Homodyne detection in magnetic resonance imaging.

Magnetic detection of complex images in magnetic resonance imaging (MRI) is immune to the effects of incidental phase variations, although in some applications information is lost or images are degraded. It is suggested that synchronous detection or demodulation can be used in MRI systems in place of magnitude detection to provide complete suppression of undesired quadrature components, to preserve polarity and phase information, and to eliminate the biases and reduction in signal-to-noise ratio (SNR) and contrast in low SNR images. The incidental phase variations in an image are removed through the use of a homodyne demodulation reference, which is derived from the image or the object itself. Synchronous homodyne detection has been applied to the detection of low SNR images, the reconstruction of partial k-space images, the simultaneous detection of water and lipid signals in quadrature, and the preservation of polarity in inversion-recovery images.

[1]  S. O. Rice,et al.  Statistical properties of a sine wave plus random noise , 1948, Bell Syst. Tech. J..

[2]  Glenn Milton Glasford.  Fundamentals of Television Engineering , 1955 .

[3]  D. Middleton.  An Introduction to Statistical Communication Theory , 1960 .

[4]  Ronald N. Bracewell,et al.  The Fourier Transform and Its Applications , 1966 .

[5]  Herbert Taub,et al.  Principles of communication systems , 1970 .

[6]  Rodger E. Ziemer,et al.  Principles of communications , 1976 .

[7]  P. V. van Dijk,et al.  Restoration of Signal Polarity in a Set of Inversion Recovery NMR Images , 1984, IEEE Transactions on Medical Imaging.

[8]  W. T. Dixon.  Simple proton spectroscopic imaging. , 1984, Radiology.

[9]  G. Bydder,et al.  Apparent changes of appearance of inversion‐recovery images , 1985, Magnetic resonance in medicine.

[10]  M. O’Donnell,et al.  NMR imaging in the presence of magnetic field inhomogeneities and gradient field nonlinearities. , 1985, Medical physics.

[11]  Z. Cho,et al.  Real‐value representation in inversion‐recovery NMR imaging by use of a phase‐correction method , 1986, Magnetic resonance in medicine.

[12]  Orhan Nalcioglu,et al.  Spectroscopic imaging by quadrature modulated echo time shifting , 1986 .

[13]  D. Feinberg,et al.  Halving MR imaging time by conjugation: demonstration at 3.5 kG. , 1986, Radiology.

[14]  J. Cuppen,et al.  Reducing MR imaging time by one-sided reconstruction , 1987 .

[15]  Z. H. Cho,et al.  Chemical‐shift imaging with large magnetic field inhomogeneity , 1987, Magnetic resonance in medicine.

[16]  Faster Magnetic Resonance Imaging by Use of 3-Quarter Matrix Data , 1987 .

[17]  D G Nishimura,et al.  Magnetic resonance angiography by selective inversion recovery using a compact gradient echo sequence , 1988, Magnetic resonance in medicine.

[18]  Reduced MR Acquisition Time with the CROCUS Technique , 1988, Journal of computer assisted tomography.

[19]  N. Pelc,et al.  Correction of spatially dependent phase shifts for partial Fourier imaging. , 1988, Magnetic resonance imaging.

[20]  T J Brosnan,et al.  Computing material‐selective projection images in MR , 1989, Magnetic resonance in medicine.

[21]  R Turner,et al.  Snapshot imaging at 0.5 t using echo‐planar techniques , 1989, Magnetic resonance in medicine.

[22]  W. Perman,et al.  Improved detectability in low signal-to-noise ratio magnetic resonance images by means of a phase-corrected real reconstruction. , 1989, Medical physics.

[23]  Partial k-space reconstruction for magnetic resonance angiography by selective inversion recovery , 1989, Images of the Twenty-First Century. Proceedings of the Annual International Engineering in Medicine and Biology Society,.

[24]  A M Aisen,et al.  Regional phase correction of inversion‐recovery MR images , 1990, Magnetic resonance in medicine.