Laparoscopic Liver Resection Research Articles

Features of laparoscopic liver resection training after mastering of robot-assisted technology

Aim. To estimate the learning curve for laparoscopic liver resections performed by a surgeon experienced in robot-assisted liver resections using the CUSUM method. Materials and methods. The study involved a retrospective analysis of the results of laparoscopic liver resections for malignant and benign neoplasms performed from 2015 to December 2020 and robot-assisted liver resections from 2010 to 2020. The author evaluated the learning curve for laparoscopic liver resections of a surgeon who had mastered robot-assisted resections of high difficulty. Selecting the boundaries between training periods according to the obtained CUSUM graphs was determined by critical changes in the resection difficulty score (IWATE and IMM), duration of surgery, blood loss, and incidence of postoperative complications. Major perioperative events were compared between the laparoscopic and robot-assisted resection groups in each of the training periods. Results. 174 laparoscopic and 57 robot-assisted liver resections were performed. The duration of the first training period comprised 11 robot-assisted resections and 20 laparoscopic resections, the second period – 16 and 20, the third period – 30 and 134, accordingly. In the second period, the resection difficulty score increased significantly for both groups, while the amount of blood loss, the incidence of postoperative complications, and the duration of hospital treatment did not differ significantly. In the second training period, the duration of surgery was significantly longer in both groups. Conclusion. Studying the dynamics of surgical difficulty using the CUSUM method is considered to be a reliable, controlled way to estimate the learning curve for liver resection. Completing the learning curve for robot-assisted liver resections reduces the duration of the learning curve for laparoscopic resections compared to published data of other authors.

Laparoscopic liver resection is superior to radiofrequency ablation for small hepatocellular carcinoma: a systematic review and meta-analysis of propensity score-matched studies.

The approach in small hepatocellular carcinoma (HCC) is controversial, no prospective randomized trials to compare ablative or surgical approaches. We compared the surgical and oncological outcomes after laparoscopic hepatectomy (LH) and radiofrequency ablation (RFA) in small HCC patients based on matched cohort studies that performed propensity score matching (PSM). We systemically searched the PubMed, Cochrane Library, Embase, Web of Science, and the Chinese BioMedical Literature (CBM) databases. All published propensity score-matched studies that compared LH and RFA for small HCC were included in this study. Eight studies with a total of 1273 small HCC cases were included. The results of the meta-analysis revealed that there was no significant difference in the 1- year overall survival (OS) rate between the two groups, whereas the LH group had significantly higher 3- year overall survival rate (RR = 1.14, 95% CI 1.08-1.20, p < 0.00001) as well as 1- and 3-year disease-free survival (DFS) rates (RR = 1.31, 95% CI 1.22-1.42, p < 0.00001; RR = 1.66, 95% CI 1.46-1.90, p < 0.00001) than the RFA group. Meanwhile, the local recurrence rate and intrahepatic distant recurrence rate were significantly lower in the LH group than in the RFA group (RR = 0.29, 95% CI 0.20-0.42, p < 0.00001; RR = 0.67, 95% CI 0.49-0.92, p = 0.01). In comparison with the LH group, the RFA group had a lower incidence of overall and major postoperative complications (RR = 1.81, 95% CI 1.47-2.24, p < 0.00001; RR = 2.76, 95% CI 1.48-5.12, p = 0.001), but there was no significant difference in postoperative mortality between the two groups. In addition, further comparison of single postoperative complications showed that the incidence of ascites was lower in the RFA group than in the LH group (RR = 3.62, 95% CI 1.64-7.96, p = 0.001), whereas there was no significant difference in the incidence of postoperative bleeding, abdominal infection and bile leakage between the two groups (RR = 3.50, 95% CI 0.74-16.61, p = 0.11; RR = 5.00, 95% CI 0.59-42.23, p = 0.14; RR = 4.00, 95% CI 0.45-35.23, p = 0.21). Besides, the hospital stay was shorter in the RFA group than in the LH group (MD = 4.29, 95% CI 2.06-6.53, p = 0.0002). Our meta-analysis demonstrated that in comparison with RFA in the treatment of small HCC, LH provided superior long-term OS and DFS together with lower rates of local and intrahepatic distant recurrence after surgery. However, RFA was associated with better short-term outcomes.

Robotic Versus Laparoscopic Liver Resection in Various Settings: An International Multicenter Propensity Score Matched Study of 10.075 Patients.

To compare the perioperative outcomes of robotic liver surgery (RLS) and laparoscopic liver surgery (LLS) in various settings. Clear advantages of RLS over LLS have rarely been demonstrated, and the associated costs of robotic surgery are generally higher than those of laparoscopic surgery. Therefore, the exact role of the robotic approach in minimally invasive liver surgery remains to be defined. In this international retrospective cohort study, the outcomes of patients who underwent RLS and LLS for all indications between 2009 and 2021 in 34 hepatobiliary referral centers were compared. Subgroup analyses were performed to compare both approaches across several types of procedures: (1) minor resections in the anterolateral (2, 3, 4b, 5, and 6) or (2) posterosuperior segments (1, 4a, 7, 8), and (3) major resections (≥3 contiguous segments). Propensity score matching was used to mitigate the influence of selection bias. The primary outcome was textbook outcome in liver surgery (TOLS), previously defined as the absence of intraoperative incidents ≥grade 2, postoperative bile leak ≥grade B, severe morbidity, readmission, and 90-day or in-hospital mortality with the presence of an R0 resection margin in case of malignancy. The absence of a prolonged length of stay was added to define TOLS+. Among the 10.075 included patients, 1.507 underwent RLS and 8.568 LLS. After propensity score matching, both groups constituted 1.505 patients. RLS was associated with higher rates of TOLS (78.3% vs 71.8%, P < 0.001) and TOLS+ (55% vs 50.4%, P = 0.026), less Pringle usage (39.1% vs 47.1%, P < 0.001), blood loss (100 vs 200 milliliters, P < 0.001), transfusions (4.9% vs 7.9%, P = 0.003), conversions (2.7% vs 8.8%, P < 0.001), overall morbidity (19.3% vs 25.7%, P < 0.001), and microscopically irradical resection margins (10.1% vs. 13.8%, P = 0.015), and shorter operative times (190 vs 210 minutes, P = 0.015). In the subgroups, RLS tended to have higher TOLS rates, compared with LLS, for minor resections in the posterosuperior segments (n = 431 per group, 75.9% vs 71.2%, P = 0.184) and major resections (n = 321 per group, 72.9% vs 67.5%, P = 0.086), although these differences did not reach statistical significance. While both produce excellent outcomes, RLS might facilitate slightly higher TOLS rates than LLS.

Efficacy of surgical staple line reinforcement in Glissonean stapling: A single-center pilot study.

Vascular staplers are routinely used in laparoscopic liver resection, which has become a standard procedure in advanced medical facilities. Although previous reports have outlined the benefits of staple line reinforcement (SLR), its application in Glissonean pedicle transection during hepatic resection remains poorly studied. This study investigated surgical SLR as a tool to enhance staple line strength and improve perioperative hemostasis. Here, 10 patients who underwent laparoscopic liver resection using the Tri-StapleTM2.0 Reinforced Reload were included. Patient characteristics, surgical details, and outcomes were assessed. The results demonstrated successful outcomes with no complications related to bile leakage or injuries during staple insertion. Overall, our findings suggest that SLR can be safely utilized in Glissonean pedicle transection during laparoscopic liver resections. Further studies are required to comprehensively evaluate its benefits compared with conventional surgical staplers.

Incidence of incisional hernia following liver surgery for colorectal liver metastases. Does the laparoscopic approach reduce the risk? A comparative study.

No reports to compare incisional hernia (IH) incidence between laparoscopic and open colorectal liver metastases (CRLM) resections have previously been made. This is the first comparative study. Single-center retrospective review of patients who underwent CRLM surgery between January 2011 and December 2018. IH relating to liver surgery was confirmed by computed tomography. Patients were divided into laparoscopic liver resection (LLR) and open liver resection (OLR) groups. Data collection included age, sex, presence of diabetes mellitus, steroid intake, history of previous hernia or liver resection, subcutaneous and peri-renal fat thickness, preoperative creatinine and albumin, American Society of Anesthesiologists (ASA) score, major liver resection, surgical site infection, synchronous presentation, and preoperative chemotherapy. Two hundred and forty-seven patients were included with a mean follow-up period of 41 ± 29 months (mean ± standard deviation). Eighty seven (35%) patients had LLR and 160 patients had OLR. No significant difference in the incidence of IH between LLR and OLR was found at 1 and 3 years, respectively ([10%, 19%] vs. [10%, 19%], p = 0.95). On multivariate analysis, previous hernia history (hazard ratio [HR], 2.22; 95% confidence interval [CI], 1.56-4.86) and subcutaneous fat thickness (HR, 2.22; 95% CI, 1.19-4.13) were independent risk factors. Length of hospital stay was shorter in LLR (6 ± 4 days vs. 10 ± 8 days, p < 0.001), in comparison to OLR. In CRLM, no difference in the incidence of IH between LLR and OLR was found. Previous hernia and subcutaneous fat thickness were risk factors. Further studies are needed to assess modifiable risk factors to develop IH in LLR.

Comparison between laparoscopic liver resection and open liver resection in patients with hepatocellular carcinoma with portal vein tumor thrombosis.

Recently, the outcomes of surgical treatment for advanced hepatocellular carcinoma (HCC) have improved. However, despite the technical advancements in laparoscopic liver resection (LLR), it is still not recommended as the standard treatment for HCC with portal vein tumor thrombosis (PVTT) because of the poor oncological outcomes. This study aims to compare the clinical outcomes of open liver resection (OLR) and LLR in patients with HCC with PVTT. A total of 86 patients with PVTT confirmed in the pathological report between January 2014 and December 2018, were enrolled. Short-term, postoperative, and long-term outcomes, including recurrence-free survival and overall survival rates, were evaluated. No difference between the two groups, except for age, was detected. The median age in the laparoscopic group was significantly higher than that in the open group. Regarding the pathological features, the maximal tumor size was significantly larger in the OLR; other pathological factors did not differ. There was no significant difference between overall survival (OS) and recurrence-free survival (RFS). Vp3 PVTT (hazards ratio [HR] 6.1, 95% confidence interval [CI] 1.9-18.5), Edmondson grade IV (HR 4.7, 95% CI 1.7-12.9, p = 0.003), and intrahepatic metastasis (HR 3.9, 95% CI 2.1-7.2, p < 0.001) remained the unique independent predictors of recurrence-free survival according to a multivariate Cox proportional hazard regression analysis. Laparoscopic liver resection for the management of HCC with PVTT provides the same short- and long-term results as those of the open approach.

Short-term outcomes of laparoscopic extended hepatectomy versus major hepatectomy: a single-center experience

IntroductionLaparoscopic major hepatectomy (LMH) remains restricted to a few specialized centers and poses a challenge to surgeons performing laparoscopic resections. Laparoscopic extended resections are even more complex and rarely conducted. MethodsFrom a single-institution database, we compared the short-term outcomes of patients who underwent major and extended laparoscopic resections, stratifying the entire retrospective cohort into four groups: right hepatectomy, left hepatectomy, right extended hepatectomy, and left extended hepatectomy. Patient demographics, tumor characteristics, operative variables, and especially postoperative outcomes were evaluated. Results250 patients underwent major and extended laparoscopic liver resections, including 160 right, 31 right extended, 36 left, and 23 left extended laparoscopic hepatectomies. The most common indication for resection was colorectal liver metastases (64%). Laparoscopic extended hepatectomy (LEH) showed significantly longer operative time, more blood loss, need for Pringle maneuver, conversion to open surgery, higher rates of liver failure, postoperative ascites, and intra-abdominal hemorrhage, R1 margins and length of stay when compared with the LMH group. Mortality rates were similar between groups. Multivariate analysis revealed intraoperative blood transfusion (OR = 5.1[CI-95%: 1.15–6.79]; p = 0.02) as an independent predictor for major complications. ConclusionsLEH showed to be feasible, however with higher blood loss and significantly associated to major complications.

Safety and Feasibility of Laparoscopic Liver Resection with the Clamp-Crush Method Using the BiSect.

Various energy devices are available for resection of the liver parenchyma during laparoscopic liver resection (LLR). We have historically performed liver resections using the Cavitron Ultrasonic Surgical Aspirator (CUSA). More recently, we have used new bipolar forceps (BiSect; Erbe Elektromedizin GmbH, Tübingen, Germany) to perform clamp-crush dissection with good results. The BiSect is a reusable bipolar forceps with a laparoscopic dissecting forceps tip and both an incision mode and coagulation mode. We evaluated the perioperative clinical course of patients who underwent LLR using the clamp-crush method with the BiSect compared with the CUSA. This single-center case control study involved patients with liver metastasis from colorectal cancer who underwent LLR using either the BiSect or CUSA at our hospital from January 2019 to December 2022. We performed the LLR using CUSA from January 2019 to early October 2020. After introduction of the BiSect in late October 2020, we used BiSect for the LLR. Before surgery, the three-dimensional liver was constructed based on computed tomography images, and a preoperative simulation was performed. We evaluated the results of LLR using the BiSect versus the CUSA and assessed the short-term results of LLR. During the study period, we performed partial liver resection using the BiSect in 26 patients and the CUSA in 16 patients. In the BiSect group, the median bleeding volume was 55 mL, the median operation time was 227 minutes, and the median postoperative length of hospital stay was 9 days. In the CUSA group, the median bleeding volume was 87 mL, the median operation time was 305 minutes, and the median postoperative length of hospital stay was 10 days. There were no statistically significant differences in the clinical course including bile leakage, bile duct stenosis, and post operative hospital stay between the two groups. Compared with LLR using the CUSA, the clamp-crush method using the BiSect in LLR is a safe and useful liver transection technique. Further study should be conducted to clarify whether BiSect is safe and useful in LLR for patients with other tumor types and patients who undergo other procedures.

Achieving Textbook Outcomes after Laparoscopic Resection in Posterosuperior Segments of the Liver: The Impact of the Learning Curve.

Achieving textbook outcomes (TOs) improves the short-term and long-term performance of a hospital. Our objective was to assess TOs in the laparoscopic liver resection (LLR) of tumors in the PS (posterosuperior) section of the liver and identify the impact of the learning curve. We conducted a retrospective cohort study analyzing patients who underwent LLR for lesions located in the PS segments. Patients were divided into a TO and no-TO group. TOs were defined as negative margins, no transfusion, no readmission, no major complications, no 30-day mortality, and a length of stay ≤ 50th percentile. Patients' outcomes were assessed in two study periods before and after 2015. TOs were achieved in 47.6% (n = 117). In multivariable analysis, obesity (p = 0.001), shorter operation time (p < 0.001), less blood loss (p < 0.001), normal albumin (p = 0.003), and minor resection (p = 0.046) were significantly associated with achieving TOs. Although the 5-year recurrence-free survival rate (p = 0.096) was not significantly different, the 5-year overall survival rate was significantly greater in the TO group (p = 0.001). Body mass index > 25 kg/m2 (p = 0.020), age > 65 years (p = 0.049), and achievement of TOs (p = 0.024) were independently associated with survival. The proportion of patients who achieved a TO was higher after 2015 than before 2015 (52.3% vs. 36.1%; p = 0.022). TOs are important markers not only for assessing hospital and surgeon performance but also as predictors of overall survival. As the number of surgeons who achieve the learning curve increases, the number of patients with TOs will gradually increase with a subsequent improvement in overall survival.

Revisiting the Institut Mutualiste Montsouris Difficulty Classification of Laparoscopic Liver Resection with the Data from a Personal Series-Evaluations for the Difficulty of Left Medial Sectionectomy and Length of Hospital Stay.

The IMM (Institut Mutualiste Montsouris) difficulty classification for laparoscopic liver resection is based only on the type of surgical procedure. It is useful for assessing outcomes and setting benchmarks in a group sharing the same indications. There is, however, no left medial sectionectomy in the system. Its difficulty was evaluated using the same methodology as IMM with the data from a personal series. Furthermore, length of hospital stay was evaluated as the representative of short-term outcomes. IMM scores of our right and left hemihepatectomies, right anterior sectionectomy, and segment 7 or 8 segmentectomies are 3. That of left medial sectionectomies is 2, the same as right posterior sectionectomy and segment or less anatomical resections. Those of left lateral sectionectomy and partial resection are 0. The group with a score of 3 was divided into two groups-with and without extended hospital stays (extended only for right hemihepatectomies and right anterior sectionectomies). The difficulty of medial sectionectomy was positioned at the same level as posterior sectionectomy and segment or less anatomical resections. The result from the second evaluation may indicate that there are other factors with an impact on difficulty related to short-term outcomes, other than intraoperative surgical difficulty from the procedure itself.

Low versus standard central venous pressure during laparoscopic liver resection: A systematic review, meta-analysis and trial sequential analysis.

To compare the outcomes of low central venous pressure (CVP) to standard CVP during laparoscopic liver resection. The study design was a systematic review following the PRISMA statement standards. The available literature was searched to identify all studies comparing low CVP with standard CVP in patients undergoing laparoscopic liver resection. The outcomes included intraoperative blood loss (primary outcome), need for blood transfusion, mean arterial pressure, operative time, Pringle time, and total complications. Random- effects modelling was applied for analyses. Type I and type II errors were assessed by trial sequential analysis (TSA). A total of 8 studies including 682 patients were included (low CVP group, 342; standard CVP group, 340). Low CVP reduced intraoperative blood loss during laparoscopic liver resection (mean difference [MD], -193.49 mL; 95% confidence interval [CI], -339.86 to -47.12; p = 0.01). However, low CVP did not have any effect on blood transfusion requirement (odds ratio [OR], 0.54; 95% CI, 0.28-1.03; p = 0.06), mean arterial pressure (MD, -1.55 mm Hg; 95% CI, -3.85-0.75; p = 0.19), Pringle time (MD, -0.99 minutes; 95% CI, -5.82-3.84; p = 0.69), operative time (MD, -16.38 minutes; 95% CI, -36.68-3.39; p = 0.11), or total complications (OR, 1.92; 95% CI, 0.97-3.80; p = 0.06). TSA suggested that the meta-analysis for the primary outcome was not subject to type I or II errors. Low CVP may reduce intraoperative blood loss during laparoscopic liver resection (moderate certainty); however, this may not translate into shorter operative time, shorter Pringle time, or less need for blood transfusion. Randomized controlled trials with larger sample sizes will provide more robust evidence.

Association between Unplanned Conversion and Patient Survival after Laparoscopic Liver Resection for Hepatocellular Carcinoma: A Propensity Score Matched Analysis.

Unplanned conversion (UPC) is considered to be a predictor of poor postoperative outcomes. However, the effects of UPC on the survival of patients with hepatocellular carcinoma (HCC) remain controversial. The aim of this study is to compare the outcomes between patients who underwent laparoscopic liver resection (LLR) and those who underwent UPC for HCC. Among 1029 patients with HCC who underwent hepatectomy between 2004 and 2021, 251 were eligible for the study. Of 251 patients who underwent hepatectomy for HCC in PS segments, 29 (26.0%) required UPC, and 222 underwent LLR. After 1:5 PSM, 25 patients were selected for the UPC group and 125 for the LLR group. Blood loss, transfusion rate, hospital stay, and postoperative complication were higher in the UPC group. Regarding oncologic outcomes, although the 5-year overall survival rate was similar in both groups (p = 0.544), the recurrence-free survival rate was lower in the UPC group (p < 0.001). UPC was associated with poor short-term as well as inferior long-term outcomes compared with LLR for HCC in PS segments. Therefore, surgeons must carefully select patients and consider early conversion if unexpected bleeding occurs to maintain safety and oncologic outcomes.

Liver resection in selective hepatocellular carcinoma with Vp3 or Vp4 portal vein tumor thrombosis improves prognosis.

Hepatocellular carcinoma (HCC) tumor thrombi located in the first branch of the portal vein (Vp3) or in the main portal trunk (Vp4) are associated with poor prognosis. This study aimed to investigate the clinicopathological characteristics and risk factors for HCC recurrence and mortality following liver resection (LR) in patients with Vp3 or Vp4 HCC. The study included 64 patients who underwent LR for HCC with Vp3 or Vp4 portal vein tumor thrombosis (PVTT). Fifty-eight patients (90.6%) had Vp3 PVTT, whereas the remaining six patients exhibited Vp4 PVTT. The median tumor size measured 8 cm, with approximately 36% of patients presented with multiple tumors. Fifty-four patients (84.4%) underwent open LR, whereas 10 patients underwent laparoscopic LR. In the Vp4 cases, combined LR and tumor thrombectomy were performed. The 3-year cumulative disease-free survival rate was 42.8% for the Vp3 group and 22.2% for the Vp4 group. The overall survival (OS) rate at 3 years was 47.9% for the Vp3 group and 60.0% for the Vp4 group. Intrahepatic metastasis has been identified as an important contributor to HCC recurrence. High hemoglobin levels are associated with high mortality. LR is a safe and effective treatment modality for selected patients with Vp3 or Vp4 HCC PVTT. This suggests that LR is a viable option for these patients, with favorable outcomes in terms of OS.

Concomitant training in robotic and laparoscopic liver resections of low-to-intermediate difficulty score: a retrospective analysis of the learning curve

In the setting of minimally invasive liver surgery (MILS), training in robotic liver resections (RLR) usually follows previous experience in laparoscopic liver resections (LLR). The aim of our study was to assess the learning curve of RLR in case of concomitant training with LLR. We analyzed consecutive RLRs and LLRs by a surgeon trained simultaneously in both techniques (Surg1); while a second surgeon trained only in LLRs was used as control (Surg2). A regression model was used to adjust for confounders and a Cumulative Sum (CUSUM) analysis was carried out to assess the learning phases according to operative time and difficulty of the procedures (IWATE score). Two-hundred-forty-five procedures were identified (RobSurg1, n = 75, LapSurg1, n = 102, LapSurg2, n = 68). Mean IWATE was 4.0, 4.3 and 5.8 (p < 0.001) in each group. The CUSUM analysis of the adjusted operative times estimated the learning phase in 40 cases (RobSurg1), 40 cases (LapSurg1), 48 cases (LapSurg2); for IWATE score it was 38 cases (RobSurg1), 33 cases (LapSurg1), 38 cases (LapSurg2) respectively. Our preliminary experience showed a similar learning curve of 40 cases for low and intermediate difficulty RLR and LLR. Concomitant training in both techniques was safe and may be a practical option for starting a MILS program.

Laparoscopic liver resection versus radiofrequency ablation for caudate lobe solitary hepatocellular carcinoma: A propensity score matching study.

This study aimed to compare the clinical efficacy of laparoscopic liver resection (LLR) and radiofrequency ablation (RFA) in treating solitary hepatocellular carcinoma (HCC) of the hepatic caudate lobe. Patients with hepatic caudate lobe HCC who underwent LLR or RFA at three hospitals in China between February 2015 and February 2021 were included. In total, 112 patients met the inclusion criteria, of whom 52 underwent RFA and 60 underwent LLR. The outcomes of the two groups were compared and analyzed using propensity score matching (PSM) method. There were no significant differences between the two groups in terms of sex, HBV/HCV positivity, AFP positivity (>100 ng/mL), tumor position, Child-Pugh score, or preoperative liver function tests (ALT, AST, TBIL, ALB, and PT) (p > 0.05). Compared to the LLR group, the RFA group had a shorter operation time, less intraoperative bleeding, and shorter postoperative hospital stay (p < 0.05). There was no statistically significant difference in overall postoperative complications between the two groups (p > 0.05). Despite the larger tumor size, the LLR group had better postoperative recurrence-free survival (RFS) (p = 0.00027) and overall survival (OS) (p = 0.0023) than the RFA group. After one-to-one PSM, 31 LLR patients and 31 RFA patients were selected for further analyses. The advantages of LLR over RFA were observed in terms of RFS (p < 0.0001) and OS (p = 0.00029). LLR should probably be recommended as the preferred method for solitary caudate lobe HCC.

A case of laparoscopic hepatic S4 partial resection after coronary artery bypass grafting using the right gastroepiploic artery

AbstractLaparoscopic liver resection has become safer over time, making it a viable option for patients previously considered high‐risk. We discuss a case in which a 73‐year‐old man underwent laparoscopic liver resection after coronary artery bypass grafting using the right gastroepiploic artery (RGEA). The patient was noted to have liver metastases of rectal cancer in the medial segment. Laparoscopic hepatic S4 partial resection was done after preoperative assessment of the RGEA graft pathway by computed tomography. During the operation, the RGEA graft was adherent to the dorsal surface of the liver, but the laparoscopic approach allowed fine dissection. The tumor was then safely removed, and the patient was discharged without complications. Preoperative assessment of the graft pathway is necessary because of the lack of tactile sensation during laparoscopic surgery. However, a magnified view of the laparoscope enabled us to perform fine dissection to avoid injury to the graft vessels.

A novel image-guided laparoscopic liver resection with integrated fluorescent imaging and artificial intelligence: A preliminary study.

568 Background: Technology innovations improve surgical techniques. ICG fluorescence imaging is beneficial for real time navigation tool during surgery and enables accurate surgery. Recently, the prediction of anatomical structures by artificial intelligence (AI) is expected to support surgeons as navigation tool. We developed a visual-support AI system to perform the laparoscopic liver resection (LLR) using ICG fluorescence imaging and AI technology. Methods: Procedure: ICG fluorescence imaging was used for liver mapping and securing surgical margin. AI model development and evaluation: Over 430 images extracted from 13 videos of LLR for hepatocellular carcinoma and colorectal liver metastasis was used to develop and evaluate the AI algorithm at Anaut Inc. The annotation was performed on video frames capturing a LLR performed by 2 surgeons for hepatic vein and Glisson sheath. The performance of AI on unlearned LH videos was evaluated quantitatively using Intersection-Over-Union (IOU) and Dice coefficients, and qualitatively on a five-point scale (from 1 to 5) by 10 hepato-biliary-pancreatic surgeons using 35 randomly extracted still images from the analyzed videos. Results: ICG fluorescence imaging could visualize the demarcation line and clarified the boundaries of the liver transected surface. The hepatic veins and Glisson sheath were appeared in the parenchymal transection plane during segmentectomy and securing surgical margin, and this AI system enabled to recognize and display these vascular structures through color-coding under bleeding and ICG fluorescent imaging without visual discrepancies. The AI model accurately recognized vascular structures of any size (IoU=0.33, Dice=0.44) in real-time (&lt;0.12 s) In the qualitative evaluation by surgeons, the mean sensitivity score was 4.10 ± 0.92 (range 3.61–4.76). Additionally, this AI system also recognized vascular structures during robot-assisted liver resection. Conclusions: This is the first study demonstrating that AI can precisely identify vascular structures during LLR. Novel image-guided LLR using ICG fluorescent imaging and artificial intelligence is expected to provide safer and more accurate LLR, thereby contributing to reduce complications and improve survival rates.

Laparoscopic anatomic vs. nonanatomic liver resection for large hepatocellular carcinoma (≥5 cm) in the right lobe

ObjectiveTo determine the impacts and outcomes of laparoscopic anatomic liver resection (LAR) and laparoscopic nonanatomic resection (LNAR) in patients with large hepatocellular carcinoma (HCC) in the right lobe of the liver. BackgroundThere are few comparative studies of LAR and LNAR for large HCC. MethodThree hundred thirty-seven patients underwent liver resection for large HCC (≥5 cm) at Seoul National University Bundang Hospital, Seoul, Korea, between January 2004 and December 2022. After the exclusion of patients treated with open hepatic resection and those who had left-lobe or bilobar tumors, 94 patients were ultimately included. Patients were divided into LAR group (61 patients) and LNAR group (33 patients). After propensity score matching (PSM) with 1:1 matching, 31 patients were included in each group. The outcomes in the two groups were compared. ResultsLAR group had longer operative time than LNAR group (333.7 ± 113.7 vs 210 ± 117.6 min, respectively, P < 0.001), wider safety margin (1.4 ± 1.5 vs 0.7 ± 0.7 cm, respectively, P = 0.015), and lower incidence of recurrence (25.8% vs. 54.8%, respectively, P = 0.021). ConclusionLAR required longer operative time, achieved wider safety margin, and had lower incidence of recurrence than LNAR.

Intraoperative artificial intelligence system identifying liver vessels in laparoscopic liver resection: a retrospective experimental study.

The precise recognition of liver vessels during liver parenchymal dissection is the crucial technique for laparoscopic liver resection (LLR). This retrospective feasibility study aimed to develop artificial intelligence (AI) models to recognize liver vessels in LLR, and to evaluate their accuracy and real-time performance. Images from LLR videos were extracted, and the hepatic veins and Glissonean pedicles were labeled separately. Two AI models were developed to recognize liver vessels: the "2-class model" which recognized both hepatic veins and Glissonean pedicles as equivalent vessels and distinguished them from the background class, and the "3-class model" which recognized them all separately. The Feature Pyramid Network was used as a neural network architecture for both models in their semantic segmentation tasks. The models were evaluated using fivefold cross-validation tests, and the Dice coefficient (DC) was used as an evaluation metric. Ten gastroenterological surgeons also evaluated the models qualitatively through rubric. In total, 2421 frames from 48 video clips were extracted. The mean DC value of the 2-class model was 0.789, with a processing speed of 0.094s. The mean DC values for the hepatic vein and the Glissonean pedicle in the 3-class model were 0.631 and 0.482, respectively. The average processing time for the 3-class model was 0.097s. Qualitative evaluation by surgeons revealed that false-negative and false-positive ratings in the 2-class model averaged 4.40 and 3.46, respectively, on a five-point scale, while the false-negative, false-positive, and vessel differentiation ratings in the 3-class model averaged 4.36, 3.44, and 3.28, respectively, on a five-point scale. We successfully developed deep-learning models that recognize liver vessels in LLR with high accuracy and sufficient processing speed. These findings suggest the potential of a new real-time automated navigation system for LLR.

Comparative study of operative expenses: robotic vs. laparoscopic vs. open liver resections at a university hospital in the UK.

Robotic liver resections (RLR) are increasingly being performed and has previously been considered more costly. The aim is to explore the cost of RLR compared with laparoscopic and open liver resection in a single National Health Service (NHS) hospital. A retrospective review of patients who underwent RLR, LLR, and OLR from April 2014 to December 2022 was conducted. The primary outcomes were the cost of consumables and median income, and the secondary outcomes were the overall length of stay and mortality at 90days. Overall, 332 patients underwent liver resections. There were 204 males (61.4%) and 128 females (38.6%), with a median age of 62years (IQR: 51-77years). Of these, 60 patients (18.1%) underwent RLR, 21 patients (6.3%) underwent LLR, and 251 patients (75.6%) underwent OLR. Median consumables cost per case was £3863 (IQR: £3458-£5061) for RLR, £4326 (IQR: £4273-£4473) for LLR, and £4,084 (IQR: £3799-£5549) for the OLR cohort (p = 0.140). Median income per case was £7999 (IQR: £4509-£10,777) for RLR, £7497 (IQR: £2407-£14,576) for LLR, and £7493 (IQR: £2542-£14,121) for OLR. The median length of stay (LOS) for RLR was 3days (IQR: 2-4.7days) compared to 5days for LLR (IQR: 4.5-7days) and 6days for OLR (IQR: 5-8days, p < 0.001). Within the NHS, RLR has consumable costs comparable to OLR and LLR. It is also linked with a shorter LOS and generates similar income for patients undergoing OLR and LLR.