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Aim:
The most suitable method for assessment of response to peptide receptor radionuclide therapy (PRRT) of neuroendocrine tumors (NET) is still under debate. In this study we aimed to compare size (RECIST 1.1), density (Choi), Standardized Uptake Value (SUV) and a newly defined ZP combined parameter derived from Somatostatin Receptor (SSR) PET/CT for prediction of both response to PRRT and overall survival (OS).
Material and Methods:
Thirty-four NET patients with progressive disease (F:M 23:11; mean age 61.2 y; SD ± 12) treated with PRRT using either Lu-177 DOTATOC or Lu-177 DOTATATE and imaged with Ga-68 SSR PET/CT approximately 10–12 weeks prior to and after each treatment cycle were retrospectively analyzed. Median duration of follow-up after the first cycle was 63.9 months (range 6.2–86.2). A total of 77 lesions (2–8 per patient) were analyzed. Response assessment was performed according to RECIST 1.1, Choi and modified EORTC (MORE) criteria. In addition, a new parameter named ZP, the product of Hounsfield unit (HU) and SUVmean (Standard Uptake Value) of a tumor lesion, was tested. Further, SUV values (max and mean) of the tumor were normalized to SUV of normal liver parenchyma. Tumor response was defined as CR, PR, or SD. Gold standard for comparison of baseline parameters for prediction of response of individual target lesions to PRRT was change in size of lesions according to RECIST 1.1. For prediction of overall survival, the response after the first and second PRRT were tested.
Results:
Based on RECIST 1.1, Choi, MORE, and ZP, 85.3%, 64.7%, 61.8%, and 70.6% achieved a response whereas 14.7%, 35.3%, 38.2%, and 29.4% demonstrated PD (progressive disease), respectively. Baseline ZP and ZPnormalized were found to be the only parameters predictive of lesion progression after three PRRT cycles (AUC ZP 0.753; 95% CI 0.6–0.9, p 0.037; AUC ZPnormalized 0.766; 95% CI 0.6–0.9; p 0.029). Based on a cut-off-value of 1201, ZP achieved a sensitivity of 86% and a specificity of 67%, while ZPnormalized reached a sensitivity of 86% and a specificity of 76% at a cut-off-value of 198. Median OS in the total cohort was not reached. In univariate analysis amongst all parameters, only patients having progressive disease according to MORE after the second cycle of PRRT were found to have significantly shorter overall survival (median OS in objective responders not reached, in PD 29.2 months; p 0.015). Patients progressive after two cycles of PRRT according to ZP had shorter OS compared to those responding (median OS for responders not reached, for PD 47.2 months, p 0.066).
Conclusions:
In this explorative study, we showed that Choi, RECIST 1.1, and SUVmax-based response evaluation varied significantly from each other. Only patients showing progressive disease after two PRRT cycles according to MORE criteria had a worse prognosis while baseline ZP and
ZPnormalized performed best in predicting lesion progression after three cycles of PRRT.
Methods for standard meta-analysis of diagnostic test accuracy studies are well established and understood. For the more complex case in which studies report test accuracy across multiple thresholds, several approaches have recently been proposed. These are based on similar ideas, but make different assumptions. In this article, we apply four different approaches to data from a recent systematic review in the area of nephrology and compare the results. The four approaches use: a linear mixed effects model, a Bayesian multinomial random effects model, a time-to-event model and a nonparametric model, respectively. In the case study data, the accuracy of neutrophil gelatinase-associated lipocalin for the diagnosis of acute kidney injury was assessed in different scenarios, with sensitivity and specificity estimates available for three thresholds in each primary study. All approaches led to plausible and mostly similar summary results. However, we found considerable differences in results for some scenarios, for example, differences in the area under the receiver operating characteristic curve (AUC) of up to 0.13. The Bayesian approach tended to lead to the highest values of the AUC, and the nonparametric approach tended to produce the lowest values across the different scenarios. Though we recommend using these approaches, our findings motivate the need for a simulation study to explore optimal choice of method in various scenarios.
Für Fachangestellte für Medien- und Informationsdienste (FaMIs) ist berufsbegleitendes Studieren eine erfolgreiche Maßnahme zur Höherqualifizierung. Bibliotheken können ihrerseits im Rahmen der Personalentwicklung mit der Unterstützung von studierenden Mitarbeitenden dem Fachkräftemangel entgegenwirken. Der Beitrag stellt die Personalentwicklungsmaßnahme am Beispiel des Bachelor-Studiengangs „Informationsmanagement – berufsbegleitend“ der Hochschule Hannover vor. Es werden Informationen aus der Beratungspraxis dargelegt und die mögliche Unterstützung durch die entsendenden Bibliotheken aufgezeigt.
Within the HiGHmeducation consortium various online learning modules shall be developed by members of the consortium to address the increasing need for skilled professionals in a networked and digitalized healthcare system. Transferability of these modules to other locations is one main objective for the design of online learning modules. Thus, a didactical framework for online learning modules was developed. To ensure feasibility of the framework, the participating universities were analyzed concerning availability of e-learning support structures and infrastructures including learning management systems (LMS). The analysis especially focuses on the various LMS learning tools and their suitability for the framework. The framework is the basis for 12 HiGHmeducation online learning modules of which a part has firstly been conducted in winter 2019/20 and leads to a comparable structure of the modules.
Library of Congress Subject Headings (LCSH) are popular for indexing library records. We studied the possibility of assigning LCSH automatically by training classifiers for terms used frequently in a large collection of abstracts of the literature on hand and by extracting headings from those abstracts. The resulting classifiers reach an acceptable level of precision, but fail in terms of recall partly because we could only train classifiers for a small number of LCSH. Extraction, i.e., the matching of headings in the text, produces better recall but extremely low precision. We found that combining both methods leads to a significant improvement of recall and a slight improvement of F1 score with only a small decrease in precision.
We compare the effect of different segmentation strategies for passage retrieval of user generated internet video. We consider retrieval of passages for rather abstract and complex queries that go beyond finding a certain object or constellation of objects in the visual channel. Hence the retrieval methods have to rely heavily on the recognized speech. Passage retrieval has mainly been studied to improve document retrieval and to enable question answering. In these domains best results were obtained using passages defined by the paragraph structure of the source documents or by using arbitrary overlapping passages. For the retrieval of relevant passages in a video no author defined paragraph structure is available. We compare retrieval results from 5 different types of segments: segments defined by shot boundaries, prosodic segments, fixed length segments, a sliding window and semantically coherent segments based on speech transcripts. We evaluated the methods on the corpus of the MediaEval 2011 Rich Speech Retrieval task. Our main conclusions are (1) that fixed length and coherent segments are clearly superior to segments based on speaker turns or shot boundaries; (2) that the retrieval results highly depend on the right choice for the segment length; and (3) that results using the segmentation into semantically coherent parts depend much less on the segment length. Especially, the quality of fixed length and sliding window segmentation drops fast when the segment length increases, while quality of the semantically coherent segments is much more stable. Thus, if coherent segments are defined, longer segments can be used and consequently fewer segments have to be considered at retrieval time.
During the intraoperative radiograph generation process with mobile image intensifier systems (C-arm) most of the radiation exposure for patient, surgeon and operation room personal is caused by scattered radiation. The intensity and propagation of scattered radiation depend on different parameters, e.g. the intensity of the primary radiation, and the positioning of the mobile image intensifier. Exposure through scattered radiation can be minimized when all these parameters are adjusted correctly. Because radiation is potentially dangerous and could not be perceived by any human sense the current education on correct adjustment of a C-arm is designed very theoretical. This paper presents an approach of scattered radiation calculation and visualization embedded in a computer based training system for mobile image intensifier systems called virtX. With the help of this extension the virtX training system should enrich the current radiation protection training with visual and practical training aspects.
Hintergrund und Fragestellung: Die durch röntgentechnische Diagnoseverfahren in der Medizin entstehende Strahlenbelastung für Patient und Personal soll laut Strahlenschutzverordnung so gering wie möglich gehalten werden. Um dieses zu erreichen ist ein professioneller und bedachter Umgang mit den Röntgengeräten unabdingbar. Dieses Verhalten kann derzeit jedoch nur theoretisch vermittelt werden, da sich ein Üben mit realer Strahlung von selbst verbietet. Daher stellt sich die Frage wie man die Strahlenschutzausbildung durch eine verbesserte Vermittlung der komplexen Thematik unterstützen kann. Methoden: Das CBT-System (Computer Based Training) virtX, welches das Erlernen der korrekten Handhabung mobiler Röntgengeräte unterstützt, wurde um Aspekte aus dem Bereich des Strahlenschutzes erweitert. Es wurde eine prototypische Visualisierung der entstehenden Streustrahlung sowie die Darstellung des Nutzstrahlenganges integriert. Des Weiteren wurde die Berechnung und Anzeige der virtuellen Einfallsdosis für das durchstrahlte Volumen sowie für den Bereich des Bildverstärkers hinzugefügt. Für die Berechnung und Visualisierung all dieser Komponenten werden die in virtX parametrisierbaren C-Bogen-Einstellungen, z.B. Stellung der Blenden, Positionierung des Röntgengerätes zum durchstrahlten Volumen und Strahlenintensität, herangezogen. Das so erweiterte System wurde auf einem dreitägigen Kurs für OP-Personal mit über 120 Teilnehmern eingesetzt und auf der Basis von Fragebögen evaluiert. Ergebnisse: Von den Teilnehmern gaben 55 einen ausgefüllten Evaluations-Fragebogen ab (Responserate 82%). Das Durchschnittsalter der 39 weiblichen und 15 männlichen Teilnehmer (einer o.A.) lag bei 33±8 Jahren, die Berufserfahrung bei 9,37±7 Jahren. Die Erfahrung mit dem C-Bogen wurde von einem Teilnehmer (2%) mit „Keine oder bisher nur Einführung erhalten“, von acht Teilnehmern (14%) mit „bediene einen C-Bogen gelegentlich“ und von 46 (84%) mit „bediene einen C-Bogen regelmäßig“ angegeben. 45 (92%) der Teilnehmer gaben an, durch die Visualisierung der Streustrahlung etwas Neues zur Vermeidung unnötiger Strahlenbelastung dazugelernt zu haben. Schlussfolgerung: Trotz einer bislang nur prototypischen Visualisierung der Streustrahlung können mit virtX zentrale Aspekte und Verhaltensweisen zur Vermeidung unnötiger Strahlenbelastung erfolgreich vermittelt werden und so Lücken der traditionellen Strahlenschutzausbildung geschlossen werden.
Background:
Promoting patient and occupational safety are two key challenges for hospitals. When aiming to improve these two outcomes synergistically, psychosocial working conditions, leadership by hospital management and supervisors, and perceptions of patient and occupational safety climate have to be considered. Recent studies have shown that these key topics are interrelated and form a critical foundation for promoting patient and occupational safety in hospitals. So far, these topics have mainly been studied independently from each other. The present study investigated hospital staffs’ perceptions of four different topics: (1) psychosocial working conditions, (2) leadership, (3) patient safety climate, and (4) occupational safety climate. We present results from a survey in two German university hospitals aiming to detect differences between nurses and physicians.
Methods:
We performed a cross-sectional study using a standardized paper-based questionnaire. The survey was conducted with nurses and physicians to assess the four topics. The instruments mainly consisted of scales of the German version of the COPSOQ (Copenhagen Psychosocial Questionnaire), one scale of the Copenhagen Burnout Inventory (CBI), scales to assess leadership and transformational leadership, scales to assess patient safety climate using the Hospital Survey on Patient Safety Culture (HSPSC), and analogous items to assess occupational safety climate.
Results:
A total of 995 completed questionnaires out of 2512 distributed questionnaires were returned anonymously. The overall response rate was 39.6%. The sample consisted of 381 physicians and 567 nurses. We found various differences with regard to the four topics. In most of the COPSOQ and the HSPSC-scales, physicians rated psychosocial working conditions and patient safety climate more positively than nurses. With regard to occupational safety, nurses
indicated higher occupational risks than physicians.
Conclusions:
The WorkSafeMed study combined the assessment of the four topics psychosocial working conditions, leadership, patient safety climate, and occupational safety climate in hospitals. Looking at the four topics provides an overview of where improvements in hospitals may be needed for nurses and physicians. Based on these results,
improvements in working conditions, patient safety climate, and occupational safety climate are required for health care professionals in German university hospitals – especially for nurses.