Multimodal perioperative assessment of liver function and volume in patients undergoing hepatectomy for colorectal liver metastasis: a comparison of the indocyanine green retention test, (99m)Tc mebrofenin hepatobiliary scintigraphy and gadoxetic acid enhanced MRI

OBJECTIVES: To compare the dynamic changes in future liver remnant (FLR) function and volume after hepatectomy and to evaluate the associations between three modalities in assessment of liver function. METHODS: Liver function and volume were quantified pre-operatively, at post-operative day (POD) 7 and POD 28 in 10 patients with colorectal liver metastases undergoing hemihepatectomy using the indocyanine green retention (ICG) test, hepatobiliary scintigraphy (HBS) and gadoxetic acid-enhanced MRI. The (99m)Tc mebrofenin uptake rate in the FLR was applied as a reference of liver function. MRI-derived parameters including liver-to-muscle ratio (LMR), liver-to-spleen ratio (LSR) and hepatocellular uptake index (HUI) were used for liver function assessment. Spearman’s correlation analysis was used to evaluate the associations. RESULTS: Increase in liver function ranged from 13 to 152% (median 92%) and in volume from 37 to 134% (median 79%). There was no significant discrepancy in increase between FLR function and volume during the first month following hepatectomy. LMR showed a significant correlation to ICG test (r = −0.66, p < 0.05) while LSR had an association with standardized FLR function obtained by HBS (r = −0.71, p < 0.05). During the first week after hepatectomy, pre-operative HUI and LMR showed the strongest correlation to the FLR growth in function and volume respectively (p < 0.05). CONCLUSION: The observed growth in FLR volume is closely related to the functional increase within 1 month after hepatectomy. Gadoxetic acid-enhanced MRI might substitute HBS for regional liver function assessment and provide an imaging tool for liver growth prediction. ADVANCES IN KNOWLEDGE: Liver function growth was parallel with liver volume increase during the perioperative period. Liver function assessment with gadoxetic acid-enhanced MRI was comparable with that of HBS indicating that gadoxetic acid-enhanced MRI could substitute HBS for regional liver function evaluation.