• Mathilde Wagner, Sabrina Doblas, Nicolas Poté, Simon A Lambert, Maxime Ronot, Philippe Garteiser, Valérie Paradis, Valérie Vilgrain, and Bernard E Van Beers.
• Laboratory of Imaging Biomarkers, Center for Research on Inflammation, UMR 1149, Inserm - University of Paris, Paris, France.
• J Magn Reson Imaging. 2020 Apr 1; 51 (4): 1065-1074.

BackgroundIn contrast to classical pulsed gradient diffusion-weighted MRI, oscillating gradient diffusion-weighted MR imaging (DWI) is sensitive to short distance diffusion changes at the intracellular level.PurposeTo compare the diagnostic performance of pulsed and oscillating DWI for characterizing hepatocellular nodules in a rat model of hepatic cirrhosis.Study TypeProspective, experimental study.Animal ModelCirrhosis was induced by weekly intraperitoneal injection of diethylnitrosamine in Wistar rats.Field Strength/SequenceEx vivo liver MRI was performed at 7T with T1 -weighted, T2 -weighted, pulsed, and oscillating gradient diffusion-weighted sequences.AssessmentApparent diffusion coefficient from pulsed (ADCpulsed ) and oscillating gradient (ADCoscillating ) sequences was calculated in 82 nodules identified on the T1 /T2 -weighted images and on pathological examination. Two pathologists classified the nodules in three categories: benign (regenerative and low-grade dysplastic nodules), with intermediate malignancy (high-grade dysplastic nodules and early hepatocellular carcinomas) and overtly malignant (progressed hepatocellular carcinomas).Statistical TestsDifferences between groups were assessed with Kruskal-Wallis and Mann-Whitney tests.ResultsADC, mainly ADCoscillating , increased in the group of nodules with intermediate malignancy (ADCpulsed : 0.75 ± 0.25 × 10-3 mm2 /s vs. 0.64 ± 0.07 × 10-3 mm2 /s in benign nodules, P = 0.025; ADCoscillating : 0.81 ± 0.20 × 10-3 mm2 /s vs. 0.65 ± 0.13 × 10-3 mm2 /s, P = 0.0008) and ADCpulsed decreased in the group of progressed hepatocellular carcinomas (ADCpulsed : 0.60 ± 0.08 × 10-3 mm2 /s, P = 0.042; ADCoscillating : 0.68 ± 0.08 × 10-3 mm2 /s, P = 0.1).Data ConclusionADC during hepatocarcinogenesis in rats increased in nodules with intermediate malignancy and decreased in progressed hepatocellular carcinomas. Our results suggest that oscillating gradient DWI is more sensitive to the early steps of hepatocarcinogenesis and might be useful for differentiating between high-grade dysplastic nodules / early hepatocellular carcinomas and regenerating nodules / low-grade dysplastic nodules.Level Of Evidence2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2020;51:1065-1074.© 2019 International Society for Magnetic Resonance in Medicine.

16 keywords...

hide…