Abstract
The proper design of birdcage (BC) coils plays a very important role in the acquisition of highresolution magnetic resonance imaging (MRI) of small animals such as rodents. In this context, we investigate multiple-leg (8-, 16-, 32-, 64-, and 128-leg) BC coils operating at ultra-high fields (UHF) of 7.0 T and 11.7 T and a high-field (HF) of 4.7 T for rodent magnetic resonance imaging (MRI). Primarily, Our study comparatively examines the parameters of the radiofrequency (RF) transmission (|B1 +|)-field, the magnetic flux (|B1|)-field, and RF power deposition (RF-PD) as functions of the number of BC-coil legs via finite-difference time-domain (FDTD) calculations under realistic loading conditions with a biological phantom. In particular, the specific ratio |E/B1 +| is defined for predicting RF-PD values in different coil structures. Our results indicate that the optimal number of legs of the BC coil can be chosen for different resonance frequencies of 200 MHz, 300 MHz, and 500 MHz and that this choice can be lead to superior |B1 +|-field intensity and |B1|-field homogeneity and decreased RF-PD. We believe that our approach to determining the optimal number of legs for a BC coil can contribute to rodent MR imaging.
Similar content being viewed by others
References
P. Marzola, F. Osculati and A. Sbarbati, Eur. J. Radiol. 48, 165 (2003).
N. Beckmann, T. Mueggler, P. R. Allegrini, D. Laurent and M. Rudin, Anat. Rec. 265, 85 (2001).
F. Hezel, P. Kellman, C. Thalhammer, C. Özerdem, W. Renz and T. Niendorf, Proc. Intl. Soc. Mag. Reson. Med. 19, 595 (Canada, 2011).
A. Graessl et al., Magn. Reson. Med. 72, 276 (2014).
Z. H. Cho, 7.0 Tesla MRI Brain Atlas: In-vivo Atlas with Cryomacrotome Correlation (Springer, Berlin, 2010).
K. Kang, C. A. Park, H. Lee, S. H. Kim, C. W. Park, Y. B. Kim and Z. H. Cho, Hypertension 54, 1050 (2009).
J. C. Goebel et al., Rheumatology 49, 1654 (2010).
H. Merkle, J. Pfeuffer and N. K. Logothetis, Proc. ESMRM 19, 425 (Cannes, 2002).
G. Gulsen, L. T. Muftuler and O. Nalcioglu, J. Magn. Reson. 156, 309 (2002).
C. Qian, I. S. Masad, J. T. Rosenberg, M. Elumalai, W. W. Brey, S. C. Grant and P. L. Gor’kov, J. Magn. Reson. 221, 110 (2012).
U. Katscher and P. Börnert, NMR Biomed. 19, 393 (2006).
K. L. Moody, N. A. Hollingsworth, F. Zhao, J. F. Nielsen, D. C. Noll, S. M. Wright and M. P. McDougall, J. Magn. Reson. 246, 62 (2014).
Y. Li, Z. Xie, Y. Pang, D. Vigneron and X. Zhang, Med. Phys. 38, 4086 (2011).
J. Larkman and R. G. Nunes, Phys. Med. Biol. 52, R15 (2007).
A. Deshmane, V. Gulani, M. A. Griswold and N. Seiberlich, J. Magn. Reson. Imaging 36, 55 (2012).
J. F. Glockner, H. H. Hu, D. W. Stanley, L. Angelos and K. King, Radiographics 25, 1279 (2005).
P. B. Roemer, W. A. Edelstein, C. E. Hayes, S. P. Souza and O. M. Mueller, Magn. Reson. Med. 16, 192 (1990).
D. J. Herlihy, A. Collins and J. Hajnal, Proc. Intl. Soc. Magn. Reson. Med. 10, 769 (Hawaii, 2002).
G. Gulsen, L. Muftuler, K. Sezen and O. Nalcioglu, Proc. Intl. Soc. Magn. Reson. Med. 9, 1101 (Scotland, 2001).
E. Hayes, W. A. Edelstein, J. F. Schenck, O. M. Mueller and M. Eash, J. Magn. Reson. 63, 622 (1985).
N. Chen, D. I. Hoult and V. J. Sank, J. Magn. Reson. 54, 324 (1983).
J. Mispelter, M. Lupu and A. Briguet, NMR Probeheads: For Biophysical and Biomedical Experiments (Imperial College Press, London, 2006).
K. H. Herrmann et al., Magn. Reson. Mater. Phys 25, 233 (2012).
Y. Pang, B. Wu and X. Zhang, Magn. Reson. Med. 45, 684 (2001).
M. Kozlov and R. Turner, Proc. IEEE EMBC 33, 547 (Boston, 2011).
M. Collins, S. Li and M. B. Smith, Magn. Reson. Med. 40, 847 (1998).
T. S. Ibrahim, R. Lee, B. A. Baertlein, Y. Yu and P. M. L. Robitaille, Magn. Reson. Imaging 18, 835 (2000).
C. Wang and G. X. Shen, J. Magn. Reson. Imaging 24, 439 (2006).
D. Brunner, N. Zanche, J. Froehlich, D. Baumann and K. P. Pruessmann, Proc. Intl. Soc. Magn. Reson. Med. 15, 448 (Berlin, 2007).
Y. Pang, B. Wu and X. Zhang, Proc. Intl. Soc. Magn. Reson. Med. 18, 47 (Stockholm, 2010).
Author information
Authors and Affiliations
Corresponding author
Additional information
These authors contributed equally to this work.
Rights and permissions
About this article
Cite this article
Seo, JH., Han, SD. & Kim, KN. Investigation of the B1 field distribution and RF power deposition in a birdcage coil as functions of the number of coil legs at 4.7 T, 7.0 T, and 11.7 T. Journal of the Korean Physical Society 66, 1822–1826 (2015). https://doi.org/10.3938/jkps.66.1822
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.3938/jkps.66.1822