Intraoperative assessment of liver function by near-infrared fluorescent camera in liver surgery – iFLOW

The liver has a remarkable capability to regenerate. A healthy human liver can regenerate more than 2/3 of its mass. However, patients undergoing liver surgery often suffer from liver diseases accompanied by a significant reduction in liver function and regenerative capacity. Post-operative liver failure is the main cause of short-term mortality (around 5% at 3 months after surgery) after hepatectomy (5000 / year in France) due to insufficient functional liver mass. Today, limits of liver surgery and partial liver transplantation are based on empiric minimal acceptable liver volume that is preoperatively defined on volumetric reconstruction using CT-scan. These limits are defined according to a priori ratios between liver volume and liver function that depend on the quality of liver parenchyma and the therapeutic situation. However, the evaluation based on these threshold values fails if either the a priori ratios do not apply for a patient or if the partial liver transplantation or major hepatectomy lead to a drastic modification of the hepatic hemodynamics. The aim of this project is double. Firstly, relationships between liver function, blood flows and architecture along with liver volume after major hepatectomy will be carefully analyzed by combining experiments and modeling on multiple levels and scales. These results will be used to develop an alternative evaluation procedure based on innovative tools, particularly near-infrared fluorescence imaging (that permits intraoperative evaluations of liver function), in order to improve identification of possible or likely post-operative liver failure as early as possible. In this way a critical liver function decrease can be duly treated. Preliminary studies in pigs indicate that patients in which liver failure is likely to occur, may significantly benefit from an implantable surgical device capable of modulating the diameter of the portal vein hence controlling the portal venous pressure into the liver. The second goal of this project is to explore the conditions for the optimal use of this device for such patients.
For both goals, mathematical models at organ, lobular and cellular levels will be built within an iterative process of model refinement and experimental and clinical data acquisition. The emerging multiscale model framework linking models at various spatial scales will thus provide a predictive tool to better understand how the measured data in different parts of the blood circulation, bile and tissue, reflect liver functional changes depending on the surgical procedure including transplantation as well as the following liver regeneration process.


This highly multidisciplinary project involves clinicians and researchers specialized in liver surgery and liver transplantation (DHU Hepatinov - Hôpital Paul Brousse - Villejuif), mathematicians specialized in the modeling and computer simulations of biological flows, tissue growth and remodeling, and their biomedical applications (INRIA), a SME involved in intra operative fluorescence imaging (Fluoptics™) that will industrialize the imaging system and market it after the project, and a SME that had developed an adjustable vascular ring (MID-AVR™) allowing to modulate postoperatively the liver blood perfusion.