Objective To describe the diagnosis and preoperation evaluation of pancreatic carcinoma with spiral CT three-phase contrastenhanced scan and post-processing.Methods Three-phase helical CT enhanced scan and post-processing images of 41 patients with pancreatic carcinoma were retrospectively analyzed,including the location,size,characteristic of tumor and peripancreatic blood vessels,the results were compared with that of surgery.Results Low degree of enhancement of pancreatic carcinoma in pancreatic phase was showed compared with parenchymal phase.There was significant difference in density between focus and normal pancreas,the lesions were showed clearly.In comparison with surgical results,the diagnostic accuracy of CT was 80.7% and the accurate rate in evaluating the metastasis was 75.8%.Conclusion Three-phase helical CT enhanced scan and postprocessing are of great value in diagnosis of pancreatic carcinoma and it is helpful in choosing the treatment program preoperatively and assessing the respectability of tumors.

Objective To evaluate the CT and MR imaging findings of salivary duct carcinoma (SDC) in order to enhance the understanding of this rare disease.Methods A retrospective analysis of CT and MRI images was performed in 20 patients (14 males and 6 females,median age 56 years old) with pathologically proved SDC.CT and MR images were evaluated with respect to the following feature factors:location,size,morphology,margin,CT density/ MR signal intensity and enhancement pattern.Results Thirteen lesions were located in parotid gland,4 lesions in submandibular gland,1 lesion in sublingual gland and 2 lesions in the buccal spaces.The maximum diameter of SDC ranged from 1.5 to 7.0 cm,mean (3.5 ±0.9) cm.Five cases demonstrated round or oval round masses with well-defined margin,15 cases demonstrated irregular masses with ill-defined edge.Among them,the peritumoral fat tissues were infiltrated in 7 cases,the preauricular skin were invaded in 3 cases,the jaw muscles were invaded in 2 cases and the parapharyngeal space,pterygoid muscle,retromandibular vein was invaded in 1 case respectively.Lesions were homogeneous in 4 cases and heterogeneous in 16 cases.Seven lesions showed varied calcifications.Lesions were homogeneous iso-intense in 1 case and heterogeneous iso-intense in 2 cases on T1WI,heterogeneous hyperintense in all cases on T2WI.On post contrast images,lesions demonstrated remarkable enhancement in 17 cases,moderate enhancement in 3 cases.Enlarged cervical lymph nodes were found in 12 cases.Conclusions SDC has nonspecific imaging characteristics.CT and MR examinations can accurately demonstrate the extent of tumor involvement and are helpful to provide more comprehensive information for SDC management.

Objective To explore the CT and MR imaging findings of acinic cell carcinoma (ACC)in salivary gland and enhance the diagnosis of this rare disease.Methods The CT and MR imaging characteristics of 20 patients (7 males and 13 females,median age 44 years old) with pathologically proved ACC were retrospectively reviewed.CT and MR images were evaluated in relation to the following: location,size,morphology,margin,CT density/MR signal intensity and enhancement pattern.Results Twelve lesions were located in parotid gland,two lesions in maxillary Sinus,and one lesion in submandibular,parapharyngeal,infratemporal fossa,buccal,nasal cavity,and hard palate respectively.The size of lesions were 0.7～5.8 cm.Sixteen lesions less than 3 cm in size demonstrated round or oval round masses with well defined margin.Four lesions more than 3 cm in size demonstrated irregular masses with unclear margin.Among them,bony destruction of the wall of the maxillary sinus was noted in 3 cases,and the preauricular skin was invaded in 1 case.The densities (signal intensity) were homogeneous in 6 cases and heterogeneous in 14 cases.Lesions were slightly low density in 11 case and isodensity in 3 cases on CT plain scan.Lesions were homogeneous isointense in 2 cases and heterogeneous isointense in 4 cases on T1WI,heterogeneous hyperintense in all cases on T2WI.On post contrast images,lesions demonstrated remarkable enhancement in 14 cases,moderate enhancement in 2 cases and mild enhancement in 3 cases.Conclusions The imaging characteristic of ACC were nonspecific.CT and MR could accurately detect the extent of tumor involvement and was helpful to provide more comprehensive information for the strategy of clinic therapy.

Objective To investigate the differential diagnostic features of subtpes of renal cell carcinoma (RCC) using CT scan.Methods The CT appearances of 53 RCCs,including 28 clear cell RCCs (CCRCC),6 Xp11.2 /TFE RCCs (Xp11.2 /TFE RCC),7 collecting ducts RCCs (CDC),12 chromophobe RCCs (CRCC),were retrospectively analyzed and compared with finding of pathology.Dynamic contrast-enhanced CT (DCE-CT) was conducted in each case after intravenous administration of contrast agent,and the data was analyzed by AVONA and LSD text.Results On unenhanced and enhanced CT,most CCRCCs and CDCs showed heterogeneous density (23/28,6/7),with necrosis (21/28,6/7),and most Xp11.2/TFE RCCs,CRCCs showed homogeneous density(5/6,8/12).Most CCRCCs,Xp11.2/TFE RCCs and CRCCs had clearly boundaries with well demonstrated at enhanced CT delayed phase (25/28,6/6,10/12),CDCs had unclearly boundaries (6/7),and most CCRCCs had lymph node or other metastasis (19/28).A phenomenon of quick staining and quick fainting was observed in CCRCCs.Xp11.2/TFE RCCs,CDCs,CRCCs showed delayed enhancement.On unenhanced CT,the Xp11.2/TFE RCC attenuation was greater than CCRCC,CDC,CRCC and normal renal cortex (53.7±4.1 vs 45.8±3.6 vs 41.4±2.4 vs 47.7±3.6 vs 41.5±5.1,F=5.458,P＜0.01,respectively).The enhancement degree was highest for CCRCCs,lowest for CDCs,and intermediate for Xp1 1.2/TFE RCCs and CRCCs.The enhancement degree of Xp1 1.2/TFE RCC was higher than that of the CDC and CRCC (P＜ 0.01).The enhancement degree of Xp11.2/TFE RCC and CRCC were higher than that of the normal renal medulla at cortical and medullary phases (P＜0.01),but lower than that of the renal medulla on delayed phase (P＜0.01).The enhancement degree of CDC were lower than that of the normal renal cortex and medulla on cortical,medullary and delayed phases (P＜0.05).Conclusions CT could distinctly show imaging features of CCRCC,Xp1 1.2/TFE RCC,CDC and CRCC,which were related to their pathological characteristics,and these features were helpful in predicting a specific subtype of RCC.

Objective: To investigate the vascular anatomy of the stomach, especially the right gastroepiploic artery for the reconstruc-tion of a gastric tube during esophagectomy. Methods: The vascular anatomy of the stomach was studiing in 28 embalmed human specimens provided by the Department of Anatomy, Shanghai Medical College, Fudan University, included 10 female and 18 male spec-imens. The length and diameter of gastric vessels were measured. The ratio of the length of the right gastroepiploic artery to the length of the greater curvature was calculated. Anastomosis between the left and right gastroepiploic arteries was also assessed. Re-sults: Twenty-five left gastric arteries were observed in the autopsies, with the mean diameter of 3.40 (2.10-6.40) mm. Twenty-one right gastric arteries were measured, with the mean diameter of 1.97 (0.68-3.56) mm. Twenty-six left gastroepiploic arteries were ob-served, with the mean diameter of 1.87 (0.80-2.96) mm. Twenty-eight right gastroepiploic arteries were measured, with the mean di-ameter of 2.82 (1.58-4.80) mm. The mean lengths of the 28 right gastroepiploic arteries and their greater curvatures were 216.71 (120-318) mm and 356.39 (248-487) mm, respectively. The ratio of the length of right gastroepiploic arteries and greater curvatures was 0.61 (0.45-0.82). The anastomosis between the left and right gastroepiploic arteries was observed in 60.7% (17/28) of the specimens. Conclusions: The length and diameter of gastric vessels were calculated. It was assumed that the right gastroepiploic artery provides an average of 61% of the blood supply for the great curvature. In addition, the anastomotic branch of the right and left gastroepiploic arteries was observed in 60.7% specimens. These anatomical data allow surgeons to estimate the blood supply and to choose an opti-mal method of gastric tube reconstruction during esophagectomy.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.