Objective To evaluate the diagnosis of of hypoplastic vertebral artery by spiral CT angiography(SCTA).Methods 180patients with clinical diagnosis of vertebrobasilar insufficiency were undergone spiral CT angiography. For SCTA, 80~100 ml contrastmedium (omnipaque 350 mg/100 ml) was injected into the foot vein at the rate of 3 ml/s. The delay time was selected through a time-density curve made by Smart prep. Collimation thickness was 3mm and the table speed was 4.5mm/s. Reconstruction was done with 1.5mm increments. The SCTA images were postprossed with multiplanar volume reconstructions (MPVR) and shaded surface display (SSD). Original axial images were used to measure the diameter of vertebral artery. DSA was performed for those cases with vertebral artery stenosis within one week. Results Seventy eight (21.7%) unilateral vertebral arteries were diagnosed as hypoplastic vertebral artery,the left in 24 and the right in 54,the average diameter was 1.3 mm(1.0~1.5 mm),among them,opposite artery coexisted with local calcifications in13 cases, with twist in 20 and with compression by luschka joint hyperplasia in 11. The results were corresponding to that of DSA.Conclusion Hypoplastic vertebral artery is one of the popular reasons of vertebrobasilar artery insufficiency , it could be diagnosed by SCTA and should be used generally in clinic to substitute the more invasive DSA inspection.

Objective To study the diagnostic value of calcification in differentiating benign and malignant thyroid lesions. Methods CT images of 318 consecutive patients with pathologically proven thyroid lesions were retrospectively reviewed by two radiologists. The following characteristics of calcification on CT images were evaluated: (1) size (≤2 mm indicating microcalcification and > 2 mm or shelly and irregular shape indicating macrocalcification, and both features indicating mixed calcification), (2) number (single or multiple) and (3)location (internal or edge). χ~2 test was used for statistical analysis. Results Oft he 318 cases, 48 were diagnosed as malignant (papillary carcinoma 26, follicular carcinoma 7, medullary carcinoma 3 and microcarcinoma 12) and 270 were benign (nodular goiter 36, adenoma 170, nodular goiter with adenoma 38 and adenoma with Hashimoto's thyroiditis 26). Calcification was found in 60 cases (18.9%). Among them 21 (papillary carcinoma 12,microcarcinoma 6,follicular carcinoma 2 and medullary carcinoma 1) were malignant(43.8%) and 39(nodular goiter 6, adenoma 13,nodular goiter with adenoma 19 and adenoma with Hashimoto's thyroiditis 1) were benign (14.4%) (P < 0.01). Sensitivity and specificity for diagnosing thyroid carcinoma were 43.8% (21/48) and 85.6% (231/270), respectively. Microcalcification was found in 37 cases (malignant 8, benign 29) and macrocalcification was found in 23 cases(malignant 13, benign 10) (P < 0.01) . Sensitivity and specificity of macrecalcification for diagnosing thyroid carcinoma were 61.9% (13/21) and 74.4% (29/39), respectively. Single calcification was found in 31 cases (malignant 13, benign 18) and multiple calcification was found in 29 cases(malignant 8, benign 21) (P >0.05). Internal calcification was found in 15 cases of malignant lesions(71.4%) and 12 of benign lesions(30.8%); Edge calcification was found in 6 cases of malignant and 27 of benign, (P <0.01). Sensitivity and specificity of internal calcification for diagnosing thyroid carcinoma were 71.4% (15/21) and 69.2% (27/39), respectively. Conclusion Internal calcification or(and) macrocalcification of the thyroid lesions may strongly suspect thyroid carcinoma and fine-needle aspiration or surgery should be further performed.

Objective To evaluate the diagnostic value of MR cholangiopancreatography(MRCP) using three-dimensional fast recovery fast spin-echo(3D FRFSE) in differentiating benign from malignant causes of biliary and pancreatic duct dilatation.Methods 106 cases suspected biliary and pancreatic duct dilatation underwent 3D FRFSE MRCP.The images were prospectively analysed by two skilled radiologists,and the results were compared with that of surgery,biopsy or follow-up.Results MRCP was successful performed at one time in all cases.On MRCP,the visual rate of intra-and extrahepatic bile duct was 100% and that of main pancreatic duct was 93.4%.80 patients had benign lesions: bile duct lithiasis(n=66),papillitis(n=6),descending part of duodenum diverticulitis(n=2),duodenal adenomatoid hyperplasia(n=1) and chronic pancreatitis(n=5).26 patients had malignant lesions: extrahepatic cholangiocarcinoma(n=9),ampullary carcinoma(n=5),gallbladder carcinoma(n=4) and pancreatic head carcinoma(n=8).The sensitivity,specificity and accuracy in differentiating benign from malignant causes of biliary dilatation were 92.3%,96.3% and 95.3%,respectively.Conclusion 3D FRFSE MRCP plays an important role in diagnosis of differentiating diagnosis of the causes of biliary dilatation in clinical practice.

Objective To establish a method for rapid preparation of antiserum against influenza virus (H7N9) hemagglutinin,and to study the possibility of using it in single radial immunodiffusion (SRID) assay for quantitative detection of antigen in H7N9 influenza vaccine.Methods Hemagglutinin proteins expressed in eukaryotic cells were used to immunize sheep.Serum samples were collected to detect antibody titers by ELISA and double immunodiffusion assay.Different concentrations of antiserum were used in SRID assay to get the optimized concentration.Results After 4 times of immunization,the antiserum titers achieved 1 ∶ 1 000 000 and 1 ∶ 32 as indicated by ELISA and double immunodiffusion assay,respectively.The antiserum could form a clear precipitation line in SRID assay.The detection of antigen in the range of 10 to 40 μg/ml showed good linearity in the standard curve.The antigen titers in six batches of H7N9 vaccine detected by this SRID assay were identical with those by SDS-PAGE assay.Conclusion The antiserum against H7N9 hemagglutinin for SRID assay was developed successfully,and could be used as a reagent for the quantitative detection of antigen in H7N9 influenza vaccine.

Objective To study the possibility of using heterogeneous antiserum in single radial immunodiffusion (SRID) for quantitative detection of HA in H7N9 influenza vaccine product when H7N9-specific antiserum is not available in order to establish a testing method for the detection of H 7N9 antigen in any urgent situation.Methods Antisera specific for H7N1, H7N2, H7N3 and H7N7 were obtained from NIBSC and used for SRID assay .Amino acid sequences of hemagglutinins were comparatively analyzed be-tween H7N9 virus and other viruses used to prepare heterogeneous antiserum .The titers of antisera against H7N9 and their homogenous antigens were detected by double immunodiffusion method .Based on the results of homology analysis and cross-reaction, a suitable antiserum was selected and its applicability was further validated by the SRID assay using H7N9 antigen.Results Influenza A virus subtype H7N3 that used for preparation of 07/278 antiserum showed the highest HA homology with H7N9 (97.14%).The titer of 07/278 antiserum against H7N9 antigen was 1 ∶8 as detected by double immunodiffusion assay .The H7N9 anti-gen and the 07/278 antiserum could form a clear precipitation line in SRID assay .The detection of H7N9 antigen in the range of 10 to 40μg/ml showed a good linearity in the standard curve .Conclusion The 07/278 antiserum from NIBSC can be used as an alternative reagent for the quantitative detection of hemaggluti -nin in H7N9 influenza virus vaccine .

Objective To compare signal characteristics and image qualities of MR diffusion-weighted imaging (DWI)at 1.5T and 3.0T in patients with the complex adnexal masses.Methods Magnetic resonance imaging including routine MRI and DWI(b=0 s/mm2 ,400 s/mm2 , 600 s/mm2 ,800 s/mm2 ,1 000 s/mm2 )of 1.5T (50 patients with 31 benign and 1 9 malignant lesions )and 3.0T (53 patients with 29 benign and 24 malignant lesions )were performed in 103 patients with histopathologically proved adnexal masses.The optimal b value was analyzed,and the apparent diffusion coefficient (ADC)value and signal intensity (SI)value and contrast to noise ratio (CNR)of solid and cystic components in adnexal masses from both 1.5T and 3.0T MR were respectively compared statistically.Results The 800 s/mm2 was the optimal b value in demonstrating adnexal masses at 1.5T and 3.0T.The CNR of solid and cystic components in adnexal masses were significantly higher at 3.0T than at 1.5T on all b values(all P =0.000).The difference in ADC value of solid lesions between 1.5T and 3.0T on all b values DWI had no statistically significant (all P >0.05),nor did the difference in SI value of solid lesions as well as ADC value of cystic lesions on b800 DWI(P >0.05).Conclusion MR diffusion-weighted imaging at 3.0T compared with 1.5T has quantitative and qualitative advantages of evaluating for adnexal masses,while the 800 s/mm2 is the optimal b value for both of them.

Objective To explore the safety and efficacy of laparoscopic cholecystectomy in different time points after endoscopic retrograde cholangiopancreatography in elderly patients with cholecystolithiasis and choledocholithiasis. Methods 99 elderly patients （≥60 years old）with cholecystolithiasis and choledocholithiasis treated by sequential LC after ERCP in the Department of Hepatobiliary and Pancreatic surgery in our hospital from January 2015 to June 2020 were analyzed. Aocording to different time points after ERCP, LC was divided into experimental group (within 1 day after ERCP) and control group (within 2-7 days after ERCP). The complications were followed up by telephone within 3 months after operation. Results After analysis，the difference between the experimental group and the control group in the total length of hospitalization [(13.0±4.6)d vs ( 15.1±4.4)d] and total hospitalization expenses (38 172.5±12 448.9) vs ( 42 535.4±8 814.6)] was statistically significant (P<0.05). However, there was no significant difference in the conversion rate of LC to laparotomy, the total postoperative complications , the length of hospital stay after LC，the amount of blood loss during LC and the time of LC operation between the two groups(P>0.05). Conclusion For elderly patients with cholecystolithiasis and choledocholithiasis, LC within 1 day after ERCP does not increase the difficulty of operation and postoperative complications，but shortens the hospitalization time, and it is economical and safe at the same time.

ObjectiveTo investigate the risk factors for open pancreatic necrosectomy (OPN), an effective treatment method for severe acute pancreatitis (SAP) after the failure of percutaneous catheter drainage (PCD), in patients with SAP. MethodsA retrospective analysis was performed for 156 patients with SAP who underwent surgical intervention based on the step-up approach in The Affiliated Hospital of Zunyi Medical University from January 1, 2010 to June 30, 2018, and according to whether OPN was performed, the patients were divided into PCD group with 126 patients and PCD+OPN group with 30 patients. Related clinical data were collected, including age, sex, etiology, blood calcium on admission, white blood cell count on admission, whether CTSI score was ＞7, APACHE-Ⅱ score, Ranson score, presence or absence of peripancreatic fluid accumulation, presence or absence of infection, presence or absence of multiple organ failure (MOF), and whether PCD was performed at more than 1 week after admission. The t-test was used for comparison of continuous data between groups, and the chi-square test was used for comparison of categorical data between groups; a multivariate logistic regression analysis was used to determine the independent predictive factors for OPN. ResultsThe probability of OPN was 19.2% for SAP patients in the later stage. Compared with the PCD+OPN group, the PCD group had a significantly lower proportion of patients with MOF on admission ［27.0% (34/126) vs 70.0% (21/30), χ2=19.642, P＜0.01］ and a significantly higher proportion of patients undergoing PCD at less than 1 week after admission ［61.9% (78/126) vs 20.0% (6/30), χ2=17.121, P＜0.01］. MOF on admission (odds ratio ［OR］=5.343, 95% confidence interval ［CI］: 1.832-15.583, P＜0.05), initial PCD performed at more than 1 week after admission (OR= 5.518, 95% CI: 1.742-17.477, P＜0.05), and infection on admission (OR=5.016, 95% CI: 1.322-19.378, P＜0.05) were independent risk factors for subsequent OPN in SAP patients. ConclusionSAP with MOF on admission, initial PCD performed at more than 1 week after admission, and SAP with infection on admission are independent risk factors for subsequent OPN in SAP patients undergoing PCD in the early stage based on the step-up approach. Timely identification of related risk factors helps to grasp the timing of OPN in clinical practice and improve the clinical prognosis of SAP patients.

Robot-assisted laparoscopy hepatectomy (RALH) is a new technique for surgical operation. Compared with conventional laparoscopic hepatectomy, RALH is more frequently used in complex liver tumor and liver tumor with special locations, but this technique is still under development and is limited by the burden of high costs and surgical devices. Meanwhile, there is a lack of generally accepted and confirmed clinical data, and therefore, the role of RALH is still under debate. This article reviews the surgical indication, learning curve, advantages, and limitations of RALH.