Abstract：
:The NMR relaxivities of Gd-EOB-DTPA and Gd-DTPA were determined in the kidney and liver of intact male Wistar rats immediately following sacrifice and in vitro in solutions and gels, at 1.5 T using a clinical MR scanner, T1 and T2 values of tissue samples were derived from spin-echo image sequences. Tissue gadolinium concentrations were determined by radioassay of Gd153, Gd-EOB-DTPA T1 and T2 relaxivities, R1 and R2 (s-1 mmole-1 kg), were found to be 10.7 +/- 0.5 and 22.5 +/- 3.2 respectively, for liver, 2.4 +/- 0.2 and 12.1 +/- 1.7 for kidney cortex, 2.7 +/- 0.2 and 14.5 +/- 1.9 for kidney outer medulla, 2.0 +/- 0.2 and 11.4 +/- 2.1 for kidney inner medulla. Gd-DTPA R1 and R2 were found to be 4.8 +/- 0.4 and 14.5 +/- 3.7 for liver, 1.2 +/- 0.1 and 7.9 +/- 0.8 for kidney cortex, 1.6 +/- 0.1 and 10.2 +/- 1.4 for kidney outer medulla, 1.3 +/- 0.1 and 10.2 +/- 1.2 for kidney inner medulla. Gd-EOB-DTPA and Gd-DTPA R1 was increased in liver compared to agarose gets at 38 degrees C (4.49 +/- 0.03 and 3.47 +/- 0.06), but reduced in kidney tissues. All R2 were elevated compared to agarose gels at 38 degrees C (5.72 +/- 0.12 and 4.12 +/- 0.03). Elevated R2 and R1 (expressed in terms of the concentration of gadolinium per kg of tissue) can be accounted for in part by the lower water content of tissues compared with gels or solutions increased microviscosity and binding to macromolecules. In addition, susceptibility effects may give rise to further increases in R2. By contrast, the reduced R1 observed in kidney may be the result of compartmentalization of the magnetopharmaceuticals. Statistically improved fits were obtained for T1 recovery curves for liver in the presence of Gd-EOB-DTPA when a dual exponential model was used. Assuming in vitro values for the relaxivities of these artificial contrast agents will lead to inaccuracies when relating observed signal enhancement factors to tissue gadolinium concentration.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Shuter B,Tofts PS,Wang SC,Pope JMdoi
10.1016/0730-725x(95)02097-dsubject
Has Abstractpub_date
1996-01-01 00:00:00pages
243-53issue
3eissn
0730-725Xissn
1873-5894pii
0730-725X(95)02097-Djournal_volume
14pub_type
杂志文章abstract：PURPOSE:The state-of-the-art method to quantify sodium concentrations in vivo consists in a fully relaxed 3D spin-density (SD) weighted acquisition. Nevertheless, most sodium MRI clinical studies use short-TR SD acquisitions to reduce acquisition durations. We present a clinically viable implementation of the Variable ...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2019.01.015
更新日期：2019-05-01 00:00:00
abstract：:Functional magnetic resonance imaging (fMRI) has found widespread clinical interest. Difficulties in clinical use of the fMRI technique arise, considering the lack of knowledge about activation task performance. This accounts especially for sensorimotor activation studies, in which performance of the sensorimotor acti...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(95)02052-u
更新日期：1996-01-01 00:00:00
abstract：PURPOSE:To develop a method for estimating metabolite concentrations using phased-array coils and sensitivity-encoded (SENSE) magnetic resonance spectroscopic images (MRSI) of the human brain. MATERIALS AND METHODS:The method is based on the phantom replacement technique and uses receive coil sensitivity maps and body...
journal_title：Magnetic resonance imaging
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doi：10.1016/j.mri.2009.11.003
更新日期：2010-04-01 00:00:00
abstract：OBJECTIVE:To characterize capillary perfusion and tissue diffusion changes in transplant renal artery stenosis (TRAS) with diffusion-weighted imaging (DWI). MATERIALS & METHODS:We retrospectively identified 30 patients with non-contrast enhanced magnetic resonance angiography-proven TRAS. Another 20 kidney transplant ...
journal_title：Magnetic resonance imaging
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doi：10.1016/j.mri.2019.05.007
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journal_title：Magnetic resonance imaging
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doi：10.1016/j.mri.2017.11.010
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00081-2
更新日期：1998-09-01 00:00:00
abstract：:Using both quantitative computer-assisted analysis and visual estimation the MR imaging response of brain metastases to whole-brain radiotherapy (WBRT) was prospectively studied in 49 patients. Compared to the computer-assisted analysis, the precision of the visual estimation (by two readers in conference) of tumor re...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(96)00024-0
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/j.mri.2005.11.001
更新日期：2006-06-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(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
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更新日期：2001-12-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2014.04.003
更新日期：2014-09-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2020.06.020
更新日期：2020-10-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2004.01.013
更新日期：2004-05-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(02)00608-2
更新日期：2002-12-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2012.11.001
更新日期：2013-06-01 00:00:00
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journal_title：Magnetic resonance imaging
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doi：10.1016/j.mri.2006.07.012
更新日期：2006-12-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00208-2
更新日期：1999-05-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2007.02.002
更新日期：2007-11-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)91234-n
更新日期：1994-01-01 00:00:00
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journal_title：Magnetic resonance imaging
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doi：10.1016/0730-725x(93)90214-x
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(94)00076-f
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/j.mri.2018.10.002
更新日期：2019-02-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00176-3
更新日期：1999-04-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(91)90540-3
更新日期：1991-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(00)00134-x
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/s0730-725x(03)00201-7
更新日期：2003-11-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.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/s0730-725x(00)00229-0
更新日期：2001-01-01 00:00:00
