Figure 17b. Geographic alteration in lobar echotexture secondary to a Klatskin tumor. (a) Intercostal oblique US scan through the liver shows marked lobar atrophy of the right lobe (rt). In addition, there is geographic alteration in lobar echotexture, with the right lobe substantially less echogenic than the left lobe (lt). (b) Axial US scan through the left lobe and porta hepatis shows segmentally dilated ducts with nonunion, echotexture variation, and a subtle Klatskin tumor (arrowheads). Segments 2, 3, and 4 are clearly marked.