Evaluating changes in hepatic microcirculation in mild and severe acute pancreatitis through dynamic volume perfusion computed tomography

Abstract Objectives: Based on one-stop upper abdominal dynamic volume perfusion computed tomography (dVPCT) data stacks, we reconstructed images from multiple contrast enhancement phases to determine the severity of acute pancreatitis (AP) and further evaluated hepatic perfusion in mild and severe AP through multiple perfusion parameters. Methods: We prospectively enrolled 77 patients from the database of upper abdominal dVPCT between July 2018 and April 2019, including 62 with AP, as well as 15 without pancreatic and hepatic disorders as the control group. All patients underwent dVPCT, and we reconstructed the mean temporal arterial, mean temporal pancreatic, and mean temporal portal venous images to evaluate the severity of AP according to the CT severity index. We further divided AP into mild and severe AP groups. A deconvolution algorithm was applied to calculate multiple hepatic perfusion parameters, including blood flow (BF), blood volume (BV), arterial liver perfusion (ALP), portal venous liver perfusion (PVP), mean transit time (MTT), hepatic perfusion index (HPI), and time to peak (TTP). Results The hepatic perfusion parameters BF, BV, PVP, MTT, HPI, and TTP differed significantly between the severe AP patients and control group. Only PVP and MTT were significantly different between the mild AP patients and the control group. The mild AP group had significantly higher BF, BV and MTT values but a significantly lower TTP than the severe AP group. Conclusions Hepatic perfusion differed according to the severity of AP. Severe AP shows altered hepatic haemodynamics and disturbances of the hepatic microcirculation.