Does the Functional Liver Imaging Score Derived from Gadoxetic Acid-enhanced MRI Predict Outcomes in Chronic Liver Disease?

Background Gadoxetic acid-enhanced MRI enables estimation of liver function in patients with chronic liver disease (CLD). The functional liver imaging score (FLIS), derived from gadoxetic acid-enhanced MRI, has been shown to predict transplant-free survival in liver transplant patients. Purpose To investigate the accuracy of the FLIS for predicting hepatic decompensation and transplant-free survival in patients with CLD. Materials and Methods Patients with CLD who had undergone gadoxetic acid-enhanced liver MRI, including T1-weighted volume-interpolated breath-hold examination sequences with fat suppression, performed between 2011 and 2015 were included. FLIS was assigned on the basis of the sum of three hepatobiliary phase features, each scored on an ordinal 0-2 scale: hepatic enhancement, biliary excretion, and the signal intensity in the portal vein. Patients were stratified into the following three groups according to fibrosis stage and a presence or history of hepatic decompensation: nonadvanced CLD, compensated advanced CLD (CACLD), and decompensated advanced CLD (DACLD). The predictive value of FLIS for first and/or further hepatic decompensation and for transplant-free survival was investigated by using Kaplan-Meier analysis, log-rank tests, and Cox regression analysis. Results This study evaluated 265 patients (53 years ± 14 [standard deviation]; 164 men). Intraobserver (κ = 0.98; 95% confidence interval: 0.97, 0.99) and interobserver (κ = 0.93; 95% confidence interval: 0.90, 0.95) agreement for FLIS were excellent. In patients with CACLD, the FLIS was independently predictive of a first hepatic decompensation (adjusted hazard ratio, 3.7; 95% confidence interval: 1.1, 12.6; P = .04), but not for further hepatic decompensations in patients with DACLD (adjusted hazard ratio, 1.4; 95% confidence interval: 0.9, 1.9; P = .17). The FLIS was an independent risk factor for mortality in both patients with CACLD (adjusted hazard ratio, 7.4; 95% confidence interval: 2.7, 20.2; P < .001) and those with DACLD (adjusted hazard ratio, 3.8; 95% confidence interval: 1.7, 9.5; P = .004). Conclusion The functional liver imaging score derived from gadoxetic acid-enhanced MRI identified patients with advanced chronic liver disease who are at increased risk for a first hepatic decompensation and for mortality. © RSNA, 2019 Online supplemental material is available for this article.

Noninvasive differentiation of simple steatosis and steatohepatitis by using gadoxetic acid-enhanced MR imaging in patients with nonalcoholic fatty liver disease: a proof-of-concept study.

PURPOSE: To determine whether gadoxetic acid-enhanced magnetic resonance (MR) imaging can be used to distinguish between simple steatosis and nonalcoholic steatohepatitis (NASH) in patients with nonalcoholic fatty liver disease (NAFLD), defined according to the steatosis activity and fibrosis (SAF) scoring system, which is based on the semiquantitative scoring of steatosis activity and liver fibrosis. MATERIALS AND METHODS: The local institutional review committee approved this study and waived written informed consent. This was a retrospective study of gadoxetic acid-enhanced 3-T MR imaging performed in 81 patients with NAFLD (45 men [56%]; mean age, 56 years; range, 25-78 years). The MR images were analyzed by using the relative enhancement (the ratio of signal intensities of the liver parenchyma before and 20 minutes after intravenous administration of gadoxetic acid). Univariate and multiple regression analyses were applied to identify variables associated with relative enhancement measurements. The ability of relative enhancement to allow differentiation between simple steatosis and NASH was assessed by using area under the receiver operating characteristic (ROC) curve analysis. RESULTS: Relative enhancement negatively correlated with the degree of lobular inflammation (r = -0.59, P < .0001), ballooning (r = -0.44, P < .0001), and fibrosis (r = -0.59, P ≤ .0001), but not with steatosis (r = -0.16, P = .15). Patients with NASH had a significantly lower relative liver enhancement (0.82 ± 0.22) than those with simple steatosis (1.39 ± 0.52) (P < .001). Relative enhancement measurements performed well in the differentiation between simple steatosis and NASH, with an area under the ROC curve of 0.85 (95% confidence interval: 0.75, 0.91) (cutoff = 1.24, sensitivity = 97%, specificity = 63%). CONCLUSION: Gadoxetic acid relative enhancement was significantly lower in patients with NASH than in patients with simple steatosis, but further prospective studies are warranted.

Assessment of Orthotopic Liver Transplant Graft Survival on Gadoxetic Acid-Enhanced Magnetic Resonance Imaging Using Qualitative and Quantitative Parameters.

OBJECTIVE: The aim of this study was to evaluate the prognostic potential of a 3-parameter visual scoring (qualitative score [QS]) system for hepatobiliary phase gadoxetic acid-enhanced magnetic resonance imaging (MRI) in orthotopic liver transplant grafts. MATERIALS AND METHODS: This retrospective study of 128 patients was approved by our institutional review board. Two readers independently assigned 3 QSs to T1-weighted MRI scans, 20 minutes after the administration of gadoxetic acid (hepatobiliary phase), based upon the following: (1) liver parenchymal enhancement (EnQS, 0-2); (2) biliary contrast excretion (ExQS, 0-2); and (3) signal intensity of the portal vein relative to the liver parenchyma, that is, the portal vein sign (PVsQS, 0-2). The functional liver imaging score (FLIS) was calculated as the sum score of these 3 parameters. The relative liver enhancement (RLE) was measured as well. Demographic, clinical, laboratory parameters, and imaging findings were included in univariate and multivariate statistical analyses. The primary end point was graft failure, that is, retransplantation or death from liver failure. The probability of graft survival was calculated by Kaplan-Meier estimates and Cox proportional hazards regression. RESULTS: In the univariate analysis, EnQS, ExQS, PVsQS, and FLIS scores, as well as RLE, were significantly associated with the 1- to 3-year probability of graft survival (P < 0.001). For a FLIS of (0), the 3-year probability of graft survival was 6.5%, whereas it was 51.3% for a FLIS of (1-3) and 100% for a FLIS of (4-6) (P < 0.001). In the multivariate survival models, EnQS, ExQS, and PVsQS, each independently outperformed the majority of clinical and laboratory parameters, and the FLIS did even better regarding the prediction of 1- to 3-year graft survival. CONCLUSIONS: In liver transplant recipients, gadoxetic acid-enhanced MRI-derived QSs (ie, EnQS, ExQS, and PVsQS), as well as the FLIS and RLE, can predict graft survival probability.

Magnetic field interactions of copper-containing intrauterine devices in 3.0-Tesla magnetic resonance imaging: in vivo study.

OBJECTIVE: An ex vivo study found a copper-containing intrauterine device (IUD) to be safe for women undergoing an MRI examination at a 3.0-T field. No significant artifacts caused by the metallic implant were detected. However, there are still no in vivo data about these concerns. The aim of this study was to evaluate 3.0-T magnetic field interactions of copper-containing IUDs in vivo. MATERIALS AND METHODS: Magnetic field interactions and potential adverse events were evaluated in 33 women using a questionnaire-based telephone survey. Two experienced radiologists performed artifact evaluation on MR images of the pelvis. RESULTS: Eighteen patients were eligible for the survey. One patient reported a dislocation of the IUD after the MR examination. All other patients had no signs of field interactions. No IUD-related artifacts were found. CONCLUSION: MRI at 3.0-T is possible for women with copper-containing IUDs. However, consulting a gynecologist to check the correct position of the IUD and exclude complications after an MR examination is highly recommended. High-quality clinical imaging of the female pelvis can be performed without a loss in image quality.