Abstract：
:T1 and T2 relaxation times are fundamental parameters for signal contrast behaviour in MRI. A number of ex vivo relaxometry studies have dealt with the magnetic field dispersion of T1. By means of multicenter study within the frame of the COMAC BME Concerted Action on Tissue Characterization by MRI and MRS, the in vivo field dispersion of T1 and T2 has been measured in order to evaluate whether ex vivo data are representative for the in vivo situation. Brain, skeletal muscle, and liver of healthy human volunteers were studied. Fifteen MR units with a field strength ranging from 0.08 T to 1.5 T took part in the trial, which comprised 218 volunteers. All the MR systems were tested for measurement accuracy using the Eurospin TO5 test object. The measured relaxation data were subsequently corrected according to the obtained calibration curves. The results showed a clear field dispersion of T1, whereas no significant variations were seen for T2. Our in vivo data were generally in reasonable agreement with proposed models based on ex vivo measurements.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Henriksen O,de Certaines JD,Spisni A,Cortsen M,Muller RN,Ring PBdoi
10.1016/0730-725x(93)90202-osubject
Has Abstractpub_date
1993-01-01 00:00:00pages
851-6issue
6eissn
0730-725Xissn
1873-5894pii
0730-725X(93)90202-Ojournal_volume
11pub_type
杂志文章,多中心研究abstract：PURPOSE:The purpose of this study was to assess relationships between intramuscular adipose tissue (IntraMAT) content determined by MRI and intramyocellular lipids (IMCL) and extramyocellular lipids (EMCL) determined by (1)H magnetic resonance spectroscopy ((1)H MRS) or echo intensity determined by B-mode ultrasonograp...
journal_title：Magnetic resonance imaging
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更新日期：2004-04-01 00:00:00
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更新日期：2010-01-01 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：1993-01-01 00:00:00
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更新日期：2012-01-01 00:00:00
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