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Caractéristiques cliniques, traitement et évolution chez les patients ayant présenté une rupture d’un anévrysme de l’artère cérébelleuse postéroinferieure
No full textLes anévrismes de l'artère cérébelleuse postérieure inférieure (PICA) sont relativement rares, représentant environ 0,5 à 3% de tous les anévrismes intracrâniens.
La majorité des patients présentent une hémorragie sous-arachnoïdienne (HSA). La gestion et le traitement de ces lésions sont difficiles en raison de l'emplacement de la PICA à proximité du tronc cérébral et des nerfs crâniens inférieurs et de la présence de vaisseaux perforants qui fournissent le tronc cérébral.
Bien que les données publiées soient contradictoires, les évidences disponibles en littérature semblent suggérer que les patients avec un anévrisme rompu de la PICA présentent un moins bon pronostic que celui d'un anévrisme rompu d'une localisation différente. Ce phénomène laisse suspecter que cela est secondaire aux caractéristiques anatomiques et fonctionnelles particulières de ces lésions.
Afin de pouvoir analyser la présentation clinique, schéma de traitement et évolution neurologique des patients présentant des anévrismes rompus de la PICA par rapport à d'autres anévrismes rompus de la circulation postérieure, nous avons effectué une analyse rétrospective des données anonymisées de 264 patients ayant présenté une hémorragie sous-arachnoïdienne secondaire à la rupture d'un anévrysme de la circulation postérieure . Les données ont été extrapolées du registre suisse SOS, qui fait partie d'une étude de cohorte nationale sur l'hémorragie sous-arachnoïdienne d'origine anévrysmale.
74 anévrysmes de la PICA représentaient 28% de la série; les caractéristiques cliniques et radiologiques à l'admission étaient comparables entre le groupe PICA et le groupe non-PICA. Le traitement chirurgical a été réalisé chez 28% des patients du groupe PICA et chez 4,8% des patients du groupe non PICA Aucune différence statistiquement significative n'a été trouvée entre les deux groupes en termes de complications après traitement. Une hydrocéphalie nécessitant un shunt définitif était nécessaire chez 21,6% des patients PICA (p = 0,6) ; un déficit d'un nerf crânien était présent en moyenne en un quart des patients dans le groupe PICA et non-PICA sans différence statistique (p = 0,3). Un outcome plus favorable (66,2%) a été rapporté dans le groupe PICA à la sortie (p <0,05) mais cette différence s'est estompée au fil du temps avec un outcome neurologique similaire à un an de suivi (p = 0,09) entre les deux groupes. L'estimation de Kaplan Meyer n'a montré aucune différence significative dans le taux de mortalité entre les deux groupes (p
= 0,08).
Nos résultats montrent que les anévrismes rompus de la PICA présentent une issue favorable dans plus des 2/3 des cas à 1 an après le traitement, sans différence significative avec les autres localisations de la circulation postérieure. L'occlusion chirurgicale était la première option de traitement chez 28% des patients présentant des anévrismes rompus de la PICA, suggérant ainsi que, malgré le progrès du traitement endovasculaire, la chirurgie représente toujours une alternative de traitement valable. Nos résultats soutiennent la nécessité de maintenir les compétences microchirurgicales pour le traitement des anévrismes rompus de la PICA dans les centres neurovasculaires de référence.
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Background and purpose Aneurysms of the poste1ior inferior cerebellar aite1y (PICA) are relatively uncommon and evidence is sparse about patients presenting with ruptured PICA anewysms. We petfonned an analysis of the Swiss SOS national registJ.y to desctibe clinical presentation, treatment pattern, and neurological outcome of patients with rnptured PICA anewysms compared with other ruptured posterior circulation (PC) anewysrns.
Methods This was a retrospective analysis of anonymized data from the Swiss SOS registJ.y (Swiss Study on Anemysmal Subarachnoid Hemonhage; 2009- 2014). Patients with rnptured PC anewysms were subdivided into a PICA and non-PICA group. Clinical, radiologic al, and tJ·.e atment-related variables were identified, and their impact on the neurological outcome was dete1mined in ten11s of rnodified Rankin score at discharge and at 1 year of follow-up for the two groups.
Results Data from 1864 anewysmal subai·achnoid hemorrhage patients were reviewed. There were 264 patients with a ruptured PC anemysm. Seventy-four PICA anemysms represented 28% of the series; clinical and radiological characteristics at admission were comparable between the PICA and non-PICA group. Surgical tJ.·eatJ.nent was accomplished in 28% of patients in the PICA group and in the 4.8% of patients in the non-PICA group. No statistically significant difference was found between the two groups in tem1s of complications after treatment. Hydrocephalus requuing definitive shm1t was needed u12 l .6% of PICA patients
(p = 0.6); cranial nerve deficit was present in average a qua1ter of the patients in both PICA and non-PICA group with no
statistical difference (p = 0.3). A more favorable outcome (66.2%) was reported in the PICA group at discharge (p < 0.05) but this difference faded over time with a sunilar neurological outcome at 1-yeai· follow-up (p = 0 .09) between bath PICA and non PICA group. The Kaplan-Meyer estinrntion showed no significant difference in the mortality rate between bath groups (p = 0.08). Conclusions In the present study, patients with ruptured PICA anemysms had a favorable neurological outcome in more than two
thirds of cases, sunilar to patients with other ruptured PC anemy sms . Surgical tJ.·eatment remains a valid option in a third of cases with ruptured PICA anemysms
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
Anterior Petrosectomy With Intertentorial Approach
Get PDFBackground and objectives: The extradural anterior petrosal approach (EAPA) can present a challenge because it deals with critical structures in a narrow, confined corridor. It is associated with several potential approach-related risks including temporal lobe and venous injuries. Tentorial peeling has the potential to largely eliminate these risks during the approach and may offer more options for tailoring the dural opening to the anatomic region that one wants to expose.
Methods: Anatomic dissections of five adult injected non-formalin-fixed cadaveric heads were performed. Anterior petrosectomy with intertentorial approach (APIA) through a tentorial peeling was completed. Step-by-step documentation of the cadaveric dissections and diagrammatic representations are presented along with an illustrative case.
Results: Tentorial peeling separates the tentorium into a temporal tentorial leaf and posterior fossa tentorial leaf, adding a fourth dural layer to the three classic ones described during a standard EAPA. This opens out the intertentorial space and offers more options for tailoring the dural incisions specific to the pathology being treated. This represents a unique possibility to address brainstem or skull base pathology along the mid- and upper clivus with the ability to keep the entire temporal lobe and basal temporal veins covered by the temporal tentorial leaf. The APIA was successfully used for the resection of a large clival chordoma in the illustrative case.
Conclusion: APIA is an interesting modification to the classic EAPA to reduce the approach-related morbidity. The risk reduction achieved is by eliminating the exposure of the temporal lobe while maintaining the excellent access to the petroclival region. It also provides several options to tailor the durotomies based on the localization of the lesion
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe 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
Disease heterogeneity in IgG4-related hypophysitis: report of two histopathologically proven cases and review of the literature
No full textIgG4-related hypophysitis (IgG4-RH) is a rare disease, which can occur singularly or as manifestation of a systemic IgG4-related disease (IgG4-RD). Less than one hundred cases have been reported in the literature, very few of which were histopathologically documented. We analyzed the clinical, radiological, and histopathological features of two cases of IgG4-RH, the former observed in a 66-year-old man in the context of an IgG4-RD, and the latter affecting a 21-year-old woman, as an isolated lesion. In addition, we performed a comprehensive review of the previously published histopathologically documented cases of IgG4-RH. Pituitary samples from both patients showed dense lymphoplasmacytic infiltration, interstitial and storiform fibrosis, and high numbers of IgG4-positive plasma cells, consistent with IgG4-RH. From the literature review, we retrieved 18 papers reporting a total of 22 cases of histopathologically documented IgG4-RH. The revision of these cases, also including the two reported herein, showed an equal distribution of IgG4-RH in the two sexes, albeit significant clinico-pathological variation was found between cases arisen in female and male patients, respectively. In detail, IgG4-RH females were affected in their second-third decade of life, with a solitary pituitary lesion, low IgG4 serum level, and frequent association with autoimmune disorders. By contrast, IgG4-RH in men was a disease of the elderly, often in the context of a systemic IgG4-RD, with high IgG4 serum levels. Our study shows that IgG4-RH, as currently defined, is a clinically heterogenous disease, with different features in the two sexes. Indeed, cases diagnosed in young women, as our case 2, mostly do not present other evidence of IgG4-RD and might be better classified as lymphocytic hypophysitis with abundant IgG4+ plasma cells. For this reason, the histopathological examination of the pituitary lesion, particularly in female patients, may still be useful for a correct differential diagnosis with other variants of primary hypophysitis
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