Abstract




 
   

IJE TRANSACTIONS C: Aspects Vol. 32, No. 3 (March 2019) 393-399   

PDF URL: http://www.ije.ir/Vol32/No3/C/6-3029.pdf  
downloaded Downloaded: 25   viewed Viewed: 71

  STATIC COIL DESIGN CONSIDERATIONS FOR THE MAGNETIC RESONANCE IMAGING
 
M. Shiravi, B. Ganji and A. Shiravi
 
( Received: September 28, 2018 – Accepted in Revised Form: March 07, 2019 )
 
 

Abstract    One of the main challenges in developing magnetic resonance imaging (MRI) systems is to create a static coil that needs to generate magnetic field density along with the characteristics of optimal homogeneity and magnitude size. To do this, two N42 Block PMs are used and the iron core is designed and optimized in accordance with the dimensions of PM pieces using ANSYS Maxwell software. Then, all iron parts are lathed, the yoke pieces and pole spacers are welded. In addition, PM and pole pieces are installed. Finally, measurement is done by Lutron to evaluate the static coil performance.

 

Keywords    Magnetic Resonance Imaging; Permanent Magnet; Static Coil; Inhomogeneity

 

چکیده   

کی از چالش‌های اصلی در توسعه سیستم‌های MRI ساخت یک کویل استاتیکی برای تولید چگالی میدان مغناطیسی با ویژگی‌های یکنواختی و اندازه دامنه بهینه می‌باشد. برای این منظور، دو قطعه مکعبی شکل آهنربا از نوع N42 استفاده می‌شود. در ادامه قطعات آهنی بوسیله CNC تراشکاری می‌شود و قطعات یوغ و ته قطب‌ها جوشکاری می‌گردد. سپس قطعات سرقطب و آهنربا نصب می‌شود. در نهایت، برای ارزیابی عملکرد کویل استاتیکی، میدان مغناطیسی بوسیله تسلامتر Lutron اندازه‌گیری می‌گردد.

References   

1. Cheng, Y. Y., Xia, L., and He, W., “Simulation and Optimization of a Permanent Magnet for Small-Sized MRI by Genetic Algorithm”, Applied Mechanics and Materials, Vol. 341–342, (2013), 577–580. 
2. Cheng, Y., He, W., Xia, L., Liu, F., “Design of Shimming Rings for Small Permanent MRI Magnet Using Sensitivity-Analysis-Based Particle Swarm Optimization Algorithm”, Journal of Medical and Biological Engineering, Vol. 35, No. 4, (2015), 448–454. 
3. Yao, Y., Koh, C. S., and Xie, D., “Three-Dimensional Optimal Shape Design of Magnetic Pole in Permanent Magnet Assembly for MRI Taking Account of Eddy Currents Due to Gradient Coil Field”, IEEE Transactions on Magnetics, Vol. 40, No. 2, (2004), 1164–1167. 
4. Wang, Q., Wang, H., Zheng, J., Dai, Y., Zhu, X., He, Q., Cheng, J., Chen, S., Song, S., Zhao, B., and Cui, C., “Open MRI Magnet With Iron Rings Correcting the Lorentz Force and Field Quality”,

IEEE Transactions on Applied Superconductivity, Vol. 24, No. 3, (2014), 1–5. 
5. Zhu, X., Wang, H., Wang, H., Li, Y. and Fang, Y., “A Novel Design Method of Passive Shimming for 0.7-T Biplanar Superconducting MRI Magnet”, IEEE Transactions on Applied Superconductivity, Vol. 26, No. 7, (2016), 1–5. 
6. Grau-Ruiz, D., Rigla, J.P., Díaz-Caballero, E., Nacev, A., Aguilar, A., Bellido, P., Conde, P., González-Montoro, A., González, A.J., Hernández, L., and Iborra, A., “Feasibility study of a gradient coil for a dedicated and portable single-sided MRI system”, In 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), IEEE, (2016), 1–4. 
7. Peña, A., “B0 Shimming using Pyrolytic Graphite,” Master thesis, Leiden University, Netherlands, (2017).
8. Yaghoobpour Tari, S., “Optimization of a Non-axial Magnet Design for a Hybrid Radiation Treatment and MR Imaging System”, Doctoral dissertation, University of Alberta, (2017).
9. Noguchi, S., Seungyong Hahn, and Iwasa, Y., “Passive Shimming for Magic-Angle-Spinning NMR”, IEEE Transactions on Applied Superconductivity, Vol. 24, No. 3, (2014), 1–4. 
10. Weggel, C. F. and Weggel, R. J., “New, ‘Super-Open,’ MRI, and MRT Magnets”, IEEE Transactions on Applied Superconductivity, Vol. 24, No. 3, (2014), 1–5. 
11. Punzo, V., Besio, S., Pittaluga, S., and Trequattrini, A., “MRI Magnet Pole Plate Optimization Method by Fourier Decomposition”, IEEE Transactions on Applied Superconductivity, Vol. 22, No. 3, (2012), 4401804–4401804. 
12. Wu, C., Guo, J., Chen, C., Yan, G., and Li, C., “Optimal Design and Test of Main Magnet in Superconducting MRI”, IEEE Transactions on Applied Superconductivity, Vol. 20, No. 3, (2010), 1810–1813. 
13. Ren, Z., Xie, D., and Li, H., “Study on shimming method for open permanent magnet of MRI”, Progress In Electromagnetics Research M, Vol. 6, (2009), 23–34. 
14. Zimmerman, C.L., “Low-field classroom nuclear magnetic resonance system,” Doctoral dissertation, Massachusetts Institute of Technology, (2010).


Download PDF 



International Journal of Engineering
E-mail: office@ije.ir
Web Site: http://www.ije.ir