HEPATIC PSEUDOLESION IN THE LEFT LOBE AROUND THE FALCIFORM LIGAMENT AT HELICAL CT

PURPOSE: To determine the prevalence and possible cause of pseudolesio ns in the left hepatic lobe around the falciform ligament at hepatic h elical computed tomography (CT). MATERIALS AND METHODS: Portal venous- dominant CT scans of 472 consecutive patients were reviewed. CT of the left hepatic lobe was performed after injection of contrast material into the portal vein in 73 patients, the hepatic artery in 32, and the internal thoracic artery in four. The scans were compared with those obtained at helical CT, and the findings were analyzed. RESULTS: Pseud olesions were seen on 64 (14%) of 472 helical CT scans and correlated well (accuracy, 96%) with portal perfusion defects. They were not more enhanced than the surrounding liver parenchyma at CT arteriography wi th hepatic artery injection but were enhanced in two patients at CT ar teriography with internal thoracic artery injection. CONCLUSION: Pseud olesions are caused by portal perfusion defects and may receive an abe rrant blood supply.