Objective:To explore the value of proton density fat fraction(PDFF) based on histogram analysis for quantification hepatic steatosis and fibrosis in rabbit model and the interference of hepatic fibrosis to the evaluation of hepatic steatosis with PDFF.Methods:From March to November 2020, 135 New Zealand white rabbits were randomly divided into control group ( n=30) and experimental group ( n=105) using a random number table. The volume ratio of CCl 4 and olive oil was 1∶1 to prepare 50% CCl 4 oil solution, and experimental rabbits were subcutaneously injected with the oil solution. An equal dose of normal saline was subcutaneously injected for control group rabbits. At the end of the 4 th, 8 th, and 12 th week, 35 in the experimental group and 10 rabbits in the control group were randomly selected to conduct the mDixon-Quant scanning, and histogram analysis of PDFF was analyzed including volume, mean, median, standard deviation, 25 th, 50 th, 75 th, 90 th quantile, skewness, kurtosis, entropy and inhomogeneity. After the examination, the rabbits were sacrificed and the liver percentage of steatosis (PSH) and fibrosis (POF) were recorded by semi-quantitative analysis. Spearman correlation analysis was used to correlate PDFF with PSH and POF. Multiple linear regression analysis was used to determine independent PDFF histogram parameters for evaluating PSH and POF. A receiver operator characteristic (ROC) curve was used to assess the diagnostic accuracy of PDFF for discriminating mild from moderate-severe hepatic steatosis and mild from moderate-severe hepatic fibrosis with median of PSH or POF for dichotomy, and DeLong test was used to compare the area under the curve (AUC). With the correction of hepatic fibrosis, correlation coefficient and AUC were compared of PDFF for discrimination mild from moderate-severe hepatic steatosis. Results:The PDFF mean, median, standard deviation, 75 th, 90 th showed correlation with PSH ( r=0.558, 0.522, 0.319, 0.723, 0.646, -0.589, all P<0.05). The entropy and 75 th were independent parameters for evaluating PSH (β=2.347, -5.960, P=0.018, 0.001). The PDFF 75 th was the optimal parameter for discriminating mild from moderate-severe hepatic steatosis with AUC=0.915 ( P=0.001). The PDFF volume, mean, median, standard deviation, 75 th, 90 th, entropy showed correlation with POF ( r=0.355, 0.393, 0.376, 0.298, 0.485, 0.426, -0.681, all P<0.05). The entropy, standard deviation and volume (β=-11.041, 1.356, 0.190, P=0.001, 0.026, 0.016) were independent parameters for evaluation of hepatic fibrosis, and the entropy was the optimal parameter for hepatic fibrosis (AUC=0.771, P=0.001). The correlation between PSH and PDFF 75 th was less pronounced when fibrosis was present ( r=0.512, P=0.001) than when fibrosis was absent ( r=0.751, P=0.002). The PDFF 75 th showed a significant difference in discriminating mild hepatic steatosis from moderate-severe hepatic steatosis after correction of POF (AUC=0.895, 0.950, Z=2.970, P=0.025). Conclusions:PDFF based on histogram analysis provided a noninvasive, accurate estimation of quantification for hepatic steatosis and fibrosis. Hepatic fibrosis reduced the correlation between hepatic steatosis and PDFF and the presence of hepatic fibrosis can confound the quantification of hepatic steatosis with PDFF.

Objective:To establish and verify a nomogram model based on MRI liver imaging reporting and data system (LI-RADS) features for predicting microvascular invasion (MVI) in hepatocellular carcinoma (HCC) following the Milan criteria.Methods:A retrospective analysis was conducted on data from 118 HCC patients (121 lesions) confirmed by pathology from June 2016 to June 2022 at the Third Affiliated Hospital of Soochow University. Forty-seven HCCs were diagnosed as MVI-positive and 74 HCCs as MVI-negative. The data was randomly divided into the training set (83 patients with 84 HCCs, including 31 MVI-positive and 53 MVI-negative HCCs) and the test set (35 patients with 37 HCCs, including 16 MVI-positive and 21 MVI-negative HCCs) using cross-validation method. HCC imaging features were evaluated based on LI-RADS (version 2018). In the training set, the χ 2 test was used to compare the differences in LI-RADS features between the MVI-positive group and the MVI-negative group. The logistic regression analysis was conducted to identify independent risk factors for predicting MVI-positive and to construct the nomogram model. The receiver operating characteristic (ROC) curves and decision curve analysis (DCA) were used to evaluate the performance and clinical benefits of the nomogram model in predicting MVI tumors. Results:There were statistically significant differences between the MVI-positive group and the MVI-negative group in terms of tumor size, tumor margin, mosaic architecture, and corona enhancement ( P<0.05). Multivariate logistic analysis results showed that HCC maximum diameter>3 cm (OR=1.427, 95%CI 1.314-12.227, P=0.009), nonsmooth tumor margin (OR=3.167, 95%CI 1.227-461.232, P=0.041), mosaic architecture (OR=1.769, 95%CI 1.812-61.434, P=0.022), and corona enhancement (OR=4.015, 95%CI 3.327-836.384, P=0.011) were independent risk factors for predicting MVI-positive tumors. Based on the independent predictors, the constructed nomogram model demonstrated an area under the ROC curve of 0.863 (95%CI 0.768-0.947) and 0.887 (95%CI 0.804-0.987) in the training and test sets for predicting MVI tumors, respectively. DCA showed that the curve of the nomogram model was consistently above the treat-all and treat-none strategies across all reasonable threshold probabilities in the training set, indicating that patients could obtain clinical benefits from the model. Conclusions:The preoperative nomogram model based on MRI LI-RADS features can effectively predict MVI in HCC following the Milan criteria, which could benefit the patients.

Objective: To investigate the diagnosis and treatment for enterocutaneous fistula (ECF) in China, and to explore the prognostic factors of ECF. Methods: A multi-center cross-sectional study was conducted based on the Registration System of Chinese Gastrointestinal Fistula and Intra-Abdominal Infections to collect the clinical data of ECF patients from 54 medical centers in 22 provinces/municipalities from January 1, 2018 to December 31, 2018. The clinical data included patient gender, age, length of hospital stay, intensive care unit (ICU) admission, underlying diseases, primary diseases, direct causes of ECF, location and type of ECF, complications, treatment and outcomes. All medical records were carefully filled in by the attending physicians, and then re-examined by more than two specialists. The diagnosis of ECF was based on the clinical manifestations, laboratory/imaging findings and intraoperative exploration. Results: A total of 1521 patients with ECF were enrolled, including 1099 males and 422 females, with a median age of 55 years. The top three primary diseases of ECF were malignant tumors in 626 cases (41.2%, including 540 gastrointestinal tumors, accounting for 86.3% of malignant tumors), gastrointestinal ulcers and perforations in 202 cases (13.3%), and trauma in 157 cases (10.3%). The direct causes of ECF were mainly surgical operation in 1194 cases (78.5%), followed by trauma in 156 (10.3%), spontaneous fistula due to Crohn′s disease in 92 (6.0%), radiation intestinal injury in 41 (2.7%), severe pancreatitis in 20 (1.3%), endoscopic treatment in 13 (0.9%) and 5 cases (0.3%) of unknown reasons. All the patients were divided into three groups: 1350 cases (88.7%) with simple ECF, 150 (9.9%) with multiple ECF, and 21 (1.4%) with combined internal fistula. Among the patients with simple ECF, 438 cases (28.8%) were jejuno-ileal fistula, 313 (20.6%) colon fistula, 170 (11.2%) rectal fistula, 111 (7.3%) duodenal fistula, 76 (5.0%) ileocecal fistula, 65 (4.3%) ileocolic anastomotic fistula, 55 (3.6%) duodenal stump fistula, 36 (2.4%) gastrointestinal anastomotic fistula, 36 (2.4%) esophagogastric/esophagojejunal anastomotic fistula, 29 (1.9%) gastric fistula and 21 (1.4%) cholangiopancreatiointestinal. Among all the simple ECF patients, 991 were tubular fistula and 359 were labial fistula. A total of 1146 patients finished the treatment, of whom 1061 (92.6%) were healed (586 by surgery and 475 self-healing) and 85 (7.4%) died. A total of 1043 patients (91.0%) received nutritional support therapy, and 77 (6.7%) received fistuloclysis. Infectious source control procedures were applied to 1042 patients, including 711 (62.0%) with active lavage and drainage and 331 (28.9%) with passive drainage. Among them, 841 patients (73.4%) underwent minimally invasive procedures of infectious source control (replacement of drainage tube through sinus tract, puncture drainage, etc.), 201 (17.5%) underwent laparotomy drainage, while 104 (9.1%) did not undergo any drainage measures. A total of 610 patients (53.2%) received definitive operation, 24 patients died within postoperative 30-day with mortality of 3.9% (24/610), 69 (11.3%) developed surgical site infection (SSI), and 24 (3.9%) had a relapse of fistula. The highest cure rate was achieved in ileocecal fistula (100%), followed by rectal fistula (96.2%, 128/133) and duodenal stump fistula (95.7%,44/46). The highest mortality was found in combined internal fistula (3/12) and no death in ileocecal fistula. Univariate prognostic analysis showed that primary diseases as Crohn′s disease (χ²=6.570, P=0.010) and appendicitis/appendiceal abscess (P=0.012), intestinal fistula combining with internal fistula (χ²=5.460, P=0.019), multiple ECF (χ²=7.135, P=0.008), esophagogastric / esophagojejunal anastomotic fistula (χ²=9.501, P=0.002), ECF at ileocecal junction (P=0.012), non-drainage/passive drainage before the diagnosis of intestinal fistula (χ²=9.688, P=0.008), non-drainage/passive drainage after the diagnosis of intestinal fistula (χ²=9.711, P=0.008), complicating with multiple organ dysfunction syndrome (MODS) (χ²=179.699, P<0.001), sepsis (χ²=211.851, P<0.001), hemorrhage (χ²=85.300, P<0.001), pulmonary infection (χ²=60.096, P<0.001), catheter-associated infection (χ²=10.617, P=0.001) and malnutrition (χ²=21.199, P<0.001) were associated with mortality. Multivariate prognostic analysis cofirmed that sepsis (OR=7.103, 95%CI:3.694-13.657, P<0.001), complicating with MODS (OR=5.018, 95%CI:2.170-11.604, P<0.001), and hemorrhage (OR=4.703, 95%CI: 2.300-9.618, P<0.001) were independent risk factors of the death for ECF patients. Meanwhile, active lavage and drainage after the definite ECF diagnosis was the protective factor (OR=0.223, 95%CI: 0.067-0.745, P=0.015). Conclusions The overall mortality of ECF is still high. Surgical operation is the most common cause of ECF. Complications e.g. sepsis, MODS, hemorrhage, and catheter-associated infection, are the main causes of death. Active lavage and drainage is important to improve the prognosis of ECF.