29 research outputs found

    Augmented reality visualization in brain lesions: a prospective randomized controlled evaluation of its potential and current limitations in navigated microneurosurgery

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    Background: Augmented reality (AR) has the potential to support complex neurosurgical interventions by including visual information seamlessly. This study examines intraoperative visualization parameters and clinical impact of AR in brain tumor surgery. Methods: Fifty-five intracranial lesions, operated either with AR-navigated microscope (n = 39) or conventional neuronavigation (n = 16) after randomization, have been included prospectively. Surgical resection time, duration/type/mode of AR, displayed objects (n, type), pointer-based navigation checks (n), usability of control, quality indicators, and overall surgical usefulness of AR have been assessed. Results: AR display has been used in 44.4% of resection time. Predominant AR type was navigation view (75.7%), followed by target volumes (20.1%). Predominant AR mode was picture-in-picture (PiP) (72.5%), followed by 23.3% overlay display. In 43.6% of cases, vision of important anatomical structures has been partially or entirely blocked by AR information. A total of 7.7% of cases used MRI navigation only, 30.8% used one, 23.1% used two, and 38.5% used three or more object segmentations in AR navigation. A total of 66.7% of surgeons found AR visualization helpful in the individual surgical case. AR depth information and accuracy have been rated acceptable (median 3.0 vs. median 5.0 in conventional neuronavigation). The mean utilization of the navigation pointer was 2.6 x /resection hour (AR) vs. 9.7 x /resection hour (neuronavigation); navigation effort was significantly reduced in AR (P < 0.001). Conclusions: The main benefit of HUD-based AR visualization in brain tumor surgery is the integrated continuous display allowing for pointer-less navigation. Navigation view (PiP) provides the highest usability while blocking the operative field less frequently. Visualization quality will benefit from improvements in registration accuracy and depth impression

    Clinical implementation of a 3D4K-exoscope (Orbeye) in microneurosurgery

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    Exoscopic surgery promises alleviation of physical strain, improved intraoperative visualization and facilitation of the clinical workflow. In this prospective observational study, we investigate the clinical usability of a novel 3D4K-exoscope in routine neurosurgical interventions. Questionnaires on the use of the exoscope were carried out. Exemplary cases were additionally video-documented. All participating neurosurgeons (n = 10) received initial device training. Changing to a conventional microscope was possible at all times. A linear mixed model was used to analyse the impact of time on the switchover rate. For further analysis, we dichotomized the surgeons in a frequent (n = 1) and an infrequent (n = 9) user group. A one-sample Wilcoxon signed rank test was used to evaluate, if the number of surgeries differed between the two groups. Thirty-nine operations were included. No intraoperative complications occurred. In 69.2% of the procedures, the surgeon switched to the conventional microscope. While during the first half of the study the conversion rate was 90%, it decreased to 52.6% in the second half (p = 0.003). The number of interventions between the frequent and the infrequent user group differed significantly (p = 0.007). Main reasons for switching to ocular-based surgery were impaired hand-eye coordination and poor depth perception. The exoscope investigated in this study can be easily integrated in established neurosurgical workflows. Surgical ergonomics improved compared to standard microsurgical setups. Excellent image quality and precise control of the camera added to overall user satisfaction. For experienced surgeons, the incentive to switch from ocular-based to exoscopic surgery greatly varies

    EEG Data Quality: Determinants and Impact in a Multicenter Study of Children, Adolescents, and Adults with Attention-Deficit/Hyperactivity Disorder (ADHD)

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    Electroencephalography (EEG) represents a widely established method for assessing altered and typically developing brain function. However, systematic studies on EEG data quality, its correlates, and consequences are scarce. To address this research gap, the current study focused on the percentage of artifact-free segments after standard EEG pre-processing as a data quality index. We analyzed participant-related and methodological influences, and validity by replicating landmark EEG effects. Further, effects of data quality on spectral power analyses beyond participant-related characteristics were explored. EEG data from a multicenter ADHD-cohort (age range 6 to 45 years), and a non-ADHD school-age control group were analyzed (ntotal = 305). Resting-state data during eyes open, and eyes closed conditions, and task-related data during a cued Continuous Performance Task (CPT) were collected. After pre-processing, general linear models, and stepwise regression models were fitted to the data. We found that EEG data quality was strongly related to demographic characteristics, but not to methodological factors. We were able to replicate maturational, task, and ADHD effects reported in the EEG literature, establishing a link with EEG-landmark effects. Furthermore, we showed that poor data quality significantly increases spectral power beyond effects of maturation and symptom severity. Taken together, the current results indicate that with a careful design and systematic quality control, informative large-scale multicenter trials characterizing neurophysiological mechanisms in neurodevelopmental disorders across the lifespan are feasible. Nevertheless, results are restricted to the limitations reported. Future work will clarify predictive value

    Erneuerbare Energien in der Raumplanung. Ein Hindernislauf mit TĂĽcken.

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    Die Energiewende stellt die Raumplanung vor große Herausforderungen. Insbesondere die Plannung und der Bau von Anlagen zur Gewinnung erneuerbarer Energien sind immer wieder hoch umstritten und selten einfach umzusetzen. Der Sammenband präsentiert mehrere Seminararbeiten, die unterschiedliche Aspekte zum Thema erörtern und viele Beispiele aus der Praxis darstellen

    On the effects of action on visual perception & How new movement types are learned

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    Perception can induce effects on action. Perception of others´ actions can thus influence our own actions. However, research on how action can shape perception is sparse. In this thesis, the effects of (i) motor learning and (ii) simple movements, can influence visual perception. Furthermore, the issue of motor learning is addressed; how can new movement types be learned and do active and passively guided motor training lead to differences in successful acquisition of a new movement

    Advancing sustainability through digital servitization: An exploratory study in the maritime shipping industry

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    Global businesses are transforming towards capturing more value from services, a business model transition called servitization. Digital servitization can help create and maintain a competitive advantage, as well as offering opportunities to tackle major challenges related to environmental pressures and rapidly changing market conditions. This study aims to bridge the gap between the theory of digital servitization and its implementation in the maritime shipping sector. This paper presents a multi-case study that explores the status, perceived challenges, and enablers for the adoption of digital servitization. Empirical data were collected from interviews with 13 companies and analyzed using the PESTEL and DPSIR frameworks. The results are presented across three categories based on the PESTEL framework: organizational context, global priorities, and sustainability. This study contributes to theory by providing empirical insights from the status of digital servitization in the maritime shipping industry. Also, it identifies challenges and needs that can support the transition towards digital servitization and the development of more sustainable solutions. Future research avenues are suggested to advance digital servitization in other industrial sectors.Validerad;2024;NivĂĄ 2;2024-01-22 (joosat);Full text license: CC BY</p

    Der Durchlauchtigsten Fürstin und Frau Anna Amalia verwittbeten Herzogin zu Sachsen, Jülich, Cleve und Berg, ... ihrer gnädigsten Fürstin suchten an Dero ... Geburtstage welcher den 24sten Weinmonate ... eintrat ihre unterthänigste Ehrfurcht an den Tag zu legen die sämtlichen Gymnasiasten der ersten Ordnung

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    DER DURCHLAUCHTIGSTEN FÜRSTIN UND FRAU ANNA AMALIA VERWITTBETEN HERZOGIN ZU SACHSEN, JÜLICH, CLEVE UND BERG, ... IHRER GNÄDIGSTEN FÜRSTIN SUCHTEN AN DERO ... GEBURTSTAGE WELCHER DEN 24STEN WEINMONATE ... EINTRAT IHRE UNTERTHÄNIGSTE EHRFURCHT AN DEN TAG ZU LEGEN DIE SÄMTLICHEN GYMNASIASTEN DER ERSTEN ORDNUNG Der Durchlauchtigsten Fürstin und Frau Anna Amalia verwittbeten Herzogin zu Sachsen, Jülich, Cleve und Berg, ... ihrer gnädigsten Fürstin suchten an Dero ... Geburtstage welcher den 24sten Weinmonate ... eintrat ihre unterthänigste Ehrfurcht an den Tag zu legen die sämtlichen Gymnasiasten der ersten Ordnung ([1]
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