Liver Imaging at 3.0 T: Diffusion-induced Black-Blood Echo-planar Imaging with Large Anatomic Volumetric Coverage as an Alternative for Specific Absorption Rate–intensive Echo-Train Spin-Echo Sequences: Feasibility Study

Published Online:Jul 1 2008https://doi.org/10.1148/radiol.2481070034

Abstract

Institutional Review Board approval and signed informed consent were obtained by all participants for an ongoing sequence optimization project at 3.0 T. The purpose of this study was to evaluate breath-hold diffusion-induced black-blood echo-planar imaging (BBEPI) as a potential alternative for specific absorption rate (SAR)-intensive spin-echo sequences, in particular, the fast spin-echo (FSE) sequences, at 3.0 T. Fourteen healthy volunteers (seven men, seven women; mean age ± standard deviation, 32.7 years ± 6.8) were imaged for this purpose. Liver coverage (20 cm, z-axis) was always performed in one 25-second breath hold. Imaging parameters were varied interactively with regard to echo time, diffusion b value, and voxel size. Images were evaluated and compared with fat-suppressed T2-weighted FSE images for image quality, liver delineation, geometric distortions, fat suppression, suppression of the blood signal, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR). An optimized short- (25 msec) and long-echo (80 msec) BBEPI provided full anatomic, single breath-hold liver coverage (100 and 50 sections, respectively), with resulting voxel sizes of 3.3 × 2.7 × 2.0 mm and 3.3 × 2.7 × 4.0 mm, respectively. Repetition time was 6300 msec, matrix size was 160 × 192, and an acceleration factor of 2.00 was used. b Values of more than 20 sec/mm² showed better suppression of the blood signal but b values of 10 sec/mm² provided improved volume coverage and signal consistency. Compared with fat-suppressed T2-weighted FSE, the optimized BBEPI sequence provided (a) comparable image quality and liver delineation, (b) acceptable geometric distortions, (c) improved suppression of fat and blood signals, and (d) high CNR and SNR. BBEPI is feasible for fast, low-SAR, thin-section morphologic imaging of the entire liver in a single breath hold at 3.0 T.

References

1 Glockner JF. Hepatobiliary MRI: current concepts and controversies. J Magn Reson Imaging 2007; 25: 681–695.
Medline Google Scholar
2 Kondo H, Kanematsu M, Itoh K, et al. Does T2-weighted MR imaging improve preoperative detection of malignant hepatic tumors? observer performance study in 49 surgically proven cases. Magn Reson Imaging 2005;23:89–95.
Medline Google Scholar
3 Martin DR, Friel HT, Danrad R, De Becker J, Hussain SM. Approach to abdominal imaging at 1.5 Tesla and optimization at 3 Tesla. Magn Reson Imaging Clin N Am 2005;13:241–254.
Medline Google Scholar
4 Merkle EM, Dale BM, Paulson EK. Abdominal MR imaging at 3T. Magn Reson Imaging Clin N Am 2006;14:17–26.
Medline Google Scholar
5 O'Regan DP, Fitzgerald J, Allsop J, et al. A comparison of MR cholangiopancreatography at 1.5 and 3.0 Tesla. Br J Radiol 2005;78:894–898.
Medline Google Scholar
6 Edelman RR, Salanitri G, Brand R, et al. Magnetic resonance imaging of the pancreas at 3.0 tesla: qualitative and quantitative comparison with 1.5 tesla. Invest Radiol 2006;41:175–180.
Medline Google Scholar
7 von Falkenhausen MM, Lutterbey G, Morakkabati-Spitz N, et al. High-field-strength MR imaging of the liver at 3.0 T: intraindividual comparative study with MR imaging at 1.5 T. Radiology 2006;241:156–166.
Google Scholar
8 Hussain SM, Wielopolski PA, Martin DR. Abdominal magnetic resonance imaging at 3.0 T: problem or a promise for the future? Top Magn Reson Imaging 2005;16:325–335.
Medline Google Scholar
9 Schindera ST, Merkle EM, Dale BM, Delong DM, Nelson RC. Abdominal magnetic resonance imaging at 3.0 T: what is the ultimate gain in signal-to-noise ratio? Acad Radiol 2006;13:1236–1243.
Medline Google Scholar
10 de Bazelaire CM, Duhamel GD, Rofsky NM, Alsop DC. MR imaging relaxation times of abdominal and pelvic tissues measured in vivo at 3.0 T: preliminary results. Radiology 2004;230:652–659.
Google Scholar
11 Stanisz GJ, Odrobina EE, Pun J, et al. T1, T2 relaxation and magnetization transfer in tissue at 3T. Magn Reson Med 2005;54:507–512.
Medline Google Scholar
12 Michaely HJ, Kramer H, Dietrich O, et al. Intraindividual comparison of high-spatial-resolution abdominal MR angiography at 1.5 T and 3.0 T: initial experience. Radiology 2007;244:907–913.
Google Scholar
13 Schick F. Whole-body MRI at high field: technical limits and clinical potential. Eur Radiol 2005;15:946–959.
Medline Google Scholar
14 Muller MF, Edelman RR. Echo planar imaging of the abdomen. Top Magn Reson Imaging 1995;7:112–119.
Medline Google Scholar
15 Hussain SM, De Becker J, Hop WC, Dwarkasing S, Wielopolski PA. Can a single-shot black-blood T2-weighted spin-echo echo-planar imaging sequence with sensitivity encoding replace the respiratory-triggered turbo spin-echo sequence for the liver? an optimization and feasibility study. J Magn Reson Imaging 2005;21:219–229.
Medline Google Scholar
16 Taouli B, Vilgrain V, Dumont E, Daire JL, Fan B, Menu Y. Evaluation of liver diffusion isotropy and characterization of focal hepatic lesions with two single-shot echo-planar MR imaging sequences: prospective study in 66 patients. Radiology 2003;226:71–78.
Google Scholar
17 Wielopolski PA, Schmitt F, Stehling MK. Echo-planar imaging pulse sequences. In: Schmitt F, Stehling MK, Turner R, eds. Echo-planar imaging: theory, technique and application. Berlin, Germany: Springer-Verlag, 1998; 65–141.
Google Scholar
18 Namimoto T, Yamashita Y, Sumi S, Tang Y, Takahashi M. Focal liver masses: characterization with diffusion-weighted echo-planar MR imaging. Radiology 1997;204:739–744.
Google Scholar
19 Okada Y, Ohtomo K, Kiryu S, Sasaki Y. Breath-hold T2-weighted MRI of hepatic tumors: value of echo planar imaging with diffusion-sensitizing gradient. J Comput Assist Tomogr 1998;22:364–371.
Medline Google Scholar

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Published in print: 2008

Vol. 248, No. 1

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