title: Selective homonuclear polarization transfer for spectroscopic imaging of GABA at 7T.
abstract: We develop and implement a selective homonuclear polarization transfer method for the detection of 3.0 ppm C-4 GABA resonance by spectroscopic imaging in the human brain at 7T. This single shot method is demonstrated with simulations and phantoms, which achieves comparable efficiency of detection to that of J-difference editing. The macromolecule resonance that commonly co-edits with GABA is suppressed at 7T through use of a narrow band preacquisition suppression pulse. This technique is implemented in humans with an eight channel transceiver array and high degree B(0) shimming to measure supplementary motor area and thalamic GABA in controls (n = 8) and epilepsy patients (n = 8 total). We find that the GABA/N-acetyl aspartate ratio in the thalamus of control volunteers, well controlled and poorly controlled epilepsy patients are 0.053 ± 0.012 (n = 8), 0.090 ± 0.012 (n = 2), and 0.038 ± 0.009 (n = 6), respectively.
authors.affiliation: Department of Neurosurgery, Yale University School of Medicine, New Haven, Connecticut 06520, USA. Jullie.pan@yale.edu
authors.forename: J W
authors.initials: JW
authors.lastname: Pan
authors.forename: R B
authors.initials: RB
authors.lastname: Duckrow
authors.forename: D D
authors.initials: DD
authors.lastname: Spencer
authors.forename: N I
authors.initials: NI
authors.lastname: Avdievich
authors.forename: H P
authors.initials: HP
authors.lastname: Hetherington
mesh_terms: D000465:Algorithms; D001921:Brain / Q000378:metabolism*; D004827:Epilepsy / Q000378:metabolism*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D018377:Neurotransmitter Agents / Q000032:analysis*; D011522:Protons; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D005680:gamma-Aminobutyric Acid / Q000032:analysis
chemical_list: D018377:Neurotransmitter Agents; D011522:Protons; D005680:gamma-Aminobutyric Acid