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.

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.

[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.

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.

[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.

[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.

[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.

[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.

Preexamination prediction of radiographic findings.

Computerized medical logic has been developed to calculate the patient-specific pretest likelihood of pleural fluid for radiographic examinations. This medical logic was determined by searching the computerized data base for clinical indicants which are found to differ between groups of patients with and without pleural fluid. By using a priori probabilities of pleural fluid and sequential application of Bayes' equation to revise the likelihood according to the presence of significant indicants, patient-specific likelihood were calculated. This medical logic was tested on a group of 591 patients with and without pleural fluid by radiographic evidence. The results indicated a sensitivity of 95% and a specificity of 81%.

Medical impact analysis for the space station.

Since the Space Station Health Maintenance Facility can house only a relatively limited quantity of supplies and equipment, the decisions about what should be included must be based on documented research. In this study, Space Station medical care priorities were determined by a medical impact analysis of two analog populations, U.S. Army and U.S. Navy personnel. Diseases and injuries in the International Classification of Disease, 9th Revision, Clinical Modification (ICD-9-CM) were ranked, using a Medical Impact Score (MIS) combining modified incidence rate and a function of disease outcome. The validity of the analysis method was tested by measuring rank order correlation between the two analog populations. Despite virtually identical age and sex distributions, Army and Navy incidence rates differed significantly for half of the ICD-9-CM categories, p less than 0.05. Disability rates differed for 76%, p less than 0.05. Nevertheless, Army and Navy MIS rank orders for categories and sections were not significantly different, p less than 0.001. In critical ways, the Space Station will be a safer environment than Earth. Cardiac events, musculoskeletal injuries, affective psychoses, and renal calculi were among the highest scoring categories.

A computer system for analysis and transmission of spirometry waveforms using volume sampling.

A microprocessor-controlled data gathering system for telemetry and analysis of spirometry waveforms was implemented using a completely digital design. Spirometry waveforms were obtained from an optical shaft encoder attached to a rolling seal spirometer. Time intervals between 10-ml volume changes (volume sampling) were stored. The digital design eliminated problems of analog signal sampling. The system measured flows up to 12 liters/sec with 5% accuracy and volumes up to 10 liters with 1% accuracy. Transmission of 10 waveforms took about 3 min. Error detection assured that no data were lost or distorted during transmission. A pulmonary physician at the central hospital reviewed the volume-time and flow-volume waveforms and interpretations generated by the central computer before forwarding the results and consulting with the rural physician. This system is suitable for use in a major hospital, rural hospital, or small clinic because of the system's simplicity and small size.

The role of smart medical systems in the Space Station.

NASA is developing a Health Maintenance Facility to provide medical equipment and supplies requisite for the Space Station to be launched in the late 1990s. An essential component of this medical facility is a computerized Medical Decision Support System which will expedite medical officers' efforts to maintain the crew's health. The computerized system includes four major functions: 1. A data collection and storage system with a self-contained medical expert scheme for performing treatment protocols. The expert system has 'data driven' and 'time driven' capabilities to facilitate automatic decision-making functions. 2. An integrated medical record and medical 'reference' information management component. 3. An inventory management system for medical supplies and pharmaceuticals. 4. Video, audio, and data communications between the medical officer in the Space Station and ground-based medical personnel. This paper discusses the design of such computerized data collection, communications and expert medical systems as will be developed for use in a Space Station Health Maintenance Facility.

Molecular mechanism of diltiazem interaction with L-type Ca2+ channels.

Benzothiazepine Ca2+ antagonists (such as (+)-cis-diltiazem) interact with transmembrane segments IIIS6 and IVS6 in the alpha1 subunit of L-type Ca2+ channels. We investigated the contribution of individual IIIS6 amino acid residues for diltiazem sensitivity by employing alanine scanning mutagenesis in a benzothiazepine-sensitive alpha1 subunit chimera (ALDIL) expressed in Xenopus laevis oocytes. The most dramatic decrease of block by 100 microM diltiazem (ALDIL 45 +/- 4.8% inhibition) during trains of 100-ms pulses (0.1 Hz, -80 mV holding potential) was found after mutation of adjacent IIIS6 residues Phe1164(21 +/- 3%) and Val1165 (8.5 +/- 1.4%). Diltiazem delayed current recovery by promoting a slowly recovering current component. This effect was similar in ALDIL and F1164A but largely prevented in V1165A. Both mutations slowed inactivation kinetics during a pulse. The reduced diltiazem block can therefore be explained by slowing of inactivation kinetics (F1164A and V1165A) and accelerated recovery from drug block (V1165A). The bulkier diltiazem derivative benziazem still efficiently blocked V1165A. From these functional and from additional radioligand binding studies with the dihydropyridine (+)-[3H]isradipine we propose a model in which Val1165 controls dissociation of the bound diltiazem molecule, and where bulky substituents on the basic nitrogen of diltiazem protrude toward the adjacent dihydropyridine binding domain.