Clinical Study On Assessment Of Resectability Of Pancreatic Cancer With Multi-slice CT Angiography

Along with the appearance of the multislice spiral CT (MSCT),the accurate rate of imaging diagnosis,staging and preoperative assessment of resectability of pancreatic carcinoma increased.The examination and assessment of resectability on pancreatic carcinoma were investigated with MSCT.There were two parts in this research.Part one,to evaluate the enhancement degree of pancreatic parenchyma and the displaying effect of peri-pancreatic vessels through MSCT.Part two,to evaluate the various MSCT signs of peripancreatics vessels invasion by pancreatic carcinoma and the resectability of pancreatic carcinoma.Part IObjective To discuss the clinical application of multislice spiral CT (MSCT) triple-phase enhanced scanning of pancreas.Materials and Methods The scanner was GE Lightspeed 16-detector row computed tomography (CT).Contrast medium was injected by using 90～100ml nonionic contrast agent Omnipaque350mgI/ml,with the injection rate of 3ml/s. Triple-phase(i.e.arterial,pancreatic and portal phase) enhanced CT scanning were performed in 40 subjects without pancreatic disease. The results were statistically analyzed.Results Maximal enhancement value of pancreas during pancreatic phase was superior than the other phases(P<0.01). The displaying degree of peri-pancreatic arteries was of significant difference between arterial and pancreatic phase(P<0.01). The displaying degree of peri-pancreatic large veins was of no difference between pancreatic and portal phase(P<0.01).Conclusion MSCT is the optimal selection for the examination of pancreas, triple-phase enhanced scanning. It's playing an important role in evaluating pancreas,tumors and peri-pancreatic vessels.Part IIObjective To investigate various MSCT signs of vessels invasion of pancreatic carcinoma and then compare it with surgical results.Materials and Methods Eighty patients with pancreatic carcinoma thereafter confirmed by clinical signs or pathologic examinations(including 45 patients treated by surgery) underwent tri-phase MSCT combined with MSCTA. Reconstruction techniques include volume rendering technique(VR), multiplanar reconstruction(MPR), maximum intensity projection(MIP) and curve planar reconstruction(CPR). Peripancreatic vessels include celiac artery(CA), superior mesenteric artery(SMA), splenic artery(SA), portal vein(PV), splenic vein(SV), superior mesenteric vein(SMV). The invasion states were devided into 0～4 grades. To evaluate the imaging of 270 peripancreatic vessels, and then correlated it with surgical results.To calculate the sensitivity, specificity, positive prognostic value, negtive prognostic value and accurate rate of each grade.Results The invasion of peripancreatic vessels and its invasion degree are differe from the tumor's location and it's size. The sensitivity decreased by the increasing of the grade, but the specificity increased by the increasing of the grade. Using grade two as the resection standard of pancreatic cancer, the sensitivity and specificity were higher.Conclusion MSCTA improves the ability to predict the resectability of pancreatic carcinomas.