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OJRad> Vol.4 No.2, June 2014
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Short Report: A Sponge Phantom Provides a Homogeneous k-Space Pattern at MRI

Abstract Full-Text HTML XML Download Download as PDF (Size:6811KB) PP. 195-200
DOI: 10.4236/ojrad.2014.42026    5,202 Downloads   6,075 Views  
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Jan Menke

Affiliation(s)

Radiology Center, University Hospital, Goettingen, Germany.

ABSTRACT

Background: The spectral coverage of magnetic resonance (MR) sequences can be well assessed in k-space. However, many objects do not provide high signal intensities in the peripheral k-space. Purpose: To experimentally find a phantom that provides a homogeneous spectral pattern also at the high spatial frequencies of the k-space periphery. Material and Methods: Different phantoms were imaged on a 1.5 Tesla magnet, and the resulting MR images were viewed in k-space after fast Fourier transform. Results: Firstly, phantoms with a homogeneous physical structure were studied with a T2-weighted MR sequence, but they provided an inhomogeneous k-space pattern with dominant central low-frequency components. Secondly, phantoms with an inhomogeneous physical structure were studied. In this group, a water-soaked sponge showed a relatively homogeneous k-space pattern also at high spatial frequencies, owing to the fine porous structure. This sponge phantom can also be soaked with Gadolinium chelates for T1-weighted MR imaging. Conclusion: A simple sponge phantom provides a homogeneous k-space pattern, owing to its fine porous structure. This could be utilized in MR sequence development and for viewing the spectral coverage of MR sequences in k-space.


KEYWORDS

Magnetic Resonance Imaging, Phantoms, Fourier Analysis, Spectrum Analysis, Computer-Assisted Image Processing

Cite this paper

Menke, J. (2014) Short Report: A Sponge Phantom Provides a Homogeneous k-Space Pattern at MRI. Open Journal of Radiology, 4, 195-200. doi: 10.4236/ojrad.2014.42026.

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1] Dhawan, A.P. (2003) Medical Image Analysis. IEEE Press, Wiley-Interscience, Hoboken, New Jersey, USA, 27-29, 37-39, 62-91, 111-174.
[2] Mezrich, R. (1995) A Perspective on k-Space. Radiology, 195, 297-315. http://dx.doi.org/10.1148/radiology.195.2.7724743
[3] Paschal, C.B. and Morris, H.D. (2004) K-Space in the Clinic. Journal of Magnetic Resonance Imaging, 19, 145-159. http://dx.doi.org/10.1002/jmri.10451
[4] Menke, J., Helms, G. and Larsen, J. (2010) Viewing the Effective k-Space Coverage of MR Images: Phantom Experiments with Fast Fourier Transform. Magnetic Resonance Imaging, 28, 87-94. http://dx.doi.org/10.1016/j.mri.2009.05.027
[5] Frigo, M. and Johnson, S.G. (2005) The Design and Implementation of FFTW3. Proceedings of IEEE, 93, 216-231. http://dx.doi.org/10.1109/JPROC.2004.840301

  
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