Gadolinium Ethoxybenzyl Diethylenetriamine Pentaacetic Acid Research Articles

MR prediction of liver fibrosis using a liver‐specific contrast agent: Superparamagnetic iron oxide versus Gd‐EOB‐DTPA

To examine whether the uptake of a liver-specific contrast agent in the liver parenchyma was correlated with the degree of liver fibrosis. This retrospective study included 54 and 63 patients who underwent superparamagnetic iron oxide (SPIO)- and gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MRI before liver surgery, respectively. For each patient, we calculated ΔR2* and ΔR2, which represent differences in R2* and R2 values of the liver parenchyma before and after administration of SPIO; and the increase rate of liver-to-spleen signal intensity ratio (LSR) on the hepatobiliary phase compared with the precontrast image. The correlation of each MR parameter with the degree of liver fibrosis (F0 to F4) was assessed using Spearman's rank correlation test. The increase rate of LSR was best correlated with the degree of liver fibrosis and significantly decreased as the liver fibrosis progressed (rho = -0.641; P < 0.0001). It showed sensitivity of 76.9% and specificity of 83.3% in differentiating F3 or greater fibrosis when 1.126 or less was set up as a cut-off value. No significant correlation was obtained between ΔR2* or ΔR2 and the degree of liver fibrosis. The uptake of Gd-EOB-DTPA in the liver parenchyma decreased as the liver fibrosis progressed. J. Magn. Reson. Imaging 2012;36:664-671. © 2012 Wiley Periodicals, Inc.

Assessment of Gd-EOB-DTPA-enhanced MRI for HCC and dysplastic nodules and comparison of detection sensitivity versus MDCT

We aimed to evaluate gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) for the detection of hepatocellular carcinomas (HCCs) and dysplastic nodules (DNs) compared with dynamic multi-detector row computed tomography (MDCT), and to discriminate between HCCs and DNs. Eighty-six nodules diagnosed as HCC or DNs were retrospectively investigated. Gd-EOB-DTPA-enhanced MRI and dynamic MDCT were compared with respect to their diagnostic ability for hypervascular HCCs and detection sensitivity for hypovascular tumors. The ability of hepatobiliary images of Gd-EOB-DTPA-enhanced MRI to discriminate between these nodules was assessed. We also calculated the EOB enhancement ratio of the tumors. For hypervascular HCCs, the diagnostic ability of Gd-EOB-DTPA-enhanced MRI was significantly higher than that of MDCT for tumors less than 2 cm (p = 0.048). There was no difference in the detection of hypervascular HCCs between hepatobiliary phase images of Gd-EOB-DTPA-enhanced MRI (43/45: 96%) and dynamic MDCT (40/45: 89%), whereas the detection sensitivity of hypovascular tumors by Gd-EOB-DTPA-enhanced MRI was significantly higher than that by dynamic MDCT (39/41: 95% vs. 25/41: 61%, p = 0.001). EOB enhancement ratios were decreased in parallel with the degree of differentiation in DNs and HCCs, although there was no difference between DNs and hypovascular well-differentiated HCCs. The diagnostic ability of Gd-EOB-DTPA-enhanced MRI for hypervascular HCCs less than 2 cm was significantly higher than that of MDCT. For hypovascular tumors, the detection sensitivity of hepatobiliary phase images of Gd-EOB-DTPA-enhanced MRI was significantly higher than that of dynamic Gd-EOB-DTPA-enhanced MRI and dynamic MDCT. It was difficult to distinguish between DNs and hypovascular well-differentiated HCCs based on the EOB enhancement ratio.

Potential clinical factors affecting hepatobiliary enhancement at Gd-EOB-DTPA-enhanced MR imaging

ObjectiveThe objective was to clarify the clinical factors that might affect the degree of hepatic parenchymal enhancement at gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance (MR) imaging. Materials and MethodsA total of 84 patients with (n=63) and without chronic liver disease (n=21) underwent Gd-EOB-DTPA-enhanced MR imaging. Contrast-enhanced MR images of hepatobiliary phase (HP) were obtained at 20 min after Gd-EOB-DTPA administration. The relative enhancement (RE) of liver parenchyma at 20 min HP was calculated from region of interest measurements at each patient. Then, these results were correlated with various clinical parameters using Pearson correlation coefficient or Spearman rank correlation coefficient. Furthermore, the predictor of the degree of hepatic parenchymal enhancement was determined using multiple regression analysis. ResultsThe presence or absence of chronic liver disease (P=.002), ascites (P=.005) and splenomegaly (P=.027), and the values of prothrombin activity (P=.008), total bilirubin (T-Bil) (P=.001), albumin (P=.001), aspartate aminotransferase (AST) (P=.002) and cholinesterase (P=.007) were significantly correlated with the RE of liver parenchyma at 20 min HP. Among these parameters, increases of T-Bil (P=.011 to .028) and AST (P=.018 to .049) were predictors of decreased hepatic parenchymal enhancement. ConclusionsHepatic parenchymal enhancement of Gd-EOB-DTPA was affected by various clinical parameters. Impaired hepatobiliary enhancement may be predicted by routine biochemical tests, such as T-Bil and AST.

Correlation of liver parenchymal gadolinium-ethoxybenzyl diethylenetriaminepentaacetic acid enhancement and liver function in humans with hepatocellular carcinoma

Animal studies have demonstrated that liver function parameters affect the degree of liver enhancement by gadolinium-ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA). The present study prospectively investigated whether liver function parameters and liver damage scores similarly correlate with the degree of liver enhancement by Gd-EOB-DTPA in humans with hepatocellular carcinoma (HCC). A total of 41 patients (32 males, 9 females; mean age, 71.9 years; range, 38-86 years) with suspected HCC provided written, informed consent to undergo a Gd-EOB-DTPA (30 μmol/kg of body weight)-enhanced T1-gradient-echo (GRE) magnetic resonance imaging (MRI) study. The signal intensity of the liver parenchyma was quantified at various time points following injection of Gd-EOB-DTPA. We investigated the correlations between maximal relative enhancement (RE) values and liver function parameters, and liver damage scores. Correlations between parameters and maximum RE values were determined using the Student's t-test and univariate regression analyses. The effect of potential confounding factors was controlled by multiple stepwise regression analysis. Two-tailed values of p<0.05 were considered to indicate a statistically significant difference. The RE values were maximal in 8 and 33 patients at 20 and 30 min, respectively, following Gd-EOB-DTPA injection and did not significantly differ between respective liver damage scores. Univariate analyses revealed that maximal RE values were associated with serum aspartate aminotransferase, total bilirubin, albumin and 15-min indocyanine green retention rates. Multiple stepwise regression analyses revealed that serum albumin and total bilirubin remained independently significant. The degree of liver parenchyma enhancement by Gd-EOB-DTPA depends on liver function parameters in humans, as in animals. The results from this study suggest that Gd-EOB-DTPA has potential for use as a liver function test, and for providing a short examination time for liver MRI results in patients with normal liver function.

Hepatic parenchymal enhancement at Gd-EOB-DTPA-enhanced MR imaging: correlation with morphological grading of severity in cirrhosis and chronic hepatitis

The aim was to clarify whether enhancement effects of the liver parenchyma in the hepatobiliary phase (HP) of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MR imaging were correlated with the morphological grading of the severity in cirrhosis. A total of 62 patients with chronic hepatitis or cirrhosis underwent Gd-EOB-DTPA-enhanced MR imaging. Relative enhancement (RE) of liver parenchyma was calculated from signal intensity (SI) measurements obtained at precontrast images (SIpre) and 20-min postcontrast HP images (SIpost) as: (SIpost−SIpre)/SIpre. Morphological MR grades of severity in cirrhosis were divided into four groups. Then, RE of liver parenchyma and morphologic MR grading were correlated. Regarding the morphologic severity of cirrhosis, the numbers of patients with MR grade 1, 2, 3 and 4 were 14 (23%), 7 (11%), 28 (45%) and 13 (21%), respectively. The mean REs of liver parenchyma in each group of MR morphologic grade 1, 2, 3 and 4 were 0.71±0.21, 0.62±0.16, 0.70±0.22 and 0.77±0.18, respectively. There was no significant correlation between the MR grading of morphologic severity and the RE of liver parenchyma at 20-min HP. Hepatic parenchymal enhancement in the HP of Gd-EOB-DTPA-enhanced MR imaging did not necessarily decrease according to the severity of morphologic changes in cirrhosis. This fact may suggest that the hepatic uptake of Gd-EOB-DTPA depends on the preserved hepatocytes function rather than the severity of morphologic changes in cirrhosis.

Early phase detection of bile leak after hepatobiliary surgery: value of Gd-EOB-DTPA-enhanced MR cholangiography

To assess the value of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced MR cholangiography for the detection of bile leaks after hepatobiliary surgery. Twenty-three patients with symptoms suggestive of bile leak underwent conventional fat-suppressed T1- and T2-weighted MR cholangiography followed by Gd-EOB-DTPA-enhanced MR cholangiography using gradient-echo (GRE) T2-weighted sequences and fat-suppressed T1-weighted 3D gradient-echo sequences 20min after an intravenous bolus of Gd-EOB-DTPA. The results of Gd-EOB-DTPA-enhanced MR cholangiography correlated with clinical findings, surgical repair, and the results of endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography. The results of Gd-EOB-DTPA-enhanced MR cholangiography were negative in 13 patients (cholecystectomy 5, liver transplantation 2, liver resection for focal lesions 2, cholangiocarcinoma 1, and partial hepatectomy after liver injury 1). In 10 patients in whom bile leaks were detected, this complication occurred after liver resection for focal lesions in 3, cholecystectomy in 4, liver transplantation in 2, and liver resection for intrahepatic cholangiocarcinoma in 1. The diagnostic accuracy of Gd-EOB-DTPA-enhanced MR for the detection or exclusion of bile leaks was 100%. Gd-EOB-DTPA-enhanced MR cholangiography is a highly reliable technique for the detection of bile leaks after hepatobiliary surgery and may avoid the use of other, potentially risky invasive diagnostic techniques.

Evaluation of Concanavalin A-induced Acute Liver Injury in Rats using an Empirical Mathematical Model and Dynamic Contrast-enhanced MR Imaging with Gd-EOB-DTPA

We evaluated concanavalin A (Con A)-induced acute hepatic injury in rats using an empirical mathematical model (EMM) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA). We allocated 18 rats into 3 groups of six each and intravenously injected them with either 10 mg/kg body weight (BW) of Con A (Con A [10] group), 20 mg/kg BW of Con A (Con A [20] group), or a single dose of of saline (4 mL/kg BW, normal control group). We performed the DCE-MRI studies using Gd-EOB-DTPA (0.025 mmol Gd/kg; 0.1 mL/kg BW) as the contrast agent 24 hours after injection of Con A or saline. We then sampled blood, measured serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and calculated the rate of contrast uptake (α), rate of contrast washout (β), area under the curve (AUC), time to maximum relative enhancement (RE) (T(max)), and elimination half-life of RE (T(1/2)) from the time-signal intensity curves using the EMM. β values were significantly smaller in the Con A (10) and Con A (20) groups than the control group, but α did not differ significantly among the 3 groups. The AUC value was significantly greater in the Con A (10) group than controls, and the T(max) and T(1/2) values were significantly greater in the Con A (20) group than controls. The β, T(max), and T(1/2) values correlated significantly with AST and ALT. In conclusion, the EMM is useful for evaluating Con A-induced acute hepatic injury using DCE-MRI with Gd-EOB-DTPA.

Efficacy of Fusion Imaging Combining Sonography and Hepatobiliary Phase MRI With Gd-EOB-DTPA to Detect Small Hepatocellular Carcinoma

We evaluated the efficacy of fusion imaging that fuses conventional sonography images with hepatobiliary phase contrast-enhanced MR images obtained with gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) as the reference image for the detection of hepatocellular carcinomas (HCCs). Eighty-seven HCCs with a maximum diameter of between 1 and 3 cm at the time of diagnosis were enrolled in this prospective study. We compared the detection rates of HCCs using three sonography modalities: conventional sonography, late phase of contrast-enhanced sonography with Sonazoid, and fusion imaging combining conventional sonography and the hepatobiliary phase of contrast-enhanced MRI with Gd-EOB-DTPA as the reference image. The comparisons were made using the McNemar test. The detection rate of HCCs using fusion imaging (98%, 85/87) was significantly higher than the detection rates using conventional sonography (76%, 66/87) and contrast-enhanced sonography (83%, 72/87) (p<0.01, for both). For small HCCs (maximum diameter, 1-2 cm), the detection rate using fusion imaging (97%, 59/61) was also significantly higher than those using conventional sonography (66%, 40/61) and contrast-enhanced sonography (80%, 49/61) (p<0.01, for both). The detection rate for atypical HCCs was also significantly higher using fusion imaging (95%, 18/19) than using conventional sonography (53%, 10/19) and contrast-enhanced sonography (26%, 5/19) (p<0.01, for both). Fusion imaging combining conventional sonography and the hepatobiliary phase of contrast-enhanced MRI with Gd-EOB-DTPA is more sensitive than conventional sonography or contrast-enhanced sonography for detecting HCCs, especially small or atypical HCCs.

CT versus MR Imaging of Hepatocellular Carcinoma: Toward Improved Treatment Decisions

Detection, characterization, staging, and treatment monitoring are major roles of diagnostic imaging of liver cancers. Developments in multidetector-row computed tomography (MDCT) technology have increased the spatial and temporal resolution of CT to allow more precise evaluation of the hemodynamics of liver tumors and improve the diagnostic accuracy of dynamic MDCT. The high spatial and temporal resolutions of dynamic MDCT enable us to reconstruct 3-dimensional (3D) images that are very useful for pretreatment evaluation. Dynamic MR imaging with fast 3D T(1)-weighted gradient echo imaging sequence using nonspecific contrast medium can be highly sensitive for detecting hypervascular HCC. However, the use of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA), a contrast medium specific to hepatic tissue, offers greater diagnostic ability and, so, has become essential to liver imaging. MR imaging with Gd-EOB-DTPA may replace CT during hepatic arteriography and CT during arterioportography.

MDIXONにおけるFlip AngleおよびEcho Timeの組み合わせによる水・脂肪分離効果およびコントラストの検討

The method known as DIXON is imaging from two different echo times (TE), using the opposite phase of water and fat. Modified DIXON (mDIXON) is the method that is calculated from changing the opposing phases 'in' and 'opposed' phases of the actual measurement, to fit the theoretical value. We reviewed that the effect of the water-fat separation and contrast depended on the different flip angles (FA) and echo times (TE). The diluted gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) (from 0 to 5 mmol/l) and liver model was stabilized by lard. In order to measure the SNR and %CV of the lard, the various combinations of TE and FA (from 5 to 20 degrees) were changed. The suitable range for the measurement of the SNR and %CV of the lard, and the contrast of gadolinium Gd-EOB-DTPA and the liver model, in the axial view (including 50% fat), was around the 'opposed' phase in the first TE (TE1) and around the 'in' phase in the second TE (TE2) and FA: 15degrees (TE1: 2.0-2.9 ms, TE2: 4.1-5.0 ms). In order to avoid phase dispersion, shorter TE range is more desirable (TE1: 2.0-2.25 ms, TE2: 4.1-4.5 ms). It is our understanding that the water-fat separation is better in these ranges and under these circumstances, good contrast was obtained.

Well-differentiated Hepatocellular Carcinoma Detected as Hypovascularity by Only CT during Hepatic Arteriography

We describe a well-differentiated hepatocellular carcinoma (HCC) with alcohol-related liver cirrhosis in a 69-year-old man. Ultrasonography (US) disclosed a 10 mm hypoechoic nodule in segment 4; Sonazoid contrast-enhanced US and gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) revealed no defect in either the Kupffer phase or the hepatobiliary phase. Computed tomography during hepatic arteriography (CTHA), however, revealed a hypovascular nodule, but CT during arterial portography showed no perfusion defect. Histological analysis indicated a well-differentiated HCC. Thus, our detection of well-differentiated HCC disclosed by only CTHA attested to the efficiency of this modality, suggesting that it is more sensitive than Gd-EOB-GTPA-enhanced MRI.

Typical and Atypical Imaging Findings of Intrahepatic Cholangiocarcinoma Using Gadolinium Ethoxybenzyl Diethylenetriamine Pentaacetic Acid–Enhanced Magnetic Resonance Imaging

The objective of this study was to examine the imaging features of classic mass-forming intrahepatic cholangiocarcinoma (MICC) and nonclassic hypervascular MICC on gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging. Twenty pathologically confirmed MICCs were included. Two radiologists retrospectively reviewed the imaging characteristics on T2-weighted imaging, diffusion-weighted imaging, dynamic contrast-enhanced images, and hepatobiliary phase (HBP) of each MICC. For the morphologic feature of defect, HBP signal intensity (SI) ratio was calculated by dividing the SI of the MICC by nearby normal liver parenchyma SI. Classic MICCs (n = 14) showed classic rim or peripheral enhancement at arterial dominant phase with centripetal enhance in the delayed phases. Hypervascular MICCs (n = 6) showed complete (n = 4) or near-complete (n = 2) arterial enhancement and washout (n = 6) on delayed phases. On HBP, 13 classic MICCs (93%) and 2 hypervascular MICCs (33%) showed cloud-like SI in the center ("EOB cloud") with peripheral defect. Mean SI ratio was 0.77 in classic MICCs and 0.59 in hypervascular MICC (P = 0.057). Classic MICCs (70%) frequently showed progressive centripetal enhancement on dynamic phase, and central EOB-cloud appearance with distinct peripheral defect on HBP. Nonclassic hypervascular MICCs comprised 30% of the MICCs in this study. Compared with classic MICCs, hypervascular MICCs showed wash-in on arterial dominant phase and washout on delayed phase.

Possible utility of MRI using Gd-EOB-DTPA for estimating liver functional reserve

Preoperative estimation of the liver functional reserve is important in liver surgery. We evaluated the role of dynamic magnetic resonance (MR) imaging with gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA), i.e., EOB-MRI, for determining liver functional reserve. Fifty patients who underwent EOB-MRI to examine their liver tumors were included in this study. We first performed a pixel-by-pixel comparison of registered MR images and activity images with Tc-99m galactosyl human serum albumin (GSA) on each slice, and the correlation coefficient was calculated for 8 patients. We also determined the correlation coefficient between the relative signal intensity (SI) values of EOB-MRI and preoperative liver function, such as the GSA, indocyanine green dye retention at 15 min (ICGR15), and prothrombin time. The mean of the correlation coefficients for 512 × 512 matrices between the EOB-MRI and the GSA was 0.83 ± 0.05 (ranging from 0.73 to 0.87). The correlation coefficient between the relative SI of the EOB-MRI and the receptor index (LHL15) of GSA was 0.56 (P < 0.01). Better correlation coefficients were observed between the relative SI and the liver function test, including ICGR15 (r = -0.67, P < 0.01) and prothrombin time (r = 0.59, P < 0.01). In a patient with hilar cholangiocarcinoma whose right hepatic duct was obstructed, the relative SI in the right lobe (2.4 ± 0.3) was significantly lower than that in the left lobe (3.1 ± 0.1). EOB-MRI represents a practical and reliable imaging technique that may be used to estimate regional liver functional reserve in the clinical setting.

Combining diffusion-weighted MRI with Gd-EOB-DTPA-enhanced MRI improves the detection of colorectal liver metastases

To compare the diagnostic accuracy of gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced MRI, diffusion-weighted MRI (DW-MRI) and a combination of both techniques for the detection of colorectal hepatic metastases. 72 patients with suspected colorectal liver metastases underwent Gd-EOB-DTPA MRI and DW-MRI. Images were retrospectively reviewed with unenhanced T(1) and T(2) weighted images as Gd-EOB-DTPA image set, DW-MRI image set and combined image set by two independent radiologists. Each lesion detected was scored for size, location and likelihood of metastasis, and compared with surgery and follow-up imaging. Diagnostic accuracy was compared using receiver operating characteristics and interobserver agreement by kappa statistics. 417 lesions (310 metastases, 107 benign) were found in 72 patients. For both readers, diagnostic accuracy using the combined image set was higher [area under the curve (Az)=0.96, 0.97] than Gd-EOB-DTPA image set (Az=0.86, 0.89) or DW-MRI image set (Az=0.93, 0.92). Using combined image set improved identification of liver metastases compared with Gd-EOB-DTPA image set (p<0.001) or DW-MRI image set (p<0.001). There was very good interobserver agreement for lesion classification (κ=0.81-0.88). Combining DW-MRI with Gd-EOB-DTPA-enhanced T(1) weighted MRI significantly improved the detection of colorectal liver metastases.

Peripheral low intensity sign in hepatic hemangioma: Diagnostic pitfall in hepatobiliary phase of Gd‐EOB‐DTPA‐enhanced MRI of the liver

To describe the presence of "peripheral low intensity sign" in hepatic hemangioma in the hepatobiliary phase (HP) of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and to compare the frequency of this sign between hepatic hemangiomas and hepatic metastases. The Institutional Review Board approved this study and waived the requirement for informed consent. Sixty-four patients with 51 hepatic hemangiomas (n = 31 patients) and with 58 hepatic metastases (n = 33 patients) underwent Gd-EOB-DTPA-enhanced MRI. In all hepatic hemangiomas, 41 lesions were the typical type and 10 were the high flow type. HP images were qualitatively evaluated for the frequency of peripheral low intensity sign in hepatic hemangiomas and hepatic metastases using a four-point scale. Statistical evaluations were performed with a Mann-Whitney U-test. Peripheral low intensity signs were demonstrated in 24 (47%) of 51 hepatic hemangiomas, while they were seen in 27 (47%) of 58 hepatic metastases. There was no significant difference in the mean visual score of peripheral low intensity sign between all hepatic hemangiomas (0.84 ± 1.03) and hepatic metastases (0.76 ± 0.92). The mean visual score of peripheral low intensity sign in typical hemangiomas (1.02 ± 1.06) was significantly higher than that in high flow hemangiomas (0.10 ± 0.32) (P = 0.008). Peripheral low intensity sign is not specific for malignant tumors, and can be seen even in hepatic hemangiomas on HP of Gd-EOB-DTPA-enhanced MRI.

Ring-like enhancement of focal nodular hyperplasia with hepatobiliary-phase Gd-EOB-DTPA-enhanced magnetic resonance imaging: radiological-pathological correlation

We report a case of focal nodular hyperplasia in a patient for whom gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and histological analysis results were available. Dynamic contrast-enhanced computed tomography showed a well-defined hypervascular lesion 14 mm in diameter with no visible central scars. Gd-EOB-DTPA-enhanced MRI demonstrated strong peripheral enhancement of the lesion during the hepatobiliary phase, resulting in ring-like enhancement. The pathology examination revealed that the lesion was focal nodular hyperplasia (FNH). Immunohistochemistry showed positive expression of OATP8 in the hepatocytes in the peripheral areas of the lesion, whereas expression of OATP8 was lacking in hepatocytes surrounding the central radiating scar. Ring-like enhancement during the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI may be an important clue for the diagnosis of small FNH.

Uptake of gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic acid in metastatic adrenal tumour from hepatocellular carcinoma

We present the case of a metastatic adrenal tumour from hepatocellular carcinoma (HCC) showing the uptake of gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA) on MRI. To our knowledge, this is the first case of metastatic HCC in which Gd-EOB-DTPA uptake was shown on MRI and this finding facilitated the accurate pre-operative diagnosis of a metastatic adrenal tumour.

Assessment of fast dynamic imaging and the use of Gd‐EOB‐DTPA for MR‐guided liver interventions

1) To analyze and compare fast dynamic imaging sequences to biopsy suspect liver lesions. 2) To evaluate the additional use of hepatocyte-specific contrast agent compared to the nonenhanced fast dynamic scans and diagnostic liver imaging. Image acquisition was performed using a 1T open-configured scanner suitable for interventional purposes. Transversal postcontrast T1-weighted (T1w) fat-saturated 3D high-resolution examination (THRIVE) images were acquired >20 minutes postintravenous application of gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid (Gd-EOB-DTPA). A single slice, crossing the level of the lesion, was acquired using intermediate-weighted steady-state free-precession (bTFE), T1w-gradient echo and spin echo (T1FFE/TSE), T2w-spin echo (sshTSE) sequences. T1w imaging was acquired prior and after contrast media application. Diagnostic and fast dynamic images were compared based on a 10-point rating scale. In addition, the liver-to-lesion-contrast ratio was measured. A total of 39 malignant lesions with a mean diameter of 13 mm (5-30 mm) in 39 patients were included. Concerning a test of noninferiority, there was no significant difference between rating score values of fast dynamic imaging employing contrast-enhanced T1FFE-sequences compared to diagnostic THRIVE (P = 0.001). Calculated liver-to-lesion contrast also showed no difference for either imaging sequence (P = 1.0). All other sequences tested showed significant inferiority (P ≤ 0.001). T1w Gd-EOB-DTPA contrast-enhanced fast dynamic GRE imaging significantly improves the contrast behavior of malignant liver lesions comparable to diagnostic imaging and is best suited for liver intervention, especially at 1T open magnetic resonance imaging.

Gd-EOB-DTPA-enhanced 3.0 T MR imaging: quantitative and qualitative comparison of hepatocyte-phase images obtained 10 min and 20 min after injection for the detection of liver metastases from colorectal carcinoma

To compare quantitatively and qualitatively hepatocyte-phase images obtained 10 and 20 min (Images-10, and Images-20) after injection of gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic acid (Gd-EOB-DTPA) to detect liver metastases from colorectal carcinoma on 3.0 T MR imaging. A total of 48 patients (26 men, 22 women; mean age, 64 years) with 88 histopathologically confirmed liver metastases underwent Gd-EOB-DTPA-enhanced MR imaging. Tumour-to-liver contrast-to-noise ratio (CNR), signal intensity gain (SIG) of liver parenchyma and overall image quality were analysed. Two radiologists independently reviewed two sets of MR images: set 1, unenhanced (T1- and T2-weighted), dynamic images and Images-10; set 2, unenhanced, dynamic and Images-20. Sensitivity and positive predictive value (PPV) to detect liver metastases, and diagnostic performance using the alternative free-response receiver operating characteristics (AFROC) method were calculated. The mean tumour-to-liver CNR, SIG of liver parenchyma and overall image quality on Images-20 were significantly higher than those on Images-10. The overall image quality of "fair to excellent" was achieved on both images in 93.8% of the patients. Sensitivity, PPV and area under the AFROC curve on set 1 were similar to set 2, including lesions <1 cm. In detecting liver metastases from colorectal carcinoma, Images-10 could replace Images-20 in 3.0 T MR imaging.

Gd-EOB-DTPA as a Functional MR Cholangiography Contrast Agent: Imaging Gallbladder Filling in Patients With and Without Hepatobiliary Dysfunction

To evaluate cystic duct patency on hepatobiliary-phase magnetic resonance (MR) images after intravenous gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA) administration. A radiology information system search identified patients with gallbladders that had MR imaging after intravenous Gd-EOB-DTPA injection. No patients had acute cholecystitis. Magnetic resonance image findings were correlated with clinical notes, other imaging studies, time of contrast injection, and serum laboratory tests. Contrast accumulated in the gallbladder in 80% of patients (n = 100) with hepatobiliary-phase MR imaging at a median of 22 minutes (range, 15-83 minutes). Absence of contrast accumulation in the gallbladder (n = 20) was associated with hepatobiliary imaging less than 30 minutes after contrast administration, gallbladder contraction, cholelithiasis, elevated liver function tests, elevated bilirubin, and cirrhosis. Functional assessment of cystic duct patency by Gd-EOB-DTPA-enhanced liver MR is best conducted when hepatobiliary-phase T1-weighted imaging is delayed by more than 30 minutes after contrast injection. Hepatobiliary dysfunction is associated with nonfilling of the gallbladder.