Robot-assisted oesophagectomy (Ivor-Lewis) for a complex stenosis previously managed by open gastrostomy tube placement.

A man in his late 50s presented with severe dysphagia caused by a complex refractory benign stenosis that was completely obstructing the middle oesophagus. The patient was unsatisfied with the gastrostomy tube placed via laparotomy as a long-term solution. Therefore, we performed robot-assisted minimally invasive oesophagectomy (video). Mobilisation of the stomach and gastric conduit preparation were more difficult due to the previously inserted gastrostomy tube; thus, the conduit blood supply was assessed using indocyanine green fluorescence. After an uncomplicated course, the patient was referred directly to inpatient rehabilitation on the 16th postoperative day. At 9 months after surgery, the motivated patient returned to full-time work and achieved level 7 on the functional oral intake scale (total oral diet, with no restrictions). At the 1-year follow-up, he positively confirmed all nine key elements of a good quality of life after oesophagectomy.

Keep it simple: a crosshair on the screen during proctored laparoscopic surgeries.

INTRODUCTION: Inside the operating room, experts use verbal instructions to guide surgical novices through laparoscopic procedures. In this study, we evaluated the use of a crosshair attached to the video monitor, as a hands-free pointing tool to simplify instructions during operation. METHODS: Ten surgical novices performed two elective laparoscopic cholecystectomies within a week of each other, randomized such that one was performed with and the other without using the crosshair. Directly after operation, questionnaires were completed by the novices and the consultant surgeons. Measures including the comprehensibility of instructions, subjective feeling of safety during preparation, time delays due to different instruction options, and disruptive influence while instructors used the crosshair. Differences in operative performance were evaluated based on the global operative assessment of laparoscopic skills (GOALS) scores. RESULTS: When the crosshair was used, surgical novices had a better understanding of which anatomical structure should be shown (p = 0.028). Operating time (p = 0.222) and feeling of confidence during preparation did not differ with versus without crosshair use (p = 0.081). All participants stated that the crosshair did not negatively affect the field of vision. In terms of the median GOALS score, the operative performance was improved when the crosshair was used compared with verbal instructions only (median 15, IQR (11; 21) vs. median 12, IQR (5; 19), p < 0.001). CONCLUSION: The crosshair is a simple, inexpensive, and widely available method to improve communication between instructors and novices in everyday training.

Real-Time Augmented Reality Annotation for Surgical Education during Laparoscopic Surgery: Results from a Single-Center Randomized Controlled Trial and Future Aspects.

BACKGROUND: We developed an interactive augmented reality tool (HoloPointer) that enables real-time annotation on a laparoscopy monitor for intraoperative guidance. This application operates exclusively via verbal commands and head movements to ensure a sterile workflow. STUDY DESIGN: Purpose of this randomized controlled clinical trial was to evaluate the integration of this new technology into the operating room. This prospective single-center study included 32 elective laparoscopic cholecystectomies (29 surgical teams, 15 trainees, and 13 trainers). The primary objective and assessment measure was the HoloPointer's influence on surgical performance (subjective assessment, global operative assessment of laparoscopic skills [GOALS] and critical view of safety [CVS]). The secondary objectives and outcome variables were its influence on operation time, quality of assistance (5-point Likert scale), and user-friendliness (system usability scale, 0 to 100 points). RESULTS: Gestural corrections were reduced by 59.4% (4.6 SD 8.1 vs 1.9 SD 4.7, p > 0.05) and verbal corrections by 36.1% (17.8 SD 12.9 vs 11.4 SD 8.1, p > 0.05). Subjective surgical performance could be improved by 84.6% of participants. No statistically significant differences were observed for objective parameters GOALS, CVS, and operation time. In the system usability scale, the application achieved an average score of 72.5 SD 16.3 (good user-friendliness). Of the participants, 69.2% wanted to use the HoloPointer more frequently. CONCLUSIONS: The majority of trainees improved their surgical performance using the HoloPointer in elective laparoscopic cholecystectomies, and the rate of classic but potentially misleading corrections was noticeably reduced. The HoloPointer has the potential to improve education in minimally invasive surgery.

[Low anterior resection syndrome]. / Tiefes anteriores Resektionssyndrom: Fälle aus der Praxis.

In daily practice, the presentation, recording, prophylaxis and therapy of the low anterior resection syndrome (LARS) are of great importance for patients, relatives, therapists, service providers and cost bearers. Interdisciplinarity, interprofessionalism and cross-sector care as well as self-help are important prerequisites that must be coordinated in relation to the patient. Examples from a colorectal cancer centre certified by the German Cancer Society are intended to underline this and complement the special issue of coloproctology.

Laparoscopic Electromyography and Electrostimulation of the Gastrointestinal Tract Before Placement of Theranostic Devices.

NEED: Electrical stimulation (ES) is a promising therapy for multisegmental gastrointestinal (GI) motility disorders such as gastroparesis with slow-transit constipation or chronic intestinal pseudo-obstruction. Wireless communicating GI devices for smart sensing and ES-based motility modulation will soon be available. Before placement, a potential benefit for each GI segment must be intraoperatively assessed. TECHNICAL SOLUTION: A minimally invasive multisegmental electromyography (EMG) analysis with ES of the GI tract is required. PROOF OF CONCEPT: Two porcine experiments were performed with a laparoscopic setup. Multiple hook-needle electrodes were subserosally applied in the stomach, duodenum, jejunum, ileum, and colon. EMG signals were acquired for computer-assisted motility analysis. Gastric ES, duodenal ES, jejunal ES, ileal ES, and colonic ES were applied. NEXT STEPS: Further technological and rapid regulatory solutions are desired to initialize a clinical trial of the next generation devices in the near future. CONCLUSION: We demonstrate a laparoscopic strategy with EMG analysis and ES of multiple GI segments. Thus, GI function may be evaluated before theranostic devices are placed. Extended GI resection or organ transplantation may be delayed or even avoided in affected patients.

Pelvic Intraoperative Neuromonitoring Prevents Dysfunction in Patients With Rectal Cancer: Results From a Multicenter, Randomized, Controlled Clinical Trial of a NEUROmonitoring System (NEUROS).

OBJECTIVE: This NEUROmonitoring System (NEUROS) trial assessed whether pelvic intraoperative neuromonitoring (pIONM) could improve urogenital and ano-(neo-)rectal functional outcomes in patients who underwent total mesorectal excisions (TMEs) for rectal cancer. BACKGROUND: High-level evidence from clinical trials is required to clarify the benefits of pIONM. METHODS: NEUROS was a 2-arm, randomized, controlled, multicenter clinical trial that included 189 patients with rectal cancer who underwent TMEs at 8 centers, from February 2013 to January 2017. TMEs were performed with pIONM (n=90) or without it (control, n=99). The groups were stratified according to neoadjuvant chemoradiotherapy and sex, with blocks of variable length. Data were analyzed according to a modified intention-to-treat protocol. The primary endpoint was a urinary function at 12 months after surgery, assessed with the International Prostate Symptom Score, a patient-reported outcome measure. Deterioration was defined as an increase of at least 5 points from the preoperative score. Secondary endpoints were sexual and anorectal functional outcomes, safety, and TME quality. RESULTS: The intention-to-treat analysis included 171 patients. Marked urinary deterioration occurred in 22/171 (13%) patients, with significantly different incidence between groups (pIONM: n=6/82, 8%; control: n=16/89, 19%; 95% confidence interval, 12.4-94.4; P =0.0382). pIONM was associated with better sexual and ano-(neo)rectal function. At least 1 serious adverse event occurred in 36/88 (41%) in the pIONM group and 53/99 (54%) in the control group, none associated with the study treatment. The groups had similar TME quality, surgery times, intraoperative complication incidence, and postoperative mortality. CONCLUSION: pIONM is safe and has the potential to improve functional outcomes in rectal cancer patients undergoing TME.

Virtual reality and 3D printing improve preoperative visualization of 3D liver reconstructions-results from a preclinical comparison of presentation modalities and user's preference.

BACKGROUND: Preoperative three-dimensional (3D) reconstructions for liver surgery planning have been shown to be effective in reduction of blood loss and operation time. However, the role of the 'presentation modality' is not well investigated. We present the first study to compare 3D PDFs, 3D printed models (PR) and virtual reality (VR) 3D models with regard to anatomical orientation and personal preferences in a high volume liver surgery center. METHODS: Thirty participants, 10 medical students, 10 residents, 5 fellows and 5 hepatopancreatobiliary (HPB) experts, assigned the tumor-bearing segments of 20 different patient's individual liver reconstructions. Liver models were presented in a random order in all modalities. Time needed to specify the tumor location was recorded. In addition, a score was calculated factoring in correct, wrong and missing segment assignments. Furthermore, standardized test/questionnaires for spatial thinking and seeing, vegetative side effects and usability were completed. RESULTS: Participants named significantly more correct segments in VR (P=0.040) or PR (P=0.036) compared to PDF. Tumor assignment was significantly shorter with 3D PR models compared to 3D PDF (P<0.001) or VR application (P<0.001). Regardless of the modality, HPB experts were significantly faster (24±8 vs. 35±11 sec; P=0.014) and more often correct (0.87±0.12 vs. 0.83±0.15; P<0.001) than medical students. Test results for spatial thinking and seeing had no influence on time but on correctness of tumor assignment. Regarding usability and user experience the VR application achieved the highest scores without causing significant vegetative symptoms and was also the most preferred method (n=22, 73.3%) because of the multiple functions like scaling and change of transparency. Ninety percent (n=27) stated that this application can positively influence the operation planning. CONCLUSIONS: 3D PR models and 3D VR models enable a better and partially faster anatomical orientation than reconstructions presented as 3D PDFs. User's preferred the VR application over the PR models and PDF. A prospective trial is needed to evaluate the different presentation modalities regarding intra- and postoperative outcomes.

Comparative analysis of nuclear and mitochondrial DNA from tissue and liquid biopsies of colorectal cancer patients.

The current standard for molecular profiling of colorectal cancer (CRC) is using resected or biopsied tissue specimens. However, they are limited regarding sampling frequency, representation of tumor heterogeneity, and sampling can expose patients to adverse side effects. The analysis of cell-free DNA (cfDNA) from blood plasma, which is part of a liquid biopsy, is minimally invasive and in principle enables detection of all tumor-specific mutations. Here, we analyzed cfDNA originating from nucleus and mitochondria and investigated their characteristics and mutation status in a cohort of 18 CRC patients and 10 healthy controls using targeted next-generation sequencing (NGS) and digital PCR. Longitudinal analyses of nuclear cfDNA level and size during chemotherapy revealed a decreasing cfDNA content and a shift from short to long fragments, indicating an appropriate therapy response, while shortened cfDNAs and increased cfDNA content corresponded with tumor recurrence. Comparative NGS analysis of nuclear tissue and plasma DNA demonstrated a good patient-level concordance and cfDNA revealed additional variants in three of the cases. Analysis of mitochondrial cfDNA surprisingly revealed a higher plasma copy number in healthy subjects than in CRC patients. These results highlight the potential clinical utility of liquid biopsies in routine diagnostics and surveillance of CRC patients as complementation to tissue biopsies or as an attractive alternative in cases where tissue biopsies are risky or the quantity/quality does not allow testing.

Using virtual 3D-models in surgical planning: workflow of an immersive virtual reality application in liver surgery.

PURPOSE: Three-dimensional (3D) surgical planning is widely accepted in liver surgery. Currently, the 3D reconstructions are usually presented as 3D PDF data on regular monitors. 3D-printed liver models are sometimes used for education and planning. METHODS: We developed an immersive virtual reality (VR) application that enables the presentation of preoperative 3D models. The 3D reconstructions are exported as STL files and easily imported into the application, which creates the virtual model automatically. The presentation is possible in "OpenVR"-ready VR headsets. To interact with the 3D liver model, VR controllers are used. Scaling is possible, as well as changing the opacity from invisible over transparent to fully opaque. In addition, the surgeon can draw potential resection lines on the surface of the liver. All these functions can be used in a single or multi-user mode. RESULTS: Five highly experienced HPB surgeons of our department evaluated the VR application after using it for the very first time and considered it helpful according to the "System Usability Scale" (SUS) with a score of 76.6%. Especially with the subitem "necessary learning effort," it was shown that the application is easy to use. CONCLUSION: We introduce an immersive, interactive presentation of medical volume data for preoperative 3D liver surgery planning. The application is easy to use and may have advantages over 3D PDF and 3D print in preoperative liver surgery planning. Prospective trials are needed to evaluate the optimal presentation mode of 3D liver models.

[Surgical Education in the Digital Age - Virtual Reality, Augmented Reality and Robotics in the Medical School]. / Chirurgische Ausbildung im digitalen Zeitalter ­ Virtual Reality, Augmented Reality und Robotik im Medizinstudium.

BACKGROUND: The digital transformation of healthcare is changing the medical profession. Augmented/Virtual Reality (AR/VR) and robotics are being increasingly used in different clinical contexts and require supporting education and training, which must begin within the medical school. There is currently a large discrepancy between the high demand and the number of scientifically proven concepts. The aim of this thesis was the conceptual design and structured evaluation of a newly developed learning/teaching concept for the digital transformation of medicine, with a special focus on the influence of surgical teaching. METHODS: Thirty-five students participated in three courses of the blended learning curriculum "Medicine in the digital age". The 4th module of this course deals with virtual reality, augmented reality and robotics in surgery. It is divided into the following course parts: (1) immersive surgery simulation of a laparoscopic cholecystectomy, (2) liver surgery planning using AR/VR, (3) basic skills on the VR simulator for robotic surgery, (4) collaborative surgery planning in virtual space and (5) expert discussion. After completing the overall curriculum, a qualitative and quantitative evaluation of the course concept was carried out by means of semi-structured interviews and standardised pre-/post-evaluation questionnaires. RESULTS: In the qualitative evaluation procedure of the interviews, 79 text statements were assigned to four main categories. The largest share (35%) was taken up by statements on the "expert discussion", which the students consider to be an elementary part of the course concept. In addition, the students perceived the course as a horizon-widening "learning experience" (29% of the statements) with high "practical relevance" (27%). The quantitative student evaluation shows a positive development in the three sub-competences knowledge, skills and attitude. CONCLUSION: Surgical teaching can be profitably used to develop digital skills. The speed of the change process of digital transformation in the surgical specialty must be considered. Curricular adaptation should be anchored in the course concept.

HoloPointer: a virtual augmented reality pointer for laparoscopic surgery training.

PURPOSE: In laparoscopic surgery training, experts guide novice physicians to desired instrument positions or indicate relevant areas of interest. These instructions are usually given via verbal communication or using physical pointing devices. To facilitate a sterile work flow and to improve training, new guiding methods are needed. This work proposes to use optical see-through augmented reality to visualize an interactive virtual pointer on the laparoscopic. METHODS: After an interdisciplinary development, the pointer's applicability and feasibility for training was evaluated and it was compared to a standard condition based on verbal and gestural communication only. In this study, ten surgical trainees were guided by an experienced trainer during cholecystectomies on a laparoscopic training simulator. All trainees completed a virtual cholecystectomy with and without the interactive virtual pointer in alternating order. Measures included procedure time, economy of movement and error rates. RESULTS: Results of standardized variables revealed significantly improved economy of movement (p = 0.047) and error rates (p = 0.047), as well as an overall improved user performance (Total z-score; p = 0.031) in conditions using the proposed method. CONCLUSION: The proposed HoloPointer is a feasible and applicable tool for laparoscopic surgery training. It improved objective performance metrics without prolongation of the task completion time in this pre-clinical setup.

Toward interprofessional team training for surgeons and anesthesiologists using virtual reality.

PURPOSE: In this work, a virtual environment for interprofessional team training in laparoscopic surgery is proposed. Our objective is to provide a tool to train and improve intraoperative communication between anesthesiologists and surgeons during laparoscopic procedures. METHODS: An anesthesia simulation software and laparoscopic simulation software are combined within a multi-user virtual reality (VR) environment. Furthermore, two medical training scenarios for communication training between anesthesiologists and surgeons are proposed and evaluated. Testing was conducted and social presence was measured. In addition, clinical feedback from experts was collected by following a think-aloud protocol and through structured interviews. RESULTS: Our prototype is assessed as a reasonable basis for training and extensive clinical evaluation. Furthermore, the results of testing revealed a high degree of exhilaration and social presence of the involved physicians. Valuable insights were gained from the interviews and the think-aloud protocol with the experts of anesthesia and surgery that showed the feasibility of team training in VR, the usefulness of the system for medical training, and current limitations. CONCLUSION: The proposed VR prototype provides a new basis for interprofessional team training in surgery. It engages the training of problem-based communication during surgery and might open new directions for operating room training.

Robotic Setup Promises Consistent Effects of Multilocular Gastrointestinal Electrical Stimulation: First Results of a Porcine Study.

BACKGROUND: Electrical stimulation (ES) of several gastrointestinal (GI) segments is a promising therapeutic option for multilocular GI dysmotility, but conventional surgical access by laparotomy involves a high degree of tissue trauma. We evaluated a minimally invasive surgical approach using a robotic surgical system to perform electromyographic (EMG) recordings and ES of several porcine GI segments, comparing these data to an open surgical approach by laparotomy. MATERIALS AND METHODS: In 5 acute porcine experiments, we placed multiple electrodes on the stomach, duodenum, jejunum, ileum, and colon. Three experiments were performed with a median laparotomy and 2 others using a robotic platform. Multichannel EMGs were recorded, and ES was sequentially delivered with 4 ES parameters to the 5 target segments. We calculated pre- and poststimulatory spikes per minute (Spm) and performed a statistical Poisson analysis. RESULTS: Electrode placement was achieved in all cases without complications. Increased technical and implantation time were required to achieve the robotic electrode placement, but invasiveness was markedly reduced in comparison to the conventional approach. The highest calculated (c)Spm values were found in the poststimulatory period of the small bowel with both the conventional and robotic approaches. Six of the 20 Poisson test results in the open setup reached statistical significance and 12 were significant in the robotic experiments. CONCLUSIONS: The robotic setup was less invasive, revealed more consistent effects of multilocular ES in several GI segments, and is a promising option for future preclinical and clinical studies of GI motility disorders.

Quality-based assessment of camera navigation skills for laparoscopic fundoplication.

Laparoscopic fundoplication is considered the gold standard surgical procedure for the treatment of symptomatic hiatus hernia. Studies on surgical performance in minimally invasive hiatus hernia repair have neglected the role of the camera assistant so far. The current study was designed to assess the applicability of the structured assessment of laparoscopic assistance skills (SALAS) score to laparoscopic fundoplication as an advanced and commonly performed laparoscopic upper GI procedure. Randomly selected laparoscopic fundoplications (n = 20) at a single institute were evaluated. Four trained reviewers independently assigned SALAS scoring based on synchronized video and voice recordings. The SALAS score (5-25 points) consists of five key aspects of laparoscopic camera navigation as previously described. Experience in camera assistance was defined as at least 100 assistances in complex laparoscopic procedures. Nine different surgical teams, consisting of five surgical residents, three fellows, and two attending physicians, were included. Experienced and inexperienced camera assistants were equally distributed (10/10). Construct validity was proven with a significant discrimination between experienced and inexperienced camera assistants for all reviewers (P < 0.05). The intraclass correlation coefficient of 0.897 demonstrates the score's low interrater variability. The total operation time decreases with increasing SALAS score, not reaching statistical significance. The applied SALAS score proves effective by discriminating between experienced and inexperienced camera assistants in an upper GI surgical procedure. This study demonstrates the applicability of the SALAS score to a more advanced laparoscopic procedure such as fundoplication enabling future investigations on the influence of camera navigation on surgical performance and operative outcome.

Da Vinci Single-Port robot-assisted transanal mesorectal excision: a promising preclinical experience.

INTRODUCTION: Robotic single-port platforms represent a viable option for advanced surgical procedures. This preclinical study investigated the dual-field, single-port, robot-assisted transanal total mesorectal excision (taTME). TECHNIQUE: In a male human cadaver, we employed the novel da Vinci® SP™ Surgical System, sequentially, to realize the transanal and abdominal parts of the taTME procedure. We evaluated the feasibility of the one-team approach. RESULTS: We showed that single-port access for the taTME was technically feasible with the current da Vinci® SP™ Surgical System in both surgical fields. The total console times were 189 min for the juxta-anal purse-string suture placement, partial intersphincteric resection, and bottom-up mesorectal dissection to where it meets the peritoneal reflection and 43 min for the abdominal procedure. A good quality specimen was achieved. The surgeon comfort was high during simulated surgery. The task load was highly acceptable (NASA-TLX global score: 35), even though it was the surgeon's first use of this platform. CONCLUSION: This preclinical study demonstrated that the robotic, single-port taTME was feasible and could be performed with the da Vinci® SP™ Surgical System, beginning at the level of the dentate line. Further simulations are necessary to confirm this promising approach.

Translational development and pre-clinical evaluation of prototype gastrointestinal mock-up devices: only robotic placement of plastic?

Background: The aim of this study was to address the vision of wireless theranostic devices distributed along the gastrointestinal (GI) tract by defining design requirements, developing prototype mock-ups, and establishing a minimally invasive surgical approach for the implantation process.Methods: Questionnaires for contextual analysis and use case scenarios addressing the technical issues of an implantable GI device, a possible scenario for implantation, preparation and calibration of a device, and therapeutic usage by professionals and patients were completed and discussed by an interdisciplinary team of surgeons, engineers, and product designers. Two acute porcine experiments were conducted with a robotic surgical system under general anaesthesia.Results: A variety of requirements for the design and implantation of implantable devices for modulating GI motility were defined. Five prototype implant mock-ups were three-dimensional (3D)-printed from black polymer material (width 22.32 mm, height 7.66 mm) and successfully implanted on the stomach, duodenum, jejunum, ileum, and colon using the robotic surgical system, without any complications.Conclusions: Our study shows the development and successful pre-clinical evaluation of a reliable device design with a minimally invasive implantation approach. Several stages of device development, including pre-clinical tests, characterisation of clinical requirements, regulatory affairs, and marketing issues should be managed side by side.

Local, semi-automatic, three-dimensional liver reconstruction or external provider? An analysis of performance and time expense.

PURPOSE: In hepatobiliary surgery, preoperative three-dimensional reconstruction based on CT or MRI can be provided externally or by local, semi-automatic software. We analyzed the time expense and quality of external versus local three-dimensional reconstructions. METHODS: Three first-year residents reconstructed data from 20 patients with liver pathologies using a local, semi-automatic, server-based program. Initially, five randomly selected patient datasets were segmented, with the visualization of an established external company available for comparison at all times (learning phase). The other fifteen cases were compared with the external datasets after completing local reconstruction (control phase). Total time expense/case and for specific manual and semi-automated reconstruction steps were recorded. Segmentation quality was analyzed by testing the equivalence for liver and tumor volumes, portal vein sectors, and hepatic vein territories. RESULTS: The median total reconstruction time was reduced from 2.5 h (learning phase) to 1.5 h (control phase) (- 42%; p < 0.001). Comparing the total and detailed liver volumes (sectors and territories) as well as the tumor volumes in the control phase equivalence was proven. In addition, a highly significant correlation between the external and local analysis was obtained over all analyzed segments with a very high ICC (median [IQR]: 0.98 [0.97; 0.99]; p < 0.01). CONCLUSION: Local, semi-automatic reconstruction performed by inexperienced residents was feasible with an expert level time expense and the quality of the three-dimensional images was comparable with those from an external provider.

Fecal incontinence after total mesorectal excision for rectal cancer-impact of potential risk factors and pelvic intraoperative neuromonitoring.

BACKGROUND: Fecal incontinence frequently occurs after total mesorectal excision for rectal cancer. This prospective study analyzed predictive factors and the impact of pelvic intraoperative neuromonitoring at different follow-up intervals. METHODS: Fifty-two patients were included undergoing total mesorectal excision for rectal cancer, and 29 under control of pelvic intraoperative neuromonitoring. Fecal incontinence was assessed using the Wexner Score at 3 and 6 months after stoma closure (follow-ups 1 and 2) as well as 1 and 2 years after surgery (follow-ups 3 and 4). Risk factors were identified by means of logistic regression. RESULTS: New onset of fecal incontinence was significantly lower in the neuromonitoring group at each follow-up (follow-up 1: 2 of 29 patients (7%) vs. 8 of 23 (35%), (p = 0.014); follow-up 2: 3 of 29 (10%) vs. 9 of 23 (39%), (p = 0.017); follow-up 3: 5 of 29 (17%) vs. 11 of 23 (48%), p = 0.019; follow-up 4: 6 of 28 (21%) vs. 11 of 22 (50%), p = 0.035). Non-performance of neuromonitoring was found to be an independent predictor for fecal incontinence throughout the survey. Neoadjuvant chemoradiotherapy was an independent predictor in the further course 1 and 2 years after surgery. CONCLUSIONS: Performance of pelvic intraoperative neuromonitoring is associated with significantly lower rates of fecal incontinence. Neoadjuvant chemoradiotherapy was found to have negative late effects. This became evident 1 year after surgery.

Higher quality camera navigation improves the surgeon's performance: Evidence from a pre-clinical study.

INTRODUCTION: To objectively assess the quality of laparoscopic camera navigation (LCN), the structured assessment of LCN skills (SALAS) score was developed and validated for laparoscopic cholecystectomy. The aim of this pre-clinical study was to investigate the influence of LCN on surgical performance during virtual cholecystectomy (vCHE) using this score. METHODS: A total of 84 medical students were included in this prospective study. Individual characteristics were assessed with questionnaires. Participants completed a structured 2-day training course on a validated virtual reality laparoscopic simulator. At the end of the course, all students took over LCN during vCHE, all performed by the same surgeon. The numbers of errors regarding centering, horizon adjustment and instrument visualisation as well as manual and verbal corrections by the surgeon were recorded to calculate the SALAS score (range 5-25) to investigate the influence of LCN on surgical performance. The study population was divided by the recorded SALAS score into low and medium performers (Group A; 1st-3rd quartile; n = 60) and high performers (Group B, 4th quartile, n = 21). RESULTS: The SALAS score of the camera assistant correlates positively with the surgeon's overall performance in vCHE (P < 0.001), and the surgeon's virtual laparoscopic performance was significantly better in Group B (P < 0.001). Moreover, a significantly shorter operation time during vCHE was shown for Group B (Median (IQR); Group A: 508 s [429 s; 601 s]; Group B: 422 s [365 s; 493 s]; P = 0.001). Frequent gaming and a higher self-confidence to assist during a basic laparoscopic procedure were associated with a higher SALAS score (P = 0.013). CONCLUSION: In this pre-clinical setting, the surgeon's virtual performance is significantly influenced by the LCN quality. LCN by high performers resulted in a shorter operation time and a lower error rate.

[Prerequisites for Safe Implementation of Transanal Total Mesorectal Excision]. / Transanale totale mesorektale Exzision ­ Voraussetzungen zur sicheren Implementierung.

Transanal total mesorectal excision (TaTME) is an innovative and technically demanding surgical approach for the treatment of rectal cancer. This review summarises the international consensus statements on prerequisites and training requirements for safe implementation of this complex procedure. Recommendations will be discussed on the basis of the published surveys from dedicated training centres. Furthermore, experience is shared on mentored TaTME cadaveric courses (video) and an initial clinical series of 102 TaTMEs. The procedure should be performed primarily by postgraduate colorectal surgeons. Initially, a structured training program at designated training centers is mandatory. Cadaver training and proctoring are the central elements required to ensure safe implementation of TaTME in clinical practice. However, validation of TaTME training concepts needs further work. Evaluation of the first pioneering series indicates a learning phase with at least 40 operations. Above the cut-off, lower complication rates and acceptable quality of specimen are achieved. In our series, morbidity decreased significantly (Clavien-Dindo ≥ III: 29 vs. 9%). With the indication for TaTME, we find a median of 6 risk factors (4 - 8) for an unfavourable outcome after abdominal TME alone. Only high volume centres with a concentration of appropriately selected patients could aim for a proposed TaTME frequency of 20 per year. Structured training programs for TaTME are justified and must be completed before implementation in clinical practice. The case volume effect for the learning curve and individual patient selection are crucial and support the concentration of the new method in high volume centres.