Short-term Outcomes of Robotic Versus Open Pancreatoduodenectomy: Propensity Score-matched Analysis.

OBJECTIVE: The goal of the current study was to investigate the perioperative outcomes of robotic pancreaticoduodenectomy (RPD) and open pancreaticoduodenectomy (OPD) in a high-volume center. BACKGROUND: Despite RPDs prospective advantages over OPD, current evidence comparing the 2 has been limited and has prompted further investigation. The aim of this study was to compare both approaches while including the learning curve phase for RPD. METHODS: A 1:1 propensity score-matched analysis of a prospective database of RPD with OPD (2017-2022) at a high-volume center was performed. The main outcomes were overall- and pancreas-specific complications. RESULTS: Of 375 patients who underwent PD (OPD n=276; RPD n=99), 180 were included in propensity score-matched analysis (90 per group). RPD was associated with less blood loss [500 (300-800) vs 750 (400-1000) mL; P =0.006] and more patients without a complication (50% vs 19%; P <0.001). Operative time was longer [453 (408-529) vs 306 (247-362) min; P <0.001]; in patients with ductal adenocarcinoma, fewer lymph nodes were harvested [24 (18-27) vs 33 (27-39); P <0.001] with RPD versus OPD. There were no significant differences for major complications (38% vs 47%; P =0.291), reoperation rate (14% vs 10%; P =0.495), postoperative pancreatic fistula (21% vs 23%; P =0.858), and patients with the textbook outcome (62% vs 55%; P =0.452). CONCLUSIONS: Including the learning phase, RPD can be safely implemented in high-volume settings and shows potential for improved perioperative outcomes versus OPD. Pancreas-specific morbidity was unaffected by the robotic approach. Randomized trials with specifically trained pancreatic surgeons and expanded indications for the robotic approach are needed.

The PAncreatic Surgery Composite Endpoint PACE - Development and Validation of a Clinically Relevant Endpoint Requiring Lower Sample Sizes.

OBJECTIVE: To provide a composite endpoint in pancreatic surgery. SUMMARY BACKGROUND DATA: Single endpoints in prospective and randomized studies have become impractical due to their low frequency and the marginal benefit of new interventions. METHODS: Data from prospective studies were used to develop (n=1273) and validate (n=544) a composite endpoint based on postoperative pancreatic fistula, post-pancreatectomy hemorrhage as well as reoperation and reinterventions. All patients had pancreatectomies of different extents. The association of the developed PAncreatic surgery Composite Endpoint (PACE) with prolonged length of hospital stay (LOS) >75th percentile and mortality was assessed. A single-institution database was used for external validation (n = 2666). Sample size calculations were made for single outcomes and the composite endpoint. RESULTS: In the internal validation cohort, the PACE demonstrated an AUC of 78.0%, a sensitivity of 90.4% and a specificity of 67.6% in predicting a prolonged LOS. In the external cohort, the AUC was 76.9%, the sensitivity 73.8% and the specificity 80.1%. The 90-day mortality rate was significantly different for patients with a positive versus a negative PACE both in the development and internal validation cohort (5.1% vs 0.9%; P< 0.001), as well as in the external validation cohort (8.5% vs 1.2%, P< 0.001). The PACE enabled sample size reductions of up to 80.5% compared to single outcomes. CONCLUSION: The PACE performed well in predicting prolonged hospital stays and can be used as a standardized and clinically relevant endpoint for future prospective trials enabling lower sample sizes and therefore improved feasibility compared to single outcome parameters.

Towards a Standardization of Learning Curve Assessment in Minimally Invasive Liver Surgery.

OBJECTIVE: The aim was to analyze the learning curves of minimal invasive liver surgery(MILS) and propose a standardized reporting. SUMMARY BACKGROUND DATA: MILS offers benefits compared to open resections. For a safe introduction along the learning curve, formal training is recommended. However, definitions of learning curves and methods to assess it lack standardization. METHODS: A systematic review of PubMed, Web of Science, and CENTRAL databases identified studies on learning curves in MILS. The primary outcome was the number needed to overcome the learning curve. Secondary outcomes included endpoints defining learning curves, and characterization of different learning phases(competency, proficiency and mastery). RESULTS: 60 articles with 12'241 patients and 102 learning curve analyses were included. The laparoscopic and robotic approach was evaluated in 71 and 18 analyses and both approaches combined in 13 analyses. Sixty-one analyses (60%) based the learning curve on statistical calculations. The most often used parameters to define learning curves were operative time (n=64), blood loss (n=54), conversion (n=42) and postoperative complications (n=38). Overall competency, proficiency and mastery were reached after 34 (IQR 19-56), 50 (IQR 24-74), 58 (IQR 24-100) procedures respectively. Intraoperative parameters improved earlier (operative time: competency to proficiency to mastery: -13%, 2%; blood loss: competency to proficiency to mastery: -33%, 0%; conversion rate (competency to proficiency to mastery; -21%, -29%), whereas postoperative complications improved later (competency to proficiency to mastery: -25%, -41%). CONCLUSIONS: This review summarizes the highest evidence on learning curves in MILS taking into account different definitions and confounding factors. A standardized three-phase reporting of learning phases (competency, proficiency, mastery) is proposed and should be followed.

Reconstruction Techniques and Associated Morbidity in Minimally Invasive Gastrectomy for Cancer - Insights from the GastroBenchmark and GASTRODATA databases.

OBJECTIVE/BACKGROUND: Various anastomotic and reconstruction techniques are used for minimally invasive total (miTG) and distal gastrectomy (miDG). Their effects on postoperative morbidity have not been extensively studied. METHODS: MiTG and miDG patients were selected from 9356 oncological gastrectomies performed 2017-2021 in 44 centers. Endpoints included anastomotic leakage (AL) rate and postoperative morbidity tested by multivariable analysis. RESULTS: Three major anastomotic techniques (circular stapled (CS); linear stapled (LS); hand sewn (HS)), and three major bowel reconstruction types (Roux (RX); Billroth I (BI); Billroth II (BII)) were identified in miTG (n=878) and miDG (n=3334). Postoperative complications including AL (5.2% vs. 1.1%), overall (28.7% vs. 16.3%) and major morbidity (15.7% vs. 8.2%), as well as 90-day mortality (1.6% vs. 0.5%) were higher after miTG compared with miDG. After miTG, AL rate was higher after CS (4.3%) and HS (7.9%) compared with LS (3.4%). Similarly, major complications (LS: 9.7%, CS: 16.2%, HS: 12.7%) were lowest after LS. Multivariate analysis confirmed anastomotic technique as predictive factor for AL, overall and major complications. In miDG, AL rate (BI: 1.4%, BII 0.8%, RX 1.2%), overall (BI: 14.5%, BII: 15.0%, RX: 18.7%,) and major morbidity (BI: 7.9%, BII: 9.1%, RX: 7.2%), and mortality (BI: 0%, BII: 0.1%, RY: 1.1%%) were not affected by bowel reconstruction. CONCLUSION: In oncologically suitable situations, miDG should be preferred to miTG, as postoperative morbidity is significantly lower. LS should be a preferred anastomotic technique for miTG in Western Centers. Conversely, bowel reconstruction in DG may be chosen according to surgeon's preference.

Effects of endoluminal vacuum sponge therapy on the perfusion of gastric conduit in a porcine model for esophagectomy.

BACKGROUND: After esophagectomy, the postoperative rate of anastomotic leakage is up to 30% and is the main driver of postoperative morbidity. Contemporary management includes endoluminal vacuum sponge therapy (EndoVAC) with good success rates. Vacuum therapy improves tissue perfusion in superficial wounds, but this has not been shown for gastric conduits. This study aimed to assess gastric conduit perfusion with EndoVAC in a porcine model for esophagectomy. MATERIAL AND METHODS: A porcine model (n = 18) was used with gastric conduit formation and induction of ischemia at the cranial end of the gastric conduit with measurement of tissue perfusion over time. In three experimental groups EndoVAC therapy was then used in the gastric conduit (- 40, - 125, and - 200 mmHg). Changes in tissue perfusion and tissue edema were assessed using hyperspectral imaging. The study was approved by local authorities (Project License G-333/19, G-67/22). RESULTS: Induction of ischemia led to significant reduction of tissue oxygenation from 65.1 ± 2.5% to 44.7 ± 5.5% (p < 0.01). After EndoVAC therapy with - 125 mmHg a significant increase in tissue oxygenation to 61.9 ± 5.5% was seen after 60 min and stayed stable after 120 min (62.9 ± 9.4%, p < 0.01 vs tissue ischemia). A similar improvement was seen with EndoVAC therapy at - 200 mmHg. A nonsignificant increase in oxygenation levels was also seen after therapy with - 40 mmHg, from 46.3 ± 3.4% to 52.5 ± 4.3% and 53.9 ± 8.1% after 60 and 120 min respectively (p > 0.05). An increase in tissue edema was observed after 60 and 120 min of EndoVAC therapy with - 200 mmHg but not with - 40 and - 125 mmHg. CONCLUSIONS: EndoVAC therapy with a pressure of - 125 mmHg significantly increased tissue perfusion of ischemic gastric conduit. With better understanding of underlying physiology the optimal use of EndoVAC therapy can be determined including a possible preemptive use for gastric conduits with impaired arterial perfusion or venous congestion.

Structured feedback and operative video debriefing with critical view of safety annotation in training of laparoscopic cholecystectomy: a randomized controlled study.

BACKGROUND: The learning curve in minimally invasive surgery (MIS) is lengthened compared to open surgery. It has been reported that structured feedback and training in teams of two trainees improves MIS training and MIS performance. Annotation of surgical images and videos may prove beneficial for surgical training. This study investigated whether structured feedback and video debriefing, including annotation of critical view of safety (CVS), have beneficial learning effects in a predefined, multi-modal MIS training curriculum in teams of two trainees. METHODS: This randomized-controlled single-center study included medical students without MIS experience (n = 80). The participants first completed a standardized and structured multi-modal MIS training curriculum. They were then randomly divided into two groups (n = 40 each), and four laparoscopic cholecystectomies (LCs) were performed on ex-vivo porcine livers each. Students in the intervention group received structured feedback after each LC, consisting of LC performance evaluations through tutor-trainee joint video debriefing and CVS video annotation. Performance was evaluated using global and LC-specific Objective Structured Assessments of Technical Skills (OSATS) and Global Operative Assessment of Laparoscopic Skills (GOALS) scores. RESULTS: The participants in the intervention group had higher global and LC-specific OSATS as well as global and LC-specific GOALS scores than the participants in the control group (25.5 ± 7.3 vs. 23.4 ± 5.1, p = 0.003; 47.6 ± 12.9 vs. 36 ± 12.8, p < 0.001; 17.5 ± 4.4 vs. 16 ± 3.8, p < 0.001; 6.6 ± 2.3 vs. 5.9 ± 2.1, p = 0.005). The intervention group achieved CVS more often than the control group (1. LC: 20 vs. 10 participants, p = 0.037, 2. LC: 24 vs. 8, p = 0.001, 3. LC: 31 vs. 8, p < 0.001, 4. LC: 31 vs. 10, p < 0.001). CONCLUSIONS: Structured feedback and video debriefing with CVS annotation improves CVS achievement and ex-vivo porcine LC training performance based on OSATS and GOALS scores.

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.

Intraoperative liver deformation and organ motion caused by ventilation, laparotomy, and pneumoperitoneum in a porcine model for image-guided liver surgery.

BACKGROUND: Image-guidance promises to make complex situations in liver interventions safer. Clinical success is limited by intraoperative organ motion due to ventilation and surgical manipulation. The aim was to assess influence of different ventilatory and operative states on liver motion in an experimental model. METHODS: Liver motion due to ventilation (expiration, middle, and full inspiration) and operative state (native, laparotomy, and pneumoperitoneum) was assessed in a live porcine model (n = 10). Computed tomography (CT)-scans were taken for each pig for each possible combination of factors. Liver motion was measured by the vectors between predefined landmarks along the hepatic vein tree between CT scans after image segmentation. RESULTS: Liver position changed significantly with ventilation. Peripheral regions of the liver showed significantly higher motion (maximal Euclidean motion 17.9 ± 2.7 mm) than central regions (maximal Euclidean motion 12.6 ± 2.1 mm, p < 0.001) across all operative states. The total average motion measured 11.6 ± 0.7 mm (p < 0.001). Between the operative states, the position of the liver changed the most from native state to pneumoperitoneum (14.6 ± 0.9 mm, p < 0.001). From native state to laparotomy comparatively, the displacement averaged 9.8 ± 1.2 mm (p < 0.001). With pneumoperitoneum, the breath-dependent liver motion was significantly reduced when compared to other modalities. Liver motion due to ventilation was 7.7 ± 0.6 mm during pneumoperitoneum, 13.9 ± 1.1 mm with laparotomy, and 13.5 ± 1.4 mm in the native state (p < 0.001 in all cases). CONCLUSIONS: Ventilation and application of pneumoperitoneum caused significant changes in liver position. Liver motion was reduced but clearly measurable during pneumoperitoneum. Intraoperative guidance/navigation systems should therefore account for ventilation and intraoperative changes of liver position and peripheral deformation.

Robotic hepaticojejunostomy training in novices using robotic simulation and dry-lab suturing (ROSIM): randomized controlled crossover trial.

BACKGROUND: Robotic suturing training is in increasing demand and can be done using suture-pads or robotic simulation training. Robotic simulation is less cumbersome, whereas a robotic suture-pad approach could be more effective but is more costly. A training curriculum with crossover between both approaches may be a practical solution. However, studies assessing the impact of starting with robotic simulation or suture-pads in robotic suturing training are lacking. METHODS: This was a randomized controlled crossover trial conducted with 20 robotic novices from 3 countries who underwent robotic suturing training using an Intuitive Surgical® X and Xi system with the SimNow (robotic simulation) and suture-pads (dry-lab). Participants were randomized to start with robotic simulation (intervention group, n = 10) or suture-pads (control group, n = 10). After the first and second training, all participants completed a robotic hepaticojejunostomy (HJ) in biotissue. Primary endpoint was the objective structured assessment of technical skill (OSATS) score during HJ, scored by two blinded raters. Secondary endpoints were force measurements and a qualitative analysis. After training, participants were surveyed regarding their preferences. RESULTS: Overall, 20 robotic novices completed both training sessions and performed 40 robotic HJs. After both trainings, OSATS was scored higher in the robotic simulation-first group (3.3 ± 0.9 vs 2.5 ± 0.8; p = 0.049), whereas the median maximum force (N) (5.0 [3.2-8.0] vs 3.8 [2.3-12.8]; p = 0.739) did not differ significantly between the groups. In the survey, 17/20 (85%) participants recommended to include robotic simulation training, 14/20 (70%) participants preferred to start with robotic simulation, and 20/20 (100%) to include suture-pad training. CONCLUSION: Surgical performance during robotic HJ in robotic novices was significantly better after robotic simulation-first training followed by suture-pad training. A robotic suturing curriculum including both robotic simulation and dry-lab suturing should ideally start with robotic simulation.

An international Delphi consensus for surgical quality assessment of lymphadenectomy and anastomosis in minimally invasive total gastrectomy for gastric cancer.

BACKGROUND: Minimally invasive total gastrectomy (MITG) is a mainstay for curative treatment of patients with gastric cancer. To define and standardize optimal surgical techniques and further improve clinical outcomes through the enhanced MITG surgical quality, there must be consensus on the key technical steps of lymphadenectomy and anastomosis creation, which is currently lacking. This study aimed to determine an expert consensus from an international panel regarding the technical aspects of the performance of MITG for oncological indications using the Delphi method. METHODS: A 100-point scoping survey was created based on the deconstruction of MITG into its key technical steps through local and international expert opinion and literature evidence. An international expert panel comprising upper gastrointestinal and general surgeons participated in multiple rounds of a Delphi consensus. The panelists voted on the issues concerning importance, difficulty, or agreement using an online questionnaire. A priori consensus standard was set at > 80% for agreement to a statement. Internal consistency and reliability were evaluated using Cronbach's α. RESULTS: Thirty expert upper gastrointestinal and general surgeons participated in three online Delphi rounds, generating a final consensus of 41 statements regarding MITG for gastric cancer. The consensus was gained from 22, 12, and 7 questions from Delphi rounds 1, 2, and 3, which were rephrased into the 41 statetments respectively. For lymphadenectomy and aspects of anastomosis creation, Cronbach's α for round 1 was 0.896 and 0.886, and for round 2 was 0.848 and 0.779, regarding difficulty or importance. CONCLUSIONS: The Delphi consensus defined 41 steps as crucial for performing a high-quality MITG for oncological indications based on the standards of an international panel. The results of this consensus provide a platform for creating and validating surgical quality assessment tools designed to improve clinical outcomes and standardize surgical quality in MITG.

Laparoscopic but not open surgical skills can be transferred to robot-assisted surgery: A systematic review and meta-analysis.

BACKGROUND: With an increase in robot-assisted surgery across all specialties, adequate training and credentialing strategies need to be identified to ensure patients safety. The meta-analysis assesses the transferability of technical surgical skills between laparoscopic surgery, open surgery, and robot-assisted surgery. DESIGN: A systematic search was conducted in Medline, Cochrane Central Register of Controlled Trials, and Web of Science. Outcomes were categorized into time, process, product, and composite outcome measures and pooled separately using Hedges'g (standardized mean difference [SMD]). Subgroup analyses were performed to assess the effect of study design, virtual reality platforms and task difficulty. RESULTS: Out of 14,120 screened studies, 30 were included in the qualitative synthesis and 26 in the quantitative synthesis. Technical surgical skill transfer was demonstrated from laparoscopic to robot-assisted surgery (composite: SMD 0.40, 95%-confidence interval [CI] [0.19; 0.62], time: SMD 0.62, CI [0.33; 0.91]) and vice versa (composite: SMD 0.66, CI [0.33; 0.99], time [basic skills]: SMD 0.36, CI [0.01; 0.72]). No skill transfer was seen from open to robot-assisted surgery with limited available data. CONCLUSION: Technical surgical skills can be transferred from laparoscopic to robot-assisted surgery and vice versa. Robot-assisted and laparoscopic surgical skills training and credentialing should not be regarded separately, but a reasonable combination could shorten overall training times and increase efficiency. Previous experience in open surgery should not be considered as an imperative prerequisite for training in robot-assisted surgery. Recommendations for studies assessing skill transfer are proposed to increase comparability and significance of future studies. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42018104507.

Proficiency in bariatric surgery may shorten the learning curve for minimally-invasive D2 gastrectomy.

INTRODUCTION: Evidence from Asian studies suggests that minimally-invasive gastrectomy achieves equivalent oncological but improved perioperative outcomes compared to open surgery. Oncological gastric resections are less frequent in European countries. Index procedures may play a role for the learning curve of minimally-invasive gastrectomy. The aim of our study was to evaluate if skills acquired in bariatric surgery allow a safe and oncologically adequate implementation of minimally-invasive gastrectomy in a cohort of european patients. METHODS: In this single-center retrospective study, all patients who received primary bariatric surgery between January 2015 and December 2018 and minimally-invasive surgery for gastric cancer treated from June 2019 to January 2023 were evaluated. Primary endpoints were operation time, lymph node yield and lymph node fractions. Secondary endpoints included postoperative complications and oncological outcomes. RESULTS: Learning curves for two surgeons with 350 bariatric procedures and 44 minimally-invasive gastrectomies were analyzed. For bariatric surgery, the mean operation time decreased from initially 82 ± 27 to 45 ± 21 min and 118 ± 28 to 81 ± 36 min for sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB), while the complication rate remained within the international benchmark. For laparoscopic gastrectomy (n = 30), operation times decreased but then remained stable over time. Operation times for the robotic platform were longer (302 ± 60 vs. 390 ± 48 min; p < 0.001) with the learning curve remaining incomplete after 14 procedures. R0 status was achieved in 95.5% of patients; the mean number of lymph nodes retrieved was 37 ± 14 with no differences between the groups. Complete mesogastric excision was more frequently achieved during the later laparoscopic cases whereas it occurred earlier for the robotic group (p = 0.004). Perioperative morbidity was comparable to the European benchmark. Textbook outcome was achieved in 54.4% of the cases. CONCLUSION: In summary, we could demonstrate a successful skill transfer from bariatric surgery to minimally-invasive laparoscopic oncological gastric surgery enabling safe and oncologically adequate minimally-invasive D2 gastrectomy in a central European patient collective.

Robotic Distal Pancreatectomy: A Novel Standard of Care? Benchmark Values for Surgical Outcomes From 16 International Expert Centers.

BACKGROUND AND OBJECTIVE: Robotic distal pancreatectomy (DP) is an emerging attractive approach, but its role compared with laparoscopic or open surgery remains unclear. Benchmark values are novel and objective tools for such comparisons. The aim of this study was to identify benchmark cutoffs for many outcome parameters for DP with or without splenectomy beyond the learning curve. METHODS: This study analyzed outcomes from international expert centers from patients undergoing robotic DP for malignant or benign lesions. After excluding the first 10 cases in each center to reduce the effect of the learning curve, consecutive patients were included from the start of robotic DP up to June 2020. Benchmark patients had no significant comorbidities. Benchmark cutoff values were derived from the 75th or the 25th percentile of the median values of all benchmark centers. Benchmark values were compared with a laparoscopic control group from 4 high-volume centers and published open DP landmark series. RESULTS: Sixteen centers contributed 755 cases, whereof 345 benchmark patients (46%) were included the analysis. Benchmark cutoffs included: operation time ≤300 minutes, conversion rate ≤3%, clinically relevant postoperative pancreatic fistula ≤32%, 3 months major complication rate ≤26.7%, and lymph node retrieval ≥9. The comprehensive complication index at 3 months was ≤8.7 without deterioration thereafter. Compared with robotic DP, laparoscopy had significantly higher conversion rates (5×) and overall complications, while open DP was associated with more blood loss and longer hospital stay. CONCLUSION: This first benchmark study demonstrates that robotic DP provides superior postoperative outcomes compared with laparoscopic and open DP. Robotic DP may be expected to become the approach of choice in minimally invasive DP.

Video-based training of situation awareness enhances minimally invasive surgical performance: a randomized controlled trial.

BACKGROUND: Many training curricula were introduced to deal with the challenges that minimally invasive surgery (MIS) presents to the surgeon. Situational awareness (SA) is the ability to process information effectively. It depends on general cognitive abilities and can be divided into three steps: perceiving cues, linking cues to knowledge and understanding their relevance, and predicting possible outcomes. Good SA is crucial to predict and avoid complications and respond efficiently. This study aimed to introduce the concept of SA into laparoscopic training. METHODS: This is a prospective, randomized, controlled study conducted at the MIS Training Center of Heidelberg University Hospital. Video sessions showing the steps of the laparoscopic cholecystectomy (LC) were used for cognitive training. The intervention group trained SA with interposed questions inserted into the video clips. The identical video clips, without questions, were presented to the control group. Performance was assessed with validated scores such as the Objective Structured Assessment of Technical Skills (OSATS) during LC. RESULTS: 72 participants were enrolled of which 61 were included in the statistical analysis. The SA-group performed LC significantly better (OSATS-Score SA: 67.0 ± 11.5 versus control: 59.1 ± 14.0, p value = 0.034) and with less errors (error score SA: 3.5 ± 1.9 versus control: 4.7 ± 2.0, p value = 0.027). No difference in the time taken to complete the procedure was found. The benefit assessment analysis showed no difference between the groups in terms of perceived learning effect, concentration, or expediency. However, most of the control group indicated retrospectively that they believed they would have benefitted from the intervention. CONCLUSION: This study suggests that video-based SA training for laparoscopic novices has a positive impact on performance and error rate. SA training should thus be included as one aspect besides simulation and real cases in a multimodal curriculum to improve the efficiency of laparoscopic surgical skills training.

Telestration with augmented reality improves the performance of the first ten ex vivo porcine laparoscopic cholecystectomies: a randomized controlled study.

INTRODUCTION: The learning curve in minimally invasive surgery (MIS) is steep compared to open surgery. One of the reasons is that training in the operating room in MIS is mainly limited to verbal instructions. The iSurgeon telestration device with augmented reality (AR) enables visual instructions, guidance, and feedback during MIS. This study aims to compare the effects of the iSurgeon on the training of novices performing repeated laparoscopic cholecystectomy (LC) on a porcine liver compared to traditional verbal instruction methods. METHODS: Forty medical students were randomized into the iSurgeon and the control group. The iSurgeon group performed 10 LCs receiving interactive visual guidance. The control group performed 10 LCs receiving conventional verbal guidance. The performance assessment using Objective Structured Assessments of Technical Skills (OSATS) and Global Operative Assessment of Laparoscopic Skills (GOALS) scores, the total operating time, and complications were compared between the two groups. RESULTS: The iSurgeon group performed LCs significantly better (global GOALS 17.3 ± 2.6 vs. 16 ± 2.6, p ≤ 0.001, LC specific GOALS 7 ± 2 vs. 5.9 ± 2.1, p ≤ 0.001, global OSATS 25.3 ± 4.3 vs. 23.5 ± 3.9, p ≤ 0.001, LC specific OSATS scores 50.8 ± 11.1 vs. 41.2 ± 9.4, p ≤ 0.001) compared to the control group. The iSurgeon group had significantly fewer intraoperative complications in total (2.7 ± 2.0 vs. 3.6 ± 2.0, p ≤ 0.001) than the control group. There was no difference in operating time (79.6 ± 25.7 vs. 84.5 ± 33.2 min, p = 0.087). CONCLUSION: Visual guidance using the telestration device with AR, iSurgeon, improves performance and lowers the complication rates in LCs in novices compared to conventional verbal expert guidance.

Telestration with augmented reality improves surgical performance through gaze guidance.

BACKGROUND: In minimally invasive surgery (MIS), trainees need to learn how to interpret the operative field displayed on the laparoscopic screen. Experts currently guide trainees mainly verbally during laparoscopic procedures. A newly developed telestration system with augmented reality (iSurgeon) allows the instructor to display hand gestures in real-time on the laparoscopic screen in augmented reality to provide visual expert guidance (telestration). This study analysed the effect of telestration guided instructions on gaze behaviour during MIS training. METHODS: In a randomized-controlled crossover study, 40 MIS naive medical students performed 8 laparoscopic tasks with telestration or with verbal instructions only. Pupil Core eye-tracking glasses were used to capture the instructor's and trainees' gazes. Gaze behaviour measures for tasks 1-7 were gaze latency, gaze convergence and collaborative gaze convergence. Performance measures included the number of errors in tasks 1-7 and trainee's ratings in structured and standardized performance scores in task 8 (ex vivo porcine laparoscopic cholecystectomy). RESULTS: There was a significant improvement 1-7 on gaze latency [F(1,39) = 762.5, p < 0.01, ηp2 = 0.95], gaze convergence [F(1,39) = 482.8, p < 0.01, ηp2 = 0.93] and collaborative gaze convergence [F(1,39) = 408.4, p < 0.01, ηp2 = 0.91] upon instruction with iSurgeon. The number of errors was significantly lower in tasks 1-7 (0.18 ± 0.56 vs. 1.94 ± 1.80, p < 0.01) and the score ratings for laparoscopic cholecystectomy were significantly higher with telestration (global OSATS: 29 ± 2.5 vs. 25 ± 5.5, p < 0.01; task-specific OSATS: 60 ± 3 vs. 50 ± 6, p < 0.01). CONCLUSIONS: Telestration with augmented reality successfully improved surgical performance. The trainee's gaze behaviour was improved by reducing the time from instruction to fixation on targets and leading to a higher convergence of the instructor's and the trainee's gazes. Also, the convergence of trainee's gaze and target areas increased with telestration. This confirms augmented reality-based telestration works by means of gaze guidance in MIS and could be used to improve training outcomes.

Robotic-assisted versus laparoscopic bowel anastomoses: randomized crossover in vivo experimental study.

BACKGROUND: Initial learning curves are potentially shorter in robotic-assisted surgery (RAS) than in conventional laparoscopic surgery (LS). There is little evidence to support this claim. Furthermore, there is limited evidence how skills from LS transfer to RAS. METHODS: A randomized controlled, assessor blinded crossover study to compare how RAS naïve surgeons (n = 40) performed linear-stapled side-to-side bowel anastomoses in an in vivo porcine model with LS and RAS. Technique was rated using the validated anastomosis objective structured assessment of skills (A-OSATS) score and the conventional OSATS score. Skill transfer from LS to RAS was measured by comparing the RAS performance of LS novices and LS experienced surgeons. Mental and physical workload was measured with the NASA-task load index (NASA-Tlx) and the Borg-scale. OUTCOMES: In the overall cohort, there were no differences between RAS and LS for surgical performance (A-OSATS, time, OSATS). Surgeons that were naïve in both LS and RAS had significantly higher A-OSATS scores in RAS (Mean (Standard deviation (SD)): LS: 48.0 ± 12.1; RAS: 52.0 ± 7.5); p = 0.044) mainly deriving from better bowel positioning (LS: 8.7 ± 1.4; RAS: 9.3 ± 1.0; p = 0.045) and closure of enterotomy (LS: 12.8 ± 5.5; RAS: 15.6 ± 4.7; p = 0.010). There was no statistically significant difference in how LS novices and LS experienced surgeons performed in RAS [Mean (SD): novices: 48.9 ± 9.0; experienced surgeons: 55.9 ± 11.0; p = 0.540]. Mental and physical demand was significantly higher after LS. CONCLUSION: The initial performance was improved for RAS versus LS for linear stapled bowel anastomosis, whereas workload was higher for LS. There was limited transfer of skills from LS to RAS.

Evidence mapping on how to perform an optimal surgical repair of large hiatal hernias.

BACKGROUND: Symptomatic and large hiatal hernia (HH) is a common disorder requiring surgical management. However, there is a lack of systematic, evidence-based recommendations summarizing recent reviews on surgical treatment of symptomatic HH. Therefore, this systematic review aimed to create evidence mapping on the key technical issues of HH repair based on the highest available evidence. METHODS: A systematic review identified studies on eight key issues of large symptomatic HH repair. The literature was screened for the highest level of evidence (LE from level 1 to 5) according to the Oxford Center for evidence-based medicine's scale. For each topic, only studies of the highest available level of evidence were considered. RESULTS: Out of the 28.783 studies matching the keyword algorithm, 47 were considered. The following recommendations could be deduced: minimally invasive surgery is the recommended approach (LE 1a); a complete hernia sac dissection should be considered (LE 3b); extensive division of short gastric vessels cannot be recommended; however, limited dissection of the most upper vessels may be helpful for a floppy fundoplication (LE 1a); vagus nerve should be preserved (LE 3b); a dorso-ventral cruroplasty is recommended (LE 1b); routine fundoplication should be considered to prevent postoperative gastroesophageal reflux (LE 2b); posterior partial fundoplication should be favored over other forms of fundoplication (LE 1a); mesh augmentation is indicated in large HH with paraesophageal involvement (LE 1a). CONCLUSION: The current evidence mapping is a reasonable instrument based on the best evidence available to guide surgeons in determining optimal symptomatic and large HH repair.

[Status Quo of Surgical Navigation]. / Update zur Navigation im OP-Saal.

Surgical navigation, also referred to as computer-assisted or image-guided surgery, is a technique that employs a variety of methods - such as 3D imaging, tracking systems, specialised software, and robotics to support surgeons during surgical interventions. These emerging technologies aim not only to enhance the accuracy and precision of surgical procedures, but also to enable less invasive approaches, with the objective of reducing complications and improving operative outcomes for patients. By harnessing the integration of emerging digital technologies, surgical navigation holds the promise of assisting complex procedures across various medical disciplines. In recent years, the field of surgical navigation has witnessed significant advances. Abdominal surgical navigation, particularly endoscopy, laparoscopic, and robot-assisted surgery, is currently undergoing a phase of rapid evolution. Emphases include image-guided navigation, instrument tracking, and the potential integration of augmented and mixed reality (AR, MR). This article will comprehensively delve into the latest developments in surgical navigation, spanning state-of-the-art intraoperative technologies like hyperspectral and fluorescent imaging, to the integration of preoperative radiological imaging within the intraoperative setting.

Development of biotissue training models for anastomotic suturing in pancreatic surgery.

BACKGROUND: Anastomotic suturing is the Achilles heel of pancreatic surgery. Especially in laparoscopic and robotically assisted surgery, the pancreatic anastomosis should first be trained outside the operating room. Realistic training models are therefore needed. METHODS: Models of the pancreas, small bowel, stomach, bile duct, and a realistic training torso were developed for training of anastomoses in pancreatic surgery. Pancreas models with soft and hard textures, small and large ducts were incrementally developed and evaluated. Experienced pancreatic surgeons (n = 44) evaluated haptic realism, rigidity, fragility of tissues, and realism of suturing and knot tying. RESULTS: In the iterative development process the pancreas models showed high haptic realism and highest realism in suturing (4.6 ± 0.7 and 4.9 ± 0.5 on 1-5 Likert scale, soft pancreas). The small bowel model showed highest haptic realism (4.8 ± 0.4) and optimal wall thickness (0.1 ± 0.4 on -2 to +2 Likert scale) and suturing behavior (0.1 ± 0.4). The bile duct models showed optimal wall thickness (0.3 ± 0.8 and 0.4 ± 0.8 on -2 to +2 Likert scale) and optimal tissue fragility (0 ± 0.9 and 0.3 ± 0.7). CONCLUSION: The biotissue training models showed high haptic realism and realistic suturing behavior. They are suitable for realistic training of anastomoses in pancreatic surgery which may improve patient outcomes.