Evaluation of a single-breath-hold radial turbo-spin-echo sequence for T2 mapping of the liver at 3T

Diana Bencikova; Fei Han; Stephan Kannengieser; Marcus Raudner; Sarah Poetter-Lang; Nina Bastati; Gert Reiter; Raphael Ambros; Ahmed Ba-Ssalamah; Siegfried Trattnig; Martin Krššák

doi:10.1007/s00330-021-08439-y

Evaluation of a single-breath-hold radial turbo-spin-echo sequence for T2 mapping of the liver at 3T

Eur Radiol. 2022 May;32(5):3388-3397. doi: 10.1007/s00330-021-08439-y. Epub 2021 Dec 23.

Authors

Diana Bencikova^{1

2}, Fei Han³, Stephan Kannengieser⁴, Marcus Raudner¹, Sarah Poetter-Lang¹, Nina Bastati¹, Gert Reiter⁵, Raphael Ambros¹, Ahmed Ba-Ssalamah¹, Siegfried Trattnig^{1

2

6}, Martin Krššák^{7

8}

Affiliations

¹ Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
² Christian Doppler Laboratory for Clinical Molecular Imaging, MOLIMA, MUW, Vienna, Austria.
³ Siemens Medical Solutions, Los Angeles, CA, USA.
⁴ MR Application Predevelopment, Siemens Healthcare GmbH, Erlangen, Germany.
⁵ Research and Development, Siemens Healthcare Diagnostics GmbH, Graz, Austria.
⁶ Institute for Clinical Molecular MRI in the Musculoskeletal System, Karl Landsteiner Society, Vienna, Austria.
⁷ Christian Doppler Laboratory for Clinical Molecular Imaging, MOLIMA, MUW, Vienna, Austria. martin.krssak@meduniwien.ac.at.
⁸ Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Währinger Gürtel 18-20, A-1090, Vienna, Austria. martin.krssak@meduniwien.ac.at.

Abstract

Objectives: T2 mapping of the liver is a potential diagnostic tool, but conventional techniques are difficult to perform in clinical practice due to long scan time. We aimed to evaluate the accuracy of a prototype radial turbo-spin-echo (rTSE) sequence, optimized for multi-slice T2 mapping in the abdomen during one breath-hold at 3 T.

Methods: A multi-sample (fat: 0-35%) agarose phantom doped with MnCl₂ and 80 subjects (73 patients undergoing abdomen MR examination and 7 healthy volunteers) were investigated. A radial turbo-spin-echo (rTSE) sequence with and without fat suppression, a Cartesian turbo-spin-echo (Cart-TSE) sequence, and a single-voxel multi-echo STEAM spectroscopy (HISTO) were performed in phantom, and fat-suppressed rTSE and HISTO sequences were performed in in vivo measurements. Two approaches were used to sample T2 values: manually selected circular ROIs and whole liver analysis with Gaussian mixture models (GMM).

Results: The rTSE-T2s values exhibited a strong correlation with Cart-TSE-T2s (R² = 0.988) and with HISTO-T2s of water (R² = 0.972) in phantom with an offset between rTSE and Cart-TSE maps (mean difference = 3.17 ± 1.18 ms). The application of fat suppression decreased T2 values, and the effect was directly proportional to the amount of fat. Measurements in patients yielded a linear relationship between rTSE- and HISTO-T2s (R² = 0.546 and R² = 0.580 for ROI and GMM, respectively).

Conclusion: The fat-suppressed rTSE sequence allows for fast and accurate determination of T2 values of the liver, and appears to be suitable for further large cohort studies.

Key points: •Radial turbo-spin-echo T2 mapping performs comparably to Cartesian TSE-T2 mapping, but an offset in values is observed in phantom measurements. •Fat-suppressed radial turbo-spin-echo T2 mapping is consistent with T2 of water as assessed by MRS in phantom measurements. •Fat-suppressed radial turbo-spin-echo sequence allows fast T2 mapping of the liver in a single breath-hold and is correlated with MRS-based T2 of water.

Keywords: Abdomen; Breath holding; Liver; Magnetic resonance imaging; Quantitative evaluation.

MeSH terms

Abdomen
Breath Holding*
Humans
Liver / diagnostic imaging
Magnetic Resonance Imaging* / methods
Water

Substances

Water