Errors in the topographic diagnosis of liver diseases.

To identify the portal pedicles in liver pathology is difficult: anatomical variations are ignored and only the modal disposition is retained, the obliquity of the liver in situ is ignored: strongly inclined to the right, posteriorly and inferiorly (the anterior sector is above and to the right of the posterior sector, their pedicles in an antero-posterior radiogram are superposed); and the sizes of segments IV and VI are quite variable (embryologic result). This study was made with a collection of 111 vasculo-biliary acrylic casts. The main portal fissure containing the middle hepatic vein follows the axis of the cystic fossa, Actually the position of this axis varies from 180 to the right of the vein (gallbladder under segment V) and 14degrees to the left (gall-bladder under segment IV); the fissure reaches the inferior vena cava only at the limit of the upper surface of the liver, the vena cava is separated from the right and left livers by the dorsal sector. The anterior half of the right portal fissure is quite variable, it can reach the anterior liver from the main portal fissure up to the anterior portion of the right margin of the liver (segment VI variation); in 41% of the livers (n = 100), the right hepatic vein is in the right portal fissure; occlusion of the anterior or the posterior right arteries indicates the fissure. The left portal fissure is often confused with the left hepatic fissure (limit between academic left and right lobes). Segments breadths are measured in the upper surface of the liver. The largest segments are VIII, V, III and 11; their transversal breadth is also the largest (simple to double). In difficult cases, a tri-dimentional reconstruction of the pedicles should be made from an helicoidal tomodensitometry. (C) 2002 editions sclentifiques et medicales Elsevier SAS.