Nonhypervascular Hypointense Nodules at Gadoxetic Acid-enhanced MR Imaging in Chronic Liver Disease: Diffusion-weighted Imaging for Characterization.
OBJECTIVE
To compare the diagnostic performance of magnetic resonance (MR) imaging features, including those on diffusion-weighted (DW) and T2-weighted images, in differentiating between hypovascular hepatocellular carcinoma (HCC) and dysplastic nodules seen as hypointense nodules at hepatobiliary phase gadoxetic acid-enhanced MR imaging.


METHODS
The institutional review board approved this retrospective study and waived the need to obtain informed patient consent. There were 53 patients (39 men and 14 women; age range, 32-75 years) with histologically proven hypovascular HCCs (n = 25) and/or dysplastic nodules (n = 31) who underwent gadoxetic acid-enhanced MR imaging at 3.0-T between March 2011 and January 2014. Images of 25 HCCs and 31 dysplastic nodules were analyzed for nodule size; signal intensity on T1- and T2-weighted, portal venous phase, and DW (b value = 800 sec/mm(2)) images; and intralesional fat. Correlations between the hyperintensity grade of lesions and the liver-to-lesion signal intensity ratio at T2-weighted and DW imaging were determined by means of analysis with generalized estimating equations.


RESULTS
Hyperintensity at T2-weighted and DW imaging and hypointensity in the portal venous phase were significant features for differentiating hypovascular HCCs from dysplastic nodules (P < .05). The sensitivity of DW imaging tended to be higher than that of T2-weighted imaging (72.0% [18 of 25] vs 40.0% [10 of 25]; P = .008 for grade 2 and 3 hyperintensity). Use of the parameter of hyperintensity similar to or slightly lower than the signal intensity of the spleen on DW images (b value = 800 sec/mm(2)) yielded a specificity of 100% (31 of 31) for the diagnosis of hypovascular HCC by differentiating it from a dysplastic nodule.


CONCLUSIONS
Hyperintensity at DW imaging could be a useful MR imaging feature for differentiating hypovascular HCCs from dysplastic nodules seen as hypointense nodules at gadoxetic acid-enhanced MR imaging.
From the Department of Radiology, Soonchunhyang University Seoul Hospital, Seoul, Republic of Korea (J.H.); and Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Republic of Korea (Y.K.K., W.K.J., D.C., H.R., W.J.L.).
Jiyoung
J
Hwang
From the Department of Radiology, Soonchunhyang University Seoul Hospital, Seoul, Republic of Korea (J.H.); and Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Republic of Korea (Y.K.K., W.K.J., D.C., H.R., W.J.L.).
Young Kon
YK
Kim
From the Department of Radiology, Soonchunhyang University Seoul Hospital, Seoul, Republic of Korea (J.H.); and Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Republic of Korea (Y.K.K., W.K.J., D.C., H.R., W.J.L.).
Woo Kyoung
WK
Jeong
From the Department of Radiology, Soonchunhyang University Seoul Hospital, Seoul, Republic of Korea (J.H.); and Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Republic of Korea (Y.K.K., W.K.J., D.C., H.R., W.J.L.).
Dongil
D
Choi
From the Department of Radiology, Soonchunhyang University Seoul Hospital, Seoul, Republic of Korea (J.H.); and Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Republic of Korea (Y.K.K., W.K.J., D.C., H.R., W.J.L.).
Hyunchul
H
Rhim
From the Department of Radiology, Soonchunhyang University Seoul Hospital, Seoul, Republic of Korea (J.H.); and Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul 135-710, Republic of Korea (Y.K.K., W.K.J., D.C., H.R., W.J.L.).
Won Jae
WJ
Lee
D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis*; D002908:Chronic Disease; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008107:Liver Diseases / Q000175:diagnosis*; D008113:Liver Neoplasms / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
D003287:Contrast Media; C073590:gadolinium ethoxybenzyl DTPA; D019786:Gadolinium DTPA