Human Brain Proton Metabolite Mapping at Short TE

Summary

Principal Investigator: GERALD MATSON
Abstract: A major problem in quantification of proton metabolites obtained by high field magnetic resonance (MR) spectroscopic imaging (MRSI) at short TE is separating the metabolite resonances from the uneven and varying baseline Some of the baseline fluctuations are due to out-of-volume water and lipid signals, while other variations are due to the presence of macromolecules We propose a series of measures to improve the ability to separate metabolite and baseline signals, the most important of which involves obtaining a series of moderate signal-to noise (S/N) spectra at differing TE times with a sequence that includes closely spaced 180 degrees pulses (CP pulse train) to reduce J evolution for strongly coupled spins prior to acquisition This preserves the spectral patterns for strongly coupled resonances at the different TE values even though the signal amplitudes decay due to T2 relaxation Simultaneous fitting of the suite of spectra is expected to enable improved separation of metabolite signals from baseline, and to provide more reliable estimates of metabolite resonance areas A number of additional measures including 1) improved RF pulses, including improvement of hyperbolic secant pulses and a spin echo pulse cascade with immunity to B1 inhomogenicity for the CP pulse train, 2) improved methods of shimming, 3) improved MRSI acquisition sequences, 4) improved methods for processing of metabolite spectra, and 5) improvements for metabolite quantification in institutional units, based on coanalysis with tissue segmented structural MRI data, are planned Finally, a metabolite atlas of normal brain, reflecting regional metabolite levels and variations, will be developed This proposal is coordinated with the partner IRPG proposal for sharing of programs, pulses, data, and information to enhance the research at both sites.
Funding Period: 2002-09-30 - 2010-06-30
more information: NIH RePORT

Top Publications

  1. pmc Radiofrequency pulse designs for three-dimensional MRI providing uniform tipping in inhomogeneous B₁ fields
    Hui Liu
    Department of Veterans Affairs Medical Center, Center for Imaging of Neurodegenerative Diseases 114M, University of California, San Francisco, California, USA
    Magn Reson Med 66:1254-66. 2011
  2. pmc (1)H MRS detection of glycine residue of reduced glutathione in vivo
    Lana G Kaiser
    Varian Incorporated, Palo Alto, CA, USA
    J Magn Reson 202:259-66. 2010
  3. pmc RF pulses for in vivo spectroscopy at high field designed under conditions of limited power using optimal control
    Gerald B Matson
    Center for Imaging of Neurodegenerative Diseases 114M, Department of Veterans Affairs Medical Center, University of California, 4150 Clement Street, San Francisco, CA 94121, USA
    J Magn Reson 199:30-40. 2009
  4. pmc Numerical simulations of localized high field 1H MR spectroscopy
    Lana G Kaiser
    Northern California Institute for Research and Education, San Francisco, CA 97121, USA
    J Magn Reson 195:67-75. 2008
  5. pmc Measuring structural complexity in brain images
    Karl Young
    Department of Radiology, University of California San Francisco and Center for Imaging of Neurodegenerative Diseases, Department of Veterans Affairs Medical Center, San Francisco, CA 94121, USA
    Neuroimage 39:1721-30. 2008
  6. ncbi Spectral phase-corrected GRAPPA reconstruction of three-dimensional echo-planar spectroscopic imaging (3D-EPSI)
    Xiaoping Zhu
    Department of Radiology, University of California San Francisco, San Francisco, California, USA
    Magn Reson Med 57:815-20. 2007
  7. pmc Effects of Alzheimer disease on fronto-parietal brain N-acetyl aspartate and myo-inositol using magnetic resonance spectroscopic imaging
    Xiaoping Zhu
    Department of Radiology, VA Medical Center, University of California, San Francisco, CA 94121, USA
    Alzheimer Dis Assoc Disord 20:77-85. 2006
  8. pmc Robust analysis of short echo time (1)H MRSI of human brain
    X P Zhu
    Department of Radiology, University of California San Francisco, San Francisco, CA 94121, USA
    Magn Reson Med 55:706-11. 2006
  9. pmc Observation of coupled 1H metabolite resonances at long TE
    Brian J Soher
    Department of Radiology, University of Miami School of Medicine, Miami, Florida, USA
    Magn Reson Med 53:1283-7. 2005
  10. ncbi Summarizing complexity in high dimensions
    Karl Young
    Department of Radiology, University of California San Francisco, San Francisco, California 94121, USA
    Phys Rev Lett 94:098701. 2005

Scientific Experts

Detail Information

Publications10

  1. pmc Radiofrequency pulse designs for three-dimensional MRI providing uniform tipping in inhomogeneous B₁ fields
    Hui Liu
    Department of Veterans Affairs Medical Center, Center for Imaging of Neurodegenerative Diseases 114M, University of California, San Francisco, California, USA
    Magn Reson Med 66:1254-66. 2011
    ..Although the NSS pulses generate higher specific absorption rates and larger magnetization transfer effects than the rectangular pulses they replace, they nevertheless show promise for three-dimensional MRI experiments at high field...
  2. pmc (1)H MRS detection of glycine residue of reduced glutathione in vivo
    Lana G Kaiser
    Varian Incorporated, Palo Alto, CA, USA
    J Magn Reson 202:259-66. 2010
    ..This allows shorter acquisition times for in vivo human clinical studies...
  3. pmc RF pulses for in vivo spectroscopy at high field designed under conditions of limited power using optimal control
    Gerald B Matson
    Center for Imaging of Neurodegenerative Diseases 114M, Department of Veterans Affairs Medical Center, University of California, 4150 Clement Street, San Francisco, CA 94121, USA
    J Magn Reson 199:30-40. 2009
    ..Finally, the optimal control routines and example RF pulses are made available for downloading...
  4. pmc Numerical simulations of localized high field 1H MR spectroscopy
    Lana G Kaiser
    Northern California Institute for Research and Education, San Francisco, CA 97121, USA
    J Magn Reson 195:67-75. 2008
    ..Numerical simulations that incorporate volume localization using experimental RF pulses are shown to be a powerful tool for generation of accurate metabolic basis sets for spectral fitting and for optimization of experimental parameters...
  5. pmc Measuring structural complexity in brain images
    Karl Young
    Department of Radiology, University of California San Francisco and Center for Imaging of Neurodegenerative Diseases, Department of Veterans Affairs Medical Center, San Francisco, CA 94121, USA
    Neuroimage 39:1721-30. 2008
    ..The results illustrate that the complexity estimation method, though general, is capable of providing interpretable diagnostic information...
  6. ncbi Spectral phase-corrected GRAPPA reconstruction of three-dimensional echo-planar spectroscopic imaging (3D-EPSI)
    Xiaoping Zhu
    Department of Radiology, University of California San Francisco, San Francisco, California, USA
    Magn Reson Med 57:815-20. 2007
    ..5 yields results very similar to those obtained by fully encoded 3D-EPSI, and is more accurate than conventional GRAPPA...
  7. pmc Effects of Alzheimer disease on fronto-parietal brain N-acetyl aspartate and myo-inositol using magnetic resonance spectroscopic imaging
    Xiaoping Zhu
    Department of Radiology, VA Medical Center, University of California, San Francisco, CA 94121, USA
    Alzheimer Dis Assoc Disord 20:77-85. 2006
    ..However, the NAA and mI changes are not correlated with each other, suggesting that they represent different processes that might help staging of AD...
  8. pmc Robust analysis of short echo time (1)H MRSI of human brain
    X P Zhu
    Department of Radiology, University of California San Francisco, San Francisco, CA 94121, USA
    Magn Reson Med 55:706-11. 2006
    ..Back-to-back MRSI studies on 10 healthy volunteers showed that mean spectra markedly improved reliability of brain metabolite measurements, most notably for myo-inositol, as compared to regression methods...
  9. pmc Observation of coupled 1H metabolite resonances at long TE
    Brian J Soher
    Department of Radiology, University of Miami School of Medicine, Miami, Florida, USA
    Magn Reson Med 53:1283-7. 2005
    ..The spectral analysis for spectra with longer TE times also showed less variability due the higher metabolite SNR, simpler spectral patterns, and the decreased baseline contributions...
  10. ncbi Summarizing complexity in high dimensions
    Karl Young
    Department of Radiology, University of California San Francisco, San Francisco, California 94121, USA
    Phys Rev Lett 94:098701. 2005
    ..An example of the use of these tools to identify state evolution in the brain, an archetypal, complex biophysical system, serves as an illustration...