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BACKGROUND Liver fibrosis is characterized by the excessive accumulation of extracellular matrix proteins. Electrical conductivity imaging at low frequency can provide novel contrast because the contrast mechanisms originate from the changes in the concentration and mobility of ions in the extracellular space. PURPOSE To evaluate the feasibility of an MR-based electrical conductivity imaging that can detect the changes in a tissue condition associated with the progression of liver fibrosis. STUDY TYPE Prospective phantom and animal study. ANIMAL MODEL Fibrosis was induced by weekly intraperitoneal injection of dimethylnitrosamine (DMN) in 45 male Sprague-Dawley rats. FIELD STRENGTH/SEQUENCE 3T MRI with a multispin-echo pulse sequence. ASSESSMENT The percentage change of conductivity (Δσ, %) in the same region-of-interest (ROI) was calculated from the DMN-treated rats based on the values of the normal control rats. The percentage change was also calculated between the ROIs in each DMN-treated group. STATISTICAL TESTS One-way analysis of variance (ANOVA) and a two-sample t-test were performed. RESULTS Liver tissues in normal control rats showed a uniform conductivity distribution of 56.6 ± 4.4 (mS/m). In rats more than 5 weeks after induction, the fibrous region showed an increased conductivity of ≥12% compared to that of the corresponding normal control rats. From regional comparisons in the same liver, the fibrous region showed an increased conductivity of ≥11% compared to the opposite, less induced region of rats more than 5 weeks after induction. Liver samples from the fibrous region represent tissue damages such as diffuse centrilobular congestion with marked dilatation of central veins from the histological findings. Immunohistochemistry revealed significant levels of attenuated fibrosis and increased inflammatory response. DATA CONCLUSION The increased conductivity in the fibrous region is related to the changes of the extracellular space. The correlation between the collagen deposition and conductivity changes is essential for future clinical studies. Level of Evidence 2 Technical Efficacy Stage 2 J. MAGN. RESON. IMAGING 2021;53:554-563.

Gastric infarction is a rare complication of acute pancreatitis. The proposed mechanism underlying this condition is a marked reduction of blood supply due to thrombotic occlusion of the vascular system. A review of the medical literature published thus far identified three reported cases of gastric infarction caused by acute pancreatitis. We report an additional case of gastric and splenic infarctions caused by acute pancreatitis in a 63-year-old woman. Laboratory investigation revealed increases of serum amylase, serum lipase, serum lactate dehydrogenase, blood urea nitrogen, blood creatinine, and blood C-reactive protein levels, as well as increases in the white blood cell count, indicating acute severe pancreatitis. Abdominal computed tomography revealed acute necrotic collection in the peripancreatic area, and gastric and splenic infarctions associated with multiple thromboses of the short gastric and splenic arteries. She received a total gastrectomy with a Roux-en-Y esophagojejunostomy and a splenectomy. At the follow-up examination, no symptoms were noted. This article is protected by copyright. All rights reserved.