongqingChina

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