1,721,007 research outputs found
Collaborating with Colorectal Surgery to Identify Patients at Risk of Anastomotic Leakage
No full textNot availabl
Maintaining Safe Elective Aneurysm Surgery in the COVID-19 Era
No full textThe respiratory syndrome COVID-19 has had a devastating effect on health, economy, and social life worldwide. The healthcare system of industrialised countries has been at times submerged by the pandemic, leading to some of the most challenging choices in health resource distribution experienced by this generation.
During local COVID-19 prevalence surges, access to operating theatres and intensive care facilities for all but the most urgent surgery has been severely restricted. The workforce and intensive care have been redeployed to deal with the flood of COVID-19 cases. Associated with this limited access to elective theatre, disease specific case prioritisation has been required. Society and healthcare providers tend to be very aware of the need to perform early surgery for cancer diagnoses, and the associated high morbidity and mortality of vascular patients is less well recognised. The high mortality of vascular patients infected with COVID-19 and particularly the risk of pulmonary complications was not widely understood at the start of the pandemic; moreover, there was a high geographical variability in the severity of the COVID-19 distribution, and a standardisation of the hospital strategies was not possible.1, 2, 3,
Endovascular exclusion of abdominal aortic aneurysms and simultaneous resection of colorectal cancer
No full textBackground: No consensus exists on the optimal strategy for treatment of abdominal aortic aneurysm (AAA)associated with colorectal cancer (CRC). The purpose of this study was to evaluate the results of endovascular treatment of AAA with simultaneous resection of CRC. Methods: Twenty-two consecutive patients presenting with AAA associated with a CRC were treated by endovascular AAA exclusion and simultaneous CRC resection. Median diameter of the aneurysm was 6.5 cm (range, 4.8–8 cm). Two patients (9%)had grade I cancer, 5 patients (23%)grade II, 13 patients (59%)grade III, and 2 patients (9%)grade IV. The 2 surgical procedures were performed under the same general anesthesia. Aneurysm exclusion was achieved using an infrarenal aorto-bi-iliac endoprosthesis (13 patients)and using an aorto-bi-iliac endoprosthesis with suprarenal fixation (9 patients), with 1 patient receiving bilateral renal chimney stent implantation. In all cases, vascularization of the hypogastric arteries was preserved. After AAA exclusion, colic resection was carried out by laparotomy with right colectomy (7 patients)and anterior rectocolic resection (15 patients). In all patients, AAA exclusion was controlled by a computed tomographic angioscan (CTA)at 1 month and duplex ultrasound every 6 months, and at some later stage, it was through inclusion of CTA as part of oncology surveillance. The mean duration of follow-up was 42 months (10–120 months). The primary endpoint was composite and regrouped any death occurring during the first 30 days after procedures, any type I endoleak, any aortic reintervention, and any AAA-related mortality. Results: No patient died during the first 30 postoperative days, and no patient was lost to follow-up. No aortic endoprosthesis infection and no type I endoleak were observed. Five endoleaks arising from the lumbar arteries (n = 4)or from the inferior mesenteric artery (n = 1)were identified. As they were not associated with an increase of the AAA diameter >5 mm, they were not treated. 1 colic anastomotic leak and 2 incisional abscesses were successfully cured by local care only. Nine patients (41%)died of cancer evolution during the follow-up period. Conclusions: In this series, treatment of AAA and CRC during the same operative session yields results comparable to those observed when surgery is performed in 2 distinct operative sessions. Synchronous treatment reduced waiting time of colic resection. It may also shorten total hospitalization duration, although this last hypothesis is not supported by comparison with a control group
Finite Element Simulations of the ID Venous System to Treat Venous Compression Disorders: From Model Validation to Realistic Implant Prediction
Full text linkThe ID Venous System is an innovative device proposed by ID NEST MEDICAL to treat venous compression disorders that involve bifurcations, such as the May-Thurner syndrome. The system consists of two components, ID Cav and ID Branch, combined through a specific connection that prevents the migration acting locally on the pathological region, thereby preserving the surrounding healthy tissues. Preliminary trials are required to ensure the safety and efficacy of the device, including numerical simulations. In-silico models are intended to corroborate experimental data, providing additional local information not acquirable by other means. The present work outlines the finite element model implementation and illustrates a sequential validation process, involving seven tests of increasing complexity to assess the impact of each numerical uncertainty separately. Following the standard ASME V&V40, the computational results were compared with experimental data in terms of force-displacement curves and deformed configurations, testing the model reliability for the intended context of use (differences < 10%). The deployment in a realistic geometry confirmed the feasibility of the implant procedure, without risk of rupture or plasticity of the components, highlighting the potential of the present technology
Current status on aortic endografts
No full textEndovascular treatment has become widespread to treat aneurysmal disease, especially located in the aorta. The modern era of abdominal aortic aneurysm repair started between 1986 and 1991, and in the last 30 years, Endovascular Treatment for abdominal aortic aneurysms evolved both due to the development of new materials and devices and the increasing appeal and effectiveness of the endovascular therapy itself. Vascular surgeons are using nowadays different solutions of Endovascular Treatment to treat all the expressions of aortic pathology (aneurysms, dissections and trauma) both in the acute and elective setting. Despite its use in every location of the aorta (the ascending aorta, the aortic arch, the thoracic aorta, thoraco-abdominal aorta, pararenal, iuxtarenal and infrarenal aortic aneurysms and iliac aneurysms), its safety and efficiency, endovascular treatment for aortic aneurysms presents some drawbacks: despite a lower short-term morbi-mortality, reinterventions and long-term patency are higher compared to open repair. In this review, we detail the most used types of endografts according to location, their performances and durability for each device. We conclude by discussing options to overcome ET limitations. Therefore, an obvious question arises: what we need in the future? What can the technological progress gives to physicians to further improve this new way of treating aorta?
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
- …
