Fig. 1: The sinusoidal network in the hepatic lobule shows stable structural parameters.

a Schematic of liver lobes composed of the left lobe (LL), left median lobe (LML), right median lobe (RML), right lobe (RL), and caudate lobe (CL). b The sinusoidal area of the hepatic lobule has a hepatic cord structure in which hepatocytes are arranged linearly along sinusoidal endothelial cells. c 3D image of the sinusoidal area. Blood flows to the central vein from the portal vein, and we tracked the sinusoid from the portal area to the central vein. d Spotting of each branching point (left) and identification of each spot (right) associating three-dimensional coordinates. e Measurement of branching angles and sinusoidal diameter. We labelled the new spots as B and C (left) and calculated the angle A with three-dimensional coordinates (right). f Schematic of two branch patterns. The red spot has a single inflow port and double outflow ports, and the yellow spot has a double inflow port and single outflow ports (left). We analysed the branches in order from the branching root (right). g Distribution of angles of branched vessels (n = 105 branching points). h Relation of vessel diameter and branching hierarchy (n = 8, 14, 13, 16, 13, 9 vessels at 1st, 2nd, 3rd, 4th, 5th, 6th branching, respectively). i Schematic of branching rotation angle measurement. The branched vessels were projected to the orthogonal plane (YZ plane) perpendicular to the reference XY plane. j Distribution of rotation angles of branched vessels (n = 199 branching points). k Layered structure of the sinusoidal network (left). Blue, green, yellow, and pink show the vessel groups with the same root. The red vessels are the transfer vessels that connected each layer (right). l Quantitative analysis of vascular volume and surface area in transfer vessels and layered vessels (n = 4 and 3 area for layered and transfer vessels, respectively).