Assessment of liver function by gadoxetic acid avidity in MRI in a model of rapid liver regeneration in rats.

This animal study investigates the hypothesis of an immature liver growth following ALPPS (associating liver partition and portal vein ligation for staged hepatectomy) by measuring liver volume and function using gadoxetic acid avidity in magnetic resonance imaging (MRI) in models of ALPPS, major liver resection (LR) and portal vein ligation (PVL). Wistar rats were randomly allocated to ALPPS, LR or PVL. In contrast-enhanced MRI scans with gadoxetic acid (Primovist®), liver volume and function of the right median lobe (=future liver remnant, FLR) and the deportalized lobes (DPL) were assessed until post-operative day (POD) 5. Liver function FLR/DPL was defined as the inverse value of time from injection of gadoxetic acid to the blood pool-corrected maximum signal intensity FLR/DPL multiplied by the volume FLR/DPL. In ALPPS (n = 6), LR (n = 6) and PVL (n = 6), volume FLR and function FLR increased proportionally, except on POD 1. Thereafter, function FLR exceeded volume FLR increase in LR and ALPPS, but not in PVL. Total liver function was significantly reduced after LR until POD 3, but never undercuts 60% of its pre-operative value following ALPPS and PVL. This study shows for the first time that functional increase is proportional to volume increase in ALPPS using gadoxetic acid avidity in MRI. [ABSTRACT FROM AUTHOR]