Suraj Serai PhD, Abstract Co-Author: Nothing to Disclose

Hui Wang, Abstract Co-Author: Employee, Koninklijke Philips NV

Meng Yin, Abstract Co-Author: Nothing to Disclose

Richard L. Ehman MD, Abstract Co-Author: CEO, Resoundant, Inc

Daniel Jay Podberesky MD, Presenter: Author with royalties, Amirsys, Inc Speakers Bureau, Toshiba Corporation Travel support, General Electric Company Travel support, Koninklijke Philips NV Travel support, Siemens AG Consultant, Guerbet SA

To our knowledge, a direct comparison between MR Elastography (MRE) derived liver stiffness on the same subject performed back-to-back between two different vendor platforms has not been reported. The purpose of this study was to evaluate and validate reproducibility of MRE on two vendor platforms.

8 healthy volunteers with no prior history of liver disease and 3 clinical patients with chronic liver disease were recruited for the study. MRE exams were performed twice on two different 1.5T MR scanners – once on a Philips MR scanner (Ingenia, Philips Healthcare) and immediately afterward on a GE MR scanner (HDx, GE Healthcare). All scan parameters were kept identical on the two platforms to the best extent possible. After the MRE magnitude and phase images were obtained, the data was converted into quantitative images displaying the stiffness of the liver parenchyma. Liver stiffness values between the two platforms were compared using interclass correlation with a p value < 0.05 considered statistically significant. 

Mean liver stiffness values for the 8 volunteers ranged from 1.96 – 2.65 kPa on the GE platform, and from 1.90 -2.46 kPa on the Philips platform. Mean liver stiffness values for the 3 clinical patients ranged from 2.1 –4.04 kPa on the GE platform, and from 2.08-4.05 kPa on the Philips platform. Liver stiffness differences ranged from 0.04 – 0.23 (1.8% – 9.6%) for the volunteer subjects and from 0.01 – 0.36 (0.25% - 9.6%) for the clinical patients. Interclass correlation coefficient, r=0.98 with 95% confidence interval obtained as 0.8264-0.9974 implying high correlation. The p-value for this coefficient is 0.005, which is significant. Figure shows a set of magnitude images, wave images and stiffness maps in the same subject.

As MRE becomes more widespread in its usage, and as more vendor platforms become approved by the FDA, it is imperative that cross vendor validation studies be performed to ensure that liver stiffness values are consistent across different platforms. In this study, we have demonstrated that on two specific vendor platforms, there was no statistically significant difference in MRE derived liver stiffness on the same subject. 

MRE is a promising non-invasive quantitative imaging tool to determine liver stiffness in the assessment of patients with chronic liver disease, and in this study shows excellent consistency across two vendor platforms. 

Serai, S, Wang, H, Yin, M, Ehman, R, Podberesky, D, Cross-vendor Validation of Liver MR Elastography.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14001303.html