Is embolization of segment 4 portal veins before extended right hepatectomy justified?

Background. Preoperative portal vein embolization (PVE) is increasingly used as a preparation for major hepatectomy in patients with inadequate liver remnant volume or function. However, whether segment 4 (S4) portal veins should be embolized is controversial. The effect of S4 PVE on the volume gain of segments 2 and 3 (S2+3) was examined. Methods. Among 73 patients with uninjured liver who underwent right portal vein embolization (RPVE, n=15) or RPVE extended to S4 portal veins (RPVE+4, n=58), volume changes in S2+3 and S4 after embolization were compared. Clinical outcomes and PVE complications were assessed. Results. After a median of 27 days, the S2+3 volume increased significantly after both RPVE and RPVE+4, but the absolute increase was significantly, higher for RPVE+4 (median, 106 mL vs 141 mL; P=.044), as was the hypertrophy rate (median, 26% vs 54%; P=.021). There was no significant difference between RPVE,: and RPVE+4 in the absolute S4 volume increase (52 mL for RPVE vs 55 ml for RPVE+4; P=.61) or the hypertrophy rate of S4 (30% for RPVE vs 26% for RPVE+4; P=.45). Complications of PVE occurred in 1 patient (7%) after RPVE and 6 (10%) after RPVE+4 (P>.99). No PVE complication precluded subsequent resection. Curative hepatectomy was performed in 13 patients (87%) after RPVE and 40 (69%) after RPVE+4 (P =.21). Conclusions. RPVE+4 significantly improves S2+3 hypertrophy compared with RPVE alone. Extending RPVE to S4 does not increase PVE-associated complications. (Surgery 2008,-144:744-51.)