ObjectiveTo evaluate the effect of early anticoagulation therapy in the prevention of portal venous system thrombosis (PVT) in portal hypertensive patients undergoing splenectomy plus portaazygous devascularization. MethodsAt our hospital from August 1994 to July 2011,157 patients underwent splenectomy plus devascularization. Among them 89 cases (beginning 2000 )receiving intravenous low molecular dextran 500 ml daily for 7 days starting immediately postoperatively,and after 48 h subcutaneously low molecular weight heparin calcium 4250 U every 12 hours for 7 - 14 d were in group A.Before 2000,the 68 cases receiving no postoperative anticoagulation therapy were in the control group (B).After 3 - 12 months follow-up,PVT was evaluated and compared between the two groups. ResultsIn group A thrombosis incidence was 8％ (7/89),of which class Ⅰ, Ⅱ thrombosis accounted for 71％(5/7),class Ⅲ and up thrombosis accounted for 29％ (2/7),there was no bowel necrosis case; In group B thrombosis incidence was 29％ (20/68),class Ⅰ,Ⅱ thrombosis accounted for 20％ (4/20),class Ⅲand above thrombosis accounted for 80％ (16/20),3 cases suffered from intestinal necrosis,the difference was statistically significant (P ＜ 0.01 ). ConclusionsMultifactors lead to postoperative PVT formation,early postoperative,anticoagulation therapy is safe,and effective in the prevention of postoperative PVT.

Objective To investigate the imaging features in CT/MR of pancreatic neuroendocrine tumors(PNETs) with multiple lesions and further deepen the understanding of this disease .Methods A retrospective review of 12 PNETs patients′radiological data with pancreatic tumors′numbers≥2 and confirmed by surgery or fine needle aspiration biopsy in Changhai Hospital were conducted .Five cases underwent pancreatic CT plain and enhanced scan , 2 cases underwent MRI plain and enhanced scan , and 5 cases underwent both CT and MRI scan .Results There were totally 46 lesions in 12 patients.There were 29 (63.0%) lesions located in the pancreatic head and neck , and 17(37.0%) lesions located in body and tail of pancreas.The sizes of the lesions ranged from 0.8 to 9.5 cm,and the median size was 2.9 cm.Forty-four (95.7%) of the tumors was round or oval , and 2 ( 4.3%) was lobulated;44 ( 95.7%) mass solid and 2 (4.3%) was cystic.CT plain scan detected punctate , crescent or nodular calcification in 8(17.4%) lesions;enhanced scan found 42 lesions(91.4%) were markedly enhanced in the arterial phase , 2 lesions (4.3%) were markedly enhanced in the pancreatic phase;2 lesions (4.3%) were slightly enhanced and the degree of enhancement was lower than that of the normal pancreas .Four cases (33.3%) had dilatation of pancreatic duct and/or the bile duct, 4 cases (33.3%) had distant organ metastasis, 2 cases (16.7%) had lymph node metastasis, and 3 cases (25.0%) had vascular invasion .Conclusions PNETs can be multiple and vary in the size.Most of the lesions are round or oval solid lesions and the malignant signs for organ metastasis can be found occasionally .In dynamic enhanced scanning , the obvious enhancement of the solid portion in the tumor and the higher enhancement degree than that of normal pancreas is the main characteristic .

Objective To explore the CT findings of benign and malignant pancreatic neuroendocrine tumors and improve its diagnostic accuracy.Methods The clinical information and enhanced CT findings of 96 cases with pathologically-proved pancreatic neuroendocrine tumors were retrospectively reviewed.The CT findings were evaluated by several factors,which included tumor size,morphology,location,internal composition,calcification,separation,bile duct and pancreatic duct dilation and CT value.Results All cases were divided into benign or malignant according to pathological grades,and benign group involved 40 cases with 41 lesions,while malignant group involved 56 cases with 59 lesions.The size of malignant lesions was significantly larger than that of benign lesions (median size 6.0 cm vs 2.2 cm),the shape of the lesions was irregular,and was mainly cystic solid,and mottling,curve shape,clumps calcification was present,then the bile duct and pancreatic duct was mild to moderately dilated,and the difference between the two groups was statistically significant (P ＜0.05).But the difference of tumor location,separation was not significant.45.76％ (27/59) of the malignant lesions reached the peak value in arterial phase,and 44.07％ (26/59) reached the peak value in venous phase;while 68.29％ (28/41) of the benign lesions reached the peak value in arterial phase,and 31.71％ (13/41) reached the peak value in venous phase.The CT values of malignant lesions in plain CT scanning,arterial phase,venous phase,balance phase were (39.02 ±7.53),(121.20 ± 54.73),(125.25 ± 40.77),(101.41 ± 28.68) Hu,while they were (41.49 ± 8.59),(144.73 ± 53.95),(157.05 ±44.72),(121.02 ±29.80) Hu in benign group.In plain CT scanning,the difference of CT value between malignant and benign lesions was not significant;but in the enhanced phase,the CT value of malignant lesions was significantly lower than that of benign lesions,and the difference was statistically significant (P ＜ 0.05).Conclusions The lesion with its size ≥ 3.0 cm,irregnlar morphology,cystic necrosis,calcification,pancreatic and bile duct dilatation is suggestive of malignancy tumor.The average CT values of malignant group are lower than those of the benign group in arterial,venous and balance phases.

Objective To study the potential and value of ultrasmall superparamagnetic iron oxide (USPIO) conjugated by mesothelin antibody as MRI targeting contrast agent for diagnosis of implanted human pancreatic carcinomas in nude mouse.Methods Nude mouse tumor models bearing multiple human pancreatic carcinomas at different time points was established and they were randomized into two groups,and USPIO or MSLN-USPIO were used as contrast enhanced agents in the 3.0T MRI scan,respectively,then the positive detection rates for smallest tumors,and the signal intensity of tumors in T2 mapping images of both unenhanced and contrast enhanced scanning and the negative enhancement rate were measured,then Prussian blue staining was performed in alI the tumor specimens to observe the difference of Fe3 + ion deposition.Results There was no statistical significance between USPIO group and MSLN-USPIO group in the positive detection rates for smallest tumors.In USPIO group,the negative enhancement rate of left or right axilla tumors was (12.29 ±7.45)％ and (11.06 ±5.91)％,and they were (33.88 ±6.09)％ and (43.29 ± 11.64)％ in MSLN-USPIO group.There was statistical significance in the difference of signal intensity between unenhanced and contrast enhanced in left or right axilla tumors (P ＜ 0.05),and the negative enhancement rate in MSLN-USPIO group was significantly higher than that in USPIO group (P ＜0.05).The Fe3+ ion deposition in tumors' tissue in MSLN-USPIO group was significantly more than that in USPIO group.Conclusions The enhanced effect of MSLN-USPIO is superior to USOPIO,and it can be a tumor targeted MR contrast enhanced agent for the diagnosis of pancreatic carcinoma in nude mouse.

Objective To investigate the feasibility of establishing a digital model of juxtahepatic vena cava.Methods The clinical data of 120 participants (without liver diseases) who were admitted to the Cangzhou Central Hospital from January 2013 to May 2013 were collected.The results of computed tomography were analyzed.The diameters of juxtahepatic vena cava on different levels (P1 plane:inferior vena cava at the entrance to the right atrium,P2 plane:the upper margin of the roots of hepatic veins,P4 plane:lower boundary of liver,P5 plane:confluence of renal veins and inferior vena cava),and the circumference of the inferior vena cava and the lengths between these levels were recorded.A digital model of juxtahepatic vena cava was established by these data on the premise that the juxtahepatic vena cava was engorged.All data were analyzed using the analysis of variance,paired sample t test and independent samples t test,and correlation and regression were used in analysis of relations between there data.Results Data of the P1 plane and P2 plane were both missed in 3 cases,and the data of the P4 plane was missed in 8 cases.The theoretical diameter of hepatic vena cava at the P1,P2 and P4 planes were (28.1 ± 4.0) mm,(28.7 ± 3.5) mm and (23.5 ± 2.7) mm,respectively.The median diameter of hepatic vena cava at the P5 plane was 24.3 mm.The juxtahepatic vena cava was a 3 dimensional structure of cylinder with a slightly protruding middle part.There were significant differences in P1D-P2D,P2D-P4D,P1D-P4D (F =77.5,P ＜ 0.05).There were significant differences between P2D-P4D and P1D-P4D (t =14.893,11.210,P ＜ 0.05).The median length of hepatic vena cava between P1 and P2 planes was 7.5 mm.The lengths of hepatic vena cava between P1 and P4 planes,P2 and P4 planes were (85.2 ± 11.0)mm and (78.2 ±9.8)mm,respectively.The median length of hepatic vena cava between the P4 and P5 planes was 10.0 mm.P1D-P2D,P2D-P4D,P2D-P5D and P4D-P5D were positively correlated (r =0.862,0.308,0.186,0.788,P ＜ 0.05),while P1D-P4D and P2D-P5D did not correlated (r =0.180,0.118,P ＞0.05).P2D was correlated with the body weight,and P5 D was correlated with the age (r =0.200,0.130,P ＜ 0.05).The P1 D,P2D,P4D and P5 D of the inferior vena cava were (28.5 ± 3.7) mm,(29.0 ± 3.4) mm,(23.9 ± 2.8) mm and (24.3 ± 2.6) mm in males,and (27.8 ±4.2) mm,(28.5 ± 3.6) mm,(23.1 ± 2.5) mm and 24.0 mm in females.There were no significant difference in P1D,P2D,P4D and P5D between males and females (t =0.911,0.809,1.588,1.902,P ＞ 0.05).The length between P1 and P2 planes was negatively correlated with P1D and P2D (r =-0.245,-0.160,P ＜ 0.05),while the length between P4 and P5 planes was positively correlated with P1D (r =0.149,P ＜ 0.05).The length between P2 and P4 planes was positively correlated with P2D (r =0.195,P ＜ 0.05).The length between P1 and P2 planes did not correlated with the age,height and body weight (r =-0.092,-0.047,-0.033,P ＞ 0.05).The lengths between P2 and P4 planes,P1 and P4 planes were negatively correlated with the age (r =-0.343,-0.371,P ＜ 0.05),but positively correlated with the body weight (r =0.271,0.208,P ＜ 0.05).The length between P4 and P5 planes was positively correlated with the height and body weight (r =0.154,0.255,P ＜ 0.05).There were no significant difference in the lengths between P1 and P2 planes,P1 and P4 planes,P2 and P4 planes,P4 and P5 planes between males and females (t =-1.046,-1.274,-0.908,1.375,P ＞ O.05).The length between P2 and P4 planes was similar to the length of retrohepatic vena cava.The length between P2 and P4 planes(mm) =71.23-0.293 × age (years) +0.32 × body weight (kilogram).Conclusion The establishment of digital model of juxtahepatic vena cava based on the computed tomography imaging data is feasible,which provides basis for clinical investigation.

Objective To investigate the causes and prevention measures for patients with portal hypertension hypersplenism undergone splenectomy plus pericardial devascularization and post-operative portal vein thrombosis (portal vein thrombogenesis,PVT).Methods 178 cases of splenectomy plus devascularization from July 2013 to May 1994 in Cangzhou Central Hospital of Hebei Province,including 102 cases of early postoperative application of low molecular heparin anticoagulant for the prevention group,76 cases without anticoagulant medicine as control group.33 cases with PVT found by B ultrasound or CT scan,were treated with urokinase body intravenous thrombolysis,hepatic artery catheterization thrombolysis,intestinal resection of + Fogarty catheter embolectomy vein stump treatment respectively.Results The total incidence of thrombosis was 18.5％ (33/178),prevention group was 8.8％ (9/102),including 7 cases in grade Ⅰ,Ⅲ,Ⅳ thrombus,in 1 cases,no intestine necrosis.The control group thrombosis rate was 31.6％ (24/76),including 7 cases in grade Ⅰ,Ⅲ,Ⅳ,thrombosis in 17 cases,5 cases of intestine necrosis,two groups of thrombosis rate were significantly differences (x2 =14.932,P =0.000).Thrombus disappeared completely in 7 cases,the thrombus grading decreased in 2 cases in the preventive group after thrombolysis,and thrombus disappeared completely in 6 cases,11 cases of thrombosis degraded in the control group after treatment of thrombolysis,1 case cured by TIPS with thrombolysis and thrombectomy,1 case died of sudden digestive tract bleeding,Among 5 cases of intestinal necrosis,4 cases died and 1 case undergone abdominal exploration being found with intestine & colon necrosis.Conclusions There are a variety of factors causing PVT after splenectomy and devascularization.Early anticoagulation can significantly reduce the incidence of PVT,early discovery and treatment can prevent severe outcome.

Objective To explore the effect of early anticoagulation therapy on the blood coagulation in patients undergoing splenectomy plus devascularization.Methods Clinical data of 106 patients in Cangzhou Central Hospital from June 2000 to December 2012 were reviewed.Beginning 24 h after surgery,low molecular dextran 500 ml + ligustrazine 160 mg,once a day for 1 week,and after 48 h low molecular heparin calcium at 4 250 U to 4 500 U was given every 12 h for 7 to 14 d.Blood coagulation was tested on day 3,5,7,10 and 14,ultrasound 1-2 times a week was taken for detection of portal venous thrombosis.Results The incidence of portal thrombosis was 7.5％ (8/106).APTT prolonged during 7-14 d.Prothrombin time (PT),thrombin time (TT) and fibrinogen (FIB) decreased,but all the changes were not statistically significant when compared with the normal values(P ＞0.05).Anticoagulant treatment did not cause bleeding complications in this series.Conclusions Postoperative application of low molecular heparin calcium anticoagulant therapy is effective in the prevention of portal thrombosis and safe in terms of coagulation when started early in patients undergoing splenectomy.

Objective:To summarize the MRI features of intrapancreatic accessory spleen (IPAS) and G1 grade pancreatic neuroendocrine neoplasms (PNENs), and clarify the radiological features for differential diagnosis.Methods:The data of 11 patients with IPAS confirmed by surgical pathology or 99mTc thermal denatured red blood cell imaging and 9 patients with G1 grade PNENs confirmed by surgical pathology in the tail of pancreas from January 2013 to December 2019 admitted in First Affiliated Hospital of Navy Medical University were retrospectively analyzed. MRI features of IPAS group and PNENs group, including shape, size, whether it protruded beyond the contour of the pancreas, cystic degeneration, plain scan of T 2WI, DWI signal, multistage enhancement mode, false capsule, etc. were studied and compared. Results:There was significantly statistical difference between the two groups in the terms of contour protrusion, T 2WI and DWI signals, multistage enhancement, and pseudomembrane (all P< 0.05). Protruded lesion was more common in the PNENs group (9/9 cases) than in the IPAS group (3/11). The T 2WI and DWI signals of lesions in the PNENs group were slightly higher than those in the IPAS group, and the proportion of high T 2WI and DWI signal lesions in the PNENs group was 6/9 cases and 4/9 cases, respectively, while the proportion of high T 2WI and DWI signal lesions in the IPAS group was 0/11 cases. Multistage enhancement of lesions in the PNENs group was more likely to be consistent (6/9), while lesions in the IPAS group were more inconsistent (10/11). In the PNENs group, all lesions showed false envelope after enhancement (9/9), while in the IPAS group, no false envelope was observed after enhancement (0/11). Conclusions:The presence of protruded lesions, the characteristics of T 2WI and DWI signals, the mode of multiphase enhancement and the false envelope were essential signs for differentiating IPAS and G1 grade PNENs.

Objective:To analyze the MRI findings of solid pseudopapilloma of the pancreas (SPTs) and nonfunctional pancreatic neuroendocrine tumors (PNETs), and to establish and verify the prediction model of SPTs and PNETs.Methods:The clinical and MRI data of 142 patients with SPTs and 137 patients with PNETs who underwent surgical resection and were confirmed by pathology in the First Affiliated Hospital of Naval Medical University from January 2013 to December 2020 were collected continuously. Age, gender, body mass index (BMI), lesion size, location, shape, boundary, cystic change, T 1WI signal, T 2WI signal, enhancement peak phase, whether the enhancement degree was higher than that of pancreatic parenchyma in the enhancement peak phase, enhancement pattern, whether pancreatic duct and common bile duct were dilated, whether the pancreas shrank, and whether it invaded adjacent organs and vessels were recorded. According to the international consensus on prediction model modeling, patients were divided into training set (106 SPTs and 100 PNETs between January 2013 and December 2018), and validation set (36 SPTs and 37 PNETs between January 2019 and December 2020). The above characteristics of patients in training and validation set were analyzed by univariate and multivariate logistic regression, and a prediction model was established to distinguish SPTs and PNETs, and then visualized as a nomogram. The receiver operating characteristic curve (ROC) of the nomogram of training set and verification set was drawn, and the area under the curve (AUC), sensitivity, specificity and accuracy were calculated to evaluate the prediction efficiency of the model, and the clinical application value of the prediction model was evaluated by decision curve analysis (DCA). Results:Univariate regression analysis showed that there were significant differences on age, gender, lesion size, shape, cystic change, T 1WI signal, peak phase of enhancement, degree of enhancement in peak phase, pattern of enhancement and invasion of adjacent organs between SPTs group and PNETs group (all P value <0.05). Multivariate regression analysis showed that the older age, male patients, the smaller lesion, no high signal on T 1WI, the enhancement peak phase located in arterial phase or venous phase, and the enhancement degree in peak phase higher than that of pancreatic parenchyma were the six independent predictors of PNETs. The prediction model was established by using these six factors and visualized as a nomogram. The formula for predicting PNETs probability was 4.31+ 1.13×age+ 1.31×tumor size-1.29×female-4.18×high T 1WI signal+ 1.28×the enhancement degree higher than that of pancreatic parenchyma -4.69 ×enhancement peak in delay phase. The prediction model was visualized as a nomogram. The AUC values in the training set and validation set were 0.99(95% CI0.977-1.000) and 0.97 (95% CI 0.926-1.000), respectively. The sensitivity, specificity and accuracy in the training set are 98.00%, 94.34% and 96.12% and in the validation set were 86.49%, 97.22% and 91.78% respectively. The results of decision curve analysis show that the prediction model can accurately diagnose SPTs and PNETs. Conclusions:The prediction model established in this study can accurately differentiate SPTs from PNETs, and can provide important information for clinical decision and prognosis.

Objective:To investigate the MRI features of intraductal papillary mucinous tumor (IPMN) of the pancreas and establish a prediction model for predicting the malignancy risk.Methods:The clinical data of 260 IPMN patients who underwent MRI and pathological confirmed in the First Affiliated Hospital of Naval Medical University from October 2012 to April 2020 were retrospectively analyzed. According to the pathological results, all patients were divided into benign group (including IPMN with low-grade dysplasia) and malignant group (including IPMN with high grade dysplasia and invasive carcinoma). According to international consensus of prediction model modeling, patients were divided into training set and validation set in chronological order. A prediction model was developed based on a training set consisting of 193 patients (including 117 patients with benign IPMN and 76 patients with malignant IPMN) between October 2012 and April 2019, and the model was validated in 67 patients (including 40 patients with benign IPMN and 27 patients with malignant IPMN) between May 2019 and April 2020. The multivariable logistic regression model was adopted to identify the independent predictive factors for IPMN malignancy and establish and visualized a nomogram. The ROC was drawn and AUC was calculated. The decision curve analysis was used to evaluate its clinical usefulness.Results:The IPMN type, cyst size, thickened cyst wall, mural nodule size, diameter of main pancreatic duct (MPD) and the abrupt change in the caliber of the MPD with distal pancreatic atrophy in the training set and validation set, and jaundice and lymphadenopathy in the training set were significantly different between benign group and malignant group ( P<0.05). The multivariable logistic regression model of characteristics included the jaundice, cyst size, mural nodule size ≥5 mm, the abrupt change in caliber of the MPD with distal pancreatic atrophy were independent risk factors for IPMN maligancy. The model for predicting IPMN malignancy was -0.35+ 2.28×(jaundice)+ 1.57×(mural nodule size ≥5 mm)+ 2.92×(the abrupt change in caliber of the MPD with distal pancreatic atrophy)-1.95×(cyst <3 cm)-1.05×(cyst≥3 cm). The individualized prediction nomogram using these predictors of the malignant IPMN achieved an AUC of 0.85 (95% CI 0.79-0.91) in the training set and 0.84 (95% CI 0.74-0.94) in the validation set. The sensitivity, specificity and accuracy of the training set were 72.37%, 85.47% and 80.31%, respectively. The sensitivity, specificity and accuracy of the validation set were 81.48%, 75.00% and 77.61%, respectively. The decision curve analysis demonstrated that when the IPMN malignancy rate was >0.16, the nomogram diagnosing IPMN could benefit patients more than the strategy of considering all the patients as malignancy or non-malignancy. Conclusions:The nomogram based on MRI features can accurately predict the risk of malignant IPMN, and can be used as an effective predictive tool to provide more accurate information for personalized diagnosis and treatment of patients.