Fig 1.
Helical contrast-enhanced axial CT images of the intrahepatic PV of 3 different periportal halo grades.
(A) halo grade mild, (B) halo grade moderate, and (C) halo grade severe. Note the more horizontal oriented right branch and the right lateral lobe branches creating the appearance of “tram lines” (arrow). The segmental branches of the depicted left liver lobes are more vertically oriented and therefore creating “rings” or “collars” (arrow heads). Abbreviations: CT, Computed Tomography; PV, portal vein.
Fig 2.
Schematic drawing of the intrahepatic portal system.
Dorsal plane image showing the short right (RB) and long left branch (LB) which are further dividing into lobe and segmental branches. An example of the periportal halo is given along the left lateral lobe branch and is presented as thickened black line. Classification of the halo distribution into first (1st), second (2nd) and third (3rd) generation is marked with vertical lines. Abbreviations: PV, portal vein; GDV, gastroduodenal vein; CP, caudate process of caudate lobe; RLL, right lateral lobe; RML, right medial lobe; QL, quadrate lobe; LML, left medial lobe; LLL, left lateral lobe; PP, papillary process of caudate lobe; GB, gall bladder.
Table 1.
Summary of patient data sorted by hepatic, concurrent hepatic + extra-hepatic, extra-hepatic disease and no final diagnosis.
Fig 3.
Helical contrast-enhanced CT image of a dog with a cholangiocarcinoma.
Axial CT image showing multiple lobulated non-enhancing hypoattenuating masses in the caudate and left lateral lobe of the liver which were histopathologically confirmed as cholangiocarcinoma. Note how the tumor encases the intrahepatic portal branch and reduces the vessel’s diameter (arrows). The CVC is severely flattened and compressed by the mass effect of the tumor. There is a concomitant mild periportal halo seen in the periphery of the left lateral lobe (arrow head). Abbreviations: CT, Computed Tomography; PV, portal vein; CVC, caudal vena cava, Ao, Aorta; CL, caudate lobe; LLL, left lateral lobe.