The Role of ICG in Robot-Assisted Liver Resections

Abstract

Introduction: Robotic-assisted liver surgery (RALS) with its known limitations is gaining more importance. The fluorescent dye, indocyanine green (ICG), is a way to overcome some of these limitations. It accumulates in or around hepatic masses. The integrated near-infrared cameras help to visualize this accumulation. We aimed to compare the influence of ICG staining on the surgical and oncological outcomes in patients undergoing RALS. Material and Methods: Patients who underwent RALS between 2014 and 2021 at the Department of General Surgery at the University Hospital Schleswig-Holstein, Campus Kiel, were included. In 2019, ICG-supported RALS was introduced. Results: Fifty-four patients were included, with twenty-eight patients (50.9%) receiving preoperative ICG. Hepatocellular carcinoma (32.1%) was the main entity resected, followed by the metastasis of colorectal cancers (17%) and focal nodular hyperplasia (15.1%). ICG staining worked for different tumor entities, but diffuse staining was noted in patients with liver cirrhosis. However, ICG-supported RALS lasted shorter (142.7 ± 61.8 min vs. 246.4 ± 98.6 min, p < 0.001), tumors resected in the ICG cohort were significantly smaller (27.1 ± 25.0 mm vs. 47.6 ± 35.2 mm, p = 0.021) and more R0 resections were achieved by ICG-supported RALS (96.3% vs. 80.8%, p = 0.075). Conclusions: ICG-supported RALS achieve surgically and oncologically safe results, while overcoming the limitations of RALS.

Keywords: ICG; hepatic surgery; indocyanine green; liver surgery; minimally invasive hepatic surgery; robot-assisted hepatic surgery; robotic hepatic surgery; robotic liver surgery; robotic surgery.

Figure 1

Intra-operative robotic image in white light (C) and intraoperative near-infrared (D) image of CRLM (rim phenomenon) with corresponding preoperative T-weight MRI-scans (A,B)

Figure 2

Intra-operative near-infrared image (A,C) and normal white light image (B,D) with the corresponding image of the IOUS of unequivocal staining (A,C) of a HCC, corresponding with the IOUS (HCC) and diffuse staining and not corresponding with the ICG-based image (C,D) of a CCC.

Figure 3

Intra-operative fluorescence imaging and histopathological image of the corresponding area confirming R0 resection. Histological images of tumor free liver tissue in the marginal area with portal fields and a sparse round cell infiltrate (A) HE staining, magnification 200×. Histological images of HCC with trabecular and pseudoglandular growth from the same patient (B) HE staining, magnification 200×. Intraoperative imaging of the fluorescent tumor after ICG application (C), preoperative MRI scan, showing the lesion (D).