1,720,998 research outputs found
Endurant stent-graft: A 2-year, single-center experience with a new commercially available device for the treatment of abdominal aortic aneurysms
No full textPurpose: To evaluate early and midterm results of the Endurant stent-graft in the treatment of abdominal aortic aneurysms (AAAs). Methods: From November 2007 to December 2009, 156 patients (142 men; mean age 73.6 years, range 51-90) were treated with the Endurant stent-graft at our center. More than half (106, 67.9%) had hostile proximal neck anatomy. Early (30-day) technical success, clinical success, major morbidity, and mortality rates were analyzed, as well as estimated 2-year survival, freedom from types I/III endoleak, freedom from graft thrombosis, freedom from any device-related reinterventions, and factors affecting 2-year freedom from types I/ III endoleak. Results: Immediate intraoperative technical and clinical success was achieved in all cases. In 14 (9%) cases with a proximal neck <5 mm long, a "chimney" technique was used. At discharge, computed tomography demonstrated 2 (1.3%) type I endoleaks. At 30 days, 4 (2.6%) patients had died (2 were urgent cases); the 30-day major morbidity was 7.7%. The overall 30-day technical success and clinical success rates were 98.7% and 95.5%, respectively. During a mean 9-month follow-up (range 1-24), 3 patients died (one of them from AAA rupture). Estimated survival, freedom from types I/III endoleak, freedom from graft thrombosis, and freedom from any device-related reinterventions at 2 years were 94.7%, 96.9%, 97.8%, and 92.6%, respectively. Conclusion: The Endurant stent-graft seems to be safe and effective in endovascular aneurysm repair (EVAR), even in patients with hostile aortoiliac anatomy. However, perioperative and midterm complications occur, which could be explained by the expansion of indications for EVAR. Further studies are needed to evaluate the long-term results. © 2010 by the International Society of Endovascular Specialists
Evaluation of the Endurant stent graft under instructions for use vs off-label conditions for endovascular aortic aneurysm repair
No full textBackground: This study evaluated the early and intermediate results of endovascular aortic aneurysm repair (EVAR) using the Endurant stent graft (Medtronic Cardiovascular, Santa Rosa, Calif) in patients treated according to device-specific instructions for use (IFU) for the proximal aortic neck compared with those obtained in patients treated in an off-label (OL) situation. Methods: Between November 2007 and March 2010, 177 consecutive patients with abdominal aortic aneurysms (AAAs) were treated with the Endurant stent graft at our centers. The IFU for the Endurant stent graft included a proximal neck of 15 mm in length and <75° of angulation or 10 mm of neck length and <60° of angulation. The 121 patients (68.4%) operated on according to IFU were compared with 56 (31.6%) who underwent EVAR in OL circumstances to evaluate significant differences in demographics, intraoperative technical factors, and early (30 days) and intermediate outcomes (1 year). Results: Significantly more patients were aged >80 years in the OL group (37.5% vs 19%, P =.008), and they also had larger aneurysms (59 ± 10.6 vs 55.9 ± 10.8 mm, P =.05) and required a longer procedure time (69.3 ± 27.2 vs 60.8 ± 20.4 minutes, P =.02). At 30 days, the risk of type I endoleak was higher in the OL group (2 patients, 3.6% vs 0 in IFU), but this did not reach statistical significance (P =.09). The two groups were similar in rates of perioperative mortality, major morbidity, technical success, clinical success, complications, and reinterventions. At 1 year, there were no differences between the two groups in survival, freedom from any device-related reinterventions, and freedom from graft thrombosis. Estimated 1-year freedom from type I endoleak was 100% in the IFU group vs 93.3% in the OL group (P =.01). Conclusions: In patients with both normal and complex anatomy of the proximal aortic neck, the Endurant stent graft obtained acceptable results, with no difference in survival, morbidity, or reinterventions. However, there was a greater risk of type I endoleak when OL indications were applied. Longer term follow-up is required to evaluate the effectiveness of this endograft in preventing late aneurysm-related complications. © 2011 Society for Vascular Surgery
The impact of aortic remodeling on the performance of bridging stents after branched endovascular aortic repair
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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
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