Mi Hee Lee MD, Abstract Co-Author: Nothing to Disclose

Seong Hyun Kim, Abstract Co-Author: Nothing to Disclose

Hee Jung Kim, Abstract Co-Author: Nothing to Disclose

Won Jae Lee MD, Abstract Co-Author: Nothing to Disclose

Hye Na Jung MD, Presenter: Nothing to Disclose

Min Woo Lee, Abstract Co-Author: Nothing to Disclose

To evaluate the most useful findings of gadoxetic acid-enhanced MRI using 3.0T for differentiating focal eosinophilic infiltration (FEI) from metastasis in the liver.

A total of 25 patients with 39 FEIs and 51 patients with 79 metastases in the liver were included. All patients performed gadoxetic acid-enhanced MRI using 3T were reviewed retrospectively. All metastases and 6 FEIs were pathologically proven. The remaining 33 FEIs were diagnosed based on laboratory, follow-up imaging findings. MRI consisted of unenhanced T1- and T2WI, gadoxetic acid-enhanced 3D T1 GRE images(arterial, portal, 3-minute, 20-minute delayed hepatobiliary phase). Differences of size between T2WI and hepatobiliary phase for lesions(>1cm) in 2 groups were compared using Student-t test. Margin(ill vs. well), shape(non-spherical vs. spherical), signal intensity on T1WI(iso to high vs. low) and T2WI(iso to low vs. high), enhancement pattern(non-rim vs. rim)on dynamic images and presence or absence of target appearance on hepatobiliary phase were analyzed and compared using univariate and multivariate analyses

Mean differences of size between T2WI and hepatobiliary phase were 2.06 mm in FEIs and 0.71 mm in metastases, that was statically significant(P<0.001). In 39 FEIs, ill-defied(30, 76.9%), non-spherical(25, 64.1%), isointensity(25, 64.1%) on T1WI, hyperintensity(36, 92.3%) on T2WI, non-rim enhancement on dynamic image(31 in arterial, 33 in portal and 37 in 3-minute delayed phase), absence of target appearance on hepatobiliary phase(37, 95%) were common. In 79 metastases, well-defied(78, 98.7%), spherical(78, 98.7%), hypointensity(76, 96.2%) on T1WI, hyperintensity(77, 97.5%) on T2WI, rim enhancement on dynamic image (62 in arterial, 59 in portal and 41 in 3-minute delayed phase), presence of target appearance on hepatobiliary phase(46, 58.2%) were common. On univariate analysis, all MR features of FEIs except for hyperintensity on T2WI in comparison with those of metastases were significantly different (p< 0.0001). On multivariate analysis, ill defined(p<0.0155) and isointensity on T1WI (p<0.0028) were independent variables.

Changing size of FEIs, Ill-defined and isointensity on T1WI are the most useful features differentiating FEIs from Metastases in the liver on gadoxetic acid-enhanced 3T MRI

To help differentiating FEI from metastasis in the liver with gadoxetic acid-enhanced MRI

Lee, M, Kim, S, Kim, H, Lee, W, Jung, H, Lee, M, Differentiating Focal Eosinophilic Infiltration from Metastasis in the Liver with Gadoxetic Acid-enhanced MRI.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8015306.html