Systematic review, network meta-analysis and exploratory cost-effectiveness model of randomized trials of minimally invasive techniques versus surgery for varicose veins

Background A Health Technology Assessment was conducted to evaluate the relative clinical effectiveness and cost-effectiveness of minimally invasive techniques (foam sclerotherapy (FS), endovenous laser ablation (EVLA) and radiofrequency ablation (RFA)) for managing varicose veins, in comparison with traditional surgery. Methods A systematic review of randomized clinical trials (RCTs) was undertaken to assess the effectiveness of minimally invasive techniques compared with other treatments, principally surgical stripping, in terms of recurrence of varicose veins, Venous Clinical Severity Score (VCSS), pain and quality of life. Network meta-analysis and exploratory cost-effectiveness modelling were performed. Results The literature search conducted in July 2011 identified 1453 unique citations: 31 RCTs (51 papers) satisfied the criteria for effectiveness review. Differences between treatments were negligible in terms of clinical outcomes, so the treatment with the lowest cost appears to be most cost-effective. Total FS costs were estimated to be lowest, and FS was marginally more effective than surgery. However, relative effectiveness was sensitive to the model time horizon. Threshold analysis indicated that EVLA and RFA might be considered cost-effective if their costs were similar to those for surgery. These findings are subject to various uncertainties, including the risk of bias present in the evidence base and variation in reported costs. Conclusion This assessment of currently available evidence suggests there is little to choose between surgery and the minimally invasive techniques in terms of efficacy or safety, so the relative cost of the treatments becomes one of the deciding factors. High-quality RCT evidence is needed to verify and further inform these findings

Nonlinear Advantage: Trained Networks Might Not Be As Complex as You Think

We perform an empirical study of the behaviour of deep networks when fully linearizing some of its feature channels through a sparsity prior on the overall number of nonlinear units in the network. In experiments on image classification and machine translation tasks, we investigate how much we can simplify the network function towards linearity before performance collapses. First, we observe a significant performance gap when reducing nonlinearity in the network function early on as opposed to late in training, in-line with recent observations on the time-evolution of the data-dependent NTK. Second, we find that after training, we are able to linearize a significant number of nonlinear units while maintaining a high performance, indicating that much of a network's expressivity remains unused but helps gradient descent in early stages of training. To characterize the depth of the resulting partially linearized network, we introduce a measure called average path length, representing the average number of active nonlinearities encountered along a path in the network graph. Under sparsity pressure, we find that the remaining nonlinear units organize into distinct structures, forming core-networks of near constant effective depth and width, which in turn depend on task difficulty

Das Potenzial nichtstaatlichen Gebietsschutzes in Deutschland

Um den globalen Biodiversitätsverlust aufzuhalten, müssen die weltweit bestehenden Schutzgebietssysteme ergänzt und ertüchtigt werden. Die Biodiversitätsstrategie 2030 der Europäischen Union (EU) hat zum Ziel, mindestens 30 % der Land- und Meeresfläche in der EU bis 2030 unter Schutz zu stellen und jeweils mindestens 10 % dieser Flächen streng zu schützen. Deutschland hat diese Ziele auf nationaler Ebene noch nicht erreicht. Bei der Ergänzung des deutschen Schutzgebietssystems könnten freiwillige Formen des Gebietsschutzes durch nichtstaatliche Akteure einbezogen und so die Kohärenz und Konnektivität staatlicher Schutzgebiete verbessert werden. Im Beitrag werden zwei Arten von Gebietsschutz durch nichtstaatliche Akteure behandelt: Gebietsschutz in privaten Schutzgebieten (engl. privately protected areas − PPAs) und Gebietsschutz durch andere wirksame flächenbezogene Naturschutzmaßnahmen (engl. other effective area-based conservation measures – OECMs). Obwohl das deutsche Naturschutzrecht keine eigenständige Kategorie für nichtstaatlichen Gebietsschutz vorsieht, zeigen unsere Schätzungen, dass OECMs durchaus einen Beitrag zu den Gebietsschutzzielen in Deutschland leisten können. Der vorliegende Beitrag macht Vorschläge, welche Gebiete dafür infrage kämen

Heat conduction from the exceedingly hot fiber tip contributes to the endovenous laser ablation of varicose veins

Lower-extremity venous insufficiency is a common condition, associated with considerable health care costs. Endovenous laser ablation is increasingly used as therapy, but its mechanism of action is insufficiently understood. Here, direct absorption of the laser light, collapsing steam bubbles and direct fiber-wall contact have all been mentioned as contributing mechanisms. Because fiber tips have reported temperatures of 800-1,300°C during endovenous laser ablation, we sought to assess whether heat conduction from the hot tip could cause irreversible thermal injury to the venous wall. We approximated the hot fiber tip as a sphere with diameter equal to the fiber diameter, having a steady state temperature of 800°C or 1,000°C. We computed venous wall temperatures due to heat conduction from this hot sphere, varying the pullback velocity of the fiber and the diameter of the vein. Venous wall temperatures corresponding to irreversible injury resulted for a 3 mm diameter vein and pullback velocities <3 mm/s but not for 5 mm and 1 mm/s. The highest wall temperature corresponded to the position on the wall closest to the fiber tip, hence it moves longitudinally in parallel with the moving fiber tip. We concluded that heat conduction from the hot fiber tip is a contributing mechanism in endovenous laser ablation

Inhibition abilities and functional brain connectivity in school-aged term-born and preterm-born children

Background Inhibition abilities are known to have impact on self-regulation, behavior, and academic success, and they are frequently impaired in children born preterm. We investigated the possible contributions of resting-state functional brain connectivity to inhibition following preterm birth. Methods Forty-four preterm and 59 term-born participants aged 8–13 years were administered two inhibition tasks and resting-state functional MRI was performed. Functional connectivity (FC) networks were compared between groups using network-based statistics. Associations of FCNs and inhibition abilities were investigated through multivariate linear regression models accounting for the interaction between birth status and inhibition. Results NBS revealed weaker FC in children born preterm compared to term-born peers in connections between motor and supplementary motor regions, frontal lobe, precuneus, and insula. Irrespective of birth status, connections between the cerebellum, frontal, and occipital lobes and inter-lobar, subcortical, intra-hemispheric long-range connections were positively correlated with one of the two inhibition tasks. Conclusions Preterm birth results in long-term alterations of FC at network level but these FCN alterations do not specifically account for inhibition problems in children born very preterm. Impact Irrespective of birth status, significant associations were found between the subdomain of response inhibition and functional connectivity in some subnetworks. A group comparisons of functional brain connectivity measured by rsfMRI in school-aged children born very preterm and at term. The investigation of network-level functional connectivity at rest does not appear adequate to explain differences in inhibition abilities between children born very preterm and at term, hence other imaging techniques might be more suited to explore the underlying neural mechanisms of inhibition abilities in school-aged children born very preterm

Neuromonitoring, neuroimaging, and neurodevelopmental follow-up practices in neonatal congenital heart disease: a European survey

BACKGROUND Brain injury and neurodevelopmental impairment remain a concern in children with complex congenital heart disease (CHD). A practice guideline on neuromonitoring, neuroimaging, and neurodevelopmental follow-up in CHD patients undergoing cardiopulmonary bypass surgery is lacking. The aim of this survey was to systematically evaluate the current practice in centers across Europe. METHODS An online-based structured survey was sent to pediatric cardiac surgical centers across Europe between April 2019 and June 2020. Results were summarized by descriptive statistics. RESULTS Valid responses were received by 25 European centers, of which 23 completed the questionnaire to the last page. Near-infrared spectroscopy was the most commonly used neuromonitoring modality used in 64, 80, and 72% preoperatively, intraoperatively, and postoperatively, respectively. Neuroimaging was most commonly performed by means of cranial ultrasound in 96 and 84% preoperatively and postoperatively, respectively. Magnetic resonance imaging was obtained in 72 and 44% preoperatively and postoperatively, respectively, but was predominantly reserved for clinically symptomatic patients (preoperatively 67%, postoperatively 64%). Neurodevelopmental follow-up was implemented in 40% of centers and planned in 24%. CONCLUSIONS Heterogeneity in perioperative neuromonitoring and neuroimaging practice in CHD in centers across Europe is large. The need for neurodevelopmental follow-up has been recognized. A clear practice guideline is urgently needed. IMPACT There is large heterogeneity in neuromonitoring, neuroimaging, and neurodevelopmental follow-up practices among European centers caring for neonates with complex congenital heart disease. This study provides a systematic evaluation of the current neuromonitoring, neuroimaging, and neurodevelopmental follow-up practice in Europe. The results of this survey may serve as the basis for developing a clear practice guideline that could help to early detect and prevent neurological and neurodevelopmental sequelae in neonates with complex congenital heart disease

Early High-Dose Erythropoietin and Cognitive Functions of School-Aged Children Born Very Preterm

Importance: Children born very preterm are at risk for long-term neurodevelopmental sequelae. Prophylactic high-dose recombinant human erythropoietin (rhEpo) shortly after birth has not been shown to improve cognitive, motor, and behavioral development at 2 and 5 years. Objective: To investigate whether early high-dose rhEpo is associated with better executive functions and processing speed—late-maturing cognitive functions—in school-aged children born very preterm. Design, Setting, and Participants: This single-center cohort study was a prospective, observational follow-up study of a multicenter neonatal clinical trial; 365 children born very preterm (mean gestational age, 29.3 weeks [range, 26.0-31.9 weeks]) who had been enrolled in the Swiss EPO Neuroprotection Trial at birth between 2005 and 2012, and who were included in the primary outcome analyses at 2 years, were eligible to be recruited for the EpoKids study between 2017 and 2021 when they were at school age. Term-born children were additionally recruited and included in a control group. Data were analyzed between May and September 2022. Exposure: Administration of rhEpo (3000 IU/kg) or placebo (saline, 0.9%) intravenously 3 times within the first 2 days of life as part of the Swiss EPO Neuroprotection Trial. Main Outcome and Measures: A comprehensive neuropsychological test battery assessed executive functions and processing speed, and parents reported on their child’s executive functions in everyday life to test the hypothesis that early high-dose rhEpo administration is associated with better cognitive outcomes at school age. Results: In the EpoKids study, 214 children born very preterm (58.6% of 365 children in eligible cohort) were assessed at a mean age of 10.4 years (range, 6.9-13.4 years); 117 (54.7%) were boys. There was no evidence that the 117 children who had received rhEpo differed from the 97 children who had received placebo in any of the 15 executive function and processing speed tests, nor in parent-rated executive functions (estimates ranged from −0.138 to 0.084, all 95% CIs included 0). Irrespective of rhEpo or placebo allocation, children born very preterm scored lower on 11 of 15 executive function and processing speed tests than term-born peers (estimates ranged from 0.112 to 0.255, 95% CIs did not include 0). Conclusion and Relevance: This study found no evidence for a positive association between prophylactic early high-dose rhEpo administration and long-term neurodevelopmental outcomes after very preterm birth. These results suggest that a comprehensive approach, including pharmacological and nonpharmacological prevention and intervention strategies, is needed to support these children’s neurodevelopmental outcome

Enhancing educational and vocational recovery in adolescents and young adults with early psychosis through Supported Employment and Education (SEEearly): study protocol for a multicenter randomized controlled trial

BackgroundPsychotic disorders often develop a chronic course with devastating consequences for individuals, families, and societies. Early intervention programs for people in the first 5 years after the initial psychotic episode (early psychosis) can significantly improve the outcome and are therefore strongly recommended in national and international guidelines. However, most early intervention programs still focus on improving symptoms and relapse prevention, rather than targeting educational and vocational recovery. The aim of the present study is to explore the effects of Supported Employment and Education (SEE) following the Individual Placement and Support (IPS) model in people with early psychosis.MethodsThe SEEearly trial compares treatment as usual (TAU) plus SEE to TAU alone in outpatient psychiatric settings. The study is a six-site, two-arm, single-blinded, superiority randomized controlled trial (RCT). Participants are randomly assigned (1:1) to the intervention or control group. Aiming to recruit 184 participants, with an assumed drop-out rate of 22%, we will be able to detect a 24% difference in the main outcome of employment/education with 90% power. We make assessments at baseline and at 6- and 12-month follow-ups. Outcome data on employment/education, medication, and current psychiatric treatment is obtained monthly through phone based short assessments. The primary outcome is steady participation for at least 50% of the 12-month follow-up in competitive employment and/or mainstream education. Secondary employment outcomes capture length of employment/education, time to first employment/education, monthly wages/educational attainment, and social return on investment (SROI). Secondary non-employment outcomes include subjective quality of life, psychopathology, substance use, relapse, hospitalization, and functional impairment. To be eligible, participants must be between 16 and 35 years, fulfill diagnostic criteria for early psychosis, and be interested in competitive employment and/or mainstream education.DiscussionIn SEEearly, we hypothesize that participants with psychosis, who receive TAU plus SEE, present with better primary and secondary outcomes than participants, who receive TAU alone. Positive results of this study will justify SEE as an evidence-based strategy for clinical routine treatment in people with early psychosis