Augmented Reality and Image-Guided Robotic Liver Surgery

Artificial intelligence makes surgical resection easier and safer, and, at the same time, can improve oncological results. The robotic system fits perfectly with these more or less diffused technologies, and it seems that this benefit is mutual. In liver surgery, robotic systems help surgeons to localize tumors and improve surgical results with well-defined preoperative planning or increased intraoperative detection. Furthermore, they can balance the absence of tactile feedback and help recognize intrahepatic biliary or vascular structures during parenchymal transection. Some of these systems are well known and are already widely diffused in open and laparoscopic hepatectomies, such as indocyanine green fluorescence or ultrasound-guided resections, whereas other tools, such as Augmented Reality, are far from being standardized because of the high complexity and elevated costs. In this paper, we review all the experiences in the literature on the use of artificial intelligence systems in robotic liver resections, describing all their practical applications and their weaknesses.

Three-Device (3D) Technique for Liver Parenchyma Dissection in Robotic Liver Surgery

Background: The implementation of robotics in liver surgery offers several advantages compared to conventional open and laparoscopic techniques. One major advantage is the enhanced degree of freedom at the tip of the robotic tools compared to laparoscopic instruments. This enables excellent vessel control during inflow and outflow dissection of the liver. Parenchymal transection remains the most challenging part during robotic liver resection because currently available robotic instruments for parenchymal transection have several limitations and there is no standardized technique as of yet. We established a new strategy and share our experience. Methods: We present a novel technique for the transection of liver parenchyma during robotic surgery, using three devices (3D) simultaneously: monopolar scissors and bipolar Maryland forceps of the robot and laparoscopic-guided waterjet. We collected the perioperative data of twenty-eight patients who underwent this procedure for minor and major liver resections between February 2019 and December 2020 from the Magdeburg Registry of minimally invasive liver surgery (MD-MILS). Results: Twenty-eight patients underwent robotic-assisted 3D parenchyma dissection within the investigation period. Twelve cases of major and sixteen cases of minor hepatectomy for malignant and non-malignant cases were performed. Operative time for major liver resections (≥ 3 liver segments) was 381.7 (SD 80.6) min vs. 252.0 (70.4) min for minor resections (p < 0.01). Intraoperative measured blood loss was 495.8 (SD 508.8) ml for major and 256.3 (170.2) ml for minor liver resections (p = 0.090). The mean postoperative stay was 13.3 (SD 11.1) days for all cases. Liver surgery-related morbidity was 10.7%, no mortalities occurred. We achieved an R0 resection in all malignant cases. Conclusions: The 3D technique for parenchyma dissection in robotic liver surgery is a safe and feasible procedure. This novel method offers an advanced locally controlled preparation of intrahepatic vessels and bile ducts. The combination of precise extrahepatic vessel handling with the 3D technique of parenchyma dissection is a fundamental step forward to the standardization of robotic liver surgery for teaching purposing and the wider adoption of robotic hepatectomy into routine patient care.

Laparoscopic Anatomical Resection of Liver Segment 8 via a Hepatic Parenchymal Transection-first Approach Guided by the Middle Hepatic Vein

Background Although recent technological developments and improved endoscopic procedures have further extended the application of laparoscopic liver resection, pure laparoscopic anatomic resection of liver segment 8 (S8) is still rarely performed due to the lack of an appropriate surgical approach. This article discusses the technical tips and operation methods for laparoscopic anatomical resection of liver S8 via a hepatic parenchymal transection-first approach.Methods Clinical data of 14 patients who underwent laparoscopic anatomical resection of liver segment 8 via a hepatic parenchymal transection-first approach guided by the middle hepatic vein (MHV) in the Second Affiliated Hospital, Third Military Medical University (Army Medical University) from May 2017 to December 2019 were retrospectively analyzed. The operation time, intraoperative blood loss, postoperative complications, and hospitalization duration were observed.Results The operation was successful with no complications. No other abnormality was noted during outpatient follow-up examination.Conclusions Laparoscopic anatomical resection of liver S8 is still quite challenging at present, and it is our goal to design a reasonable procedure with accurate efficacy and high safety. We use hepatic parenchymal transection-first approach guided by the MHV for laparoscopic anatomical resection of liver S8. This technique overcomes the problem of high technical risk, greatly reduces the surgical difficulty and achieves technological breakthroughs, but there are still many problems worth further exploration.

How-I-do-it: laparoscopic left medial sectionectomy utilizing a cranial approach to the middle hepatic vein and Laennec’s capsule

Background Laparoscopic anatomic liver resection is technically demanding, given the need to safely isolate the Glissonean pedicles and expose the hepatic veins (HVs) on the liver parenchyma cut surface. Laennec’s capsule is observed around the Glissonean pedicles and root of the HVs. However, its existence, particularly on the peripheral side of the HVs, remains controversial. Herein, we describe Laennec’s capsule-related histopathological findings around the HVs and a safe laparoscopic left medial sectionectomy utilizing Laennec’s capsule. Methods The extrahepatic Glissonean approach was performed by connecting Gates II and III, in accordance with Sugioka’s Gate theory. Liver parenchymal transection commenced along the demarcation line, which is between the medial and lateral sections, and the G4 was dissected during transection. Subsequently, via the outer-Laennec approach, the middle hepatic vein (MHV) was exposed from the root side in cranial view, while Laennec’s capsule was preserved. Parenchymal transection was completed while connecting the MHV with the demarcation line. We obtained the membrane surrounding the HVs and performed histopathological examinations. Results Six patients underwent laparoscopic left medial sectionectomy from February 2012 to November 2020. There were no cases involving complications (Clavien–Dindo classification; grade II or higher), open-surgery conversion, transfusion, or surgery-related death. The histopathological findings showed Laennec’s capsule surrounding both the trunk of the major HVs and the peripheral side of the HVs. Conclusions A cranial approach to the major HVs utilizing Laennec’s capsule is a feasible and advantageous procedure for laparoscopic left medial sectionectomy. We propose that Laennec’s capsule surrounds the entire length of the HVs.

Feasibility of Microwave-Based Scissors and Tweezers in Partial Hepatectomy: An Initial Assessment on Canine Model

Purpose: This study aimed to assess the feasibility of partial hepatectomy (PH) simplified by using microwave-based devices in animal experiments.Methods: PH was performed on 16 beagles using either Acrosurg Scissors (AS) or Acrosurg Tweezers (AT) without hepatic pedicle (HP) control. Parenchymal transection time, Glissonean pedicle (GP) seal time, bleeding volume, bile leak, and burst pressure were recorded. Probable complications were investigated after 4 weeks.Results: Transection time (6.5 [6.0–7.6] vs. 11.8 [10.5–20.2] min, p &lt; 0.001) with AT were significantly shorter than with AS. GP sealing times (60 [55–60] vs. 57 [46–91] s, p = 0.859) by both devices were nearly similar. Bleeding volume in the AT group was approximately one-fourth of that in the AS group (6.7 [1.4–22] vs. 28.8 [5.8–48] mL, p = 0.247). AT created higher burst pressure on the bile duct stumps (p = 0.0161). The two devices did not differ significantly in morbidity and mortality after four-week follow-up.Conclusion: Acrosurg devices achieved a safe PH without HP control owing to microwave-based sealing. AS could be used alone in PH, whereas the clamp-crushing function of AT seemed more advantageous in reducing the transection time and blood loss.

Liver transection with pre-coagulation therapy in liver cirrhosis ~ Effective usage of an energy device at hepatectomy ~

Hepatectomy for liver cirrhosis patients requires skillful surgical technique and careful attention caused by the fibrotic parenchyma, elevated portal pressure, and impaired coagulation. This report evaluated short- and long-term outcomes for liver cirrhosis patients receiving pre-coagulation therapy on the parenchymal transection plane, as compared to non-coagulation cases. 73 patients diagnosed with cirrhosis via post-operative pathological findings were selected upon reviewing 887 hepatectomy patient files. They were divided into a pre-coagulation group (n=20) and a non-coagulation group (n=53). There were no significant differences in patient and tumor factors between two groups. Pre-coagulation group had significantly less blood loss compared with non-coagulation group [282 vs 563g (p &lt; 0.05)], shorter operative time [214 vs 276min (p = 0.06)], and shorter postoperative hospital stays [14.5 vs 22.5 days (p = 0.12)]. The median recurrence free survival rates time in the pre-coagulation group (733 days) was significantly longer than that in the non-coagulation group (400 days) (p &lt; 0.05). Overall survival rates showed rates showed no difference among the two groups (p = 0.62). Pre-coagulation therapy may be one of the a preferred treatment application for hepatectomy patients with severe liver fibrosis.