Abstract：
:This work discusses the effect of sampling time on noise, signal-to-noise and contrast-to-noise ratios in magnetic resonance imaging. A simple imaging experiment is performed to demonstrate the effect of sampling time on noise, confirming theoretical expectations that doubling the sampling time while decreasing the read gradient strength by a factor of two reduces statistical noise to 1/square root 2 of its original level. This result suggests that sampling time should be maximized within the constraints of the pulse sequence: namely, that sampling time should be increased and read gradient strength decreased as TE is increased. Revised expressions for signal-to-noise and contrast-to-noise ratios are presented based on the assumption that sampling time increases linearly with echo delay time above a certain minimum TE value. The revised expressions are then used to derive new predictions of the interpulse delay times that maximize signal-to-noise and contrast-to-noise ratios in spin-echo imaging. It is demonstrated that sampling times are critical in determining whether T1-weighted or T2-weighted sequences produce superior tissue contrast in spin-echo imaging.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Hendrick REdoi
10.1016/0730-725x(87)90481-4subject
Has Abstractpub_date
1987-01-01 00:00:00pages
31-7issue
1eissn
0730-725Xissn
1873-5894pii
0730-725X(87)90481-4journal_volume
5pub_type
杂志文章abstract：PURPOSE:The detection of small parenchymal hepatic lesions identified by preoperative imaging remains a challenge for traditional pathologic methods in large specimens. We developed a magnetic resonance imaging (MRI) compatible localization device for imaging of surgical specimens aimed to improve identification and lo...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2016.11.021
更新日期：2017-04-01 00:00:00
abstract：:Traumatic brain injury (TBI) is one of the commonest causes of morbidity and mortality in the developed countries with posttraumatic epilepsy and functional disability being its major sequelae. The purpose of this study was to test the hypothesis whether the normal appearing adjacent gray and white matter regions on T...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
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更新日期：2003-10-01 00:00:00
abstract：:There is increasing interest in imaging short T2 species which show little or no signal with conventional magnetic resonance (MR) pulse sequences. In this paper, we describe the use of three-dimensional ultrashort echo time (3D UTE) sequences with TEs down to 8 μs for imaging of these species. Image contrast was gener...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2010.11.003
更新日期：2011-05-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
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更新日期：2020-01-01 00:00:00
abstract：:Diffraction ideas were first introduced to NMR by Mansfield and Grannell. Here we compare "Mansfield (k-space) diffraction" with the "diffusive (q-space) diffraction," noting their similarities and differences. The diffusive-diffraction concept is extremely helpful in elucidating the Pulsed Gradient Spin Echo NMR expe...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(96)00152-x
更新日期：1996-01-01 00:00:00
abstract：PURPOSE:In this study we proposed a fully automated method for localizing and segmenting the ascending aortic lumen with phase-contrast magnetic resonance imaging (PC-MRI). MATERIAL AND METHODS:Twenty-five phase-contrast series were randomly selected out of a large population dataset of patients whose cardiac MRI exam...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2017.11.010
更新日期：2018-04-01 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
abstract：PURPOSE:This study aimed to establish the topographical and zonal T2 patterns of multi-resolution MRI in medial tibial cartilage in a canine model of osteoarthritis (OA), initiated by the anterior cruciate ligament (ACL) transection surgery, and studied after 8-weeks and 12-weeks post-surgery. METHODS:Articular cartil...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2021.01.002
更新日期：2021-01-22 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(90)90242-t
更新日期：1990-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2005.10.013
更新日期：2006-02-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)92460-0
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(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/s0730-725x(01)00403-9
更新日期：2001-07-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(92)90411-r
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/s0730-725x(98)00130-1
更新日期：1998-11-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2014.07.010
更新日期：2014-11-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2013.02.008
更新日期：2013-07-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00008-3
更新日期：1998-09-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2004.01.057
更新日期：2004-09-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(03)00127-9
更新日期：2003-04-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2005.12.031
更新日期：2006-05-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2020.04.013
更新日期：2020-07-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2017.12.029
更新日期：2018-05-01 00:00:00
abstract：:Etched particle tracks produced after heavy ion irradiation of polymer foils are used as model systems to test the performance of NMR in a newly developed ultrahigh magnetic field gradient system. The stimulated NMR echo decay of molecules diffusing in the channels, formulated in terms of the self part of the intermed...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)91527-x
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：10.1016/0730-725x(92)90481-e
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/j.mri.2004.01.007
更新日期：2004-04-01 00:00:00
abstract：INTRODUCTION:Recent animal and human epidemiological studies suggest that early childhood exposure to anesthesia may have adverse effects on brain development. As more than 50% of pregnant women in the United States and one-third in the United Kingdom receive regional anesthesia during labor and delivery, understanding...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2014.08.033
更新日期：2015-02-01 00:00:00
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pub_type： 杂志文章
doi：10.1016/s0730-725x(00)00199-5
更新日期：2000-11-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2009.12.004
更新日期：2010-04-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(02)00639-2
更新日期：2003-02-01 00:00:00
