New proposal for the staging of nonalcoholic steatohepatitis: evaluation of liver fibrosis on Gd-EOB-DTPA-enhanced MRI

Imaging of focal nodular hyperplastic-like nodules in alcoholic liver cirrhosis patients using gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid magnetic resonance imaging

We report on two patients with a history of alcohol abuse who presented with multiple hepatic nodules. Dynamic computed tomography revealed multiple nodular lesions, which were enhanced at the early contrast phase and washed out at the portal phase. In the hepatobiliary phase using gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid magnetic resonance imaging (Gd-EOB-DTPA MRI), these tumors did not show any uptake, thus suggesting the presence of hepatocellular carcinoma. An ultrasound-guided biopsy revealed a slight increase in cell density, sinusoidal dilatation, and contained unpaired small arteries. According to immunohistochemical analyses, these arteries were positive for CD34 and alpha-smooth muscle actin. From these findings, the nodules were diagnosed to be focal nodular hyperplastic (FNH)-like nodules arising in alcoholic-cirrhosed livers. The differential diagnosis of FNH-like nodules arising in alcoholic liver cirrhosis and hepatocellular carcinoma is difficult with Gd-EOB-DTPA MRI, and therefore histological confirmation is necessary.

Quantitative evaluation of liver function with use of gadoxetate disodium-enhanced MR imaging

PURPOSE

To determine whether liver function correlating with indocyanine green (ICG) clearance could be estimated quantitatively from gadoxetate disodium-enhanced magnetic resonance (MR) images.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board, and the requirement for informed consent was waived. Twenty-three consecutive patients who underwent an ICG clearance test and gadoxetate disodium-enhanced MR imaging with the same parameters as were used for a preoperative examination were chosen. The hepatocellular uptake index (HUI) from liver volume (V(L))and mean signal intensity of the liver on contrast-enhanced T1-weighted images with fat suppression (L(20)) and mean signal intensity of the spleen on contrast-enhanced T1-weighted images with fat suppression (S(20)) on 3D gradient-echo T1-weighted images with fat suppression obtained at 20 minutes after gadoxetate disodium (0.025 mmol per kilogram of body weight) administration was determined with the following equation: V(L)[(L(20)/S(20)) - 1]. The correlation of the plasma disappearance rate of ICG (ICG-PDR) and various factors derived from MR imaging, including HUI, iron and fat deposition in the liver and spleen, and spleen volume (V(S)), were evaluated with stepwise multiple regression analysis. The difference between the ratio of the remnant HUI to the HUI of the total liver (rHUI/HUI) and ratio of the liver remnant V(L) to the total V(L) (rV(L)/V(L)) was evaluated in four patients who had segmental heterogeneity of liver function.

RESULTS

HUI and V(S) were the factors significantly correlated with ICG-PDR (R = 0.87). The mean value and its 95% confidence interval were 0.18 and 0.01 to 0.34, respectively, for the following calculation: (rHUI/HUI) - (rV(L)/V(L)).

CONCLUSION

The liver function correlating with ICG-PDR can be estimated quantitatively from the signal intensities and the volumes of the liver and spleen on gadoxetate disodium-enhanced MR images, which may improve the estimation of segmental liver function.

Staging hepatic fibrosis: comparison of gadoxetate disodium-enhanced and diffusion-weighted MR imaging--preliminary observations

PURPOSE

To evaluate the utility of hepatocyte-phase gadoxetate disodium-enhanced magnetic resonance (MR) imaging in staging hepatic fibrosis and to compare it with diffusion-weighted imaging.

MATERIALS AND METHODS

This retrospective study had institutional review board approval, and the requirement for informed consent was waived. Gadoxetate disodium-enhanced and diffusion-weighted MR images obtained in 114 consecutive patients (70 men, 44 women; age range, 37-91 years) were evaluated. Liver-to-muscle signal intensity (SI) ratio on hepatocyte-phase images (SI(post)), contrast enhancement index calculated as SI(post) /SI(pre), where SI(pre) is liver-to-muscle SI ratio on nonenhanced images, and apparent diffusion coefficient (ADC) of the liver were measured. Necroinflammatory activity grades and hepatic fibrosis stages were histopathologically determined in 99 patients. Multiple regressions of SI(post), contrast enhancement index, ADC, serum albumin concentration, serum total bilirubin level, prothrombin time, and Child-Pugh score were examined to determine correlation with hepatic necroinflammatory activity grades and fibrosis stages.

RESULTS

Among the MR, hematologic, and clinical parameters, contrast enhancement index was most strongly correlated with fibrosis stage (r = -0.79, P < .001). Multiple regression analysis showed that the contrast enhancement index, ADC, and prothrombin time were significantly correlated (r(2) = 0.66, P < .05) with fibrosis stage and that the contrast enhancement index and serum total bilirubin level were weakly correlated (r(2) = 0.24, P < .05) with the necroinflammatory activity grade.

CONCLUSION

Gadoxetate disodium-enhanced MR imaging is more reliable for staging hepatic fibrosis than are diffusion-weighted MR imaging, hematologic, and clinical parameters.

High-field MRI for diagnosis of fatty liver and fat grading: recent research progress

The incidence of fatty liver has been increasing gradually. The development of magnetic resonance imaging (MRI) has increased the sensitivity and specificity for diagnosis of fatty liver. Currently, multiple MRI methods, including fat-suppression sequence, chemical shift, contrast-enhanced MRI and magnetic resonance spectroscopy (MRS), are available for detection and quantification of fatty liver. MR fat-suppression sequence, especially opposed-phase and in-phase chemical shift gradient-echo sequence, is particularly important for detection of fatty liver. MRS is used to quantify liver fat content at the molecular level. In this article, we review the recent progress in research of high-field MRI for diagnosis of fatty liver and fat grading.

Gadoxetate disodium-enhanced MRI of the liver: part 2, protocol optimization and lesion appearance in the cirrhotic liver

OBJECTIVE

The purpose of this article is to review the use of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (gadoxetate disodium [Gd-EOB-DTPA]) in the cirrhotic liver and illustrate the imaging appearance of lesions commonly encountered in the cirrhotic liver.

CONCLUSION

Gd-EOB-DTPA shows promise as a problem-solving tool in the cirrhotic liver because it provides additional information that may be helpful in lesion detection and characterization. Further research is needed to optimize Gd-EOB-DTPA imaging protocols in cirrhosis and develop diagnostic criteria for liver lesions in the cirrhotic liver.