Research Article

Performance evaluation of a 32-element head array with respect to the ultimate intrinsic SNR

  1. Riccardo Lattanzi1,
  2. Aaron K. Grant2,3,
  3. Jonathan R. Polimeni4,5,
  4. Michael A. Ohliger6,
  5. Graham C. Wiggins1,
  6. Lawrence L. Wald4,5,
  7. Daniel K. Sodickson1,*

Article first published online: 10 NOV 2009

DOI: 10.1002/nbm.1435

Issue

NMR in Biomedicine

NMR in Biomedicine

Volume 23, Issue 2, pages 142–151, February 2010

Additional Information

How to Cite

Lattanzi, R., Grant, A. K., Polimeni, J. R., Ohliger, M. A., Wiggins, G. C., Wald, L. L. and Sodickson, D. K. (2010), Performance evaluation of a 32-element head array with respect to the ultimate intrinsic SNR. NMR in Biomedicine, 23: 142–151. doi: 10.1002/nbm.1435

Author Information

  1. 1

    Center for Biomedical Imaging, Department of Radiology, New York University Langone Medical Center, New York, NY, USA

  2. 2

    Division of Magnetic Resonance Research, Department of Radiology, Beth Israel Deaconess Medical Center, Boston, MA, USA

  3. 3

    Harvard Medical School, Boston, MA, USA

  4. 4

    MGH-HMS-MIT Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA

  5. 5

    Department of Radiology, Massachusetts General Hospital, Boston, MA, USA

  6. 6

    School of Medicine, University of California, San Francisco, CA, USA

*Vice-Chair for Research, Department of Radiology, Director, Center for Biomedical Imaging, New York University Langone Medical Center, 660 First Avenue, Fourth Floor, New York, NY 10016, USA.

Publication History

  1. Issue published online: 22 FEB 2010
  2. Article first published online: 10 NOV 2009
  3. Manuscript Accepted: 6 JUL 2009
  4. Manuscript Revised: 23 JUN 2009
  5. Manuscript Received: 29 JAN 2009

Funded by

  • NIH. Grant Numbers: R01-EB000447, R01-EB002468, R01-1EB00684, P41-RR14075
  • Siemens Medical Solutions

SEARCH

SEARCH BY CITATION

ARTICLE TOOLS

Get PDF (385K)

Keywords:

  • Magnetic Resonance Imaging;
  • RF coils;
  • phased-array;
  • coil performance;
  • coil design;
  • parallel imaging;
  • electrodynamics;
  • ultimate intrinsic SNR

Graphical Abstract

Thumbnail image of graphical abstract

Absolute coil performance maps for a 32-element head array were generated based on the ratio of experimentally measured SNR to the ultimate intrinsic SNR, for different acceleration factors. A maximum performance of 85% was observed with a phantom whose electrical properties are consistent with values in the human brain. The method proposed here can be used both to evaluate coil designs and to guide the development of innovative receivers that may operate close to the optimum performance.

Abstract

The quality of an RF detector coil design is commonly judged on how it compares with other coil configurations. The aim of this article is to develop a tool for evaluating the absolute performance of RF coil arrays. An algorithm to calculate the ultimate intrinsic signal-to-noise ratio (SNR) was implemented for a spherical geometry. The same imaging tasks modeled in the calculations were reproduced experimentally using a 32-element head array. Coil performance maps were then generated based on the ratio of experimentally measured SNR to the ultimate intrinsic SNR, for different acceleration factors associated with different degrees of parallel imaging. The relative performance in all cases was highest near the center of the samples (where the absolute SNR was lowest). The highest performance was found in the unaccelerated case and a maximum of 85% was observed with a phantom whose electrical properties are consistent with values in the human brain. The performance remained almost constant for 2-fold acceleration, but deteriorated at higher acceleration factors, suggesting that larger arrays are needed for effective highly-accelerated parallel imaging. The method proposed here can serve as a tool for the evaluation of coil designs, as well as a tool to guide the development of original designs which may begin to approach the optimal performance. Copyright © 2009 John Wiley & Sons, Ltd.

Get PDF (385K)