Hepatic parenchymal perfusion abnormalities after pancreaticobiliary surgery - Evaluation with dynamic helical CT

Purpose. To evaluate perfusion abnormalities of the liver after pancreaticobiliary surgery. Material and Methods: We retrospectively evaluated 128 patients with pancreaticobiliary malignant tumors who had been examined both before and after surgery by means of helical CT of the liver. An infusion of 3 ml/s of 60% nonionic contrast material was followed by helical CT of the liver in a sequential arterial phase, portal venous phase, and equilibrium phase. Results: Of 128 patients, we followed 97. In 21 patients (22%) we found 47 lesions with perfusion abnormalities that were detected 1-33 months (mean 6.6 months) after the operation. All patients were asymptomatic. The shape of each perfusion abnormality was characterized as geographic (n=23, 47%)-wedge-shaped (n=21, 45%), or round (n=3, 8%). The abnormalities were seen in the arterial phase in 46 lesions (98%), in the portal venous phase in Is lesions (38%), and in the equilibrium phase in 1 lesion (0.2%). In all lesions, the size either decreased spontaneously, or it remained unchanged for more than one year. Conclusion. Perfusion abnormalities of the liver may occur in patients who undergo pancreaticobiliary surgery. This findings should not be confused with hypervascular metastases.