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2012-05-12
Comprehensive Analysis of Lenz Effect on the Artificial Heart Valves During Magnetic Resonance Imaging
By
Progress In Electromagnetics Research, Vol. 128, 1-17, 2012
Abstract
This work presents results of a comprehensive analysis of the Lenz effect due to motion of artificial heart valves during magnetic resonance imaging. The interaction of rotating metallic heart valves with magnetic fields is studied by performing a time-domain analysis of the corresponding electromagnetic problem. We applied the finite element method (FEM) to solve the T-Ω formulation of Maxwell equations in two cases: first, for metallic disks located in the high intensity homogenous field of the magnet iso-center, and second, disks located in the non-uniform fringe field of the bore entrance. We showed that for valves with full solid disks (such as Starr-Edwards 6500) located in the magnet iso-center, the magnitude of adverse forces can be comparable to the forces applied by the beating heart. However, for rings which consist of multiply connected conductive regions, skin effect and proximity effect counteract, which leads to a diminished magnetic force. Results of this study show that mechanical heart valves with strengthening rings {may} be considered safe even under ultra-high imaging conditions with field intensities as high as 10 T. However, heart valves with full conducting disks should be considered as a contraindication to MR imaging.
Citation
Laleh Golestanirad, Emad Dlala, Graham Wright, Juan Mosig, and Simon J. Graham, "Comprehensive Analysis of Lenz Effect on the Artificial Heart Valves During Magnetic Resonance Imaging," Progress In Electromagnetics Research, Vol. 128, 1-17, 2012.
doi:10.2528/PIER12031505
References

1. Pennell, D., U. Sechtem, C. Higgins, W. Manning, G. Pohost, F. Rademakers, A. van Rossum, L. Shaw, and E. Yucel, "Clinical indications for cardiovascular magnetic resonance (CMR): Consensus panel report," J. Cardiovasc Magn. Reson., Vol. 6, No. 4, 727-765, 2004.
doi:10.1081/JCMR-200038581

2. Mavrogeni, S., F. Rademakers, and D. Cokkinos, "Clinical application of cardiovascular magnetic resonance," Hellenic J. Cardiol., Vol. 45, 401-405, 2004.

3. Roguin, A. and D. Goldsher, "Magnetic resonance imaging and implantable cardiac electronic devices: It's not what we can do,it's what we should do," Isr. Med. Assoc. J., Vol. 12, No. 7, 436-438, 2008.

4. Kalin, R. and M. Stanton, "Current clinical issues for MRI scanning of pacemaker and defibrillator patients," Pacing Clin.Electrophysiol., Vol. 28, 326-328, 2005.
doi:10.1111/j.1540-8159.2005.50024.x

5. Shellock, F. and S. Morisoli, "Ex vivo evaluation of ferromagnetism, heating, and artifacts produced by heart valve prostheses exposed to a 1.5T MR system," J. Magn. Reson. Imaging, Vol. 4, 756-758, 1994.
doi:10.1002/jmri.1880040521

6. Edwards, M., K. Taylor, and F. Shellock, "Prosthetic heart valves:Evaluation of magnetic field interactions, heating and artifacts at 1.5 T," J. Magn. Reson. Imaging, Vol. 12, 363-369, 2000.
doi:10.1002/1522-2586(200008)12:2<363::AID-JMRI21>3.0.CO;2-3

7. Soulen, R., T. Budinger, and C. Higgins, "Magnetic resonance imaging of prosthetic heart valves," Radiology, Vol. 154, 705-707, 1985.

8. Condon, B. and D. Hadley, "Potential MR hazard to patients with metallic heart valves: The lenz effect," J. Magn. Reson. Imaging, Vol. 12, 171-176, 2000.
doi:10.1002/1522-2586(200007)12:1<171::AID-JMRI19>3.0.CO;2-W

9. Robertson, N. M., M. Diaz-Gomez, and B. Condon, "Estimation of torque on mechanical heart valves due to magnetic resonance imaging including an estimation of the significance of the lenz effect using a computational model," Phys. Med. Biol., Vol. 45, 3793-3807, 2000.
doi:10.1088/0031-9155/45/12/320

10. Garrett, M. W., "Thick cylindrical coil systems for strong magnetic fields with field or gradient homogeneities of the 6th to 20th order," Journal of Applied Physics, Vol. 38, No. 6, 2563-2586, 1967.
doi:10.1063/1.1709950

11. Zhao, H. and S. Crozier, "A design method for superconducting MRI magnets with ferromagnetic material," Meas. Sci. Technol., Vol. 13, 2047, 2002.

12. Kalafala, A. K. and S. Crozier, "Optimized configurations for actively shielded magnetic resonance imaging magnets," IEEE Tran. Magn., Vol. 27, No. 2, 1696-1699, 1991.
doi:10.1109/20.133515

13. Sinha, G., R. Sundararaman, and G. Singh, "Design concepts of optimized MRI magnet," IEEE Tran. Magn., Vol. 44, No. 10, 2351-2360, 2008.
doi:10.1109/TMAG.2008.2001843

14. Ansys Product Suit. "Maxwell 3D,", http://www.ansoft.com/pro-ducts/em/maxwell/, 2011.

15. Henneron, T., Y. L. Menach, F. Piriou, O. Moreau, S. Clnet,J. Ducreux, J. Vrit, J. Villeneuve, and E. Nationale, "Source field computation in NDT applications," IEEE Tran. Magn., Vol. 43, No. 4, 1785-1788, 2007.
doi:10.1109/TMAG.2007.892522

16. Lynch, W. and Implants, Van Vostrand Reinhold, 48-94, New York, 1982.

17. Chandran, K., B. Khalighi, and C.-J. Chen, "Experimental study of physiological pulsatile flow past valve prostheses in a modeof of human aorta-II. Tilting disc valves and the effect of orientation," Journal of Biomechanics, Vol. 18, No. 10, 773-780, 1985.
doi:10.1016/0021-9290(85)90052-1

18. Ren, Z., "T-omega formulation for eddy-current problems in multiply connected regions," IEEE Tran. Magn., Vol. 38, No. 2, 557-560, 2002.
doi:10.1109/20.996146

19. Zhou, P., W. N. Fu, D. Lin, D. Stanton, and Z. J. Cendes, "Numerical modeling of magnetic devices," IEEE Tran. Magn., Vol. 40, No. 4, 1803-1809, 2004.
doi:10.1109/TMAG.2004.830511

20. Crozier, S., "Compact MRI magnet design by stochastic optimization," J. Magn. Reson., Vol. 127, 233-237, 1997.
doi:10.1006/jmre.1997.1200

21. Morgan, P. N., S. M. Conolly, and A. Macovski, "Resistive homogeneous MRI magnet design by matrix subset selection," Magn. Reson. Med., Vol. 41, No. 6, 1221-1229, 1999.
doi:10.1002/(SICI)1522-2594(199906)41:6<1221::AID-MRM19>3.0.CO;2-E

22. Thompson, M. R., R. W. Brown, and V. C. Srivastava, "An inverse approach to the design of MRI main magnets," IEEE Tran. Magn., Vol. 30, No. 1, 108-112, 1994.
doi:10.1109/20.272522

23. Zhao, H., S. Crozier, and D. M. Doddrell, "Asymmetric MRI magnet design using a hybrid numerical method," J Magn. Reson., Vol. 141, No. 2, 340-346, 1999.
doi:10.1006/jmre.1999.1924

24. Ravaud, R. and G. Lemarquand, "Magnetic field in MRI yokeless devices: Analytical approach," Progress In Electromagnetics Research, Vol. 94, No. 2, 327-341, 2009.
doi:10.2528/PIER09061205