Journal ArticleDOI
The importance of the voxel size in clinical 1H spectroscopy of the human brain.
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TLDR
The results indicate that spectral changes seem to correlate with the metabolic state of the tumor rather than the tumor type, and the spectrum of a patient with multiple sclerosis suggests that even differentiation between tumors and other lesions might not be possible.Abstract:
It is demonstrated that it is possible to acquire two volume selective 1H NMR spectra of human brain in vivo, consisting of voxels of 1.5 × 1.5 × 1.5 cm3, within 14 min with a good S/N ratio. This is mainly achieved by the application of a PRESS sequence generating a spin-echo of the VOI at 135 ms in conjunction with the STABLE technique by which two spectra can be recorded in an interlaced mode. The Bo homogeneity over such small voxels is considerably higher than over larger voxels. With these methodological improvements it is possible to observe morphological heterogeneity of tumors. The results indicate that spectral changes seem to correlate with the metabolic state of the tumor rather than the tumor type. Additionally the spectrum of a patient with multiple sclerosis suggests that even differentiation between tumors and other lesions might not be possible.read more
Citations
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An In Vivo Proton Magnetic Resonance Spectroscopy Study of Schizophrenia Patients
Jeffrey A. Stanley,Peter C. Williamson,Dick J. Drost,R. Jane Rylett,Thomas J. Carr,Ashok Malla,R. Terry Thompson +6 more
TL;DR: The in vivo measurements of glutamate in the first-episode, drugnaive patients failed to provide convincing evidence for the involvement of the glutamatergic system in the dorsolateral prefrontal region.
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Noninvasive evaluation of malignancy of brain tumors with proton MR spectroscopy.
Hiroaki Shimizu,Toshihiro Kumabe,Teiji Tominaga,Takamasa Kayama,Kazushi Hara,Yasuki Ono,Koetsu Sato,Nobuyuki Arai,Satoru Fujiwara,Takashi Yoshimoto +9 more
TL;DR: Higher grades of brain tumors in this study were associated with higher Cho/reference and lower NAA/reference values, which suggest that clinical proton MR spectroscopy may help predict tumor malignancy.
Journal ArticleDOI
Direct absolute quantification of metabolites in the human brain with in vivo localized proton spectroscopy.
TL;DR: The results are concordant with the hypothesis, that the Cr and PCr resonance as observed by proton spectroscopy is due mainly to PCr, whereas Cr remains invisible by being attached to a larger molecule.
Journal ArticleDOI
Clinical tools for the 90s: magnetic resonance spectroscopy and metabolite imaging.
TL;DR: A new method of specific 31-phosphorus--phosphocreatine imaging provides information in partially denervated skeletal muscle and is expected to have applications in brain.
Journal ArticleDOI
The use of a priori knowledge to quantify short echo in vivo 1H MR spectra
TL;DR: In vivo 1H MR spectra of the prefrontal cortex acquired with the stimulated echo acquisition mode (STEAM) TE = 20 ms sequence were quantified to determine relative levels of cerebral metabolites to investigate the accuracy and precision of modeling these metabolites.
References
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Journal ArticleDOI
RARE imaging: a fast imaging method for clinical MR.
TL;DR: Based on the principles of echo imaging, a method is proposed to acquire sufficient data for a 256 × 256 image in from 2 to 40s, and the signal amplitudes of structures with long T2 are nearly the same as those in a conventional 2D FT experiment.
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Spatial localization in NMR spectroscopy in vivo.
TL;DR: DRESS is a simple and versatile localization procedure that is readily adaptable to spectral relaxation time measurements by adding inversion or spin-echo refocusing pulses or to in vivo solvent-suppressed spectroscopy of proton (1H) metabolites using a combination of chemical-selective RF pulses.
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Localized proton spectroscopy using stimulated echoes.
TL;DR: In this paper, a new method for spatially resolved NMR spectroscopy that takes advantage of stimulated echo signals is described, which is a single-step procedure minimizing rf power requirements and gradient switches.
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Localized high-resolution proton NMR spectroscopy using stimulated echoes: initial applications to human brain in vivo.
Jens Frahm,Harald Bruhn,Michael L. Gyngell,Klaus-Dietmar Merboldt,Wolfgang Hänicke,R. Sauter +5 more
TL;DR: Water‐suppressed localized proton NMR spectroscopy using stimulated echoes has been successfully applied to detect metabolites in the human brain in vivo and Cerebral lactate was found to be at a maximum concentration of 0.5 mM.
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Multiecho imaging sequences with low refocusing flip angles
TL;DR: In this article, a simple algorithm is presented, which permits recognition of all echos occurring in periodic multipulse sequences, and a RARE experiment based on these principles delivers sufficient signal intensity even with small refocusing flip angles.