Premium
Differentiating hepatic abscess from malignant mimickers: Value of diffusion‐weighted imaging with an emphasis on the periphery of the lesion
Author(s) -
Park Hyun Jeong,
Kim Seong Hyun,
Jang Kyung Mi,
Lee Soon Jin,
Park Min Jung,
Choi Dongil
Publication year - 2013
Publication title -
journal of magnetic resonance imaging
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.563
H-Index - 160
eISSN - 1522-2586
pISSN - 1053-1807
DOI - 10.1002/jmri.24112
Subject(s) - medicine , receiver operating characteristic , effective diffusion coefficient , abscess , diffusion mri , hepatic abscess , radiology , liver abscess , lesion , magnetic resonance imaging , nuclear medicine , pathology , surgery
Purpose To evaluate the efficacy of diffusion‐weighted imaging (DWI) in differentiating hepatic abscess from malignant mimickers with an emphasis on periphery of the lesions. Materials and Methods Thirty‐nine patients with hepatic abscess and 74 patients with malignant hepatic tumors were included, who underwent gadoxetic acid‐enhanced MRI. For qualitative and quantitative analysis, signal intensities and apparent diffusion coefficient (ADC) values of the periphery were assessed. Two observers reviewed DWI and ADC maps rated using a 5‐point scale. Diagnostic performance was evaluated using the receiver operating characteristics (ROC) curve analysis. Results The periphery of hepatic abscesses was T1‐hypointense, arterial hyperintense, and hypointense on hepatobiliary phase less frequently than that of malignant tumors ( P < 0.05). No hepatic abscesses showed peripheral washout on 3‐min late phase compared with malignant tumors (59.5%) ( P < 0.001). Both groups showed hyperintense rims on DWI, but, 37(94.9%) abscesses revealed rims with high ADC values compared with one (1.4%) malignant tumor ( P < 0.001). Mean ADC values of abscesses (1.47 × 10 −3 mm 2 /s ± 0.36 [standard deviation]) were significantly higher than those of malignancies (0.68 × 10 −3 mm 2 /s ± 0.20). Diagnostic performance (area under the ROC curve [ Az ]) of DWI in identifying hepatic abscess was 0.986 and 0.982 for each observer. Conclusion In addition to conventional MRI, DWI is helpful in differentiating hepatic abscess from malignant mimickers. J. Magn. Reson. Imaging 2013;38:1333–1341. © 2013 Wiley Periodicals, Inc.