Extreme liver resections with preservation of segment 4 only

Figure 1 Schematic representation of two-stage hepatectomy with preservation of segment 4 only using outflow modulation. A: During the first stage, a right hepatectomy with middle hepatic vein is performed along with an associated induction of congestion in the left lobe; B: Redistribution of portal flow (increased inflow to segment 4 after territorial congestion of segments 2/3) optimizes hypertrophy of segment 4 and avoids hypertrophy of segment 2 and 3; C: The second stage of procedure, a left lobectomy, is performed.

Figure 2 Computed tomography-based volumetry. A: Before the first stage of liver resection; B: Before the second stage of the procedure. Modulated congestion of the left lobe associated with right hepatectomy led to a significant hypertrophy rate of segments 4 and 1 (156%) but only a modest hypertrophy rate of segments 2 and 3 (24%). Modified from Balzan et al[15].