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The healing of gastrointestinal anastomoses is a complex biological process influenced by numerous factors. Various strategies to support healing and prevent anastomotic leakage (AL) exist, encompassing preoperative, intraoperative and postoperative measures. Preoperative interventions aim to optimize the patient and the tissue environment, particularly the gut microbiome. Intraoperative measures are technical in nature and include the choice of surgical access, the anastomotic technique and anastomotic reinforcement. Various procedures of the intraoperative diagnostics enable identification of such anastomoses requiring additional protective measures. Recently, indocyanine green (ICG) fluoroscopy has become established for evaluation of tissue perfusion, while newer techniques such as spectral microscopy offer promising possibilities. Postoperative diagnostic methods aim to identify potential AL as early as possible to enable initiation of therapeutic steps even before the onset of symptoms. These procedures range from various imaging techniques to innovative bioresorbable, pH-sensitive implants for early AL detection. Due to the multifactorial genesis of AL and the diverse technical possibilities, no single method will become established for prevention of AL. Instead, a combination of measures will ultimately lead to optimal anastomotic healing. The use of artificial intelligence and analyses based on the data promises a better interpretation of the vast amount of data and therefore to be able to provide general recommendations., (© 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Purpose: Dysphagia is the inability or difficulty to swallow normally. Standard procedures for diagnosing the exact disease are, among others, X-ray videofluoroscopy, manometry and impedance examinations, usually performed consecutively. In order to gain more insights, ongoing research is aiming to collect these different modalities at the same time, with the goal to present them in a joint visualization. One idea to create a combined view is the projection of the manometry and impedance values onto the right location in the X-ray images. This requires to identify the exact sensor locations in the images., Methods: This work gives an overview of the challenges associated with the sensor detection task and proposes a robust approach to detect the sensors in X-ray image sequences, ultimately allowing to project the manometry and impedance values onto the right location in the images., Results: The developed sensor detection approach is evaluated on a total of 14 sequences from different patients, achieving a F1-score of 86.36%. To demonstrate the robustness of the approach, another study is performed by adding different levels of noise to the images, with the performance of our sensor detection method only slightly decreasing in these scenarios. This robust sensor detection provides the basis to accurately project manometry and impedance values onto the images, allowing to create a multimodal visualization of the swallow process. The resulting visualizations are evaluated qualitatively by domain experts, indicating a great benefit of this proposed fused visualization approach., Conclusion: Using our preprocessing and sensor detection method, we show that the sensor detection task can be successfully approached with high accuracy. This allows to create a novel, multimodal visualization of esophageal motility, helping to provide more insights into swallow disorders of patients., (© 2024. The Author(s).)

Purpose: Video-based intra-abdominal instrument tracking for laparoscopic surgeries is a common research area. However, the tracking can only be done with instruments that are actually visible in the laparoscopic image. By using extra-abdominal cameras to detect trocars and classify their occupancy state, additional information about the instrument location, whether an instrument is still in the abdomen or not, can be obtained. This can enhance laparoscopic workflow understanding and enrich already existing intra-abdominal solutions., Methods: A data set of four laparoscopic surgeries recorded with two time-synchronized extra-abdominal 2D cameras was generated. The preprocessed and annotated data were used to train a deep learning-based network architecture consisting of a trocar detection, a centroid tracker and a temporal model to provide the occupancy state of all trocars during the surgery., Results: The trocar detection model achieves an F1 score of 95.06 ± 0.88 % . The prediction of the occupancy state yields an F1 score of 89.29 ± 5.29 % , providing a first step towards enhanced surgical workflow understanding., Conclusion: The current method shows promising results for the extra-abdominal tracking of trocars and their occupancy state. Future advancements include the enlargement of the data set and incorporation of intra-abdominal imaging to facilitate accurate assignment of instruments to trocars., (© 2024. The Author(s).)

Purpose: Decision support systems and context-aware assistance in the operating room have emerged as the key clinical applications supporting surgeons in their daily work and are generally based on single modalities. The model- and knowledge-based integration of multimodal data as a basis for decision support systems that can dynamically adapt to the surgical workflow has not yet been established. Therefore, we propose a knowledge-enhanced method for fusing multimodal data for anticipation tasks., Methods: We developed a holistic, multimodal graph-based approach combining imaging and non-imaging information in a knowledge graph representing the intraoperative scene of a surgery. Node and edge features of the knowledge graph are extracted from suitable data sources in the operating room using machine learning. A spatiotemporal graph neural network architecture subsequently allows for interpretation of relational and temporal patterns within the knowledge graph. We apply our approach to the downstream task of instrument anticipation while presenting a suitable modeling and evaluation strategy for this task., Results: Our approach achieves an F1 score of 66.86% in terms of instrument anticipation, allowing for a seamless surgical workflow and adding a valuable impact for surgical decision support systems. A resting recall of 63.33% indicates the non-prematurity of the anticipations., Conclusion: This work shows how multimodal data can be combined with the topological properties of an operating room in a graph-based approach. Our multimodal graph architecture serves as a basis for context-sensitive decision support systems in laparoscopic surgery considering a comprehensive intraoperative operating scene., (© 2024. The Author(s).)

Purpose: Healthcare systems around the world are increasingly facing severe challenges due to problems such as staff shortage, changing demographics and the reliance on an often strongly human-dependent environment. One approach aiming to address these issues is the development of new telemedicine applications. The currently researched network standard 6G promises to deliver many new features which could be beneficial to leverage the full potential of emerging telemedical solutions and overcome the limitations of current network standards., Methods: We developed a telerobotic examination system with a distributed robot control infrastructure to investigate the benefits and challenges of distributed computing scenarios, such as fog computing, in medical applications. We investigate different software configurations for which we characterize the network traffic and computational loads and subsequently establish network allocation strategies for different types of modular application functions (MAFs)., Results: The results indicate a high variability in the usage profiles of these MAFs, both in terms of computational load and networking behavior, which in turn allows the development of allocation strategies for different types of MAFs according to their requirements. Furthermore, the results provide a strong basis for further exploration of distributed computing scenarios in medical robotics., Conclusion: This work lays the foundation for the development of medical robotic applications using 6G network architectures and distributed computing scenarios, such as fog computing. In the future, we plan to investigate the capability to dynamically shift MAFs within the network based on current situational demand, which could help to further optimize the performance of network-based medical applications and play a role in addressing the increasingly critical challenges in healthcare., (© 2024. The Author(s).)

Background: Anastomotic leakage following colorectal surgery remains a significant complication despite advances in surgical techniques. Recent findings on serosal injury repair in coelomic cavities, such as the peritoneum, challenge the current understanding of the cellular origins and mechanisms underlying intestinal anastomotic healing. Understanding the contribution of each layer of the intestinal wall during anastomotic healing is needed to find new therapeutic strategies to prevent anastomotic leakage. The aim of this experimental study was to investigate the role of the serosal layer of the intestinal wall in anastomotic healing., Materials and Methods: Comprehensive histologic analysis of human and murine anastomoses was performed to elucidate histologic changes in the different intestinal layers during anastomotic healing. In vivo staining of the extracellular matrix (ECM) in the serosal layer was performed using a fluorophore-conjugated N-hydroxysuccinimide-ester before anastomosis surgery in a murine model., Results: Histological examination of both human and murine anastomoses revealed that closure of the serosal layer occurred first during the healing process. In vivo serosal ECM staining demonstrated that a significant portion of the newly formed ECM within the anastomosis was indeed deposited onto the serosal layer. Furthermore, mesenchymal cells within the anastomotic scar were positive for mesothelial cell markers, podoplanin and Wilms tumour protein., Conclusions: In this experimental study, the results suggest that serosal scar formation is an important mechanism for anastomotic integrity in intestinal anastomoses. Mesothelial cells may significantly contribute to scar formation during anastomotic healing through epithelial-to-mesenchymal transition, potentially suggesting a novel therapeutic target to prevent anastomotic leakage by enhancing physiological healing processes., (© The Author(s) 2024. Published by Oxford University Press on behalf of BJS Foundation Ltd.)

Introduction: In robotic-assisted surgery (RAS), the input device is the primary site for the flow of information between the user and the robot. Most RAS systems remove the surgeon's console from the sterile surgical site. Beneficial for performing lengthy procedures with complex systems, this ultimately lacks the flexibility that comes with the surgeon being able to remain at the sterile site., Methods: A prototype of an input device for RAS is constructed. The focus lies on intuitive control for surgeons and a seamless integration into the surgical workflow within the sterile environment. The kinematic design is translated from the kinematics of laparoscopic surgery. The input device uses three degrees of freedom from a flexible instrument as input. The prototype's performance is compared to that of a commercially available device in an evaluation. Metrics are used to evaluate the surgeons' performance with the respective input device in a virtual environment implemented for the evaluation., Results: The evaluation of the two input devices shows statistically significant differences in the performance metrics. With the proposed prototype, the surgeons perform the tasks faster, more precisely, and with fewer errors., Conclusion: The prototype is an efficient and intuitive input device for surgeons with laparoscopic experience. The placement in the sterile working area allows for seamless integration into the surgical workflow and can potentially enable new robotic approaches., (© 2024. The Author(s).)

Background: Machine learning and robotics technologies are increasingly being used in the healthcare domain to improve the quality and efficiency of surgeries and to address challenges such as staff shortages. Robotic scrub nurses in particular offer great potential to address staff shortages by assuming nursing tasks such as the handover of surgical instruments., Methods: We introduce a robotic scrub nurse system designed to enhance the quality of surgeries and efficiency of surgical workflows by predicting and delivering the required surgical instruments based on real-time laparoscopic video analysis. We propose a three-stage deep learning architecture consisting of a single frame-, temporal multi frame-, and informed model to anticipate surgical instruments. The anticipation model was trained on a total of 62 laparoscopic cholecystectomies., Results: Here, we show that our prediction system can accurately anticipate 71.54% of the surgical instruments required during laparoscopic cholecystectomies in advance, facilitating a smoother surgical workflow and reducing the need for verbal communication. As the instruments in the left working trocar are changed less frequently and according to a standardized procedure, the prediction system works particularly well for this trocar., Conclusions: The robotic scrub nurse thus acts as a mind reader and helps to mitigate staff shortages by taking over a great share of the workload during surgeries while additionally enabling an enhanced process standardization., (© 2024. The Author(s).)

Introduction: Surgical documentation has many implications. However, its primary function is to transfer information about surgical procedures to other medical professionals. Thereby, written reports describing procedures in detail are the current standard, impeding comprehensive understanding of patient-individual life-spanning surgical course, especially if surgeries are performed at a timely distance and in diverse facilities. Therefore, we developed a novel model-based approach for documentation of visceral surgeries, denoted as 'Surgical Documentation Markup-Modeling' (SDM-M)., Material and Methods: For scientific evaluation, we developed a web-based prototype software allowing for creating hierarchical anatomical models that can be modified by individual surgery-related markup information. Thus, a patient's cumulated 'surgical load' can be displayed on a timeline deploying interactive anatomical 3D models. To evaluate the possible impact on daily clinical routine, we performed an evaluation study with 24 surgeons and advanced medical students, elaborating on simulated complex surgical cases, once with classic written reports and once with our prototypical SDM-M software., Results: Leveraging SDM-M in an experimental environment reduced the time needed for elaborating simulated complex surgical cases from 354 ± 85 s with the classic approach to 277 ± 128 s. (p = 0.00109) The perceived task load measured by the Raw NASA-TLX was reduced significantly (p = 0.00003) with decreased mental (p = 0.00004) and physical (p = 0.01403) demand. Also, time demand (p = 0.00041), performance (p = 0.00161), effort (p = 0.00024), and frustration (p = 0.00031) were improved significantly., Discussion: Model-based approaches for life-spanning surgical documentation could improve the daily clinical elaboration and understanding of complex cases in visceral surgery. Besides reduced workload and time sparing, even a more structured assessment of individual surgical cases could foster improved planning of further surgeries, information transfer, and even scientific evaluation, considering the cumulative 'surgical load.', Conclusion: Life-spanning model-based documentation of visceral surgical cases could significantly improve surgery and workload., (© 2024. The Author(s).)

Purpose: Even though workflow analysis in the operating room has come a long way, current systems are still limited to research. In the quest for a robust, universal setup, hardly any attention has been given to the dimension of audio despite its numerous advantages, such as low costs, location, and sight independence, or little required processing power., Methodology: We present an approach for audio-based event detection that solely relies on two microphones capturing the sound in the operating room. Therefore, a new data set was created with over 63 h of audio recorded and annotated at the University Hospital rechts der Isar. Sound files were labeled, preprocessed, augmented, and subsequently converted to log-mel-spectrograms that served as a visual input for an event classification using pretrained convolutional neural networks., Results: Comparing multiple architectures, we were able to show that even lightweight models, such as MobileNet, can already provide promising results. Data augmentation additionally improved the classification of 11 defined classes, including inter alia different types of coagulation, operating table movements as well as an idle class. With the newly created audio data set, an overall accuracy of 90%, a precision of 91% and a F1-score of 91% were achieved, demonstrating the feasibility of an audio-based event recognition in the operating room., Conclusion: With this first proof of concept, we demonstrated that audio events can serve as a meaningful source of information that goes beyond spoken language and can easily be integrated into future workflow recognition pipelines using computational inexpensive architectures., (© 2024. The Author(s).)

Purpose: Acoustic information can contain viable information in medicine and specifically in surgery. While laparoscopy depends mainly on visual information, our goal is to develop the means to capture and process acoustic information during laparoscopic surgery., Methods: To achieve this, we iteratively developed three prototypes that will overcome the abdominal wall as a sound barrier and can be used with standard trocars. We evaluated them in terms of clinical applicability and sound transmission quality. Furthermore, the applicability of each prototype for sound classification based on machine learning was evaluated., Results: Our developed prototypes for recording airborne sound from the intraperitoneal cavity represent a promising solution suitable for real-world clinical usage All three prototypes fulfill our set requirements in terms of clinical applicability (i.e., air-tightness, invasiveness, sterility) and show promising results regarding their acoustic characteristics and the associated results on ML-based sound classification., Conclusion: In summary, our prototypes for capturing acoustic information during laparoscopic surgeries integrate seamlessly with existing procedures and have the potential to augment the surgeon's perception. This advancement could change how surgeons interact with and understand the surgical field., (© 2024. The Author(s).)

Prevention of intestinal fibrosis remains an unresolved problem in the treatment of Crohn's disease (CD), as specific antifibrotic therapies are not yet available. Appropriate analysis of fibrosis severity is essential for assessing the therapeutic efficacy of potential antifibrotic drugs. The aim of this study was to develop an observer-independent method to quantify intestinal fibrosis in surgical specimens from patients with CD using structural analysis of the extracellular matrix (ECM). We performed fractal analysis in fibrotic and control histological sections of patients with surgery for CD (n = 28). To specifically assess the structure of the collagen matrix, polarized light microscopy was used. A score to quantify collagen fiber alignment and the color of the polarized light was established. Fractal dimension as a measure for the structural complexity correlated significantly with the histological fibrosis score whereas lacunarity as a measure for the compactness of the ECM showed a negative correlation. Polarized light microscopy to visualize the collagen network underlined the structural changes in the ECM network in advanced fibrosis. In conclusion, observer-independent quantification of the structural complexity of the ECM by fractal analysis is a suitable method to quantify the degree of intestinal fibrosis in histological samples from patients with CD., (© 2024. The Author(s).)

Purpose: Sigmoid diverticulitis is a disease with a high socioeconomic burden, accounting for a high number of left-sided colonic resections worldwide. Modern surgical scheduling relies on accurate prediction of operation times to enhance patient care and optimize healthcare resources. This study aims to develop a predictive model for surgery duration in laparoscopic sigmoid resections, based on preoperative CT biometric and demographic patient data., Methods: This retrospective single-center cohort study included 85 patients who underwent laparoscopic sigmoid resection for diverticular disease. Potentially relevant procedure-specific anatomical parameters recommended by a surgical expert were measured in preoperative CT imaging. After random split into training and test set (75% / 25%) multiclass logistic regression was performed and a Random Forest classifier was trained on CT imaging parameters, patient age, and sex in the training cohort to predict categorized surgery duration. The models were evaluated in the test cohort using established performance metrics including receiver operating characteristics area under the curve (AUROC)., Results: The Random Forest model achieved a good average AUROC of 0.78. It allowed a very good prediction of long (AUROC = 0.89; specificity 0.71; sensitivity 1.0) and short (AUROC = 0.81; specificity 0.77; sensitivity 0.56) procedures. It clearly outperformed the multiclass logistic regression model (AUROC: average = 0.33; short = 0.31; long = 0.22)., Conclusion: A Random Forest classifier trained on demographic and CT imaging biometric patient data could predict procedure duration outliers of laparoscopic sigmoid resections. Pending validation in a multicenter study, this approach could potentially improve procedure scheduling in visceral surgery and be scaled to other procedures., (© 2024. The Author(s).)

Introduction: The SARS-CoV-2 pandemic has affected global public healthcare for several years. Numerous medical professionals have been infected since the outbreak in 2019, resulting in a shortage of healthcare providers. Since traditional personal protective wear was insufficient to eliminate the virus transmission reliably, new strategies to avoid cross-infection were imperative while enabling high-quality medical care. In the project ProteCT, we investigated the potential of robotic-assisted examination in providing medical examination via a telemedical approach., Material and Methods: We constructed a fully functional examination cabin equipped with cameras, microphones, screens and robotic arms to evaluate usability and perception. Therefore, we conducted a preliminary study with 10 healthy volunteers and 10 physicians to gain first insights and optimize the setup. In a second step, we performed telemedical examinations of actual patients from the local emergency department to compare the robotic approach with the classical method of measuring vital signs, auscultation, palpation and percussion., Results: The preliminary study identified basic requirements, such as the need for force-feedback and telemedical training for physicians. In the main study, acceptance was high and most patients indicated they would use a telemedical system again. Our setup enabled the physician to make the same diagnoses as by classic examination in the emergency department in most cases., Discussion: The potential acceptance of a telemedical system such as ProteCT is high. Robotic telemedical approaches could complement future healthcare beyond the Corona pandemic to reach rural areas or even war zones. Moreover, the daily clinical use of robotic telemedicine could improve patients' safety, the quality of perioperative management and the workflow in any medical facility., Conclusion: The development of telemedical and telerobotic systems is a multidisciplinary and complex challenge. However, acceptance of the proposed system was high among patients and physicians, indicating the potential use of similar systems for future healthcare., Competing Interests: The authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: SH is a shareholder in Franka Emika GmbH (Munich, Germany) but declares no non-financial competing interests., (© The Author(s) 2024.)

The COVID-19 outbreak has triggered a global health and economic crisis, necessitating widespread testing to control viral spread amidst rising cases and fatalities. The recommended testing method, a combined naso- and oropharyngeal swab, poses risks and demands limited protective gear. In response to the COVID-19 pandemic, we developed and tested the first autonomous swab robot station for Naso- and Oropharyngeal Coronavirus Screening (SR-NOCS). A force-sensitive robot running under a Cartesian impedance controller is employed to drive the swab to the sampling area. This groundbreaking device underwent two clinical studies-one conducted during the initial pandemic lockdown in Europe (early 2021) and the other, more recently, in a public place after the pandemic had subsided earlier in the year 2023. In total, 52 patients suspected of COVID-19 infection were included in these clinical studies. The results revealed a complete positive correlation between autonomous and manual sampling. The test subjects exhibited a high acceptance rate, all expressing a willingness to undergo future tests with SR-NOCS. Based on our findings, such systems could enhance testing capabilities, potentially conducting up to 300 tests per robot per day with consistent precision. The tests can be carried out with minimal supervision, reducing infection risks and effectively safeguarding patients and healthcare workers., (© 2024. The Author(s).)

Despite its versatile applicability the intraoperative use of a mobile C‑arm is often problematic and potentially associated with increased radiation exposure for both the patient and the personnel. In particular, the correct positioning for adequate imaging can become a problem as the nonsterile circulating nurse has to coordinate the various maneuvers together with the surgeon without having a good view of the surgical field. The sluggishness of the equipment and the intraoperative setting (sterile borders, additional hardware, etc.) pose further challenges. A light detection and ranging (LIDAR)-based assistance system shows promise to provide accurate and intuitive repositioning support as part of an initial series of experimental trials. For this purpose, the sensors are attached to the C‑arm base unit and enable navigation of the device in the operating room to a stored target position using a simultaneous localization and mapping (SLAM) algorithm. An improvement of the workflow as well as a reduction of radiation exposure represent the possible potential of this system. The advantages over other experimental approaches are the lack of external hardware and the ease of use without isolating the operator from the rest of the operating room environment; however, the suitability for daily use in the presence of additional interfering factors should be verified in further studies., (© 2023. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Purpose: Integrating robotic scrub nurses in the operating room has the potential to help overcome staff shortages and limited use of available operating capacities in hospitals. Existing approaches of robotic scrub nurses are mainly focused on open surgical procedures, neglecting laparoscopic procedures. Laparoscopic interventions offer great potential for the context-sensitive integration of robotic systems due to possible standardization. However, the first step is to ensure the safe manipulation of laparoscopic instruments., Methods: A robotic platform with a universal gripper system was designed to pick up and place laparoscopic as well as da Vinci[Formula: see text] instruments in an efficient workflow. The robustness of the gripper system was studied using a test protocol, which included a force absorption test to determine the operational safety limits of the design and a grip test to determine the system performance., Results: The test protocol shows results regarding force and torque absorption capabilities of the end effector, which are essential when transferring an instrument to the surgeon to enable a robust handover. The grip tests show that the laparoscopic instruments can be safely picked up, manipulated and returned independent of unexpected positional deviations. The gripper system also enables the manipulation of da Vinci[Formula: see text] instruments, opening the door for robot-robot interaction., Conclusion: Our evaluation tests have shown that our robotic scrub nurse with the universal gripper system can safely and robustly manipulate laparoscopic and da Vinci[Formula: see text] instruments. The system design will continue with the integration of context-sensitive capabilities., (© 2023. The Author(s).)

Background and Aims: High-dose glucocorticoid treatment has been identified as a risk factor for anastomotic leakage in patients with inflammatory bowel disease [IBD] undergoing bowel resection surgery. By contrast, active disease during surgery is also associated with elevated morbidity. Perioperative low-dose treatment might be beneficial regarding postoperative outcomes by controlling disease activity. The present study is the first to investigate the dose-dependent effect of perioperative prednisolone therapy in a murine IBD model combining dextran sodium sulphate [DSS] colitis with intestinal anastomosis surgery., Methods: In 84 10-week-old wild-type mice, a colorectal anastomosis was performed using a microsurgical technique. Half the animals received induction of chemical colitis with 2% DSS via drinking water prior to surgery. In both groups, one-third of the animals received daily oral administration of high-dose [0.533 mg/kg] and one-third low-dose [0.133 mg/kg] prednisolone. Evaluation was performed on postoperative days 3 and 7., Results: While high-dose prednisolone treatment led to an increased anastomotic leakage rate in mice under colitis, low-dose prednisolone treatment limited preoperative disease activity and did not influence the leakage rate. Histological examination showed a beneficial effect of low-dose prednisolone treatment on microscopic abscess formation at the anastomotic site in DSS mice as well as an increased anastomotic healing score., Conclusions: We demonstrate a beneficial effect of perioperative short-term low-dose prednisolone treatment on intestinal anastomotic healing in the context of colitis. Perioperative use of short-term low-dose prednisolone treatment might be beneficial in IBD patients who need to undergo surgery during active disease., (© The Author(s) 2023. Published by Oxford University Press on behalf of European Crohn’s and Colitis Organisation. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Background: Endoscopic treatment of Zenker's diverticulum is an attractive minimally invasive alternative compared to the classic open approach. However, increased recurrence rate were reported. In case of relapse, endoscopic therapy might be repeated, or alternatively open surgery is performed. This study aimed to identify potential differences in the outcomes between primary or secondary surgical treatment in Zenker's diverticulum., Methods: From January 2003 to April 2019, 227 subsequent patients underwent surgical diverticulectomy and cervical myotomy at the surgical department of TUM. 41 of 227 patients had received previous therapy, either open or endoscopic. Perioperative parameters in priorly untreated patients were retrospectively compared to those after previous therapy (mostly endoscopic) with special regard to perioperative data and postoperative complications. Univariate and multivariate regression analyses were performed to identify predictors for postoperative complications., Results: We could show that the number of complications (p = 0.047) in pretreated patients is significant higher as well as the severity after Clavien-Dindo (p = 0.025). Stapler line leakage, wound infections, and operative revision rate was higher also pretreated group. Pretreatment and surgery time showed a significant association with postoperative complications in univariate analysis. In multivariate analysis, pretreatment remained a significant independent predictor of complications., Conclusion: The present data indicate that endoscopic therapy might represent a risk factor for postoperative complications in case of relapse surgery. Therefore primary open surgery should be debated in patients with an increased high risk of relapse., (© 2022. The Author(s).)

Purpose: There are only rough estimates of the worldwide incidence of pilonidal sinus carcinoma. The purpose of the study is to explore the demographic characteristics of this disease and to provide more precise information about its incidence., Methods: The study included questioning the surgeons and pathologists in Germany in addition to a literature research. The literature investigation included all published articles about pilonidal carcinoma in all languages. The questionnaire included 1050 pathologists and all 834 hospitals with a surgical division in Germany. The outcome measures included the total number of cases, the language of publication, gender, age, country of origin, interval until the diagnosis of carcinoma, and reported incidence based on local studies., Results: From 1900 to 2022, we found 140 cases of pilonidal sinus carcinoma in 103 articles. The investigation revealed two additional unpublished cases from Germany. The male-to-female ratio was 7.75:1. The countries with the most cases were the USA (35 cases, 25.0%), Spain (13 cases, 9.3%), and Turkey (11 cases, 7.6%). The average age was 54.0 ± 11.8 years and the interval between the diagnosis of the disease and the development of carcinoma was 20.1 ± 14.1 years. There was a parallel increase in reported cases of pilonidal sinus disease and pilonidal carcinoma over the last century. The reported incidence varied from 0.03% to 5.56%. The worldwide calculated incidence equaled 0.17%., Conclusion: Due to underreporting and other causes, the incidence of carcinoma emerging on the background of pilonidal sinus disease is higher than reported., (© 2023. The Author(s).)

Purpose: Overageing and climate change cause a need for making processes in the operating room wing (OR wing) more efficient. While many promising technologies are available today, traditional OR wings are not designed for seamlessly integrating these aids. To overcome this discrepancy, we present and motivate multiple ideas on how to transform current architectural design strategies., Methods: The presented concepts originate from expert discussions and studies of the available literature, but also from experiences made in the course of daily care delivery. Additionally, a comprehensive evaluation of current and historic OR theatre designs and the problems which are encountered herein has been conducted., Results: We present three innovative concepts regarding the restructuring of traditional OR wing layouts. To achieve better process optimization, hygiene, and energy efficiency, we propose to divide the OR wing into separate "patient", "procedure" and "staff" zones. For better flexibility regarding perioperative needs and technology integration, we propose to use a hexagon shape combined with reconfigurable walls for designing operating rooms., Conclusion: The concepts presented herein provide a solid foundation for further considerations regarding perioperative process optimization and seamless integration of technology into modern OR wing facilities. We aim at expanding on these results to develop a comprehensive vision for the OR wing of the future., (© 2022. The Author(s).)

Purpose: Integrating fleets of mobile service robots into the operating room wing (OR wing) has the potential to help overcome staff shortages and reduce the amount of dull or unhealthy tasks for humans. However, the OR wing has been little studied in this regard and the requirements for realizing this vision have not yet been fully identified. This includes fundamental aspects such as fleet size and composition, which we have now studied comprehensively for the first time., Methods: Using simulation, 150 different scenarios with varying fleet compositions, robot speeds and workloads were studied for a setup based on a real-life OR wing. The simulation included battery recharging cycles and queueing due to shared resources., Results: For all simulated scenarios we report results regarding total duration of execution, average task response times and fleet utilization. The relationship between these performance measures and global scenario parameters-such as fleet size, fleet composition, robot velocity and the number of operating rooms to be served-is visualized., Conclusion: Our simulation-based studies have proven to be a valuable tool for individualized dimensioning of mobile robotic fleets, based on realistic workflows and environmental models. Thereby, important implications for future developments of mobile robots have been identified and a basis of decision-making regarding fleet size, fleet composition, robot capabilities and robot velocities can be provided. Due to costs, space limitations and safety requirements, these aspects must be carefully considered to successfully integrate mobile robotic technology into real-world OR wing environments., (© 2022. The Author(s).)

Aim: Anastomotic leakage (AL) is one of the most dreaded complications in colorectal surgery. In 2013, the International Classification of Diseases code K91.83 for AL was introduced in Germany, allowing nationwide analysis of AL rates and associated parameters. The aim of this population-based study was to investigate the current incidence, risk factors, mortality, clinical management, and associated costs of AL in colorectal surgery., Methods: A data query was performed based on diagnosis-related group data of all hospital cases of inpatients undergoing colon or sphincter-preserving rectal resections between 2013 and 2018 in Germany., Results: A total number of 690,690 inpatient cases were included in this study. AL rates were 6.7% for colon resections and 9.2% for rectal resections in 2018. Regarding the treatment of AL, the application of endoluminal vacuum therapy increased during the studied period, while rates of relaparotomy, abdominal vacuum therapy, and terminal enterostomy remained stable. AL was associated with significantly increased in-house mortality (7.11% vs. 20.11% for colon resections and 3.52% vs. 11.33% for rectal resections in 2018) and higher socioeconomic costs (mean hospital reimbursement volume per case: 14,877€ (no AL) vs. 37,521€ (AL) for colon resections and 14,602€ (no AL) vs. 30,606€ (AL) for rectal resections in 2018)., Conclusions: During the studied time period, AL rates did not decrease, and associated mortality remained at a high level. Our study provides updated population-based data on the clinical and economic burden of AL in Germany. Focused research in the field of AL is still urgently necessary to develop targeted strategies to prevent AL, improve patient care, and decrease socioeconomic costs., (© 2023. The Author(s).)

The identification and characterization of signal regions in Nuclear Magnetic Resonance (NMR) spectra is a challenging but crucial phase in the analysis and determination of complex chemical compounds. Here, we present a novel supervised deep learning approach to perform automatic detection and classification of multiplets in 1 H NMR spectra. Our deep neural network was trained on a large number of synthetic spectra, with complete control over the features represented in the samples. We show that our model can detect signal regions effectively and minimize classification errors between different types of resonance patterns. We demonstrate that the network generalizes remarkably well on real experimental 1 H NMR spectra., Competing Interests: SB is employed by Bruker Schweiz AG. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Fischetti, Schmid, Bruderer, Caldarelli, Scarso, Henrici and Wilhelm.)

Importance: Differentiating between malignant and benign etiology in large-bowel wall thickening on computed tomography (CT) images can be a challenging task. Artificial intelligence (AI) support systems can improve the diagnostic accuracy of radiologists, as shown for a variety of imaging tasks. Improvements in diagnostic performance, in particular the reduction of false-negative findings, may be useful in patient care., Objective: To develop and evaluate a deep learning algorithm able to differentiate colon carcinoma (CC) and acute diverticulitis (AD) on CT images and analyze the impact of the AI-support system in a reader study., Design, Setting, and Participants: In this diagnostic study, patients who underwent surgery between July 1, 2005, and October 1, 2020, for CC or AD were included. Three-dimensional (3-D) bounding boxes including the diseased bowel segment and surrounding mesentery were manually delineated and used to develop a 3-D convolutional neural network (CNN). A reader study with 10 observers of different experience levels was conducted. Readers were asked to classify the testing cohort under reading room conditions, first without and then with algorithmic support., Main Outcomes and Measures: To evaluate the diagnostic performance, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for all readers and reader groups with and without AI support. Metrics were compared using the McNemar test and relative and absolute predictive value comparisons., Results: A total of 585 patients (AD: n = 267, CC: n = 318; mean [SD] age, 63.2 [13.4] years; 341 men [58.3%]) were included. The 3-D CNN reached a sensitivity of 83.3% (95% CI, 70.0%-96.6%) and specificity of 86.6% (95% CI, 74.5%-98.8%) for the test set, compared with the mean reader sensitivity of 77.6% (95% CI, 72.9%-82.3%) and specificity of 81.6% (95% CI, 77.2%-86.1%). The combined group of readers improved significantly with AI support from a sensitivity of 77.6% to 85.6% (95% CI, 81.3%-89.3%; P < .001) and a specificity of 81.6% to 91.3% (95% CI, 88.1%-94.5%; P < .001). Artificial intelligence support significantly reduced the number of false-negative and false-positive findings (NPV from 78.5% to 86.4% and PPV from 80.9% to 90.8%; P < .001)., Conclusions and Relevance: The findings of this study suggest that a deep learning model able to distinguish CC and AD in CT images as a support system may significantly improve the diagnostic performance of radiologists, which may improve patient care.

Introduction: Practicing endoscopic procedures is fundamental for the education of clinicians and the benefit of patients. Despite a diverse variety of model types, there is no system simulating anatomical restrictions and variations in a flexible and atraumatic way. Our goal was to develop and validate a new modelling approach for adhesion forces between colon and abdominal wall., Methods: An inlay for a standard mechanical trainer was designed and 3D printed. Colon specimens were fixed to the inlay along colon ascendens (CA) and colon descendens (CD) by a vacuum. Our system, which we refer to as Colonoscopy Vacuum Model (CoVaMo), was validated with 11 test persons with varying level of expertise. Each performed one colonoscopy and one polypectomy in the CoVaMo and in the Endoscopic Laparoscopic Interdisciplinary Training Entity (ELITE). Achieved adhesion forces, times required to fulfill different tasks endoscopically and a questionnaire, assessing proximity to reality, were recorded., Results: Mean adhesion forces of 37 ± 7 N at the CA and 30 ± 15 N at the CD were achieved. Test subjects considered CoVaMo more realistic than ELITE concerning endoscope handling and the overall anatomy. Participants needed statistically significantly more time to maneuver from anus to flexura sinistra in CoVaMo (377 s ± 244 s) than in ELITE (58 s ± 49 s)., Conclusion: We developed a training environment enabling anatomically and procedural realistic colonoscopy training requiring participants to handle all endoscope features in parallel. Fixation forces compare to forces needed to tear pig colon off the mesentery. Workflow and inlay can be adapted to any arbitrary ex vivo simulator., (© 2022. The Author(s).)

Background: Colorectal anastomoses are among the most commonly performed interventions in abdominal surgery, while associated patient trauma is still high. Most recent trends of endoscopic anastomosis devices integrate magnetic components to overcome the challenges of minimally invasive surgery. However, the mutual attraction between magnetic implant halves may increase the risk of inadvertently pinching healthy structures. Thus, we present a novel anastomosis device to improve system controllability and flexibility., Methods: A magnetic implant and an applicator with electromagnetic control units were developed. The interaction of magnetic implants with the electromagnets bears particular challenges with respect to the force-related dimensioning. Here, attraction forces must be overcome by the electromagnet actuation to detach the implant, while the attraction force between the implant halves must be sufficient to ensure a stable connection. Thus, respective forces were measured and the detachment process was reproducibly investigated. Patient hazards, associated with resistance-related heating of the coils were investigated., Results: Anastomosis formation was reproducibly successful for an implant, with an attraction force of 1.53 [Formula: see text], resulting in a compression pressure of [Formula: see text]. The implant was reproducibly detachable from the applicator at the anastomosis site. Coils heated up to a maximum temperature of [Formula: see text]. Furthermore, we were able to establish a neat reconnection of intestinal bowel endings using our implant., Discussion: As we achieved nearly equal compression forces with our implant as other magnetic anastomosis systems did (Magnamosis™: 1.48 N), we concluded that our approach provides sufficient holding strength to counteract the forces acting immediately postoperatively, which would eventually lead to an undesired slipping of the implant halves during the healing phase. Based on heat transfer investigations, preventive design specifications were derived, revealing that the wall thickness of a polymeric isolation is determined rather by stability considerations, than by heat shielding requirements., (© 2022. The Author(s).)

The rate of abdominal surgical interventions and associated postoperative complications in inflammatory bowel disease (IBD) patients is still substantially high. There is an ongoing debate as to whether or not patients who undergo treatment with anti-tumor necrosis factor-alpha (TNF-α) agents may have an increased risk for general and surgical postoperative complications. Therefore, a systematic review and meta-analysis was conducted in order to assess the effect of anti-TNF-α treatment within 12 weeks (washout period) prior to abdominal surgery on 30-day postoperative complications in patients with IBD. The results of previously published meta-analyses examining the effect of preoperative anti-TNF-α treatment on postoperative complications reported conflicting findings which is why we specifically focus on the effect of anti-TNF-α treatment within 12 weeks prior to surgery. PubMed, Cochrane, Scopus, Web of Science, World Health Organization Trial Registry, ClinicalTrials.gov and reference lists were searched (June 1995−February 2022) to identify studies, investigating effects of anti-TNF-α treatment prior to abdominal surgery on postoperative complications in IBD patients. Pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated and subgroup analyses were performed. In this case, 55 cohort studies (22,714 patients) were included. Overall, postoperative complications (OR, 1.23; 95% CI, 1.04−1.45; p = 0.02), readmission (OR, 1.39; 95% CI, 1.11−1.73; p = 0.004), and intra-abdominal septic complications (OR, 1.89; 95% CI, 1.44−2.49; p < 0.00001) were significantly higher for anti-TNF-α-treated patients. Significantly higher intra-abdominal abscesses and readmission were found for anti-TNF-α-treated CD patients (p = 0.05; p = 0.002). Concomitant treatment with immunosuppressives in <50% of anti-TNF-α-treated patients was associated with significantly lower mortality rates (OR, 0.32; 95% CI, 0.12−0.83; p = 0.02). Anti-TNF-α treatment within 12 weeks prior to surgery is associated with higher short-term postoperative complication rates (general and surgical) for patients with IBD, especially CD.

Background: Pancreatic fistula/PF is a challenging surgical complication. We could recently show that intestinal bacteria such as Enterobacterales colonize the PF fluid even after a "sterile" operation like distal pancreatectomy/DP. Therefore, we explored the bacterial flora of the human pancreatic duct in a patient collective undergoing pancreatic surgery., Methods: In this observational study, upon transection of the pancreas during surgery, a swab was inserted into the main duct, and the micro-organismal content was correlated with clinical characteristics., Results: Between February 2017 and February 2020, an intraoperative swab from the pancreatic duct was obtained from a total of 54 patients who underwent pancreatico-duodenectomy/PD or DP. The swabs were sterile in 39 cases (72.2%), detected intestinal bacteria in 10 cases (18.5%), and other bacteria in 5 cases (9.3%). There was no correlation of the micro-organismal content of the pancreatic duct swab with bacteria detected in the PF fluid or bile. Preoperative ERCP was associated with a higher frequency of bacterial colonization of the pancreatic duct (33.3% vs. 6.7%, p = 0.005). There was no correlation of the pancreatic duct swabs with postoperative complications., Discussion: The human main pancreatic duct is usually sterile, and its bacterial colonization does not correlate with the occurrence of PF. Therefore, the mechanisms leading to infection of PF warrant in-depth, mechanistic investigation., Competing Interests: All affiliations for all co-authors are listed on the title page of the manuscript., (© 2022 The Author(s).)

Background: Personalized medicine requires the integration and analysis of vast amounts of patient data to realize individualized care. With Surgomics, we aim to facilitate personalized therapy recommendations in surgery by integration of intraoperative surgical data and their analysis with machine learning methods to leverage the potential of this data in analogy to Radiomics and Genomics., Methods: We defined Surgomics as the entirety of surgomic features that are process characteristics of a surgical procedure automatically derived from multimodal intraoperative data to quantify processes in the operating room. In a multidisciplinary team we discussed potential data sources like endoscopic videos, vital sign monitoring, medical devices and instruments and respective surgomic features. Subsequently, an online questionnaire was sent to experts from surgery and (computer) science at multiple centers for rating the features' clinical relevance and technical feasibility., Results: In total, 52 surgomic features were identified and assigned to eight feature categories. Based on the expert survey (n = 66 participants) the feature category with the highest clinical relevance as rated by surgeons was "surgical skill and quality of performance" for morbidity and mortality (9.0 ± 1.3 on a numerical rating scale from 1 to 10) as well as for long-term (oncological) outcome (8.2 ± 1.8). The feature category with the highest feasibility to be automatically extracted as rated by (computer) scientists was "Instrument" (8.5 ± 1.7). Among the surgomic features ranked as most relevant in their respective category were "intraoperative adverse events", "action performed with instruments", "vital sign monitoring", and "difficulty of surgery"., Conclusion: Surgomics is a promising concept for the analysis of intraoperative data. Surgomics may be used together with preoperative features from clinical data and Radiomics to predict postoperative morbidity, mortality and long-term outcome, as well as to provide tailored feedback for surgeons., (© 2022. The Author(s).)

Background: Pathological TNM staging (pTNM) is the strongest prognosticator in colorectal carcinoma (CRC) and the foundation of its post-operative clinical management. Tumours that invade pericolic/perirectal adipose tissue generally fall into the pT3 category without further subdivision., Methods: The histological depth of invasion into the pericolic/perirectal fat was digitally and conventionally measured in a training cohort of 950 CRCs (Munich). We biostatistically calculated the optimal cut-off to stratify pT3 CRCs into novel pT3a (≤3 mm)/pT3b (>3 mm) subgroups, which were then validated in two independent cohorts (447 CRCs, Bayreuth/542 CRCs, Mainz)., Results: Compared to pT3a tumours, pT3b CRCs showed significantly worse disease-specific survival, including in pN0 vs pN+ and colonic vs. rectal cancers (DSS: P < 0.001, respectively, pooled analysis of all cohorts). Furthermore, the pT3a/pT3b subclassification remained an independent predictor of survival in multivariate analyses (e.g. DSS: P < 0.001, hazard ratio: 4.41 for pT3b, pooled analysis of all cohorts). While pT2/pT3a CRCs showed similar survival characteristics, pT3b cancers remained a distinct subgroup with dismal survival., Discussion: The delineation of pT3a/pT3b subcategories of CRC based on the histological depth of adipose tissue invasion adds valuable prognostic information to the current pT3 classification and implementation into current staging practices of CRC should be considered., (© 2022. The Author(s).)

The current crisis surrounding the COVID-19 pandemic demonstrates the amount of responsibility and the workload on our healthcare system and, above all, on the medical staff around the world. In this work, we propose a promising approach to overcome this problem using robot-assisted telediagnostics, which allows medical experts to examine patients from distance. The designed telediagnostic system consists of two robotic arms. Each robot is located at the doctor and patient sites. Such a system enables the doctor to have a direct conversation via telepresence and to examine patients through robot-assisted inspection (guided tactile and audiovisual contact). The proposed bilateral teleoperation system is redundant in terms of teleoperation control algorithms and visual feedback. Specifically, we implemented two main control modes: joint-based and displacement-based teleoperation. The joint-based mode was implemented due to its high transparency and ease of mapping between Leader and Follower whereas the displacement-based is highly flexible in terms of relative pose mapping and null-space control. Tracking tests between Leader and Follower were conducted on our system using both wired and wireless connections. Moreover, our system was tested by seven medical doctors in two experiments. User studies demonstrated the system's usability and it was successfully validated by the medical experts.

Background: Research in the field of surgery is mainly driven by aiming for trauma reduction as well as for personalized treatment concepts. Beyond laparoscopy, other proposed approaches for further reduction of the therapeutic trauma have failed to achieve clinical translation, with few notable exceptions. We believe that this is mainly due to a lack of flexibility and high associated costs. We aimed at addressing these issues by developing a novel minimally invasive operating platform and a preoperative design workflow for patient-individual adaptation and cost-effective rapid manufacturing of surgical manipulators. In this article, we report on the first in-vitro cholecystectomy performed with our operating platform., Methods: The single-port overtube (SPOT) is a snake-like surgical manipulator for minimally invasive interventions. The system layout is highly flexible and can be adapted in design and dimensions for different kinds of surgery, based on patient- and disease-specific parameters. For collecting and analyzing this data, we developed a graphical user interface, which assists clinicians during the preoperative planning phase. Other major components of our operating platform include an instrument management system and a non-sterile user interface. For the trial surgery, we used a validated phantom which was further equipped with a porcine liver including the gallbladder., Results: Following our envisioned preoperative design workflow, a suitable geometry of the surgical manipulator was determined for our trial surgery and rapidly manufactured by means of 3D printing. With this setup, we successfully performed a first in-vitro cholecystectomy, which was completed in 78 min., Conclusions: By conducting the trial surgery, we demonstrated the effectiveness of our PLAFOKON operating platform. While some aspects - especially regarding usability and ergonomics - can be further optimized, the overall performance of the system is highly promising, with sufficient flexibility and strength for conducting the necessary tissue manipulations., (© 2021. The Author(s).)

Purpose: Today's hospitals are designed as collections of individual departments, with limited communication and collaboration between medical sub-specialties. Patients are constantly being moved between different places, which is detrimental for patient experience, overall efficiency and capacity. Instead, we argue that care should be brought to the patient, not vice versa, and thus propose a novel hospital architecture concept that we refer to as Patient Hub. It envisions a truly patient-centered, department-less facility, in which all critical functions occur in the same building and on the same floor., Methods: To demonstrate the feasibility and benefits of our concept, we selected an exemplary patient scenario and used 3D software to simulate resulting workflows for both the Patient Hub and a traditional hospital based on a generic hospital template by Kaiser-Permanente., Results: According to our workflow simulations, the Patient Hub model effectively eliminates waiting and transfer times, drastically simplifies wayfinding, reduces overall traveling distances by 54%, reduces elevator runs by 78% and improves access to quality views from 67 to 100% for patient rooms, from 0 to 100% for exam rooms and from 0 to 38% for corridors. In addition, the interaction of related medical fields is improved while maintaining the quality of care and the relationship between patients and caregivers., Conclusion: With the Patient Hub concept, we aim at rethinking traditional hospital layouts. We were able to demonstrate, alas on a proof-of-concept basis, that it is indeed feasible to place the patient at the very center of operations, while increasing overall efficiency and capacity at the same time and maintaining the quality of care., (© 2021. CARS.)

Background: Digitalization affects almost every aspect of modern daily life, including a growing number of health care services along with telemedicine applications. Fifth-generation (5G) mobile communication technology has the potential to meet the requirements for this digitalized future with high bandwidths (10 GB/s), low latency (<1 ms), and high quality of service, enabling wireless real-time data transmission in telemedical emergency health care applications., Objective: The aim of this study is the development and clinical evaluation of a 5G usability test framework enabling preclinical diagnostics with mobile ultrasound using 5G network technology., Methods: A bidirectional audio-video data transmission between the ambulance car and hospital was established, combining both 5G-radio and -core network parts. Besides technical performance evaluations, a medical assessment of transferred ultrasound image quality and transmission latency was examined., Results: Telemedical and clinical application properties of the ultrasound probe were rated 1 (very good) to 2 (good; on a 6 -point Likert scale rated by 20 survey participants). The 5G field test revealed an average end-to-end round trip latency of 10 milliseconds. The measured average throughput for the ultrasound image traffic was 4 Mbps and for the video stream 12 Mbps. Traffic saturation revealed a lower video quality and a slower video stream. Without core slicing, the throughput for the video application was reduced to 8 Mbps. The deployment of core network slicing facilitated quality and latency recovery., Conclusions: Bidirectional data transmission between ambulance car and remote hospital site was successfully established through the 5G network, facilitating sending/receiving data and measurements from both applications (ultrasound unit and video streaming). Core slicing was implemented for a better user experience. Clinical evaluation of the telemedical transmission and applicability of the ultrasound probe was consistently positive., (©Maximilian Berlet, Thomas Vogel, Mohamed Gharba, Joseph Eichinger, Egon Schulz, Helmut Friess, Dirk Wilhelm, Daniel Ostler, Michael Kranzfelder. Originally published in JMIR Formative Research (https://formative.jmir.org), 26.05.2022.)

In video-based surgery (VBS), the surgeon is no longer the master of his or her view. Visualization of the surgical field is mediated by a video camera guided by an assistant. The separation of visualization and surgical activities leads to significant drawbacks. Early in the history of VBS, active camera holders controlled directly by the surgeon were introduced to replace the human camera assistant. However, despite remarkable technological advances over the past 25 years, robotic camera guidance systems (RCGS) still play only a marginal role. This is less due to inadequate mechanical designs or kinematics, and mainly due to inadequate human-machine interaction. In most cases, a simple task-shift is required that increases the surgeon's mental workload instead of reducing it. The current state of the art in robotic camera guidance, as represented by the SOLOASSIST II RCGS (AKTORmed, Neutraubling, Germany), includes a sophisticated combination of direct manual control, joystick navigation and high-quality voice control that provides the most intuitive surgeon-machine interaction currently available. An in-depth analysis of further clinical needs and promising developments in operating room integration suggests that the addition of context sensitivity could actually enhance the assistive effect of RCGS, making them potentially superior to the average human camera guidance.

Purpose: Anastomosis creation after resective gastrointestinal surgery is a crucial task. The present review examines the techniques and implants currently available for anastomosis creation and analyses to which extent they already address our clinical needs, with a special focus on their potential to enable further trauma minimization in visceral surgery., Methods: A multi-database research was conducted in MEDLINE, Scopus, and Cochrane Library. Comparative controlled and uncontrolled clinical trials dealing with anastomosis creation techniques in the intestinal tract in both German and English were included and statistically significant differences in postoperative complication incidences were assessed using the RevMan5.4 Review Manager (Cochrane Collaboration, Oxford, UK)., Results: All methods and implant types were analyzed and compared with respect to four dimensions, assessing the techniques' current performances and further potentials for surgical trauma reduction. Postoperative outcome measures, such as leakage, stenosis, reoperation and mortality rates, as well as the tendency to cause bleeding, wound infections, abscesses, anastomotic hemorrhages, pulmonary embolisms, and fistulas were assessed, revealing the only statistically significant superiority of hand-suture over stapling anastomoses with respect to the occurrence of obstructions., Conclusion: Based on the overall complication rates, it is concluded that none of the anastomosis systems addresses the demands of operative trauma minimization sufficiently yet. Major problems are furthermore either low standardization potentials due to dependence on the surgeons' levels of experience, high force application requirements for the actual anastomosis creation, or large and rigid device designs interfering with flexibility demands and size restrictions of the body's natural access routes. There is still a need for innovative technologies, especially with regard to enabling incisionless interventions., Competing Interests: Prof. Wilhelm, Prof. Mela, Dr. Eblenkamp, Dr. Jell, Mr. Ostler, Ms. Ficht and Ms. Steger report grants from DFG, German Research Foundation, during the conduct of the study. In addition, Prof. Wilhelm, Prof. Mela, Dr. Eblenkamp, Mr. Ostler, Ms. Ficht and Ms. Steger have two patents pending; 1) Clamping device and applicator for joining flexible tubular walls (International publication number: WO 2022/049196 A1) and 2) Implant and implant applicator for surgical anastomosis (International publication number: WO2022/049197 A1). The authors report no other conflicts of interest in this work., (© 2022 Steger et al.)

When two or more users attempt to collaborate in the same space with Augmented Reality, they often encounter conflicting intentions regarding the occupation of the same working area and self-positioning around such without mutual interference. Augmented Reality is a powerful tool for communicating ideas and intentions during a co-assisting task that requires multi-disciplinary expertise. To relax the constraint of physical co-location, we propose the concept of Duplicated Reality, where a digital copy of a 3D region of interest of the users' environment is reconstructed in real-time and visualized in-situ through an Augmented Reality user interface. This enables users to remotely annotate the region of interest while being co-located with others in Augmented Reality. We perform a user study to gain an in-depth understanding of the proposed method compared to an in-situ augmentation, including collaboration, effort, awareness, usability, and the quality of the task. The result indicates almost identical objective and subjective results, except a decrease in the consulting user's awareness of co-located users when using our method. The added benefit from duplicating the working area into a designated consulting area opens up new interaction paradigms to be further investigated for future co-located Augmented Reality collaboration systems.

Purpose: In current clinical practice, intraoperative repositioning of mobile C-arms is challenging due to a lack of visual cues and efficient guiding tools. This can be detrimental to the surgical workflow and lead to additional radiation burdens for both patient and personnel. To overcome this problem, we present our novel approach Lidar-based X-ray Positioning for Mobile C-arms (RAY-POS) for assisting circulating nurses during intraoperative C-arm repositioning without requiring external aids., Methods: RAY-POS consists of a localization module and a graphical user interface for guiding the user back to a previously recorded C-Arm position. We conducted a systematic comparison of simultaneous localization and mapping (SLAM) algorithms using different attachment positions of light detection and ranging (LIDAR) sensors to benchmark localization performance within the operating room (OR). For two promising combinations, we conducted further end-to-end repositioning tests within a realistic OR setup., Results: SLAM algorithm gmapping with a LIDAR sensor mounted 40 cm above the C-arm's horizontal unit performed best regarding localization accuracy and long-term stability. The distribution of the repositioning error yielded an effective standard deviation of 7.61 mm., Conclusion: We conclude that a proof-of-concept for LIDAR-based C-arm repositioning without external aids has been achieved. In future work, we mainly aim at extending the capabilities of our system and evaluating the usability together with clinicians., (© 2022. The Author(s).)

Purpose: While demand for telemedicine is increasing, patients are currently restricted to tele-consultation for the most part. Fundamental diagnostics like the percussion still require the in person expertize of a physician. To meet today's challenges, a transformation of the manual percussion into a standardized, digital version, ready for telemedical execution is required., Methods: In conjunction with a comprehensive telemedical diagnostic system, in which patients can get examined by a remote-physician, a series of three robotic end-effectors for mechanical percussion were developed. Comprising a motor, a magnetic and a pneumatic-based version, the devices strike a pleximeter to perform the percussion. Emitted sounds were captured using a microphone-equipped stethoscope. The 84 recordings were further integrated into a survey in order to classify lung and non-lung samples., Results: The study with 21 participants comprised physicians, medical students and non-medical-related raters in equal parts. With 71.4% correctly classified samples, the ventral motorized device prevailed. While the result is significantly better compared to a manual or pneumatic percussion in this very setup, it only has a small edge over the magnetic devices. In addition, for all ventral versions non-lung regions were rather correctly identified than lung regions., Conclusion: The overall setup proves the feasibility of a telemedical percussion. Despite the fact, that produced sounds differ compared to today's manual technique, the study shows that a standardized mechanical percussion has the potential to improve the gold standard's accuracy. While further extensive medical evaluation is yet to come, the system paves the way for future uncompromised remote examinations., (© 2021. The Author(s).)

The B subunit of bacterial Shiga toxin (STxB) is nontoxic and has low immunogenicity. Its receptor, the glycosphingolipid Gb3/CD77, is overexpressed on the cell surface of human colorectal cancer. We tested whether genetic porcine models, closely resembling human anatomy and pathophysiology, can be used to exploit the tumor-targeting potential of STxB. In accordance with findings on human colorectal cancer, the pig model APC1311 bound STxB in colorectal tumors, but not in normal colon or jejunum, except for putative enteroendocrine cells. In primary tumor cells from endoscopic biopsies, STxB was rapidly taken up along the retrograde intracellular route to the Golgi, whereas normal colon organoids did not bind or internalize STxB. Next, we tested a porcine model (TP53LSL-R167H) for osteosarcoma, a tumor entity with a dismal prognosis and insufficient treatment options, hitherto not known to express Gb3. Pig osteosarcoma strongly bound StxB and expressed the Gb3 synthase 1,4-galactosyltransferase (A4GALT). Primary osteosarcoma cells, but not normal osteoblasts, rapidly internalized fluorescently labeled STxB along the retrograde route to the Golgi. Importantly, six of eight human osteosarcoma cell lines expressed A4GALT mRNA and showed prominent intracellular uptake of STxB. The physiologic role of A4GALT was tested by CRISPR/Cas9 mutagenesis in porcine LLC-PK1 kidney epithelial cells and RNAi in MG-63 human osteosarcoma cells. A4GALT deficiency or knockdown abolished STxB uptake and led to significantly reduced cell migration and proliferation, hinting toward a putative tumor-promoting role of Gb3. Thus, pig models are suitable tools for STxB-based tumor targeting and may allow "reverse-translational" predictions on human tumor biology., (©2022 American Association for Cancer Research.)

Ethical, legal and social aspects are gaining increasingly more attention in the development and during the initial clinical application of medical devices. The introduction of elements of artificial intelligence (AI) and systems which are using AI makes this already complex topic even more challenging. The introduction of so-called dynamic AI or dynamic machine learning (ML) algorithms in this respect represents a turning point. Unlike conventional medical devices, the development of systems using dynamic AI is not yet complete at the beginning of the clinical application. The aim of a dynamic AI system is to continuously improve through practical use and by the processing of usage data. This continuous evolution, along with the lack of transparency regarding internal work processes, could make it difficult to understand the underlying rationale for the assessments made by the algorithms. This aspect affects the acceptance of the technology both by clinicians and patients and furthermore questions the autonomy of patients and clinicians in the course of the treatment process. A way out of this ethical and regulatory dilemma must urgently be found and will require extreme efforts from all stakeholders. At present, no consensual solution is apparent. What is quite certain, however, is that users, i.e. in concrete terms surgeons, must play a much more active role than they have done in the past when dealing with AI-based medical devices and should prepare themselves to actively accompany the software life cycle of AI technologies., (© 2022. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Background: Special AT-rich sequence-binding protein 2 (SATB2) has emerged as an alternative immunohistochemical marker to CDX2 for colorectal differentiation. However, the distribution and prognostic relevance of SATB2 expression in colorectal carcinoma (CRC) have to be further elucidated., Methods: SATB2 expression was analysed in 1039 CRCs and correlated with clinicopathological and morphological factors, CDX2 expression as well as survival parameters within the overall cohort and in clinicopathological subgroups., Results: SATB2 loss was a strong prognosticator in univariate analyses of the overall cohort ( p < 0.001 for all survival comparisons) and in numerous subcohorts including high-risk scenarios (UICC stage III/high tumour budding). SATB2 retained its prognostic relevance in multivariate analyses of these high-risk scenarios (e.g., UICC stage III: DSS: p = 0.007, HR: 1.95), but not in the overall cohort (DSS: p = 0.1, HR: 1.25). SATB2 loss was more frequent than CDX2 loss (22.2% vs. 10.2%, p < 0.001) and of higher prognostic relevance with only moderate overlap between SATB2/CDX2 expression groups., Conclusions: SATB2 loss is able to identify especially aggressive CRCs in high-risk subgroups. While SATB2 is the prognostically superior immunohistochemical parameter compared to CDX2 in univariate analyses, it appears to be the less sensitive marker for colorectal differentiation as it is lost more frequently.

Background: Immunohistochemical loss of CDX2 has been proposed as a biomarker of dismal survival in colorectal carcinoma (CRC), especially in UICC Stage II/III. However, it remains unclear, how CDX2 expression is related to central hematoxylin-eosin (HE)-based morphologic parameters defined by 2019 WHO classification and how its prognostic relevance is compared to these parameters., Methods: We evaluated CDX2 expression in 1003 CRCs and explored its prognostic relevance compared to CRC subtypes, tumour budding and WHO grade in the overall cohort and in specific subgroups., Results: CDX2-low/absent CRCs were enriched in specific morphologic subtypes, right-sided and microsatellite-instable (MSI-H) CRCs (P < 0.001) and showed worse survival characteristics in the overall cohort/UICC Stage II/III (e.g. DFS: P = 0.005) and in microsatellite stable and left-sided CRCs, but not in MSI-H or right-sided CRCs. Compared with CDX2, all HE-based markers showed a significantly better prognostic discrimination in all scenarios. In multivariate analyses including all morphologic parameters, CDX2 was not an independent prognostic factor., Conclusion: CDX2 loss has some prognostic impact in univariate analyses, but its prognostic relevance is considerably lower compared to central HE-based morphologic parameters defined by the WHO classification and vanishes in multivariate analyses incorporating these factors., (© 2021. The Author(s).)

Apart from the tremendous increase in the demand for telemedicine during the COVID-19 pandemic, the use of telemedical technology offers many advantages, such as better coverage of rural areas and improved access to specialists. While current telediagnostic possibilities are often limited to a verbal consultation, the field of surgery has already made use of robotics for one of the most challenging areas of medicine: invasive procedures. Since comprehensive diagnostics are a prerequisite for each surgery, we built upon the knowledge gained in telesurgery and developed a telediagnostic system that allows for an extensive perioperative and emergency examination. It is based on a robotic platform consisting of a remote lead robotic arm at the physician's site and a follower robot at the patient's site. Mirroring all movements directly and using force-feedback, both parties can precisely interact, enabling tasks such as auscultation, percussion, and palpation without the need for extensive training. Our overall setup also includes the possibility to measure and monitor all relevant vital parameters and can be used to perform ear and nasopharyngeal inspections as well as an automatic swab to screen for COVID or other contagious diseases prior to hospital admission. In this paper, we focus on the potential of this technology for the surgical community by demonstrating the ease of adding an ultrasound probe to our modular setup to perform a high-quality emergency ultrasound examination. While the system is not yet ready for everyday use in a hospital and drawbacks such as a high cost persist, our setup paves the way for the future use of telediagnostics in surgery.

Objectives: Due to the coronavirus disease 2019 (Covid-19) pandemic, all scientific conferences in the year 2020 had to be adapted in their form of presence to accommodate for safety regulations, postponed, or canceled entirely. As organizers of the annual Computer Assisted Radiology & Surgery International Conference & Exhibition (CARS)-Conference 2020, we decided to hold a "hybrid" conference, i.e., a virtual conference with partial presence to mitigate the drawbacks of a purely virtual conference. It is the purpose of this paper to describe the results and experience gained by our first hybrid conference., Methods: Besides technical necessities like an online conferencing tool, we introduced additional personal namely the technical chairs and communication officers ensuring a smooth flow of presentations. To measure the success of the hybrid conference, we assessed various parameters during the conference (e.g., counting of adverse events, delays, and no-shows) and sent a questionnaire to participants for evaluation after the conference., Results: We offered four types of presentation formats, whereas the majority of speakers presented their pre-produced videos including live discussions. Significant delays in sessions occurred during the morning sessions, which could be reduced during lunch breaks. The analysis of the influence of the distribution of the audience's location/time zone toward the attendance rate showed a high relevance for the American zone and only little influence for the Asian-Pacific region. Based on the questionnaire, 60% of responders considered the hybrid approach as superior and 12% as inferior to purely virtual conferences., Conclusions: Most scientific associations in 2020 had to struggle with a dramatic change: Regular, traditional meetings with personal communication and exchange, networking, and creation of new visions became obsolete almost instantly. As an alternative, virtual conferences became increasingly popular, and are offering additional advantages (e.g., reduction of cost for travel, lodging, and time on transit). To overcome the drawbacks of purely virtual conferences, we introduced a hybrid concept for the CARS-Congress. While certainly, those with the privilege to take part personally on-site did benefit most from the hybrid format. Facing upcoming waves of the Covid-19 Pandemic, with ongoing changes to the regulations on meetings and transit, hybrid conferences are a viable option for scientific conferences for the future., Competing Interests: Competing interests: Authors state no conflict of interest., (© 2021 Daniel Ostler et al., published by De Gruyter, Berlin/Boston.)

Purpose: Despite primary conservative therapy for Crohn's disease, a considerable proportion of patients ultimately needs to undergo surgery. Presumably, due to the increased use of biologics, the number of surgeries might have decreased. This study aimed to delineate current case numbers and trends in surgery in the era of biological therapy for Crohn's disease., Methods: Nationwide standardized hospital discharge data (diagnosis-related groups statistics) from 2010 to 2017 were used. All patients who were admitted as inpatient Crohn's disease cases in Germany were included. Time-related development of admission numbers, rate of surgery, morbidity, and mortality of inpatient Crohn's disease cases were analyzed., Results: A total number of 201,165 Crohn's disease cases were included. Within the analyzed time period, the total number of hospital admissions increased by 10.6% (n = 23,301 vs. 26,069). While gender and age distribution remained comparable, patients with comorbidities such as stenosis formation (2010: 10.1%, 2017: 13.4%) or malnutrition (2010: 0.8%, 2017: 3.2%) were increasingly admitted. The total number of all analyzed operations for Crohn's disease increased by 7.5% (2010: n = 1567; 2017: n = 1694). On average, 6.8 ± 0.2% of all inpatient patients received ileocolonic resections. Procedures have increasingly been performed minimally invasive (2010: n = 353; 2017: n = 687). The number of postoperative complications remained low., Conclusion: Despite the development of novel immunotherapeutics, the number of patients requiring surgery for Crohn's disease remains stable. Interestingly, patients have been increasingly hospitalized with stenosis and malnutrition. The trend towards more minimally invasive operations has not relevantly changed the rate of overall complications., (© 2021. The Author(s).)