Original Research — Gastrointestinal Imaging
Characterization of adrenal lesions using chemical shift MRI: Comparison between 1.5 tesla and two echo time pair selection at 3.0 tesla MRI
Article first published online: 14 OCT 2011
Copyright © 2011 Wiley Periodicals, Inc.
Journal of Magnetic Resonance Imaging
Volume 35, Issue 1, pages 95–102, January 2012
How to Cite
Nakamura, S., Namimoto, T., Morita, K., Utsunomiya, D., Oda, S., Nakaura, T., Hirai, T. and Yamashita, Y. (2012), Characterization of adrenal lesions using chemical shift MRI: Comparison between 1.5 tesla and two echo time pair selection at 3.0 tesla MRI. J. Magn. Reson. Imaging, 35: 95–102. doi: 10.1002/jmri.22728
- Issue published online: 15 DEC 2011
- Article first published online: 14 OCT 2011
- Manuscript Accepted: 30 JUN 2011
- Manuscript Received: 20 JAN 2011
- chemical shift imaging;
- gradient echo
To compare chemical shift MRI obtained at 1.5 Tesla (T) and two pairs of echo time (TE) in-phase and opposed-phase 3.0T MRI to assess their usefulness for the differentiation between adrenal adenomas and non-adenomas.
Materials and Methods:
We evaluated 91 adrenal masses (75 adenomas, 16 non-adenomas) in 85 patients. The MR imaging parameters were: T1-dual-gradient-echo(GRE) [echo times (TEs) = 1.1/2.3 ms (first-echo-pair) or 3.5/4.6 ms (second-echo-pair)] at 3.0T, and T1-dual-GRE (TEs = 2.4/4.8 ms) at 1.5T. Scans were quantitatively assessed for the signal intensity (SI) index, calculated as [(SIin-phase-SIopposed-phase)/(SIin-phase)] × 100(%). To test for differences between adenomas and non-adenomas, we performed quantitative analysis and analysis of variance.
For all images, the SI index differed significantly between adenomas and non-adenomas. The sensitivity /specificity of SI index at the first-echo-pair of 3.0T was 100%/ 100%, that of 95.6%/ 100% at the second-echo-pair of 3.0T, and 91.7%/ 88.9% at 1.5T, respectively. At intra-individual comparisons, the SI indices obtained with the second-echo-pair at 3.0T were significantly lower than on the first-echo-pair at 3.0T and 1.5T.
Chemical shift MRI at 3.0T provides more accurate differentiation between adenomas and non-adenomas than at 1.5T. The SI index of the first-echo-pair at 3.0T is the most reliable evaluation method for differentiating adrenal adenomas from non-adenomas. J. Magn. Reson. Imaging 2012;35:95-102. © 2011 Wiley Periodicals, Inc.