Discrimination between neurochemical and macromolecular signals in human frontal lobes using short echo time proton magnetic resonance spectroscopy.

Magnetic resonance spectra from large (35 cm3) frontal lobe voxels in vivo were analyzed using LCModel, with and without subtraction of a "metabolite nulled" spectrum with an inversion time of 650 ms to characterize the macromolecule baseline. Baseline subtraction decreased the signal to noise ratio (SNR), but improved the reliability of LCModel quantification of most metabolites, as reflected in the Cramer-Rao lower bounds, in particular for glutamate and glutamine. The reported concentrations increased for glutamine, creatine, and lactate, and decreased for glutamate, myo-inositol and NAAG, but the sum of all metabolites remained constant, as did the standard deviation of the concentrations in the control group. Macromolecule subtraction is worthwhile when SNR is high, as in the characterization of normal-appearing tissue in the brain.

[1]  G J Barker,et al.  Quantitative analysis of short echo time 1H‐MRSI of cerebral gray and white matter , 2000, Magnetic resonance in medicine.

[2]  U. Klose,et al.  Reliable detection of macromolecules in single‐volume 1H NMR spectra of the human brain , 2001, Magnetic resonance in medicine.

[3]  K. Behar,et al.  Analysis of macromolecule resonances in 1H NMR spectra of human brain , 1994, Magnetic resonance in medicine.

[4]  G. Barker,et al.  Detection of myelin breakdown products by proton magnetic resonance spectroscopy , 1993, The Lancet.

[5]  J S Duncan,et al.  Short echo time single‐voxel 1H magnetic resonance spectroscopy in magnetic resonance imaging–negative temporal lobe epilepsy: Different biochemical profile compared with hippocampal sclerosis , 1999, Annals of neurology.

[6]  K. Behar,et al.  Short echo time proton magnetic resonance spectroscopic imaging of macromolecule and metabolite signal intensities in the human brain , 1996, Magnetic resonance in medicine.

[7]  C Gössl,et al.  Improved analysis of 1H‐MR spectra in the presence of mobile lipids , 2001, Magnetic resonance in medicine.

[8]  Wolfgang Grodd,et al.  Parameterized evaluation of macromolecules and lipids in proton MR spectroscopy of brain diseases , 2003, Magnetic resonance in medicine.

[9]  Jullie W Pan,et al.  2D 1H spectroscopic imaging of the human brain at 4.1 T , 1994, Magnetic resonance in medicine.

[10]  U Klose,et al.  Elimination of residual lipid contamination in single volume proton MR spectra of human brain. , 1999, Magnetic resonance imaging.

[11]  John S Duncan,et al.  A Proton Magnetic Resonance Spectroscopy Study of Metabolites in the Occipital Lobes in Epilepsy , 2003, Epilepsia.

[12]  S. Provencher Estimation of metabolite concentrations from localized in vivo proton NMR spectra , 1993, Magnetic resonance in medicine.

[13]  Michael Erb,et al.  Proton magnetic resonance spectroscopy with metabolite nulling reveals regional differences of macromolecules in normal human brain , 2002, Journal of magnetic resonance imaging : JMRI.

[14]  I. Fried,et al.  In vivo measurements of glutamine+ glutamate (Glx) and N‐acetyl aspartate (NAA) levels in human partial epilepsy , 2000, Acta neurologica Scandinavica.

[15]  J. Slotboom,et al.  Quantitative 1H‐magnetic resonance spectroscopy of human brain: Influence of composition and parameterization of the basis set in linear combination model‐fitting , 2002, Magnetic resonance in medicine.

[16]  Roland Kreis,et al.  Development of the human brain: In vivo quantification of metabolite and water content with proton magnetic resonance spectroscopy , 1993, Magnetic resonance in medicine.

[17]  R. Mattson,et al.  Initial Observations on Effect of Vigabatrin on In Vivo 1H Spectroscopic Measurements of γ‐Aminobutyric Acid, Glutamate, and Glutamine in Human Brain , 1995, Epilepsia.

[18]  J. Knight‐Scott,et al.  Application of multiple inversion recovery for suppression of macromolecule resonances in short echo time (1)H NMR spectroscopy of human brain. , 1999, Journal of magnetic resonance.

[19]  Wolfgang Grodd,et al.  Proton MRS in Kennedy disease: Absolute metabolite and macromolecular concentrations , 2002, Journal of magnetic resonance imaging : JMRI.

[20]  B J Soher,et al.  Automated spectral analysis II: Application of wavelet shrinkage for characterization of non‐parameterized signals , 1998, Magnetic resonance in medicine.

[21]  G B Matson,et al.  Short echo time multislice proton magnetic resonance spectroscopic imaging in human brain: metabolite distributions and reliability. , 2001, Magnetic resonance imaging.

[22]  U Klose,et al.  Proton MR spectroscopy with metabolite-nulling reveals elevated macromolecules in acute multiple sclerosis. , 2001, Brain : a journal of neurology.