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Background Computed tomography (CT) or MR images may cause the severity of early acute pancreatitis (AP) to be underestimated. As an innovative image analysis method, radiomics may have potential clinical value in early prediction of AP severity. Purpose To develop a contrast-enhanced (CE) MRI-based radiomics model for the early prediction of AP severity. Study type Retrospective. Subjects A total of 259 early AP patients were divided into two cohorts, a training cohort (99 nonsevere, 81 severe), and a validation cohort (43 nonsevere, 36 severe). Field strength/sequence 3.0T, T1 -weighted CE-MRI. Assessment Radiomics features were extracted from the portal venous-phase images. The "Boruta" algorithm was used for feature selection and a support vector machine model was established with optimal features. The MR severity index (MRSI), the Acute Physiology and Chronic Health Evaluation (APACHE) II, and the bedside index for severity in acute pancreatitis (BISAP) were calculated to predict the severity of AP. Statistical tests Independent t-test, Mann-Whitney U-test, chi-square test, Fisher's exact tests, Boruta algorithm, receiver operating characteristic analysis, DeLong test. Results Eleven potential features were chosen to develop the radiomics model. In the training cohort, the area under the curve (AUC) of the radiomics model, APACHE II, BISAP, and MRSI were 0.917, 0.750, 0.744, and 0.749, and the P value of AUC comparisons between the radiomics model and scoring systems were all less than 0.001. In the validation cohort, the AUC of the radiomics model, APACHE II, BISAP, and MRSI were 0.848, 0.725, 0.708, and 0.719, respectively, and the P value of AUC comparisons were 0.96 (radiomics vs. APACHE II), 0.40 (radiomics vs. BISAP), and 0.46 (radiomics vs. MRSI). Data conclusion The radiomics model had good performance in the early prediction of AP severity. Level of evidence 3 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:397-406.

Aim To determine whether diameters of the left gastric vein (LGV) and its originating vein are associated with endoscopic grades of esophageal varices. Methods Ninety-eight liver cirrhotic patients with hepatitis B undergoing magnetic resonance (MR) portography, and upper gastrointestinal endoscopy for grading esophageal varices were enrolled. Diameters of the LGV and its originating vein – the splenic vein (SV) or portal vein (PV) – were measured on MR imaging. Statistical analyses were performed to identify the association of the diameters with the endoscopic grades. Results Univariate analysis showed that the SV was predominantly the originating vein of the LGV, and diameters of the LGV and SV were associated with grades of esophageal varices. Diameters of the LGV (P = 0.023, odds ratio [OR] = 1.583) and SV (P = 0.012, OR = 2.126) were independent risk factors of presence of the varices. Cut-off LGV diameters of 5.1 mm, 5.9 mm, 6.6 mm, 7.1 mm, 7.8 mm and 5.8 mm; or cut-off SV diameters of 7.3 mm, 7.9 mm, 8.4 mm, 9.5 mm, 10.7 mm and 8.3 mm, could discriminate grades 0 from 1, 0 from 2, 0 from 3, 1 from 3, 2 from 3, and 0–1 from 2–3, respectively. Conclusion Diameters of the LGV and SV are associated with endoscopic grades of esophageal varices.

Purpose To study liver imaging with volume acceleration-flexible (LAVA-Flex) for abdominal magnetic resonance imaging (MRI) at 3.0 T and compare the image quality of abdominal organs between LAVA-Flex and fast spoiled gradient-recalled (FSPGR) T1-weighted imaging. Materials and Methods Our Institutional Review Board approval was obtained in this retrospective study. Sixty-nine subjects had both FSPGR and LAVA-Flex sequences. Two radiologists independently scored the acquisitions for image quality, fat suppression quality, and artifacts and the values obtained were compared with the Wilcoxon signed rank test. According to the signal intensity (SI) measurements, the uniformity of fat suppression, the contrast between muscle and fat and normal liver and liver lesions were compared by the paired t-test. The liver and spleen SI on the fat-only phase were analyzed in the fatty liver patients. Results Compared with FSPGR imaging, LAVA-Flex images had better and more homogenous fat suppression and lower susceptibility artifact (qualitative scores: 4.70 vs. 4.00, 4.86% vs. 7.14%, 4.60 and 4.10, respectively). The contrast between muscle and fat and between the liver and pathologic lesions was significantly improved on the LAVA-Flex sequence. The contrast value of the fatty liver and spleen was higher than that of the liver and spleen. Conclusion The LAVA-Flex sequence offers superior and more homogenous fat suppression of the abdomen than does the FSPGR sequence. The fat-only phase can be a simple and effective method of assessing fatty liver. J. Magn. Reson. Imaging 2014;40:58–66. © 2013 Wiley Periodicals, Inc.

Purpose To determine whether dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) could monitor progression of liver fibrosis in a piglet model, and which DCE-MRI parameter is most accurate for staging this disease. Materials and Methods Sixteen piglets were prospectively used to model liver fibrosis and underwent liver DCE-MRI followed by biopsy on the 0, 5th, 9th, 16th, and 21st weekends after modeling of fibrosis. Time of peak (TOP), time to peak (TTP), positive enhancement integral (PEI), maximum slope of increase (MSI), and maximum slope of decrease (MSD) were measured and statistically analyzed for the monitoring and staging. Results As fibrosis progresses, TOP and TTP tended to increase, whereas MSI, MSD, and PEI tended to decrease (all P < 0.05). TOP, TTP, and MSI could discriminate fibrosis stage 0 from 1–4, 0–1 from 2–4, 0–2 from 3–4, and 0–3 from 4; PEI could distinguish the above-mentioned stages except 0–3 from 4; and MSD could distinguish stage 0–3 from 4, and 0 from 1–4 (all P < 0.05). For predicting stage ≥1, ≥2, and ≥3, the area under receiver operating characteristic curve (AUC) of MSI was largest among all parameters; for stage 4 AUC of TTP was largest. Conclusion DCE-MRI has the potential to dynamically stage progression of liver fibrosis. J. Magn. Reson. Imaging 2014;39:872–878. © 2013 Wiley Periodicals, Inc.

Aim To determine whether spleen diffusion-weighted imaging (DWI) parameters might classify liver fibrosis stage. Methods Sixteen miniature pigs were prospectively used to model liver fibrosis, and underwent spleen DWI by using b = 300, 500 and 800 s/mm2 on 0, 5th, 9th, 16th and 21st weekend after the beginning of modeling. Signal intensity ratio of spleen to paraspinous muscles (S/M), spleen exponential apparent diffusion coefficient (eADC) and apparent diffusion coefficient (ADC) for each b-value were statistically analyzed. Results With increasing stages of fibrosis, S/M for all b-values showed a downward trend; and spleen eADC and ADC for b = 300 s/mm2 showed downward and upward trends, respectively (all P

Purpose: To investigate whether and how spleen size measured on magnetic resonance imaging (MRI) could be used to stage liver fibrosis. Materials and Methods: Sixteen minipigs were used to prospectively model liver fibrosis staged by biopsy. Abdominal gadolinium-enhanced MRI was performed on the 0, 5th, 9th, 16th, and 21st weekend after beginning of the modeling. Splenic maximal width (W), thickness (T), length (L), and area (S) together with spleen volume (SV) and liver volume (LV) were measured on enhanced MRI and the ratio of SV to LV (SV/LV) was calculated. Spleen multidimensional indexes 1 and 2 were obtained by W × T × L and S × L, respectively. Statistical analyses were performed to determine which parameter could best stage the fibrosis. Results: W, T, L, S, SV, index 1 and 2, and SV/LV tended to increase with increasing stages of fibrosis (r = 0.46–0.796, all P < 0.001), and might predict liver fibrosis stage ≥1, ≥2, ≥3, and 4 (area under receiver operating characteristic curve [AUC] = 0.697–1.0, all P < 0.05). Among the parameters, splenic index 1, SV, and SV/LV might be best for predicting stage ≥1 (AUC = 0.941), ≥2 or ≥3 (AUC = 0.875 or 0.978, respectively), and 4 (AUC = 1.0), respectively. Conclusion: Spleen size measured on MRI could be used for staging liver fibrosis. J. Magn. Reson. Imaging 2013;38:540–547. © 2013 Wiley Periodicals, Inc.

OBJECTIVE: To determine the features that differentiate earthquake-related crush extremity fractures from non-earthquake-related extremity fractures by using digital radiography (DR) and multidetector row computed tomography (MDCT). METHODS: Six hundred and twenty-three consecutive victims with crush extremity fractures arising from the 2008 Sichuan earthquake, including 611 undergoing DR and 12 undergoing MDCT, entered the test group, and 316 consecutive victims with non-earthquake-related extremity fractures, including 301 undergoing DR and 15 undergoing MDCT, were enrolled in the control group. Image data were reviewed retrospectively and statistically between groups focusing on the anatomic distributions, numbers and types of extremity fractures. RESULTS: Fractures involving multiple extremities were more likely in the test group than the control group (88/623 vs 27/316 victims, P Language: en