Noninvasive prediction of portal pressure with MR elastography and DCE-MRI of the liver and spleen: Preliminary results.

Background: Portal hypertension (PH), defined by hepatic venous pressure gradient (HVPG) >= 5 mmHg and clinically significant PH, defined by HVPG >= 10 mmHg, are complications of chronic liver disease. Purpose: To assess the diagnostic performance of MR elastography (MRE) and dynamic contrast-enhanced MRI (DCE-MRI) of the liver and spleen for the prediction of PH and clinically significant PH, in comparison with a qualitative PH imaging scoring system. Study Type: IRB-approved prospective study. Population: In all, 34 patients with chronic liver disease who underwent HVPG measurement. Field Strength/Sequence: 1.5/3T examination including 2D-GRE MRE (n=33) and DCE-MRI of the liver/spleen (n=28). Assessment: Liver and spleen stiffness were calculated from elastogram maps. DCE-MRI was analyzed using model-free parameters and pharmacokinetic modeling. Two observers calculated qualitative PH imaging scores based on routine images. Statistical Tests: Imaging parameters were correlated with HVPG. Receiver operating characteristic (ROC) analysis was performed for prediction of PH and clinically significant PH. Results: There were significant correlations between DCE-MRI parameters (liver time-to-peak, r=0.517 / P=0.006, liver distribution volume, r=0.494 / P=0.009, liver upslope, r=-0.567 / P=0.002), liver stiffness (r=0.478 / P=0.016), PH imaging score (r=0.441 / P=0.009), and HVPG. ROC analysis provided significant area under the ROC (AUROCs) for PH (liver upslope 0.765, liver stiffness 0.809, spleen volume/diameter 0.746-0.731, PH imaging score 0.756) and for clinically significant PH (liver and spleen perfusion parameters 0.733-0.776, liver stiffness 0.742, PH imaging score 0.742). The ratio of liver stiffness to liver upslope had the highest AUROC for diagnosing PH (0.903) and clinically significant PH (0.785). Data Conclusion: These preliminary results suggest that the combination of liver stiffness and perfusion metrics provide excellent accuracy for diagnosing PH, and fair accuracy for clinically significant PH. Combined MRE and DCE-MRI outperformed qualitative imaging scores for prediction of PH.