gadoxetic-acid-disodium and Liver-Abscess

To evaluate the role of diffusion-weighted magnetic resonance imaging (DW-MRI) in the differentiation of hepatic abscesses from non-infected fluid collections.. In this retrospective study, 22 hepatic abscesses and 27 non-infected hepatic fluid collections were examined in 27 patients who underwent abdominal MRI including DW-MRI. Two independent observers reviewed T2-weighted + DW-MRI and T2-weighted + contrast-enhanced T1-weighted (CET1W) images in two sessions. Detection rates and confidence levels were calculated and compared using McNemar's and Wilcoxon's signed rank tests, respectively. Apparent diffusion coefficient (ADC) values of abscesses and non-infected fluid collections were compared using the t-test. Receiver operating characteristic (ROC) curves were constructed.. There was no statistically significant difference in the accuracy of detecting abscesses using T2-weighted + DW-MRI (both observers: 21/22, 95.5%) versus T2-weighted + CET1W images (observer 1: 21/22, 95.5%; observer 2: 22/22, 100%; p < 0.01). Mean ADC values were significantly lower with abscesses versus non-infected fluid collections (0.83 ± 0.24 versus 2.25 ± 0.61 × 10(-3) mm(2)/s; p < 0.001). With ROC analysis there was good discrimination of abscess from non-infected fluid collections at a threshold ADC value of 1.36 × 10(-3) mm(2)/s.. DW-MRI allows qualitative and quantitative differentiation of abscesses from non-infected fluid collections in the liver.

Topics: Contrast Media; Diagnosis, Differential; Diffusion Magnetic Resonance Imaging; Exudates and Transudates; Female; Gadolinium DTPA; Humans; Liver Abscess; Male; Middle Aged; Reference Standards; Retrospective Studies; Time Factors

To evaluate the efficacy of diffusion-weighted imaging (DWI) in differentiating hepatic abscess from malignant mimickers with an emphasis on periphery of the lesions.. 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.. 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.. In addition to conventional MRI, DWI is helpful in differentiating hepatic abscess from malignant mimickers.

Topics: Adult; Aged; Aged, 80 and over; Contrast Media; Diagnosis, Differential; Diffusion Magnetic Resonance Imaging; Female; Gadolinium DTPA; Humans; Liver Abscess; Liver Neoplasms; Male; Middle Aged; Reproducibility of Results; Sensitivity and Specificity; Young Adult