Comparing a virtual reality head-mounted display to on-screen three-dimensional visualization and two-dimensional computed tomography data for training in decision making in hepatic surgery: a randomized controlled study.

OBJECTIVE: Evaluation of the benefits of a virtual reality (VR) environment with a head-mounted display (HMD) for decision-making in liver surgery. BACKGROUND: Training in liver surgery involves appraising radiologic images and considering the patient's clinical information. Accurate assessment of 2D-tomography images is complex and requires considerable experience, and often the images are divorced from the clinical information. We present a comprehensive and interactive tool for visualizing operation planning data in a VR environment using a head-mounted-display and compare it to 3D visualization and 2D-tomography. METHODS: Ninety medical students were randomized into three groups (1:1:1 ratio). All participants analyzed three liver surgery patient cases with increasing difficulty. The cases were analyzed using 2D-tomography data (group "2D"), a 3D visualization on a 2D display (group "3D") or within a VR environment (group "VR"). The VR environment was displayed using the "Oculus Rift ™" HMD technology. Participants answered 11 questions on anatomy, tumor involvement and surgical decision-making and 18 evaluative questions (Likert scale). RESULTS: Sum of correct answers were significantly higher in the 3D (7.1 ± 1.4, p < 0.001) and VR (7.1 ± 1.4, p < 0.001) groups than the 2D group (5.4 ± 1.4) while there was no difference between 3D and VR (p = 0.987). Times to answer in the 3D (6:44 ± 02:22 min, p < 0.001) and VR (6:24 ± 02:43 min, p < 0.001) groups were significantly faster than the 2D group (09:13 ± 03:10 min) while there was no difference between 3D and VR (p = 0.419). The VR environment was evaluated as most useful for identification of anatomic anomalies, risk and target structures and for the transfer of anatomical and pathological information to the intraoperative situation in the questionnaire. CONCLUSIONS: A VR environment with 3D visualization using a HMD is useful as a surgical training tool to accurately and quickly determine liver anatomy and tumor involvement in surgery.

Impact of virtual reality education on disease-specific knowledge and anxiety for hepatocellular carcinoma patient scheduled for liver resection: a randomized controlled study.

PURPOSE: Hepatocellular carcinoma (HCC) is a significant health concern, and the complexity of liver anatomy poses challenges in conveying radiologic findings and surgical plans to patients. This study aimed to evaluate the impact of a virtual reality (VR) education program on anxiety and knowledge in HCC patients undergoing hepatic resection. METHOD: From 1 January 2022 to 28 February 2023, 88 patients were enrolled in a randomized controlled trial, divided into the VR group ( n =44) and the control group ( n =44). The VR group received patient-specific 3D liver model education through a VR platform, while the control group underwent conventional explanation processes. Both groups completed preintervention and postintervention questionnaires assessing anxiety (using STAI-X-1, STAI-X-2, and VAS) and knowledge about liver resection. Comparison of the questionnaires were performed between the two groups. Multivariable logistic regression was performed to analyze factor related to decrease in anxiety. RESULT: While there was no significant difference in preintervention anxiety and knowledge scores between the two groups, the VR group exhibited significant reduction in STAI-X-1 scores (-4.14±7.5) compared to the control group (-0.84±5.7, P =0.023), as well as knowledge scores (17.20±2.6) compared to the control group (13.42±3.3, P <0.001). In the multivariable logistic regression model, VR education showed significant impact on decrease in STAI-X-1 score, postintervention. (OR=2.902, CI=1.097-7.674, P =0.032). CONCLUSION: The VR education program significantly improved knowledge and reduced anxiety among HCC patients compared to conventional methods. This study suggests that VR can be a valuable tool in patient education, enhancing comprehension and alleviating presurgical anxiety.

An Ex Situ Cadaver Liver Training Model Continuously Pressurized to Simulate Specific Skills Involved in Laparoscopic Liver Resection: the Lap-Liver Trainer.

BACKGROUND: Laparoscopic liver resection (LLR) requires delicate skills. The aim of the study was to develop a training model mimicking as much as possible intraoperative bleeding and bile leakage during LLR. We also assessed the educational value of the training model. METHODS: The Lap-liver trainer (LLT) combined a continuously pressurized ex situ cadaver liver and a customized mannequin. The customized mannequin was designed by computer-aided design and manufactured by 3D printing. The left lateral sectionectomy (LLS) was chosen to assess the feasibility of a LLR with the LLT. Eighteen volunteers were recruited to perform LLS and to assess the educational value of the LLT using a Likert scale. RESULTS: The customized mannequin consisted of a close laparoscopic training device based on a simplified reconstruction of the abdominal cavity in laparoscopic conditions. Ex situ cadaver livers were pressurized to simulate blood and bile supplies. Each expert surgeon (n = 3) performed two LLS. They were highly satisfied of simulation conditions (4.80 ± 0.45) and strongly recommended that the LLT should be incorporated into a teaching program (5.00 ± 0.0). Eight novice and 4 intermediate surgeons completed a teaching program and performed a LLS. Overall, the level of satisfaction was high (4.92 ± 0.29), and performing such a procedure under simulation conditions benefited their learning and clinical practice (4.92 ± 0.29). CONCLUSIONS: The LLT could provide better opportunities for trainees to acquire and practice LLR skills in a more realistic environment and to improve their ability to deal with specific events related to LLR.

A Retrospective, Single-Centre Study on the Learning Curve for Liver Tumor Open Resection in Patients with Hepatocellular Cancers and Intrahepatic Cholagangiocarcinomas.

BACKGROUND: Liver resections have become the first-line treatment for primary malignant tumors and, therefore, are considered a core aspect of surgical training. This study aims to evaluate the learning curve for the safety of open hemihepatectomy procedures for patients suffering from hepatocellular carcinoma (HCC) or intrahepatic cholangiocarcinoma (ICC). METHODS: This single tertiary center retrospective analysis includes 81 consecutive cases of right or left hemihepatectmy. A cumulative sum (CUSUM) control chart was used to investigate the learning curve. RESULTS: The CUSUM curve for operative time and blood loss level peaked at the 29th and 30th case, respectively. The CUSUM curve for minor adverse effects (mAEs) and severe adverse effects (sAEs) showed a downward slope after the 27th and 36th procedures; the curve, however, remained within the acceptable range throughout the entire study. CONCLUSION: When performing open hemihepatectomies in patients with HCC and ICC, the stabilization of the operative time and intraoperative blood loss level are gained earlier than sAEs risk reduction.

Shorter operation time and improved surgical outcomes in laparoscopic donor right hepatectomy compared with open donor right hepatectomy.

BACKGROUND: Pure laparoscopic donor right hepatectomy is a complex procedure, and the safety and feasibility of this operation remain unclear. This study aimed to evaluate the clinical outcomes and learning curve of this operation performed by a single surgeon. METHODS: We retrospectively reviewed the initial 100 donors who underwent pure laparoscopic donor right hepatectomy or open donor right hepatectomy by a single surgeon from December 2012 to May 2019. Endpoints analyzed included intraoperative results, postoperative complications, and learning curve, which was evaluated using the cumulative sum method based on the operation time. We divided the pure laparoscopic donor right hepatectomy group into initial and recent groups based on the time point of overcoming the learning curve. RESULTS: The operative time was significantly shorter in the recent pure laparoscopic donor right hepatectomy group (n = 57; 181.0 ± 35.7 min) than in the open donor right hepatectomy (n = 50; 203.0 ± 37.3 min) and initial pure laparoscopic donor right hepatectomy (n = 43; 282.2 ± 59.2 min) groups (P < .001). Moreover, the length of hospital stay in the recent pure laparoscopic donor right hepatectomy group was significantly reduced compared to that in the open donor right hepatectomy group (7.7 ± 1.2 vs 5.8 ± 1.4; P < .001). The complication rate was reduced from 10% in the open donor right hepatectomy group and 8% in the initial pure laparoscopic donor right hepatectomy group to 2% in the recent pure laparoscopic donor right hepatectomy group. CONCLUSION: As technology advances, the surgical outcomes of pure laparoscopic donor right hepatectomy are comparable and the operation time of pure laparoscopic donor right hepatectomy is superior to those of open donor hepatectomy.

Perceptions of porta-celiac vascular models for hepatic surgery and their use in residency training.

BACKGROUND: Primary aspect of hepatic navigation surgery is the identification of source vascular details to preserve healthy liver which has a vascular anatomy quite challenging for the young surgeons. The purpose was to determine whether three-dimensional (3D) vascular pattern models of preoperative computed tomography (CT) images will assist resident-level trainees for hepatic surgery. METHODS: This study was based on the perception of residents who were presented with 5 different hepatic source vascular patterns and required to compare their perception level of CT, and 1:1 models in terms of importance of variability, differential of patterns and preoperative planning. RESULTS: All residents agree that models provided better understanding of vascular source and improved preplanning. Five stations provided qualitative assessment with results showing the usefulness of porta-celiac models when used as anatomical tools in preplanning (p = 0.04), simulation of interventional procedures (p = 0.02), surgical education (p = 0.01). None of the cases had scored less than 8.5. Responses related to understanding variations were significantly higher in the perception of the 3D model in all cases, furthermore 3D models were more useful for seniors in more complex cases 3 and 5. Some open-ended answers: "The 3D model can completely change the operation plan" One of the major factors for anatomical resection of liver transplantation is the positional relationship between the hepatic arteries and the portal veins. CONCLUSION: The plastic-like material presenting the hepatic vascularity enables the visualization of the origin, pattern, shape, and angle of the branches with appropriate spatial perception thus making it well-structured.

Learning curves in minimally invasive hepatectomy: systematic review and meta-regression analysis.

BACKGROUND: Minimally invasive hepatectomy (MIH) has become an important option for the treatment of various liver tumours. A major concern is the learning curve required. The aim of this study was to perform a systematic review and summarize current literature analysing the learning curve for MIH. METHODS: A systematic review of the literature pertaining to learning curves in MIH to July 2019 was performed using PubMed and Scopus databases. All original full-text articles published in English relating to learning curves for both laparoscopic liver resection (LLR), robotic liver resection (RLR), or a combination of these, were included. To explore quantitatively the learning curve for MIH, a meta-regression analysis was performed. RESULTS: Forty studies relating to learning curves in MIH were included. The median overall number of procedures required in studies utilizing cumulative summative (CUSUM) methodology for LLR was 50 (range 25-58) and for RLR was 25 (16-50). After adjustment for year of adoption of MIH, the CUSUM-derived caseload to surmount the learning curve for RLR was 47.1 (95 per cent c.i. 1.2 to 71.6) per cent; P = 0.046) less than that required for LLR. A year-on-year reduction in the number of procedures needed for MIH was observed, commencing at 48.3 cases in 1995 and decreasing to 23.8 cases in 2015. CONCLUSION: The overall learning curve for MIH decreased steadily over time, and appeared less steep for RLR compared with LLR.

Is resident assistance equivalent to fellows during hepatectomy?

OBJECTIVE: Hepatectomy is a complex operative procedure frequently performed at academic institutions with trainee participation. The aim of this study was to determine the effect of assistant's training level on outcomes following hepatectomy. METHODS: A retrospective review of a prospective, single-institution ACS-NSQIP database was performed for patients that underwent hepatectomy (2013-2016). Patients were divided by trainee assistant level: hepatopancreatobiliary (HPB) fellow versus general surgery resident (PGY 4-5). Demographic, perioperative, and 30-day outcome variables were compared using Chi-Square/Fisher's exact, Mann-Whitney U test, and multivariable regression. Cases involving a senior-level general surgery resident or HPB fellow as first assistant were included (n = 352). Those with a second attending, junior-level resident, or no documented assistant were excluded (n = 39). RESULTS: Patients undergoing hepatectomy with an HPB fellow as primary assistant had more frequent preoperative biliary stenting, longer operative time, and more concomitant procedures including biliary reconstruction, resulting in a higher rate of post-hepatectomy liver failure (PHLF) (15% vs. 8%, P = 0.044). However, trainee level did not impact PHLF on multivariable analysis (OR 0.60, 95% CI [0.29-1.25], P = 0.173). Fellows assisted with proportionally more major hepatectomies (45% vs. 31%; P = 0.010) and resections for hepatobiliary cancers (31% vs. 19%, P = 0.014). On stratified analysis of major and minor hepatectomies, outcomes were similar between trainee groups. CONCLUSION: Fellows performed higher complexity cases with longer operative time. Despite these differences, outcomes were similar regardless of assistant training level. Resident and HPB fellow participation in operations requiring liver resection provide comparable quality of care.

Major Laparoscopic Versus Open Resection for Hepatocellular Carcinoma: A Propensity Score-Matched Analysis Based on Surgeons' Learning Curve.

BACKGROUND: Surgical complications for surgeons still in the learning phase of major laparoscopic liver resection (LLR) have been frequently observed. We aimed to compare perioperative and long-term outcomes of laparoscopic and open surgery based on the surgeons' learning curve for LLR after propensity score-matched (PSM) analysis. METHODS: This was a retrospective study of all patients with a histologic diagnosis of hepatocellular carcinoma who underwent major hepatectomy between January 2013 and December 2018. A PSM analysis was used to compare the groups of patients who underwent LLR and open major liver resection (OLR) before and after the learning curve was maximized. RESULTS: Among 405 patients, 106 underwent LLR and 299 underwent OLR. The learning curve was maximized after 42 cases. Compared with OLR, LLR had more liver-related injury and grade III or higher complications during the learning phase. The LLR group had less blood loss, fewer transfusion requirements, and fewer liver-related complications during the 'experienced' phase. Hospital stay was significantly shorter during and after maximization of the learning curve in LLR compared with OLR. Operative time was comparable in the two phases. Overall, LLR was associated with less blood loss, fewer complications, and shorter hospital stay compared with open surgery. There was no significant difference in long-term survival outcomes between the two groups. CONCLUSIONS: LLR had a higher incidence of liver-related complications during the surgeon's learning phase compared with OLR. This association was significantly diminished with surgeon experience. Overall perioperative outcomes such as estimated blood loss, surgical complications, and hospital stay remained better for LLR compared with OLR.

The initiation, standardization and proficiency (ISP) phases of the learning curve for minimally invasive liver resection: comparison of a fellowship-trained surgeon with the pioneers and early adopters.

BACKGROUND: Using the Ideal Development Exploration Assessment and Long-term study (IDEAL) paradigm, Halls et al. created risk-adjusted cumulative sum (RA-CUSUM) curves concluding that Pioneers (P) and Early Adopters (EA) of minimally invasive (MI) liver resection obtained similar results after fewer cases. In this study, we applied this framework to a MI Hepatic-Pancreatic and Biliary fellowship-trained surgeon (FT) in order to assess where along the curves this generation fell. METHODS: The term FT was used to designate surgeons without previous independent operative experience who went from surgical residency directly into fellowship. Three phases of the learning curve were defined using published data on EAs and Ps of MI Hepatectomy, including phase 1 (initiation) (i.e., the first 17 or 50), phase 2 (standardization) (i.e., cases 18-46 or 1-50) and phase 3 (proficiency) (i.e., cases after 46, 50 or 135). Data analysis was performed using the Social Science Statistics software ( www.socscistatistics.com ). Statistical significance was defined as p < .05. RESULTS: From November 2007 until April 2018, 95 MI hepatectomies were performed by a FT. During phase 1, the FT approached larger tumors than the EA group (p = 0.002), that were more often malignant (94.1%) when compared to the P group (52.5%) (p < 0.001). During phase 2, the FT operated on larger tumors and more malignancies (93.1%) when compared to the Ps (p = 0.004 and p = 0.017, respectively). However, there was no difference when compared to the EA. In the phase 3, the EAs tended to perform more major hepatectomies (58.7) when compared to either the FT (30.6%) (p = 0.002) or the P's cases 51-135 and after 135 (35.3% and 44.3%, respectively) (both p values < 0.001). When compared to the Ps cases from 51-135, the FT operated on more malignancies (p = 0.012), but this was no longer the case after 135 cases by the Ps (p = 0.164). There were no statistically significant differences when conversions; major complications or 30- and 90-day mortality were compared among these 3 groups. DISCUSSION: Using the IDEAL framework and RA-CUSUM curves, a FT surgeon was found to have curves similar to EAs despite having no previous independent experience operating on the liver. As in our study, FTs may tend to approach larger and more malignant tumors and do more concomitant procedures in patients with higher ASA classifications than either of their predecessors, without statistically significant increases in major morbidity or mortality. CONCLUSION: It is possible that the ISP (i.e., initiation, standardization, proficiency) model could apply to other innovative surgical procedures, creating different learning curves depending on where along the IDEAL paradigm surgeons fall.

The ILLS Laparoscopic Liver Surgery Fellow Skills Curriculum.

INTRODUCTION: Laparoscopy is becoming the standard approach in liver surgery. As the degree of difficulty varies greatly from core skills to advanced procedures, strategies for teaching young surgeons need to be reconsidered. We here aimed to design a skills curriculum for LLR. METHODS: Using the nominal group technique, 22 substeps of LLR were identified by 61 hepatobiliary surgeons. The raters were asked to rate (1) the difficulty of substeps and (2) the minimum number of times that the substep must be performed for mastery of the technique. According to the frequency of defined substeps, being estimated on the basis of high volume center experiences (n = 222 LLR; 1/2017-12/2018), the center's training capacity and defined goals for a 2-year fellowship were calculated. RESULTS: Ten surgical substeps (45%) are routinely performed and can thus be taught sufficiently at centers carrying out ≥50 LLR in 2 years. As the mobilization of the right liver lobe and the dissection of the hepatic artery or portal vein is performed in only 27% and 28% of all LLR, respectively, sufficient training can only be provided at centers with ≥100 LLRs in 2 years. Mastery of complex parenchymal dissection (19%) and hilar lymphadenectomy (8%) can only be achieved in center performing ≥200 LLR in 2 years. CONCLUSION: We here suggest a stepwise approach for training of hepatobiliary fellows in LLR. Based on the estimated complexity of the substeps and the size of the center, not every substep can be learned within 2 years.

An innovative approach for laparoscopic liver resections. Training protocol.

AIM: To evaluate the benefits of systematical use of ex vivo liver model and CT imaging in the planning process for swine laparoscopic liver resections done by residents during a dedicated training program. MATERIAL AND METHODS: Thirty general surgery residents, part of a dedicated and continuous training program, were equally divided into two groups: first one which performed laparoscopic liver resections without planning stage and the second one which systematically used an interactive tutorial for establishing the strategy for the resection followed by performing open liver dissection and the same resection on an ex vivo swine model. Afterwards, laparoscopic procedures were performed on twenty anesthetized domestic pigs. RESULTS: All teams successfully completed the procedure, with no conversions to open approach and without trainers' intervention. The second group was faster than the first group on both minor and major resections (p=0.0001). The blood loss was significantly lower on the second group (p=0.005). DISCUSSION: The residents surpassed our expectations regarding the operation time, blood loss and conversions, validating our training program. The step-by-step program was developed using the IDEAL paradigm, being now at the end of the 2b phase (exploration), when the residents realize the benefits of this model. The reduction in blood loss and loss of functional parenchyma demonstrates the utility of a warming-up phase. CONCLUSIONS: The "warming up" by adding the imagistic and anatomical data to the core protocol offer more clarity before laparoscopic liver resections and makes an upgrade for our "step by step" protocol. KEY WORDS: Experimental model, Laparoscopic liver resections, Residents.

Impact of First Assistant Surgeon Experience on the Perioperative Outcomes of Laparoscopic Hepatectomies.

Introduction: This study aims to evaluate the impact of first assistant surgeon experience on the outcomes of laparoscopic hepatectomies in a university-affiliated teaching hospital. Methods: This is a retrospective study comparing outcomes of laparoscopic hepatectomies with first assistant surgeons of varying experience levels. Three hundred and eighty-five consecutive laparoscopic hepatectomies performed in a tertiary university-affiliated teaching hospital from 2012 to 2018 were included and stratified into three cohorts-Group 1 in which assistants were residents, Group 2 for fellows, and Group 3 for attendings. Baseline clinicopathologic variables and outcome measures were analyzed using the augmented inverse probability of treatment weighting approach, which is a propensity score-based method that combines aspects of covariate adjustment and inverse probability weighting. Results: Group 3 comprised a greater proportion of advanced- and expert-level surgeries based on the Iwate criteria; 33.8%, 32.2%, and 46.0% of patients underwent advanced- and expert-level surgeries in Groups 1, 2, and 3, respectively. Group 3 had consistently higher operative times as well as more frequent use and longer duration of Pringle's maneuver (P < .05). The median operative times for Groups 1, 2, and 3 were 195, 195, and 290 minutes, respectively. Pringle's maneuver was applied in 26.9%, 33.9%, and 60.2% of patients with a corresponding median duration of 35, 36, and 45 minutes, respectively. None of the other perioperative and postoperative outcomes demonstrated statistically significant differences. Conclusion: With an appropriate selection of cases, participation of residents as first assistants in laparoscopic hepatectomies can be encouraged without compromise in perioperative outcomes.

Critical appraisal of the learning curve of minimally invasive hepatectomy: experience with the first 200 cases of a Southeast Asian early adopter.

BACKGROUND: A recent study analysing the experience of fellowship-trained early adopting surgeons during stage 3 of the IDEAL paradigm demonstrated that the learning curve (LC) of minimally invasive hepatectomy (MIH) can be shortened compared to the long steep LC of pioneering surgeons. In this study, we aimed to critically appraise the contemporary learning experience with MIH of a 'self-taught' early adopter during stage 3 of the IDEAL paradigm. METHODS: A review of the first 200 patients who underwent MIH over an 88-month period since 2011 by a single surgeon who had no prior training in MIH was conducted. The cohort was divided into four groups of 50 patients. Risk-adjusted cumulative sum analysis of the LC was performed. RESULTS: Two hundred patients underwent MIH and there were 13 (6.5%) open conversions. There were 55 (27.5%) major resections and 94 (47.0%) were graded as high/expert difficulty according to the Iwate criteria. Fifty-one (25.5%) patients had cirrhosis and 98 (49%) had previous abdominal surgery including 28 (14%) with previous liver resections. There were five (2.5%) major (Grade 3b-5) morbidities, zero 30-day mortality and one (0.5%) 90-day mortality. Comparison across the four groups demonstrated a significant trend towards increased adoption of total MIH, increased multifocal tumours, increased performance of major hepatectomies and decreased blood loss. Risk-adjusted cumulative sum analysis demonstrated that the LC in terms of blood loss, blood transfusion rate, open conversion rate, operation time and post-operative length of stay to be 65 cases. The LC for MIH of Iwate low/intermediate difficulty and of Iwate high/expert difficulty were 35 and 30 cases, respectively. CONCLUSION: MIH of all difficulty levels is feasible and can be safely adopted today even by surgeons with no prior formal training. The LC of the 'self-taught' early adopter is about 65 cases.

Learning Curve Under Proctorship of Pure Laparoscopic Living Donor Left Lateral Sectionectomy for Pediatric Transplantation.

OBJECTIVE: To evaluate the learning curve of an expert liver transplantation surgeon approaching fully laparoscopic living donor left lateral sectionectomy (L-LLS) under proctorship. BACKGROUND: Laparoscopic liver resections necessitate a long learning curve trough a stepwise fulfillment of difficulties. L-LLS requires expertise in both living donor liver transplantation and advanced laparoscopic liver surgery. There is currently no data about the learning curve of L-LLS. METHODS: A total of 72 pure L-LLS were included in this study. A Broken line model was used to identify the periods of the learning curve. A CUSUM analysis of the operative time was performed to evaluate improvements of outcomes with time. To evaluate the relationship between operative time and progressive number of procedures, a linear regression model was applied. A receiver operating characteristic (ROC) curve was carried out to identify the cutoff for completion of the learning curve. RESULTS: Operative time decreased with the progressive increase of procedures. Two cutoffs and 3 different periods were identified: cases 1 to 22, cases 23 to 55, and cases 56 to 72. A significant decrease in blood loss and operative time was noted. The CUSUM analysis showed an increase in operative time in the first period, a stable duration in the second period, and a decrease in the last. Blood loss was significantly associated with an increase in operative time (P = 0.003). According to the ROC curve, the learning curve was completed after 25 procedures. CONCLUSIONS: L-LLS is a safe procedure that can be standardized and successfully taught to surgeons with large experience in donor hepatectomy through a proctored learning curve.

Learning curve of laparoscopic living donor right hepatectomy.

BACKGROUND: The feasibility and learning curve of laparoscopic living donor right hepatectomy was assessed. METHODS: Donors who underwent right hepatectomy performed by a single surgeon were reviewed. Comparisons between open and laparoscopy regarding operative outcomes, including number of bile duct openings in the graft, were performed using propensity score matching. RESULTS: From 2014 to 2018, 103 and 96 donors underwent laparoscopic and open living donor right hepatectomy respectively, of whom 64 donors from each group were matched. Mean(s.d.) duration of operation (252·2(41·9) versus 304·4(66·5) min; P < 0·001) and median duration of hospital stay (8 versus 10 days; P = 0·002) were shorter in the laparoscopy group. There was no difference in complication rates of donors (P = 0·298) or recipients (P = 0·394) between the two groups. Total time for laparoscopy decreased linearly (R2 = 0·407, ß = -0·914, P = 0·001), with the decrease starting after approximately 50 procedures when cases were divided into four quartiles (2nd versus 3rd quartile, P = 0·001; 3rd versus 4th quartile, P = 0·023). Although grafts with bile duct openings were more abundant in the laparoscopy group (P = 0·022), no difference was found in the last two quartiles (P = 0·207). CONCLUSION: Laparoscopic living donor right hepatectomy is feasible and an experience of approximately 50 cases may surpass the learning curve.

ANTECEDENTES: Se evaluó la viabilidad y la curva de aprendizaje de la hepatectomía derecha de donante vivo MÉTODOS: Se llevó a cabo una revisión de los donantes sometidos a hepatectomía derecha por un único cirujano. Las comparaciones entre el abordaje abierto y laparoscópico con respecto a los resultados operatorios, incluyendo el número of aberturas de los conductos biliares en el injerto se realizó utilizando un análisis de emparejamiento por puntaje de propensión. RESULTADOS: Desde 2014 a 2018, 96 y 103 donantes fueron sometidos a hepatectomía derecho de donante vivo por cirugía abierta y laparoscópica, respectivamente, de los cuales 64 donantes fueron emparejados para ambos grupos. La media del tiempo operatorio (304,3 ± 66,5 versus 252,2 ± 41,9 minutos, P < 0,001) y la mediana de la estancia hospitalaria fueron más cortas en el grupo de cirugía laparoscópica (10 versus 8 días, P = 0,002). No hubo diferencias entre ambos grupos en las tasas de complicaciones de los donantes (P = 0,298) o receptores (P = 0,394). El tiempo total de la laparoscopia disminuyó linealmente (R2= 0,407, ß = -0,914, P = 0,001) y esta disminución comenzó a partir aproximadamente de los 50 casos realizados cuando los casos fueron divididos en cuatro cuartiles (segundo a tercero y tercero a cuarto, P = 0,001 y P = 0,023, respectivamente). Aunque los injertos con aperturas de los conductos biliares fueron más numerosos en el grupo laparoscópico (P = 0,022), no se hallaron diferencias en los dos últimos cuartiles (P = 0,207). CONCLUSIÓN: La hepatectomía derecha de donante vivo por vía laparoscópica es viable, y una experiencia de aproximadamente 50 casos, puede superar la curva de aprendizaje.

Modified liver hanging maneuver in laparoscopic major hepatectomy: the learning curve and evolution of indications.

BACKGROUND: Laparoscopic major hepatectomy is a technically challenging procedure requiring a steep learning curve. The liver hanging maneuver is a useful technique in liver resection, especially for large or invasive tumors, a relative contraindication of the laparoscopic approach. Therefore, this study aimed to evaluate the learning curve for laparoscopic major hepatectomy using the liver hanging maneuver and extended indications. METHODS: Patients who underwent laparoscopic major hepatectomy using the liver hanging maneuver by a single surgeon from January 2013 and September 2018 were retrospectively reviewed. Our hanging technique involves placing the hanging tape along the inferior vena cava for right-sided hepatectomy or the ligamentum venosum for left-sided hepatectomy. The upper end of the tape was placed at the lateral side of the major hepatic veins. The learning curve for operating time and blood loss was evaluated using the cumulative sum (CUSUM) method. RESULTS: Among 53 patients, 18 underwent right hepatectomy, 26 underwent left hepatectomy, and 9 underwent right posterior sectionectomy. CUSUM analysis showed that operative time and blood loss improved after the 30th laparoscopic major hepatectomy. The 53 consecutive patients were divided into two groups (early, patients 1-30; late, patients 31-53). The median operative time was lower in the late group, but the difference was not statistically significant (270 vs. 245 min, p = 0.261). The median blood loss was also significantly lower in the late group (350 vs. 150 ml, p < 0.001). Large tumors (measuring > 10 cm) and tumors in proximity to major vessels were significantly higher in the late group (0 vs. 17.4%, p = 0.018; 3.3 vs. 21.7%, p = 0.036; respectively). CONCLUSION: This study shows that laparoscopic major hepatectomy using the modified liver hanging maneuver has a learning curve of 30 cases. After procedure standardization, the indications have gradually been extended to large or invasive tumors.

A clinical pilot study of Resection Process Map: A novel virtual hepatectomy software to visualize the resection process, case series.

BACKGROUND: Preoperative simulation of liver resection to visualize the intraoperative cutting process, including liver deformation, may help surgeons to more accurately implement hepatectomy. We developed a novel simulation software called Resection Process Map (RPM). The present study was performed to evaluate the feasibility and efficacy of RPM as a tool for preoperative simulation and surgical education for liver surgery. MATERIALS AND METHODS: Twenty-four patients who underwent anatomical hepatic resection at our institute from February 2017 to May 2018 were enrolled in this study. The time needed to prepare RPM for each patient was recorded. The imaging similarity between the image provided by RPM and the intraoperative photograph was evaluated with the Dice similarity coefficient and locational displacement of the vessels of interest. The surgeons completed questionnaires. The educational effect was assessed by a survey administered to medical students who attended clinical clerkship at our department from October 2017 to December 2018. RESULTS: The time required to prepare the dataset for RPM was 199 ±â€¯20 s after completion of operative planning in SYNAPSE VINCENT. The Dice similarity coefficient for surface similarity was 0.85 ±â€¯0.06, where 1.00 indicates perfect concordance. The mean positional displacement of the vessels of interest was 8.7 ±â€¯6.7 mm. Medical students' application of RPM significantly improved their survey score (use vs. non-use of RPM, 6.5 vs, 4.6, respectively; p < 0.001). CONCLUSION: RPM allows for preoperative simulation of hepatectomy and might be helpful for many surgeons. RPM is also useful for education of medical students.