Liver Volumetry and Liver-Regenerative Interventions: History, Rationale, and Emerging Tools

Background Postoperative hepatic insufficiency (PHI) is the most feared complication after hepatectomy. Volume of the future liver remnant (FLR) is one objectively measurable indicator to identify patients at risk of PHI. In this review, we summarize the development and rationale for the use of liver volumetry and liver-regenerative interventions and highlight emerging tools that could yield new advancements in liver volumetry. Methods A review of MEDLINE/PubMed, EMBASE and Cochrane Library databases was conducted to identify literature related to liver volumetry. The references of relevant articles were reviewed to identify additional publications. Results Liver volumetry based on radiological imaging was developed in the 1980s to identify patients at risk of PHI and later used in 1990’s to evaluate grafts for living donor living transplantation. The field evolved in the 2000s by the introduction of standardized FLR (sFLR) based on the hepatic metabolic demands, and in the 2010s by the introduction of the degree of hypertrophy (DH) and kinetic growth rate (KGR) as measures of the FLR regenerative and functional capacity. Several liver-regenerative interventions, most notable portal vein embolization, are used to increase resectability and reduce the risk of PHI. In parallel with the increase in automation and machine assistance to physicians, many semi- and fully automated tools are being developed to facilitate liver volumetry. Conclusion Liver volumetry is the most reliable tool to detect patients at risk of PHI. Advances in imaging analysis technologies, newly developed functional measures, and liver-regenerative interventions have been improving our ability to perform safe hepatectomy.