Early Diagnosis and Severity Assessment of Acute Pancreatitis (AP) Using MR Elastography (MRE) With Spin-Echo Echo-Planar Imaging

Purpose: To evaluate the accuracy of magnetic resonance elastography (MRE) in comparison to contrast-enhanced computed tomography (CE-CT) for early diagnosis and prediction of severity in acute pancreatitis (AP). Materials and Methods: This cross-sectional prospective study included 76 patients with suspected AP who underwent both CE-CT and 3.0T MRE within 24 hours of hospital admission. Pancreatic stiffness, CT severity index (CTSI), Acute Physiology and Chronic Health Evaluation (APACHE)-II, and Bedside Index for Severity in AP (BISAP) scores were comparatively evaluated using data from the first 24 hours of admission, and diagnosis and severity of AP were confirmed according to the revised Atlanta Classification (2012). The accuracy of MRE for predicting disease severity was compared with that of CE-CT and the clinical scoring systems using area under the receiver-operating curve (AUC) analysis. Results: AP was confirmed in 56/76 patients (73.7%). Pancreatic stiffness values of >1.47 kPa showed significantly better diagnostic performance than CE-CT (AUC: 0.993 vs. 0.818, P < 0.001) along with greater sensitivity (96.4% vs. 78.6%, P=0.006) and accuracy (96.1% vs. 81.6%, P=0.007). Ten patients (10/76; 13.2%) had clinically severe AP. The accuracy of pancreatic stiffness > 2.47 kPa was comparable to that of the CTSI, APACHE-II and BISAP scores for predicting severe AP (accuracy=85.5%, 75.0%, 88.2%, and 78.9%, respectively). The pairwise comparisons were not significant after Bonferroni correction (P < 0.008 [0.05/6]), with P values of 0.008 (MRE vs. CTSI), 0.823 (MRE vs. APACHE-II) and 0.414 (MRE vs. BISAP). Conclusion: Early MRE is a useful, noninvasive method for both diagnosis and early severity assessment of AP. We recommend MRE at hospital admission for initial evaluation of AP.