SonicGuard Sensor-A Multichannel Acoustic Sensor for Long-Term Monitoring of Abdominal Sounds Examined through a Qualification Study.

Auscultation is a fundamental diagnostic technique that provides valuable diagnostic information about different parts of the body. With the increasing prevalence of digital stethoscopes and telehealth applications, there is a growing trend towards digitizing the capture of bodily sounds, thereby enabling subsequent analysis using machine learning algorithms. This study introduces the SonicGuard sensor, which is a multichannel acoustic sensor designed for long-term recordings of bodily sounds. We conducted a series of qualification tests, with a specific focus on bowel sounds ranging from controlled experimental environments to phantom measurements and real patient recordings. These tests demonstrate the effectiveness of the proposed sensor setup. The results show that the SonicGuard sensor is comparable to commercially available digital stethoscopes, which are considered the gold standard in the field. This development opens up possibilities for collecting and analyzing bodily sound datasets using machine learning techniques in the future.

Effects of intensive physiotherapy on Quality of Life (QoL) after pancreatic cancer resection: a randomized controlled trial.

BACKGROUND: Patients have significantly lower QoL scores after pancreatic resection due to cancer in the physical and psychological domains compared to healthy controls or other cancer patients. Intensified physiotherapy or physical training can increase QoL by reducing fatigue levels and improving physical functioning. However, data on the long-term effects of intensive or supervised physiotherapy is lacking. The aim of this exploratory study is the assessment of QoL in the intervention group, using various QoL questionnaires in their validated German translations and gather data on its feasibility in the context of chemotherapy with a follow-up of 12 months (and develop concepts to improve QoL after pancreatic cancer resection). METHODS: Fifty-six patients (mean age: 66.4 ± 9.9 years) were randomized in this study to intervention (cohort A, n = 28) or control group (cohort B, n = 28). Intervention of intensified physiotherapy program consisted of endurance and muscle force exercises using cycle ergometer. In the control group physiotherapy was limited to the duration of the hospital stay and was scheduled for 20 min on 5 days per week. The clinical visits took place 2 days preoperatively, 1 week, 3 months, 6 months and 12 months postoperatively. Both groups attended the follow-up program. QoL was evaluated using the Short Physical Performance Battery (SPPB), Short Form-8 Health Survey (SF-8) and the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 and pancreatic cancer-specific module QLQ-PAN26 questionnaires. The course of QoL was evaluated using a repeated measures ANOVA and a per protocol design. RESULTS: Of the initial 56 randomized patients, 34 finished the 12 months follow-up period. There were no adverse events due to the intervention and 80% of patients in the intervention group where adherent. There was no significant influence on physical performance as measured by SPPB and SF-8 questionnaire. However, after 6 months patients in the intervention group regained their prior physical condition, whereas the control group did not. Intensive physiotherapy significantly influenced various factors of QoL measured with the C30 questionnaire positively, such as physical functioning (p = 0.018), role functioning (p = 0.036), and appetite loss (p = 0.037), even after 6 months. No negative effects in patients undergoing chemotherapy compared to those without chemotherapy was observed. CONCLUSION: This first randomized controlled study with a 12-month follow-up shows that supervised physiotherapy or prescribed home-based exercise after pancreatic cancer resection is safe and feasible and should be proposed and started as soon as possible to improve certain aspects of QoL. TRIAL REGISTRATION: German Clinical Trials Register (No: DRKS00006786 ); Date of registration: 01/10/2014.

The development of visuospatial abilities and their impact on laparoscopic skill acquisition: a clinical longitudinal study.

OBJECTIVES: To investigate how visuospatial abilities develop and influence intraoperative laparoscopic performance during surgical residency training programmes. BACKGROUND: Laparoscopic surgery is a challenging technique to acquire and master. Visuospatial ability is an important attribute but most prior research have predominantly explored the influence of visuospatial abilities in lab-based settings and/or among inexperienced surgeons. Little is known about the impact of visuospatial profiles on actual laparoscopic performance and its role in shaping competency. METHOD: A longitudinal observational cohort study using a pair-matched design over 27 months. At baseline, visuospatial profiles of 43 laparoscopic surgeons of all expertise levels and 19 control subjects were compared. The development of visuospatial abilities and their association with intraoperative performance of 18 residency surgeons were monitored during the course of their laparoscopic training. RESULTS: Laparoscopic surgeons significantly outperformed the control group on the measure of spatial visualisation (U = 273.0, p = 0.03, η2 = 0.3). Spatial visualisation was found to be a significant predictor of laparoscopic expertise (R2 = 0.70, F (1.60) = 6.788, p = 0.01) and improved with laparoscopic training (B = 4.01, SE = 1.83, p = 0.02, 95% CI [0.40, 7.63]). From month 6 to 18, a strong positive correlation between spatial visualisation and intraoperative depth perception (r = 0.67, p < 0.01), bimanual dexterity (r = 0.60, p < 0.01), autonomy (r = 0.78, p < 0.01) and the total score (r = 0.70, p < 0.01) were observed but a strong relationship remained only with autonomy (r = 0.89, p < 0.01) and total score (r = 0.80, p < 0.01) at 18 months. CONCLUSION: In this longitudinal cohort study, visuospatial abilities associate with laparoscopic skills and improve with training. Spatial visualisation may be characteristic of laparoscopic expertise as it has clear association with competency development during laparoscopy residency training programme.

Weighted expectile regression for right-censored data.

Expectile regression can be used to analyze the entire conditional distribution of a response, omitting all distributional assumptions. Among its benefits are computational simplicity, efficiency, and the possibility to incorporate a semiparametric predictor. Due to its advantages in full data settings, we propose an extension to right-censored data situations, where conventional methods typically focus only on mean effects. We propose to extend expectile regression with inverse probability weights. Estimates are easy to implement and computationally simple. Expectiles can be converted to more easily interpreted tail expectations, that is, the expected residual life. It provides a meaningful effect measure, similar to the hazard rate. The results from an extensive simulation study are presented, evaluating consistency and sensitivity to violations of assumptions. We use the proposed method to analyze survival times of colorectal cancer patients from a regional certified high volume cancer center.

Predictors of adenoma size and location in primary hyperparathyroidism.

PURPOSE: In primary hyperparathyroidism (PHPT), intraoperative localization of the parathyroid adenoma can be challenging, especially in cases of negative preoperative imaging. Since a focused unilateral parathyroidectomy has benefits compared to a conventional bilateral neck exploration, the question arises whether adenoma size prediction can facilitate a targeted approach. We investigated whether single parathyroid adenoma size can be estimated using preoperative parathyroid hormone (PTH), calcium, and phosphate in patients with PHPT. Preoperative imaging accuracy was evaluated. METHODS: The data of 156 patients who underwent curative parathyroidectomy for single adenoma PHPT were analyzed retrospectively. Information obtained included laboratory data, imaging results, intraoperative data, and final pathology. Imaging accuracy was analyzed descriptively. The association between preoperative biochemical markers and adenoma dimensions was investigated using Spearman's correlation coefficient and multivariable regression modeling. RESULTS: Cervical ultrasound correctly predicted adenoma laterality in 95.5%, sestamibi scintigraphy in 80.6%, both had lower true-positive rates for quadrant prediction. Patients with negative imaging results showed higher thyroid volumes than those with positive results. Adenoma volume was positively correlated with preoperative PTH (p < 0.001) and calcium (p < 0.001) and negatively correlated with preoperative phosphate (p = 0.001). Using these preoperative biochemical markers and patient age and BMI, adenoma volume can be significantly predicted using the multivariable regression algorithm. CONCLUSION: Cervical ultrasound is superior to scintigraphy for predicting adenoma location and should be the first-choice imaging method, but both methods may be limited by increased thyroid volume. Large adenomas are more likely with higher PTH, higher calcium, and lower phosphate levels. In cases of undetermined adenoma location, an estimation of adenoma volume via our algorithm could corroborate sonographic volume measurements of the suspected adenoma.

Spermatic cord liposarcomas incidentally found during hernia surgery: is histology of any lipoma mandatory? A review of the literature.

Purpose: Liposarcomas found incidentally during open or laparoscopic inguinal hernia surgery are extremely rare. It is unclear, whether any adipose tissue being removed during inguinal hernia surgery must be sent for histology due to the potential risk of liposarcoma of the spermatic cord. This study aims to evaluate the frequency of liposarcomas incidentally found in the inguinal canal during hernia surgery and tries to derive evidence-based recommendations regarding the optimal management of any fatty tissue found in the inguinal canal.Methods: A literature review of the PubMed/Medline electronic databases between January 1980 and January 2019 was performed using the search terms 'inguinal hernia' and 'liposarcoma'. There was only one study available on this topic. Therefore, an additional literature review was performed analyzing all reports on patients with incidentally detected liposarcomas of the spermatic cord in the inguinal canal during hernia surgery.Results: There was only one retrospective study evaluating the frequency of inguinal liposarcoma found at hernia operations with a frequency of less than 0.1%. There were 18 cases of spermatic cord liposarcomas that were truly found incidentally during operation for an unsuspected symptomatic or incarcerated inguinal hernia. These included 16 case reports with a total of 18 patients and 19 liposarcomas. All patients were male with a median age of 62.5 years (range: 24-86 years) years. Median size of liposarcoma was 10.5 cm (range: 3-30 cm). In seven patients, the inguinal liposarcoma was an extension of a retroperitoneal sarcoma. Treatment consisted of radical orchidectomy during the primary operation in 12 patients. Three out of the seven patients with retroperitoneal extension of the tumor underwent a secondary operation with complete resection of the tumor.Conclusions: Currently, there is no evidence-based recommendation available regarding the management of lipomas detected during open or laparoscopic inguinal hernia surgery. Due to the extremely low risk of the presence of a liposarcoma, routine histologic examination cannot be recommended unless the diameter exceeds 10 cm.

Lichtenstein Versus Total Extraperitoneal Patch Plasty Versus Transabdominal Patch Plasty Technique for Primary Unilateral Inguinal Hernia Repair: A Registry-based, Propensity Score-matched Comparison of 57,906 Patients.

OBJECTIVE: Outcome comparison of the Lichtenstein, total extraperitoneal patch plasty (TEP), and transabdominal patch plasty (TAPP) techniques for primary unilateral inguinal hernia repair. BACKGROUND: For comparison of these techniques the number of cases included in meta-analyses of randomized controlled trials is limited. There is therefore an urgent need for more comparative data. METHODS: In total, 57,906 patients with a primary unilateral inguinal hernia and 1-year follow up from the Herniamed Registry were selected between September 1, 2009 and February 1, 2015. Using propensity score matching, 12,564 matched pairs were formed for comparison of Lichtenstein versus TEP, 16,375 for Lichtenstein versus TAPP, and 14,426 for TEP versus TAPP. RESULTS: Comparison of Lichtenstein versus TEP revealed disadvantages for the Lichtenstein operation with regard to the postoperative complications (3.4% vs 1.7%; P < 0.001), complication-related reoperations (1.1% vs 0.8%; P = 0.008), pain at rest (5.2% vs 4.3%; P = 0.003), and pain on exertion (10.6% vs 7.7%; P < 0.001). TEP had disadvantages in terms of the intraoperative complications (0.9% vs 1.2%; P = 0.035). Likewise, comparison of Lichtenstein versus TAPP showed disadvantages for the Lichtenstein operation with regard to the postoperative complications (3.8% vs 3.3%; P = 0.029), complication-related reoperations (1.2% vs 0.9%; P = 0.019), pain at rest (5% vs 4.5%; P = 0.029), and on exertion (10.2% vs 7.8%; P < 0.001). CONCLUSIONS: TEP and TAPP were found to have advantages over the Lichtenstein operation.

Experience and dissection device are more relevant than patient-related factors for operation time in laparoscopic sigmoid resection-a retrospective 8-year observational study.

PURPOSE: Surgical outcome is influenced by multiple patient-specific factors and operative expertise of the surgeon. Clinical relevance of medical technical innovations often remains unclear even though laparoscopic surgical procedures are characterized by continual advancement of various devices. Lately, in dissection and sealing technology, fast-cutting ultrasonic scissors are combined with simultaneous bipolar coagulation (bimodal dissection device (BDD)). We investigated how this new technology, operative expertise, and patient-specific factors (body mass index, age) influence operation time in laparoscopic-assisted sigmoid resection. METHODS: Between 2008 and 2016, 161 laparoscopic sigmoid resections (52% conventional dissection device (CDD); 48% BDD) performed in a single center were retrospectively evaluated. Biometric patient data, complication rates, and surgery duration, reflecting the learning curve, were analyzed. Operations were performed by experienced surgeons (n = 3) and trainees (n = 4). RESULTS: Minor postoperative complications (e.g., impaired wound healing, non-revisional secondary bleeding) occurred in 11 cases (6.8%). Major complications (e.g., bleeding requiring revision, anastomotic leakage) were observed in 3.7%. No heat-related coagulation damage was observed. BDD reduced operation time for both experienced (CDD 150 min, BDD 125 min; p < 0.001) and trainee surgeons (CDD 169 min, BDD 135 min; p = 0.036). Reduction of operation time (indicative of a learning curve in progress) was observed for all surgeons. The curve was steeper using BDD. CONCLUSIONS: Patient-specific factors did not have a significant effect on operation time. Even taking the learning curve into account, a combination of ultrasonic dissection and simultaneous bipolar coagulation reduces operation time of laparoscopic-assisted sigmoid resection, regardless of surgeon's expertise.

Personalized medicine for locally advanced rectal cancer: five years of complete clinical response after neoadjuvant radiochemotherapy-a case report with a literature review.

We present a case report of a 73-year-old male patient with a complete clinical response following neoadjuvant radiochemotherapy of mid-rectal adenocarcinoma. The patient was initially diagnosed with stage IIIB microsatellite stable mid-rectal adenocarcinoma in February 2017. During restaging in June 2017, which included rectoscopy, endosonography, computed tomography and magnetic resonance imaging, a complete clinical response was observed. After appropriate consultation, a watch-and-wait strategy was chosen. During stringent follow-up every 3 months for the first 3 years and thereafter every 6 months, no recurrence or regrowth was observed. After the fifth year of complete clinical response, we recommended an annual follow-up. As of November 2023, the patient has no signs of recurrence or late toxicity after radiochemotherapy. The omission of resection in patients with locally advanced rectal cancer and the establishment of a watch-and-wait strategy are currently under discussion as possible treatment courses in patients with complete clinical response. Long-term data on watch-and-wait strategies for patients with a complete clinical response in locally advanced rectal cancer are rare. A clear national and international accepted standardization of follow-up programs for patients managed by a watch-and-wait strategy in the long-term is missing. Here, we report the case of a patient who had undergone a follow-up program for more than five years and discuss the current literature. Our case report and literature review highlights that a watch-and-wait strategy does not seem to increase the risk of systemic disease or compromise survival outcomes in selected locally advanced rectal cancer patients. Thus, our case contributes to the growing body of knowledge on personalized and precision medicine for rectal cancer.

A Clinical User Study Investigating the Benefits of Adaptive Volumetric Illumination Sampling.

Accurate and fast understanding of the patient's anatomy is crucial in surgical decision making and particularly important in visceral surgery. Sophisticated visualization techniques such as 3D Volume Rendering can aid the surgeon and potentially lead to a benefit for the patient. Recently, we proposed a novel volume rendering technique called Adaptive Volumetric Illumination Sampling (AVIS) that can generate realistic lighting in real-time, even for high resolution images and volumes but without introducing additional image noise. In order to evaluate this new technique, we conducted a randomized, three-period crossover study comparing AVIS to conventional Direct Volume Rendering (DVR) and Path Tracing (PT). CT datasets from 12 patients were evaluated by 10 visceral surgeons who were either senior physicians or experienced specialists. The time needed for answering clinically relevant questions as well as the correctness of the answers were analyzed for each visualization technique. In addition to that, the perceived workload during these tasks was assessed for each technique, respectively. The results of the study indicate that AVIS has an advantage in terms of both time efficiency and most aspects of the perceived workload, while the average correctness of the given answers was very similar for all three methods. In contrast to that, Path Tracing seems to show particularly high values for mental demand and frustration. We plan to repeat a similar study with a larger participant group to consolidate the results.

Requirements for the Acceptance of an App for Voice Therapy-A Usability Report Based on the "Oldenburger Logopädie App" (OLA).

OBJECTIVE: The prototype "Oldenburger Logopädie App" (OLA) was designed to support voice therapy for patients with recurrent paresis, such as to accompany homework or as a short-term substitute for regular therapy due to dropouts, such as during the COVID-19 pandemic. The treating speech and language pathologists (SLPs) unlocks videos individually applicable to the respective patients, in which the SLPs instruct the individual exercises. The app can be used without information technology knowledge or detailed instructions. MATERIALS AND METHODS: The prototype's usability was evaluated through a usability test battery (AttrakDiff questionnaire, System Usability Scale, Visual Aesthetics of Websites Inventory questionnaire) and informal interviews from the perspective of patients and SLPs. RESULTS: The acceptance, usability, user experience, self-descriptiveness, and user behavior of OLA were consistently given and mostly rated as positive. Both user groups rated OLA as practical and easy to use (eg, System Usability Scale: "practical" (agree: ∅ 49.5%), "cumbersome to use" (total: strongly disagree: ∅ 60.0%). However, the monotonous layout of the app and the instructional and exercise videos should be modified in the next editing step. An overview of relevant criteria for a voice therapy app, regarding design and functions, was derived from the results. CONCLUSION: This user-oriented feedback on the usability of the voice app provides the proof of concept and the basis for the further development of the Artificial intelligence-based innovative follow-up app LAOLA. In the future, it should be possible to support the treatment of all voice disorders with such an app. For the further development of the voice app, the therapeutic content and the effectiveness of the training should also be investigated.

Prophylactic slowly resorbable mesh in midline laparotomy to limit incisional hernia incidence: the prospective 'Mesh Augmented Reinforcement of Abdominal Wall Suture Line (MARS)' cohort study protocol.

Background: Incisional hernia (IH) after abdominal surgery is a frequent surgical complication. Risk factors associated with IH are midline incisions, patients with an abdominal aneurysm of the aorta, and high BMI. Preventive measures include the use of the small-bites suture technique and/or placing a prophylactic mesh for reinforcement of the midline closure. Although recommended for high-risk patients, many surgeons are still reluctant to place a prophylactic mesh due to related complications. To counter these concerns, new synthetic resorbable meshes are being developed, such as the Deternia Self-Gripping Resorbable Mesh ("investigational device"). However, the effectiveness of this mesh in IH prevention has not been proved. Methods: The Mesh Augmented Reinforcement of Abdominal Wall Suture Line (MARS) study is a European, multicentre, prospective, single-arm study. A total of 120 patients scheduled for elective midline laparotomy, and for that reason at risk of developing IH, will be recruited in ~12 sites after informed consent. The sample size was estimated based on greater than 80% power, two-sided alpha of 0.05, an expected 12 month IH rate of 8% and a predefined performance goal of 18% (10% clinical margin). Midline incisions will be closed by the small bites closure technique with a minimum 4:1 suture-to-wound length ratio and reinforced by mesh placement in the retrorectus position. The primary outcome will be IH occurrence at 12-month postoperatively, evaluated both clinically and by ultrasound. Secondary outcomes will include mesh-related and postoperative complications, surgical characteristics, IH incidence at 2 and 3 years after surgery, and quality of life. Discussion: Currently, no conclusive evidence is available for synthetic resorbable meshes in a prophylactic setting to prevent IH. The MARS study will be the first prospective cohort study to investigate resorbable synthetic meshes and small bites closure to reduce IH incidence.

The impact of resection margin distance on survival and recurrence in pancreatic ductal adenocarcinoma in a retrospective cohort analysis.

BACKGROUND: The prognostic effect of resection margin status following pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC) remains controversial, even with the implementation of standardized pathological assessment. We therefore investigated the impact of resection margin (RM) status and RM distance in curative resected PDAC on overall survival (OS), disease-free survival (DFS) and recurrence. METHOD: 108 patients were retrieved from a prospectively maintained database of a certified pancreatic cancer center. Distribution and relationships between circumferential resection margin (CRM) involvement (CRM≤1mm; CRM>1mm; CRM≥2mm) and their prognostic impact on OS and DFS were assessed using Kaplan-Meier statistics and the Log-Rank test. Multivariate logistic regression was used explain the development of a recurrence 12 months after surgery. RESULTS: 63 out of 108 patients had medial RM and 32 posterior RM involvement. There was no significant difference in OS and DFS between CRM≤1mm and CRM>1mm resections. Clearance at the medial margin of ≥2mm had an impact on OS and DFS, (RM≥2mm vs. RM<2mm: median OS 29.8 vs 16.8 months, median DFS 19.6 vs. 10.3 months). Multivariate analysis demonstrated that age, medial RM ≥2mm, lymph node status and chemotherapy were prognostic factors for OS and DFS. Posterior RM had no influence on OS or DFS. CONCLUSION: Not all RM seem to have the same impact on OS and DFS, and a clearance of 1mm for definition of a negative RM (i.e. CRM>1mm) seems not sufficient. Future studies should include more patients to stratify for potential confounders we could not account for. TRIAL REGISTRATION: This study was registered with the German Clinical Trials Registry (reference number DRKS0017425).

A virtual reality simulation of a novel way to illuminate the surgical field - A feasibility study on the use of automated lighting systems in the operating theatre.

Introduction: Surgical lighting systems have to be re-adjusted manually during surgery by the medical personnel. While some authors suggest that interaction with a surgical lighting system in the operating room might be a distractor, others support the idea that manual interaction with the surgical lighting system is a hygiene problem as pathogens might be present on the handle. In any case, it seems desirable to develop a novel approach to surgical lighting that minimizes the need for manual interaction during a surgical procedure. Methodes: We investigated the effect of manual interaction with a classical surgical lighting system and simulated a proposed novel design of a surgical lighting system in a virtual reality environment with respect to performance accuracy as well as cognitive load (measured by electroencephalographical recordings). Results: We found that manual interaction with the surgical lights has no effect on the quality of performance, yet for the price of a higher mental effort, possibly leading to faster fatigue of the medical personnel in the long run. Discussion: Our proposed novel surgical lighting system negates the need for manual interaction and leads to a performance quality comparable to the classical lighting system, yet with less mental load for the surgical personnel.

Qualitative and Economic Impact of Standardized and Digitalized Operation Room Processes in Obesity Surgery.

PURPOSE: The introduction of innovative digital solutions in healthcare lags compared to other industries but promises high potential to create value in efficiency and quality. Increasing economic pressure forces hospitals to optimize operating room (OR) processes, in which such solutions might provide additional support. MATERIALS AND METHODS: This retrospective case-control and monocentric study investigated if digitalized and standardized intraoperative surgical workflows of laparoscopic Roux-en-Y gastric bypass (LRYGB) have a significant impact on efficiency, quality, and economics. Logistic and linear regression models were used to apply propensity score matching (PSM) for efficiency and odds ratio for the quality analysis. RESULTS: The study included 49 patients per group. The results demonstrate a significant increase in efficiency and cost-effectiveness in the treatment group. Length of stay (LoS) was 1.2 days less than in the control group (5.6 vs. 4.4). The mean of total OR and skin-to-skin time increased by 3.7% (142.00 vs. 136.80) and 8.5%, respectively (93.88 vs. 85.94). The standard deviation (SD) of total OR and skin-to-skin time decreased by 7.36 min (26.86 vs. 34.22) and 8.98 min (23.20 vs. 32.18) in the treatment group. The results of the odds ratio did not provide any conclusions on quality. Overall, costs were reduced by 318 € per patient and total revenue improved by 10,073 €. CONCLUSION: The implementation of digital workflow management systems in obesity surgery improves economic efficiency. Hospital management and payors should evaluate further support in research of the digitization of the OR, followed by reimbursement to increase and facilitate the accessibility to digital support systems.

Prophylactic effect of retromuscular mesh placement during loop ileostomy closure on incisional hernia incidence-a multicentre randomised patient- and observer-blind trial (P.E.L.I.O.N trial).

BACKGROUND: Incisional hernia is a frequent complication following loop ileostomy reversal. Incisional hernias are associated with morbidity, loss of health-related quality of life and costs and warrant the investigation of prophylactic measures. Prophylactic mesh implantation at the time of surgical stoma reversal has shown to be a promising and safe method to prevent incisional hernias in this setting. However, the efficacy of this method has not yet been investigated in a large multicentre randomised-controlled trial (RCT) with adequate external validity. The P.E.L.I.O.N. trial will evaluate the efficacy of prophylactic mesh reinforcement after loop ileostomy closure in decreasing the rate of incisional hernia versus standard closure alone. METHODS: P.E.L.I.O.N. is a multicentre, patient- and observer-blind RCT. Patients undergoing loop ileostomy closure will undergo intraoperative 1:1 randomisation into either abdominal wall closure with a continuous slowly absorbable suture in small-stitch technique without mesh reinforcement (control group) or abdominal wall closure with an additional reinforcement with a retromuscular non-absorbable, macro-pore (pore size ≥ 1000 µm or effective porosity >0%) light-weight monofilament or mixed structure mesh. A total of 304 patients (152 per group) will need to be randomised in the study. Based on inclusion and exclusion criteria, 1,014 patients are expected to be screened for eligibility in order to recruit the necessary number of patients. The primary endpoint will be the frequency of incision hernias within 24 months according to the European Hernia Society definition. Secondary endpoints will be the frequency of surgical site occurrences (including surgical site infections, wound seromas and hematomas, and enterocutaneous fistulas), postoperative pain, the number of revision surgeries and health-related quality of life. Safety will be assessed by measuring postoperative complications ≥ grade 3 according to the Dindo-Clavien classification. DISCUSSION: Depending on the results of the P.E.L.I.O.N. trial, prophylactic mesh implantation could become the new standard for loop ileostomy reversal. TRIAL REGISTRATION: DRKS00027921, U1111-1273-4657.

Thyroid disease-specific quality of life questionnaires - A systematic review.

INTRODUCTION: Thyroid diseases are very common and rarely life-threatening. One of the main therapeutic goals is an improvement in quality of life, making it important to measure in clinical and research settings. The aim of this systematic review is to provide an overview of the currently available thyroid-specific quality of life questionnaires with regard to their validation quality in order to make recommendations for clinical use with a special focus on German questionnaires. METHODS: A systematic literature search was performed in Pubmed, Google Scholar and the Cochrane Library. A total of 904 studies were identified. After excluding duplicates, non-English- or German-language texts, full texts that were not freely available and studies with irrelevant content, 64 studies reporting on 16 different questionnaires were included in the analysis. RESULTS: Four questionnaires concerned benign thyroid diseases (ThyPRO, ThyPRO-39, Thy-R-HRQoL and Thy-D-QOL), six malignant thyroid diseases (THYCA-QoL, ThyCa-HRLQOL, EORTC-Thy34, MADSI-Thy, QOL-Thyroid and ThyCAT), and six endocrine orbitopathy (GO-QOL, GO-QLS, TED-QOL, STED-QOL, TAO-QoL and Ox-TED). Only five questionnaires were at least developed, if not validated, in German, and five were developed in more than two languages. CONCLUSIONS: ThyPRO and the ThyPRO-39 are the best-evaluated questionnaires for benign thyroid diseases. Alternatively, in hypothyroid patients, the adequately validated Thy-D-QoL can be used. For malignant thyroid diseases, the choice should be made individually, as all six questionnaires (THYCA-QoL, ThyCA-HRQOL, EORTC-Thy34, MDASI-Thy, QOL-Thyroid and ThyCAT) have different strengths and weaknesses. The GO-QOL is the best-validated questionnaire in endocrine orbitopathy. However, the TED-QOL is also suitable as a short-screening questionnaire for these patients.

Flexible semiparametric mode regression for time-to-event data.

The distribution of time-to-event outcomes is usually right-skewed. While for symmetric and moderately skewed data the mean and median are appropriate location measures, the mode is preferable for heavily skewed data as it better represents the center of the distribution. Mode regression has been introduced for uncensored data to model the relationship between covariates and the mode of the outcome. Starting from nonparametric kernel density based mode regression, we examine the use of inverse probability of censoring weights to extend mode regression to handle right-censored data. We add a semiparametric predictor to add further flexibility to the model and we construct a pseudo Akaike's information criterion to select the bandwidth and smoothing parameters. We use simulations to evaluate the performance of our proposed approach. We demonstrate the benefit of adding mode regression to one's toolbox for analyzing survival data on a pancreatic cancer data set from a prospectively maintained cancer registry.

Immersive Anatomy Atlas: Learning Factual Medical Knowledge in a Virtual Reality Environment.

In order to improve learning efficiency and memory retention in medical teaching, furthering active learning seems to be an effective alternative to classical teaching. One option to make active exploration of the subject matter possible is the use of virtual reality (VR) technology. The authors developed an immersive anatomy atlas which allows users to explore human anatomical structures interactively through virtual dissection. Thirty-two senior-class students from two German high schools with no prior formal medical training were separated into two groups and tasked with answering an anatomical questionnaire. One group used traditional anatomical textbooks and the other used the immersive virtual reality atlas. The time needed to answer the questions was measured. Several weeks later, the participants answered a similar questionnaire with different anatomical questions in order to test memory retention. The VR group took significantly less time to answer the questionnaire, and participants from the VR group had significantly better results over both tests. Based on the results of this study, VR learning seems to be more efficient and to have better long-term effects for the study of anatomy. The reason for that could lie in the VR environment's high immersion, and the possibility to freely and interactively explore a realistic representation of human anatomy. Immersive VR technology offers many possibilities for medical teaching and training, especially as a support for cadaver dissection courses.