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Titolo:
High-resolution fMRI using multislice partial k-space GR-EPI with cubic voxels
Autore:
Hyde, JS; Biswal, BB; Jesmanowicz, A;
Indirizzi:
Med Coll Wisconsin, Biophys Res Inst, Milwaukee, WI 53226 USA Med Coll Wisconsin Milwaukee WI USA 53226 s Inst, Milwaukee, WI 53226 USA
Titolo Testata:
MAGNETIC RESONANCE IN MEDICINE
fascicolo: 1, volume: 46, anno: 2001,
pagine: 114 - 125
SICI:
0740-3194(200107)46:1<114:HFUMPK>2.0.ZU;2-#
Fonte:
ISI
Lingua:
ENG
Soggetto:
SPIN-LATTICE RELAXATION; ECHO-PLANAR MRI; HUMAN-BRAIN; FUNCTIONAL CONNECTIVITY; MOTOR CORTEX; NMR; VISUALIZATION; SOFTWARE; SYSTEM; NOISE;
Keywords:
fMRI; neuroimaging; brain; physiological noise; BOLD contrast;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Clinical Medicine
Life Sciences
Citazioni:
30
Recensione:
Indirizzi per estratti:
Indirizzo: Hyde, JS Med Coll Wisconsin, Biophys Res Inst, 8701 Watertown Plank Rd, Milwaukee, WI 53226 USA Med Coll Wisconsin 8701 Watertown Plank Rd Milwaukee WI USA 53226
Citazione:
J.S. Hyde et al., "High-resolution fMRI using multislice partial k-space GR-EPI with cubic voxels", MAGN RES M, 46(1), 2001, pp. 114-125

Abstract

The premises of this work are: 1) the limit of spatial resolution in fMRI is determined by anatomy of the microcirculation; 2) because of cortical gray matter tortuosity, fMRI experiments should tin principle) be carried outusing cubic voxels; and 3) the noise in fMRI experiments is dominated by row-frequency BOLD fluctuations that are a consequence of spontaneous neuronal events and are pixel-wise dependent. A new model is proposed for fMRI contrast which predicts that the contrast-to-noise ratio (CNR) tends to be independent of voxel dimensions tin the absence of partial voluming of activated tissue), TE, and scanner bandwidth. These predictions have been tested at 3 T, and results support the model. Scatter plots of fMRI signal intensities and low-frequency fluctuations for activated pixels in a finger-tapping paradigm demonstrated a linear relationship between signal and noise thatwas independent of TE. The R-2 value was about 0.9 across eight subjects studied. The CNR tended to be constant across pixels within a subject but varied across subjects: CNR = 3.2 +/- 1.0. fMRI statistics at 20- and 40-ms TE values were indistinguishable, and TE values as short as IO ms were used successfully. Robust fMRI data were obtained across all subjects using 1 x 1 x 1 mm(3) cubic voxels with 10 contiguous slices, although 1.5 x 1.5 x 1.5 mm(3) was found to be optimum. Magn Reson Med 46:114-125, 2001, (C) 2001 Wiley-Liss, Inc.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 21/01/20 alle ore 07:01:22