Application of CT perfusion imaging in diagnosis of pancreatic adenocarcinoma

Objective: To assess the value of CT perfusion imaging in diagnosis of pancreatic adenocarcinoma. Methods: Patients with pancreatic adenocarcinoma (n=39), acute pancreatitis (n=12) and normal pancreas (n=8) were included. Eight seconds after bolus injection of contrast agent (4.0 ml/s, 50 ml [I 300 mg/ml]), dynamic enhancement scanning was carried out for chosen sections by Siemens Bodyperfusion. Scanning parameters were 120-kV tube voltage, 35-mA tube current, 1-second acquisition time, 1-second circle time, and dosage 90.3 CTDIw. After dynamic enhancement scanning, intravenous injection of 50-60 ml contrast agent was given at 2.0 ml/s and routine scanning was performed 25 seconds and 45 seconds after injection. Images were transformed to MV300 workstation and processed with Siemens Perfusion CT/VA11A. Six pseudocolour perfusion images were obtained, and Flow, Flow without Vessels, Blood Volume, Peak Enhancement, Time to Start and Time to Peak were measured. Results: The values of Flow, Blood Volume, Peak Enhancement of pancreatic adenocarcinoma were lower than those of acute pancreatitis and normal pancreas (P0.01). Time to Start perfusion was not different in the 3 groups; Time to Peak of pancreatic adenocarcinoma group was longer than that of acute pancreatitis group (P0.05), but had no difference with that of normal pancreas. Pseudocolour perfusion images were convenient for qualitative diagnosis of disease, and perfusion values were needed for quantitative analysis. Pancreatic perfusion of normal pancreas was (0.84±0.32)ml/(min·ml) in this study. Conclusion: Compared with acute pancreatitis and normal pancreas, pancreatic adenocarcinoma has descended Flow, Blood Volume and Peak Enhancement. Pseudocolour perfusion images are beneficial for qualitative diagnosis.