Abstract：
:Localized high-resolution diffusion tensor images (DTI) from the midbrain were obtained using reduced field-of-view (rFOV) methods combined with SENSE parallel imaging and single-shot echo planar (EPI) acquisitions at 7T. This combination aimed to diminish sensitivities of DTI to motion, susceptibility variations, and EPI artifacts at ultra-high field. Outer-volume suppression (OVS) was applied in DTI acquisitions at 2- and 1-mm(2) resolutions, b=1000s/mm(2), and six diffusion directions, resulting in scans of 7- and 14-min durations. Mean apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were measured in various fiber tract locations at the two resolutions and compared. Geometric distortion and signal-to-noise ratio (SNR) were additionally measured and compared for reduced-FOV and full-FOV DTI scans. Up to an eight-fold data reduction was achieved using DTI-OVS with SENSE at 1mm(2), and geometric distortion was halved. The localization of fiber tracts was improved, enabling targeted FA and ADC measurements. Significant differences in diffusion properties were observed between resolutions for a number of regions suggesting that FA values are impacted by partial volume effects even at a 2-mm(2) resolution. The combined SENSE DTI-OVS approach allows large reductions in DTI data acquisition and provides improved quality for high-resolution diffusion studies of the human brain.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Wargo CJ,Gore JCdoi
10.1016/j.mri.2013.01.013subject
Has Abstractpub_date
2013-07-01 00:00:00pages
810-9issue
6eissn
0730-725Xissn
1873-5894pii
S0730-725X(13)00043-Xjournal_volume
31pub_type
杂志文章abstract：:The objective of this study was to describe magnetic resonance (MR) findings with a 1.5T imager for hepatic parenchymal changes after proton beam radiotherapy. Thirty-two patients who received proton radiotherapy with doses of 50-87 Gy underwent MR imaging 1-75 months (mean 22 months) after the start of irradiation. A...
journal_title：Magnetic resonance imaging
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(97)82763-4
更新日期：1997-01-01 00:00:00
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journal_title：Magnetic resonance imaging
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)92031-1
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
doi：10.1016/0730-725x(90)90137-q
更新日期：1990-01-01 00:00:00
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更新日期：2017-01-01 00:00:00
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pub_type： 杂志文章
doi：10.1016/0730-725x(94)90079-7
更新日期：1994-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(96)00380-3
更新日期：1997-01-01 00:00:00
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journal_title：Magnetic resonance imaging
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doi：10.1016/s0730-725x(96)00342-6
更新日期：1997-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)91557-1
更新日期：1994-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(01)00389-7
更新日期：2001-06-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2013.04.001
更新日期：2013-09-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2016.05.002
更新日期：2016-10-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(99)00051-x
更新日期：1999-09-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.10.012
更新日期：2008-05-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2003.09.005
更新日期：2004-02-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(92)90409-s
更新日期：1992-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(93)90069-p
更新日期：1993-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(95)02097-d
更新日期：1996-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(87)90481-4
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(97)00311-1
更新日期：1998-05-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
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更新日期：2015-09-01 00:00:00
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journal_title：Magnetic resonance imaging
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doi：10.1016/j.mri.2011.04.011
更新日期：2011-09-01 00:00:00
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journal_title：Magnetic resonance imaging
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更新日期：1993-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.06.008
更新日期：2008-02-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2015.08.004
更新日期：2015-12-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2014.10.002
更新日期：2015-01-01 00:00:00
abstract：:The ability to evaluate empirical diffusion MRI acquisitions for quality and to correct the resulting imaging metrics allows for improved inference and increased replicability. Previous work has shown promise for estimation of bias and variance of generalized fractional anisotropy (GFA) but comes at the price of compu...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2019.03.021
更新日期：2019-06-01 00:00:00
abstract：:Magnetic resonance spectroscopy (MRS) is ideally suited for physiology-neurochemistry experiments with the living brain and particularly for studies on the primary visual cortex (striate cortex or area V1). Yet, the highly convoluted form of the human V1 has thus far prevented the performance of MRS investigations tha...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.03.008
更新日期：2007-07-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)92534-8
更新日期：1994-01-01 00:00:00
