An evaluation of the effectiveness of 3D virtual imaging combined with intraoperative ultrasonography to guide liver staining in anatomic segmental hepatectomy

Identification of a tumor-bearing portal territory using indocyanine green (ICG) fluorescence imaging (IGFI) facilitates precise laparoscopic anatomic hepatectomy (LAH). However, it is technically challenging to perform a transhepatic portal injection of ICG or to clamp the target portal pedicle and inject ICG during LAH. Herein, we aimed to investigate the feasibility and efficacy of portal territory identification using IGFI under the combined guidance of three-dimensional (3D) virtual imaging and intraoperative ultrasound (IOUS) in LAH. We enrolled patients eligible for LAH in the current study between June 2020 and April 2023. All patients had preoperative surgical planning based on 3D virtual imaging in which the boundaries of the tumor-bearing portal territory were displayed and the predicted remnant liver volumes (PRLVs) were calculated. We then conducted ICG fluorescence liver-segment staining and LAH under the combined guidance of 3D virtual imaging and IOUS. Actual remnant liver volumes (ARLVs) were calculated using 3D virtual imaging after surgery. Of the 73 patients who achieved a valid demarcation by IGFI, 14 (19.2%) underwent hemi-hepatectomy, while 19 (26%) and 40 (54.8%) underwent sectionectomy and segmentectomy, respectively. The IGFI-identified intraoperative hepatic segment boundaries were highly matched with the boundaries of the tumor-bearing portal territory in the 3D virtual images in 72 (98.6%) patients, and we observed that the ARLVs and PRLVs were also robustly correlated (<i>r</i> ² = 0.8734, <i>p</i> < 0.0001). In summary, 3D virtual imaging and IOUS contribute significantly to the staining and identification of a tumor-bearing portal territory and the accurate implementation of LAH.