Minimally invasive liver surgery offers several advantages. However, despite these advantages, laparoscopic liver surgery remains challenging because of its intrinsic limitations. Robotic liver surgery is emerging as a minimally invasive surgery to overcome the disadvantages of laparoscopy. The robotic surgical system offers a stable camera platform, eliminates physiological tremors, augments surgical dexterity, and improves ergonomics [1,2].

Although the advantages of robotic platforms are significant, the lack of a robotic Cavitron ultrasonic surgical aspirator (CUSA; Dentsply Sirona) is still a cause for concern among surgeons accustomed to utilizing it for parenchymal transection. Nonetheless, with adequate experience and the aid of reliable and enhanced three-dimensional visualization, many robotic surgeons have successfully used robotic Harmonic ACE curved shears (Intuitive Surgical Inc.) [3,4].

Here, we share a method using robotic Harmonic ACE curved shears for parenchymal transection using a video clip.

From June 2019 to December 2022, 53 robotic hepatectomies for liver diseases and live donors were performed at Dong-A University Hospital. A total of 39 out of 53 were classified as major. During robotic hepatectomy, robotic Harmonic ACE curved shears were used for parenchymal transection in all cases.

Patient information within the video clip

A 66-year-old female patient was diagnosed with right colon cancer and liver metastasis. Before colon surgery, she had undergone laparoscopic distal gastrectomy for a 5-cm gastric gastrointestinal stromal tumor at 5 years of age. There was no significant past medical history besides the operation. She had undergone a laparoscopic right hemicolectomy. The final pathological stage was determined to be T2N2M0. Unfortunately, 9 months later, metastatic liver masses were noted on computed tomography and magnetic resonance imaging (Fig. 1) during the regular follow-up period. A multidisciplinary team decided to perform surgical excision with a robotic right hepatectomy.

Figure 1. Preoperative computed tomography (A) and magnetic resonance imaging (B, C) show liver metastasis in S5 and S6.

Surgical procedure

This study focused only on parenchymal transection during robotic right hepatectomy (Supplementary Video 1). Therefore, we encourage references to our previously published paper on the detailed surgical procedure for robotic hepatectomy [5].

Fortunately, there were no open conversions or major complications in the 53 patients. Three minor bile leakages occurred during this study.

In our case, the total operative and parenchymal transection times were 163 and 32 minutes, respectively. During parenchymal transection, the Pringle maneuver (15-minute duration) was used twice to maintain a dry field. No intraoperative transfusions were performed. The patient had an uneventful postoperative course and was discharged on the 7th postoperative day in good condition. The final pathological diagnosis was metastatic adenocarcinoma with free surgical margins.

Parenchymal transection is a fundamental aspect of minimally invasive liver resection. Inadequate sealing of the vascular and biliary structures can result in bile leakage or bleeding, potentially causing postoperative complications and mortality. Several techniques and devices have been developed for parenchymal transection during minimally invasive liver resection, such as the clamp-crushing technique (Integra Life Sciences), ultrasonic devices, staplers, and mono- and bipolar devices.

However, the most suitable device for robotic parenchymal transection has not yet been determined. The two biggest barriers to the uptake of robotic hepatectomy are the high cost and instrument limitations, and transection of the liver parenchyma is the main issue in robotic hepatectomy [6]. Moreover, the CUSA, which is mainly used in open and laparoscopic hepatectomies, cannot be used effectively in robot consoles.

Currently, the robotic Harmonic ACE curved shears with robotic bipolar cautery (Maryland bipolar forceps; Intuitive Surgical Inc.) are the most frequently used devices for parenchymal transection during robotic liver resection [7].

Nevertheless, the transection axis must be very well planned to use Harmonic ACE curved shears because it has no endo-wrist function, and the opening and closing action of the harmonic jaw would be similar to that used in the clamping-crushing technique. Additionally, the activation of the harmonic scalpel with the opening of the jaw is similar to the vibration of the CUSA (Fig. 2). The utilization of this technique for separating tubular structures in the liver parenchyma is highly effective and safe. Consequently, this is one of the most crucial techniques demonstrated in this video clip.

Figure 2. The open and close action of the harmonic scalpel jaw (A) is akin to the Kelly clamp crush technique, and when activated (B) with an open jaw, it closely resembles the vibration of Cavitron ultrasonic surgical aspirator (Dentsply Sirona).

Recently, the EndoWrist One Vessel Sealer (on the Xi/X robotic systems, EndoWrist One Vessel Sealer Extend; Intuitive Surgical Inc.) is a fully wristed robotic energy device (60° of articulation in all directions for the Extend) used for parenchymal transection [8]. While vessel sealers help overcome the absence of articulation in Harmonic ACE curved shears, the presence of a blunt tip and the larger body of the vessel sealer are considered potential obstacles in performing precise parenchymal dissections.

It is anticipated that harnessing the advantages and disadvantages of Harmonic ACE curved shears and vessel sealers will be highly beneficial for robotic liver resection in the near future.

Several recent studies have reported that robotic liver resection is safe and feasible. In particular, if the principle of Harmonic ACE curved shears is utilized effectively, Harmonic ACE curved shears can become safe and reproducible energy devices for parenchymal transection during robotic liver resection.

Ethical statements

This study was approved by the Ethics Committee of the Dong-A University Hospital (No. DAUHIRB-23-091). The requirement for informed consent was waived due to the retrospective nature of this study. This study was conducted following the principles of the Declaration of Helsinki.

Authors’ contributions

Conceptualization: KWK

Data curation, Visualization: EJJ

Writing–original draft: KWK

Writing–review and editing: All authors

All authors read and approved the final manuscript.

Conflict of interest

All authors have no conflicts of interest to declare.

Funding/support

None.

Data availability

The data presented in this study are available on request from the corresponding author.

Supplementary materials

Supplementary materials can be found via https://doi.org/10.7602/jmis.2024.27.2.114.