1,720,995 research outputs found
Non-robotized frameless stereotactic magnetic resonance guided laser interstitial thermal therapy for hypothalamic hamartoma: preliminary results of 2 cases and review of the literature
Background: Various strategies have been proposed for the treatment of gelastic seizures due to hypothalamic hamartomas (HH), advancing from surgical removal techniques toward functional disconnection strategies. One of the most recent procedure is the Magnetic Resonance guided Laser Interstitial Thermal Therapy (MRg-LITT), which has progressively proved to be a safe and effective technique for hamartomas ablation. In this paper, the authors' preliminary experience with the first two patients treated with this technique in Italy is presented, in order to underline the feasibility of a pure non robotized frameless technique (FS MRg-LITT) while confirming the procedure effectiveness on seizure control. Methods: Patients undergoing FS MRg-LITT for the treatment of HH related gelastic seizures since January 2020 were included. A two steps procedure was performed by using the neuronavigation system to define the entry point, the trajectories and to assess the accuracy. Visualase Laser Ablation System was then used for the MR guided ablation of the HH. A multidisciplinary (neurosurgeons, epileptologist, neuroradiologist) institutional board evaluated the patients both in the perioperative period and during follow up. Results: A total number of 2 pediatric patients were described. The mean operative time resulted to be 6 hours while the mean accuracy was 0.4 mm. No peri-operative complications were reported. The mean length of stay was 4 days. Lastly, at 1-year follow up both patients resulted to be seizure free and endocrinological functions were preserved. Conclusions: FS MRg-LITT for the treatment of HH-related epilepsy could represent an effective technique, being able to guarantee adequate level of accuracy and potentially extending the accessibility of MRg-LITT by lowering its costs and simplifying the overall procedure
Morphometric and radiomorphometric study of the correlation between the foramen magnum region and the anterior and posterolateral approaches to ventral intradural lesions
AIM: To identify the range of dimensional morphometric variability correlated to the basilar and condylar part of the occipital bone, which may affect the choice of approach to ventral intradural foramen magnum (FM) lesions. MATERIAL and METHODS: In total, 25 dry skulls and 50 head computed tomography (CT) scan results have been assessed in detail, focusing on the FM, occipital condyles, jugular tubercles (JT), and hypoglossal canals (HC). A morphometric analysis has been carried out using linear and angular measurements to estimate the range of the dimensional variability of these structures. Data were presented as mean ± standard deviation, ranges, and interquartile range on a boxplot. The sagittal intercondylar angle (SICA) and anterior condylar angle (ACA) have been found to be important in estimating the axial orientation of the condyles, whereas the JT-HC interline ratio has indicated the prominence of the tubercles. RESULTS: The SICA and ACA have exhibited high variability. The average JT-HC interline ratio was 0.8. Wider SICA-ACA and higher JT-HC interline ratio make the posterolateral approach advantageous. An anterior medial or far-medial endoscopic route is indicated in opposite conditions. In this study, two illustrative cases have been reported. CONCLUSION: A cautious preoperative morphometric evaluation of the FM region must be considered prior to using tailored and safe anterior endoscopic and posterolateral approaches to ventral intradural lesions to identify the advantages of a certain corridor as much as possible, thereby minimizing the risk of complications
Going Beyond Counting First Authors in Author Co-citation Analysis
The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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