Abstract:
:Multi-echo pulse sequences for producing T2-weighted images in much reduced imaging times have recently been developed for routine clinical use. A number of recent articles have described the contrast obtained with fast spin-echo (FSE) sequences and have generally indicated that they depict tissues very similarly to conventional spin-echo (SE) imaging. There are, however, some important differences in contrast between some tissues in FSE images. This work presents a detailed study of the contrast obtained with FSE imaging sequences and examines the image sequence and tissue parameters which influence contrast. The use of multiple refocusing pulses produces several subtle effects not seen in conventional SE imaging sequences, and in this study the precise nature and extent of such effects are described. The relative contributions to image contrast of magnetization transfer, the decoupling of J-modulation effects, the production of stimulated echoes and direct saturation effects, of diffusion and of the effects of the differential attenuation of different spatial frequencies, are each quantified. The mechanisms responsible for the brighter fat signal seen in FSE images, as well as the loss of signal from some other tissues, are explained. Computer simulations, phantom experiments, and clinical images are all used to support the conclusions.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Constable RT,Anderson AW,Zhong J,Gore JCdoi
10.1016/0730-725x(92)90001-gsubject
Has Abstractpub_date
1992-01-01 00:00:00pages
497-511issue
4eissn
0730-725Xissn
1873-5894pii
0730-725X(92)90001-Gjournal_volume
10pub_type
杂志文章,评审abstract::The biodistribution and relative molar effectiveness of the ionic (GdCl3) and chelated (Gd-DTPA) forms of gadolinium (Gd) to enhance proton relaxation rates in rat kidney, liver and spleen were evaluated. Rats were given intravenous injections of either GdCl3 (100 mumol/kg) or Gd-DTPA (178 mumol/kg). Gd-DTPA was prima...
journal_title:Magnetic resonance imaging
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doi:10.1016/0730-725x(87)90023-3
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
doi:10.1016/0730-725x(95)02036-s
更新日期:1995-01-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(96)00094-x
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/s0730-725x(99)00074-0
更新日期:1999-11-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2014.08.025
更新日期:2014-12-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2013.06.006
更新日期:2013-11-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
doi:10.1016/j.mri.2016.08.016
更新日期:2016-12-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(03)00075-4
更新日期:2003-06-01 00:00:00
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journal_title:Magnetic resonance imaging
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doi:10.1016/j.mri.2013.06.009
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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journal_title:Magnetic resonance imaging
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更新日期:2000-06-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(93)90476-t
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(88)90409-2
更新日期:1988-05-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2005.10.006
更新日期:2006-02-01 00:00:00
abstract:PURPOSE:This study was done to test a series of MR sequences for evaluating the sciatic nerve after total hip arthroplasty (THA). MATERIAL AND METHODS:The study protocol was approved by the institutional review board. Informed consent was obtained from all patients. Twenty-five patients (11 men and 14 women mean age: ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2010.06.009
更新日期:2010-11-01 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:2019-06-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.10.023
更新日期:2013-05-01 00:00:00
abstract:PURPOSE:To evaluate the correlation between the pancreatic exocrine insufficiency estimated by cine-dynamic MRCP using spatially selective IR pulse and the severity stages (modified Cambridge classification) based on morphological changes of the pancreatic duct in patients with suspected chronic pancreatitis. MATERIAL...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2017.12.007
更新日期:2018-05-01 00:00:00
abstract:PURPOSE:To evaluate the reproducibility of quantitative diffusion measurements obtained with reduced Field of View (rFOV) and Multi-shot EPI (msEPI) acquisitions, using single-shot EPI (ssEPI) as a reference. METHODS:Diffusion phantom experiments, and prostate diffusion-weighted imaging in healthy volunteers and patie...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.04.006
更新日期:2018-09-01 00:00:00