Systematic review of the use of pre-operative simulation and navigation for hepatectomy: current status and future perspectives.

Pre-operative simulation using three-dimensional (3D) reconstructions have been suggested to enhance surgical planning of hepatectomy. Evidence on its benefits for hepatectomy patients remains limited. This systematic review examined the use and impact of pre-operative simulation and intraoperative navigation on hepatectomy outcomes. A systematical searched electronic databases for studies reporting on the use and results of simulation and navigation for hepatectomy was performed. The primary outcome was change in operative plan based on simulation. Secondary outcomes included operating time (min), estimated blood loss, surgical margins, 30-day postoperative morbidity and mortality, and study-specific outcomes. From 222 citations, we included 11 studies including 497 patients. All were observational cohort studies. No study compared hepatectomy with and without simulation. All studies performed 3D reconstruction and segmentation, most commonly with volumetrics measurements. In six studies reporting intraoperative navigation, five relied on ultrasound, and one on a resection map. Of two studies reporting on it, the resection line was changed intraoperatively in one third of patients, based on simulation. Virtually predicted liver volumes (Pearson correlation r = 0.917 to 0.995) and surgical margins (r = 0.84 to 0.967) correlated highly with actual ones in eight studies. Heterogeneity of the included studies precluded meta-analysis. Pre-operative simulation seems accurate in measuring volumetrics and surgical margins. Current studies lack intraoperative transposition of simulation for direct navigation. Simulation appears useful planning of hepatectomies, but further work is warranted focusing on the development of improved tools and appraisal of their clinical impact compared to traditional resection.