Changes in arterial and portal perfusion in embolized and nonembolized hepatic lobes after portal vein embolization evaluated by helical computed tomography

We evaluated the changes in hepatic arterial and portal perfusion in nonemb olized as well as in embolized lobes after portal venous branch embolizatio n (PVE) with dynamic helical computed tomography (CT). Six patients with he patic malignancies, who underwent PVE prior to a subsequent hepatectomy, we re the subjects of this study. We performed CT examinations before PVE and 2 weeks after PVE to make a volumetric analysis. At the same time, we perfo rmed single-location dynamic sequences after the injection of a 50-ml bolus of contrast medium, and we then created time-density curves from circular regions of interest drawn over the aorta, parenchyma of the right and left lobe of the liver, and spleen. We calculated the arterial perfusion index ( ml/min per ml of tissue) and the portal perfusion index by dividing the max imum rate of enhancement of the liver before and after the splenic peak by the peak aortic enhancement. We then calculated the arterial and portal flo ws (ml/min) from the perfusion index and values of CT volumetry. In the rig ht lobe, where the portal flow was occluded, the arterial perfusion index a nd flow increased significantly after PVE. In contrast, the arterial perfus ion index and flow both decreased in the left lobe after PVE in a reverse r esponse to the increase in the portal perfusion index and flow. The total a rterial flow of the liver thus seemed to slightly increase; however, the ch ange was not significant. By performing PVE an increased arterial perfusion was induced in the embolized lobe, with a concomitant decrease in arterial perfusion in the nonembolized lobe.