Surgical reporting for laparoscopic cholecystectomy based on phase annotation by a convolutional neural network (CNN) and the phenomenon of phase flickering: a proof of concept.

PURPOSE: Surgical documentation is an important yet time-consuming necessity in clinical routine. Beside its core function to transmit information about a surgery to other medical professionals, the surgical report has gained even more significance in terms of information extraction for scientific, administrative and judicial application. A possible basis for computer aided reporting is phase detection by convolutional neural networks (CNN). In this article we propose a workflow to generate operative notes based on the output of the TeCNO CNN. METHODS: Video recordings of 15 cholecystectomies were used for inference. The annotation of TeCNO was compared to that of an expert surgeon (HE) and the algorithm based annotation of a scientist (HA). The CNN output then was used to identify aberrance from standard course as basis for the final report. Moreover, we assessed the phenomenon of 'phase flickering' as clusters of incorrectly labeled frames and evaluated its usability. RESULTS: The accordance of the HE and CNN was 79.7% and that of HA and CNN 87.0%. 'Phase flickering' indicated an aberrant course with AUCs of 0.91 and 0.89 in ROC analysis regarding number and extend of concerned frames. Finally, we created operative notes based on a standard text, deviation alerts, and manual completion by the surgeon. CONCLUSION: Computer-aided documentation is a noteworthy use case for phase recognition in standardized surgery. The analysis of phase flickering in a CNN's annotation has the potential of retrieving more information about the course of a particular procedure to complement an automated report.

[Image-based supportive measures for future application in surgery]. / Bildbasierte Unterstützungsmethoden für die zukünftige Anwendung in der Chirurgie.

BACKGROUND: The development of assistive technologies will become of increasing importance in the coming years and not only in surgery. The comprehensive perception of the actual situation is the basis of every autonomous action. Different sensor systems can be used for this purpose, of which video-based systems have a special potential. METHOD: Based on the available literature and on own research projects, central aspects of image-based support systems for surgery are presented. In this context, not only the potential but also the limitations of the methods are explained. RESULTS: An established application is the phase detection of surgical interventions, for which surgical videos are analyzed using neural networks. Through a time-based and transformative analysis the results of the prediction could only recently be significantly improved. Robotic camera guidance systems will also use image data to autonomously navigate laparoscopes in the near future. The reliability of the systems needs to be adapted to the high requirements in surgery by means of additional information. A comparable multimodal approach has already been implemented for navigation and localization during laparoscopic procedures. For this purpose, video data are analyzed using various methods and these data are fused with other sensor modalities. DISCUSSION: Image-based supportive methods are already available for various tasks and will become an important aspect for the surgery of the future; however, in order to be able to be reliably implemented for autonomous functions, they must be embedded in multimodal approaches in the future in order to provide the necessary security.

MIEO: a micro-invasive endoscopic operation port system for transluminal interventions-an acute and survival porcine study.

BACKGROUND: A reliable and sterile access through the intestinal wall to ease flexible endoscopic transluminal interventions is still appealing but lacks a suitable port system. METHODS: In a granted industry cooperation, we developed the MIEO-Port, a flexible three components overtube system that provides a temporary hermetic sealing of the intestinal wall to allow endoscopic disinfection and manipulation to gain access to the abdominal cavity. The port features an innovative head part which allows for coupling the port to the intestinal wall by vacuum suction and for controlled jetting the isolated intestinal surface with a disinfectant. The device was tested in vivo in 6 pigs for acute and long-term usability. All animal tests were approved by the local ethics committee. RESULTS: In the acute experiment, the port system supported sealed endoscopic mucosa resection and transluminal cholecystectomy. In the survival study on 5 animals, the MIEO-Port proved its reliability after transcolonic peritoneoscopy. In one animal, a port dislocation occurred after extensive retroperitoneal preparation, one animal revealed bacterial contamination at necropsy; however, all animals showed a favourable course over ten days and offered no signs of peritonitis or abscedation during post-mortem examination. DISCUSSION: To the best of our knowledge, the MIEO-Port system is the first device to provide a reliable and sterile flexible access to the peritoneal cavity that can be used throughout the entire gastrointestinal tract regardless of the access route and which combines hermetic sealing with local sterilization. Further studies are warranted.

[Artificial intelligence in general and visceral surgery]. / Künstliche Intelligenz in der Allgemein- und Viszeralchirurgie.

Artificial intelligence procedures will find special fields of application also in general and visceral surgery. These will not only be limited to intraoperative surgical applications but also extend to perioperative processes, education and training as well as to future scientific developments. Major impulses are to be expected in decision support systems, cognitive collaborative interventional environments and in evidence-based knowledge acquisition models; however, the implementation into the daily practice not only requires profound insights into the field of informatics and computer science but also a comprehensive knowledge of the surgical domain. Accordingly, the future implementation of artificial intelligence in surgery requires a new culture of collaboration between surgeons and researchers/computer scientists.

[Digitalization in surgery : What surgeons currently think and know about it-results of an online survey]. / Digitalisierung in der Chirurgie : Was Chirurgen darüber denken und was sie wissen ­ Ergebnisse einer Onlineumfrage.

BACKGROUND: The digitalization process is currently on everyone's lips and sweeping changes in the field of public health and especially in surgery are to be expected within the next few years. Besides general issues, such as electronic health records and medical information systems, artificial intelligence, robotics and model-based surgery will decisively impact on the daily routine. In order to provide the necessary knowledge base, to point out related risks and chances and also to define fields of action for surgery, the German Society of Surgery commissioned a position paper on digitalization. A first appraisal in form of an online survey is the subject of this article. METHODS: This article is based on an online survey of the members of the German Society of Surgery and selected members of other related societies. The survey asked for the members' personal assessment concerning different aspects of the digitalization process and the respective state of knowledge as well as the impact on the field of surgery. RESULTS: A total of 296 members contributed to this survey. According to their assessment, digitalization in surgery is currently associated with terms such as electronic health records and medical information systems but they also assume a relevant influence on their own activities and on the fields of interventional medicine and surgery. A relevant need for improvement of the current state of knowledge was highlighted, not only for general aspects of digitalization but also for surgically relevant issues in particular. The vast majority of interviewed members saw digitalization more as a chance for improvement than as a risk factor. CONCLUSION: According to the views of interviewed members of the German Society of Surgery the process of digital transformation will significantly impact the field of surgery. All those involved should feel responsible to contribute to and guide this process in order to maintain the surgically inherent requirements and to protect patient safety. The position paper on digitalization can serve as a basis and should define concrete recommendations for action. In the sense of an academic approach the new possibilities should be critically evaluated with respect to suitability and should be exclusively confined to applications that are beneficial to ourselves and to our patients.

[Model-based treatment in surgery]. / Modellgestützte Therapie in der Chirurgie.

BACKGROUND: The "magic triangle" in surgery and other disciplines consists of the demand for increasingly gentler forms of treatment, simultaneous cost reduction and the fundamental primacy of improving the quality of results. The digitalization of medicine offers a promising opportunity to do justice to this, also in the sense of "Surgery 4.0". The aim is to create a cognitive, collaborative diagnostics and treatment environment to support the surgeon. METHODS: In the sense of a "theory building" for analysis and planning, process modeling is the cornerstone for modern treatment planning. The main distinction is made between the patient model and the treatment model. The course of the actual surgical treatment can also be modeled: in principle it is possible to describe the course of an operation in such fine detail that the surgical procedure can be mapped and reproduced down to each single step, such as a single implementation of forceps. Basically, this has already been achieved. So-called neural networks also open up completely new forms of knowledge acquisition, machine learning and flexible reaction to nearly all conceivable possibilities in highly complex processes. CONCLUSION: "Digitalization" is a necessary development in surgery. It offers not only countless possibilities to support the surgeon in the field of activity but also the chance of more precise data acquisition with respect to academic surgery. Modeling is an indispensable part of this and must be rigorously implemented and further developed.

[Robotics and augmented reality : Current state of development and future perspectives]. / Robotik und "augmented reality" : Aktueller Entwicklungsstand und Zukunftsperspektive.

BACKGROUND: Digitalization in surgery is gaining attention in the surgical community, with robotics and augmented reality as key issues. ROBOTICS: The term surgical robot is basically not adequate to describe currently available telesupport and manipulation systems. These are passive tools which have to be activated by the surgeon and only provide relatively low levels of active support. Accordingly, justification of use is currently difficult with respect to the cost-benefit relationship. A real breakthrough will be achieved by upgrading them into genuine intelligent and collaborative support systems and justify the term as the true meaning of robotics. AUGMENTED REALITY (AR): Augmented or enriched reality improves or facilitates normal sensory perception by the integration of additional information of a different nature. Intuitive perception of the surgical site would have the potential to revolutionize surgery, but prior to clinical use, the matching of the real and the virtual world still has to be optimized (referencing); however, AR is now already a valuable tool for training and simulation as well as workflow support in the operating room (OR). CRITICAL COMMENT AND PERSPECTIVES: The promising new technological development towards the future cooperative surgical OR environment, including both robotic and AR modules, will have a significant impact on surgery, even in the mid-term. Decisive for this is that surgeons actively take part in the evaluation of this process to ensure that future "intelligent" tools will remain mere assistant or supporting systems.

Endoscopic rendez-vous reconstruction of complete biliary obstruction.

BACKGROUND AND STUDY AIMS: Complete biliary strictures normally require surgical intervention. We describe an alternative, minimally invasive endoscopic/percutaneous rendez-vous technique for the reconstruction of complete benign biliary strictures. PATIENTS AND METHODS: Complete biliary strictures were reconstructed in four patients using a rendez-vous percutaneous-endoscopic or percutaneous-percutaneous route guided by fluoroscopic and visual (transillumination) control. RESULTS: All four patients were treated successfully and safely with the rendez-vous technique. Complications were caused by the preliminary creation, dilatation and maturation of the percutaneous tract. CONCLUSION: This technique may offer a good alternative to surgical bilio-enteric anastomosis in experienced hands. The long term course of the patients treated remains to be seen.

[Surgical treatment of esophageal diverticula : Endoscopic or open approach?] / Operative Therapie von Divertikeln der Speiseröhre : Endoskopisch oder offen?

Esophageal diverticula are comparatively rare. The majority are Zenker's diverticula but parabronchial and epiphrenic diverticula can also occur. Parabronchial diverticula are of low clinical relevance, whereas Zenker's and epiphrenic diverticula both belong to the group of pulsion diverticula and can become clinically apparent by dysphagia and regurgitation. Approximately 100 years after the first surgical treatment, peroral approaches (e.g. stapler dissection and flexible endoscopic diverticulotomy) have now achieved a certain level of importance. Both approaches are less invasive than the open approach but are evidently more prone to recurrences. Accordingly, traditional open diverticulectomy with cervical myotomy should be recommended to patients with a reasonable life expectancy and an acceptable operative risk. This holds particularly true for Brombart stages I-III of the disease, as complete myotomy cannot be achieved via the peroral access. The classical surgical treatment of epiphrenic diverticula is open or laparoscopic/thoracoscopic diverticulectomy with distal myotomy, mostly combined with an anterior partial fundoplication; however, the leakage rate is high and several alternative options are currently being evaluated.

Esophageal bougination: a novel ex vivo endoscopic training model correlated with clinical data.

BACKGROUND: Esophageal bougination is a worldwide standard endoscopic procedure. Clinical methods and recommendations are based on clinical experiences only. Mechanical properties have never been described. Aim of the study was to establish a realistic ex vivo training model. Therefore, detailed assessment of relevant mechanical features of esophageal bougination should be evaluated ex vivo and in patient setting and correlated against. PATIENTS AND METHODS: A three-step concept was used to evaluate mechanical properties at stenosis level. First, insertion forces were evaluated in an ex vivo linear single stenosis model during steady mechanical insertion. Second, adding friction and properties of the pharynx and upper esophagus, the model was integrated in an artificial endoscopic training model (ELITE training model). Third, in vivo measurements were taken to correlate ex vivo data with parameters of a realistic patient setting. RESULTS: With the presented setup, we were able to assess insertion force and pressure levels in an artificial stricture using different sizes of commercially available standard bougies. In all models, there was a relevant increase in insertion force with higher stricture pressure levels. Insertion force levels in the ELITE model show higher levels compared to the linear stenosis model. Having regard to the maximum forces in patients, there is also a constant increase in mean insertion force according to higher bougie sizes, but lower forces were measured as in the ELITE model. DISCUSSION: The applied models are suitable to appraise mechanical properties of esophageal bougination in an ex vivo model and patient setting. Forces could be constituted reliable, significant increase was documented according to stenosis level and results were comparable to patient data. This was comparable to patient data. Further clinical evaluation in different kinds of stenosis is necessary.

[Comprehensive system integration and networking in operating rooms]. / Umfassende Systemintegration und Vernetzung im Operationssaal.

BACKGROUND: A comprehensive surveillance and control system integrating all devices and functions is a precondition for realization of the operating room of the future. STATE OF THE ART: Multiple proprietary integrated operation room systems are currently available with a central user interface; however, they only cover a relatively small part of all functionalities. INNOVATIVE APPROACHES: Internationally, there are at least three different initiatives to promote a comprehensive systems integration and networking in the operating room: the Japanese smart cyber operating theater (SCOT), the American medical device plug-and-play interoperability program (MDPnP) and the German secure and dynamic networking in operating room and hospital (OR.NET) project supported by the Federal Ministry of Education and Research. PRELIMINARY RESULTS: Within the framework of the internationally advanced OR.NET project, prototype solution approaches were realized, which make short-term and mid-term comprehensive data retrieval systems probable. An active and even autonomous control of the medical devices by the surveillance and control system (closed loop) is expected only in the long run due to strict regulatory barriers.

[Long-term HR-Manometry of the Esophagus: first findings in clinical use]. / Langzeit-HR-Manometrie der Speiseröhre: Erste Beobachtungen aus dem klinischen Einsatz.

Diagnosis of oesophageal motility disorders has been well established for many years now, although circadian gastrointestinal motility is still purely understood. So far, high-resolution manometry (HRM) is only available for short-term measurement in clinical practice to evaluate simultaneous pressure conditions throughout the esophagus. Thus, only a very limited period of time can be investigated. There is evidence that disorders in esophageal motility can cause severe discomfort and symptoms even though they only tend to occur spontaneously. When performing short-term-measurements, these often cannot be detected. Therefore, one can assume that long-term analysis of the esophageal function will provide valuable new insights, which will contribute to more effective medicamenteous and operative treatment in esophageal motility disorders. At our gastrointestinal functional diagnostic laboratory, it has been possible to perform high-resolution manometry over the period of 24 hours since June 2014. We used a manometric probe consisting of 36 pressure sensors which are connected to a mobile recording device for ambulatory measurement. This article describes our experiences in clinical use when performing long-term high-resolution manometry and discusses usability and relevance of the results in the context of the underlying esophageal motility disorder.

[Minimally invasive surgery and robotic surgery: surgery 4.0?]. / Minimalinvasive Chirurgie und "robotic surgery": Chirurgie 4.0?

Surgery can only maintain its role in a highly competitive environment if results are continuously improved, accompanied by further reduction of the interventional trauma for patients and with justifiable costs. Significant impulse to achieve this goal was expected from minimally invasive surgery and, in particular, robotic surgery; however, a real breakthrough has not yet been achieved. Accordingly, the new strategic approach of cognitive surgery is required to optimize the provision of surgical treatment. A full scale integration of all modules utilized in the operating room (OR) into a comprehensive network and the development of systems with technical cognition are needed to upgrade the current technical environment passively controlled by the surgeon into an active collaborative support system (surgery 4.0). Only then can the true potential of minimally invasive surgery and robotic surgery be exploited.

Comparative evaluation of HD 2D/3D laparoscopic monitors and benchmarking to a theoretically ideal 3D pseudodisplay: even well-experienced laparoscopists perform better with 3D.

BACKGROUND: Though theoretically superior to standard 2D visualization, 3D video systems have not yet achieved a breakthrough in laparoscopy. The latest 3D monitors, including autostereoscopic displays and high-definition (HD) resolution, are designed to overcome the existing limitations. METHODS: We performed a randomized study on 48 individuals with different experience levels in laparoscopy. Three different 3D displays (glasses-based 3D monitor, autostereoscopic display, and a mirror-based theoretically ideal 3D display) were compared to a 2D HD display by assessing multiple performance and mental workload parameters and rating the subjects during a laparoscopic suturing task. Electromagnetic tracking provided information on the instruments' pathlength, movement velocity, and economy. The usability, the perception of visual discomfort, and the quality of image transmission of each monitor were subjectively rated. RESULTS: Almost all performance parameters were superior with the conventional glasses-based 3D display compared to the 2D display and the autostereoscopic display, but were often significantly exceeded by the mirror-based 3D display. Subjects performed a task faster and with greater precision when visualization was achieved with the 3D and the mirror-based display. Instrument pathlength was shortened by improved depth perception. Workload parameters (NASA TLX) did not show significant differences. Test persons complained of impaired vision while using the autostereoscopic monitor. The 3D and 2D displays were rated user-friendly and applicable in daily work. Experienced and inexperienced laparoscopists profited equally from using a 3D display, with an improvement in task performance about 20%. CONCLUSION: Novel 3D displays improve laparoscopic interventions as a result of faster performance and higher precision without causing a higher mental workload. Therefore, they have the potential to significantly impact the further development of minimally invasive surgery. However, as shown by the custom-built 3D mirror display, this effect can be improved, thus stimulating further research.

[Further technical and digital development in minimally invasive and conventional surgery]. / Technische und digitale Weiterentwicklung in der laparoskopischen/offenen Chirurgie.

Technological innovations have initiated a fundamental change in invasive therapeutic approaches which has led to a welcome reduction of surgical trauma but was also associated with a declining role of conventional surgery. Active utilization of future technological developments is decisive to promote new therapeutic strategies and to avoid a further loss of importance of surgery. This includes individualized preoperative therapy planning as well as intraoperative diagnostic work-up and navigation and the use of new functional intelligent implants. The working environment "surgical operating room" has to be refurbished into an integrated cooperating functional system. The impact of new technological developments is particularly obvious in minimally invasive surgery. There is a clear tendency towards further reduction in trauma in the surgical access. The incision will become smaller and the number of ports will be further reduced, with the aim of ultimately having just one port (monoport surgery) or even via natural access routes (scarless surgery). Among others, improved visualization including, e.g. autostereoscopy, digital image processing and intelligent support systems, which are able to assist in a cooperative way, will enable these goals to be achieved.