Invivo Volume-Selective Metabolite Editing Via Correlated Z-Order

Volume‐selected H NMR spectroscopy was combined with spectral editing to selectively detect brain metabolites. The SPACE localization sequence was used to create a voxel of z‐magnetization which could then be edited for any scalar coupled metabolite by the use of selective excitation in the ECZOTIC sequence to generate longitudinal spin order. The sequence returns an edited signal with no intrinsic loss of magnetization. The method was applied to observe approximately 10 m M ethanol and 17 mM lactate in the brain of a dog. © 1990 Academic Press, Inc

On the Use of a Slice-Selective 270-Degrees Self-Refocusing Gaussian Pulse for Magnetic-Resonance-Imaging

Theoretical and experimental results are presented demonstrating that the slice intensity resulting from a self‐refocusing 270° Gaussian pulse (L. Elmsley and G. Bodenhausen, Magn. Reson. in Med. 10, 273, 1989) is approximately 60% of that following an appropriately refocused 90° Gaussian pulse

Use of High-Resolution Invivo Volume Selected H-1-Magnetic Resonance Spectroscopy to Investigate Leukemia in Humans

In vivo high resolution volume-selected H magnetic resonance spectroscopy of human tibia has been undertaken using spatial coordinates obtained from magnetic resonance images. Adult tibial marrow has a H spectrum rich in fatty acid resonances and is readily distinguished from the H spectra of surrounding leg muscle. In all four leukemic patients examined, infiltration of fat cells of tibial marrow by proliferating cells rich in mobile HO protons was evident by magnetic resonance imaging. Selective examination of volumes of tibial marrow (1 cm) by H magnetic resonance spectroscopy confirmed marked differences in the H spectra of marrow from these patients. Increases in the HO peak of the H spectra were correlated with infiltration of blast cells and lack of control of the neoplastic disease. These studies are the first to report the use of volume selected magnetic resonance spectroscopy to selectively monitor leukemia in humans

Invivo High-Resolution Volume-Selected Proton Spectroscopy and T1 Measurements in the Dog Brain

Successful in vivo NMR spectroscopy requires a combination of techniques to address the problems of volume selection, water suppression, and resolution. All this needs to be done in the very heterogeneous environment found in living organisms. Previously published techniques are used to obtain H spectra from a dog brain, observing metabolites with concentrations below 1 mM. Measurements of spin‐lattice relaxation times (T) are also presented. The H relaxation times are long (T > 1.0 s) yielding information about the fluidity of the molecular environment. Comments are made concerning the achievable linewidth in vivo and the deficiencies that phase‐encoding spectroscopic methods may have in obtaining high‐resolution H spectra. © 1989 Academic Press, Inc