Dataset Information

In Vivo ¹ H MR Spectroscopy of Biliary Components of Human Gallbladder at 7T.

ABSTRACT:

Background

Previous in vivo proton MR spectroscopy (MRS) studies have demonstrated the possibility of quantifying amide groups of conjugated bile acids (NHCBA), olefinic lipids and cholesterol (OLC), choline-containing phospholipids (CCPLs), taurine and glycine conjugated bile acids (TCBA, GCBA), methylene group of lipids (ML), and methyl groups of bile acids, lipids, and cholesterol (BALC1.0, BALC0.9, and TBAC) in the gallbladder, which may be useful for the study of cholestatic diseases and cholangiopathies. However, these studies were performed at 1.5T and 3T, and higher magnetic fields may offer improved spectral resolution and signal intensity.

Purpose

To develop a method for gallbladder MRS at 7T.

Study type

Retrospective, technical development.

Population

Ten healthy subjects (five males and five females), two patients with primary biliary cholangitis (PBC) (one male and one female), and one patient with primary sclerosing cholangitis (PSC) (female).

Field strength/sequence

Free-breathing single-voxel MRS with a modified stimulated echo acquisition mode (STEAM) sequence at 7T.

Assessment

Postprocessing was based on the T₂ relaxation of water in the gallbladder and in the liver. Concentrations of biliary components were calculated using water signal. All data were corrected for T₂ relaxation times measured in healthy subjects.

Statistical tests

The range of T₂ relaxation time and concentration per bile component, and the resulting mean and standard deviation, were calculated.

Results

The concentrations of gallbladder components in healthy subjects were: NHCBA: 93?±?66?mM, OLC: 154?±?124?mM, CCPL: 42?±?17?mM, TCBA: 48?±?35?mM, GCBA: 67?±?32?mM, ML: 740?±?391?mM, BALC1.0: 175?±?92?mM, BALC0.9: 260?±?138?mM, and TBAC: 153?±?90?mM. Mean concentrations of all bile components were found to be lower in patients.

Data conclusion

This work provides a protocol for designing future MRS investigations of the bile system in vivo.

Evidence level

2 TECHNICAL EFFICACY STAGE: 1.

SUBMITTER: Gajdosik M

PROVIDER: S-EPMC7754442 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Publications

In Vivo <sup>1</sup> H MR Spectroscopy of Biliary Components of Human Gallbladder at 7T.

Gajdošík Martin M Chmelík Marek M Halilbasic Emina E Pfleger Lorenz L Klepochová Radka R Trauner Michael M Trattnig Siegfried S Krššák Martin M

Journal of magnetic resonance imaging : JMRI 20200605 1

<h4>Background</h4>Previous in vivo proton MR spectroscopy (MRS) studies have demonstrated the possibility of quantifying amide groups of conjugated bile acids (NHCBA), olefinic lipids and cholesterol (OLC), choline-containing phospholipids (CCPLs), taurine and glycine conjugated bile acids (TCBA, GCBA), methylene group of lipids (ML), and methyl groups of bile acids, lipids, and cholesterol (BALC1.0, BALC0.9, and TBAC) in the gallbladder, which may be useful for the study of cholestatic disease ...[more]

PMID: 32501627

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Dataset Information

In Vivo ¹ H MR Spectroscopy of Biliary Components of Human Gallbladder at 7T.

Background

Purpose

Study type

Population

Field strength/sequence

Assessment

Statistical tests

Results

Data conclusion

Evidence level

Publications

In Vivo <sup>1</sup> H MR Spectroscopy of Biliary Components of Human Gallbladder at 7T.

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Dataset Information

In Vivo 1 H MR Spectroscopy of Biliary Components of Human Gallbladder at 7T.

Background

Purpose

Study type

Population

Field strength/sequence

Assessment

Statistical tests

Results

Data conclusion

Evidence level

Publications

In Vivo <sup>1</sup> H MR Spectroscopy of Biliary Components of Human Gallbladder at 7T.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

In Vivo ¹ H MR Spectroscopy of Biliary Components of Human Gallbladder at 7T.