1,721,088 research outputs found
Endovascular vs. open treatment of severe aortoiliac occlusive disease – outcomes of a kissing, self-expanding covered stent for reconstruction of the aortic bifurcation
No full text• The kissing stents technique represents the endovascular approach of choice to treat aortoiliac obstructive lesions involving the aortic bifurcation. • Self-expanding covered stents are flexible, conformable and available in long lengths, able to adapt to the often calcific, irregular and long atherosclerotic lesions in this area, and to prevent complications like arterial rupture and distal thromboembolism. • In our experience, the five-year primary patency rate of kissing self-expanding covered stents for the treatment of TASC C-D lesions is 90%, similar to aortobifemoral bypass, although with shorter length of hospitalisation and lower cumulative surgical complication rate. • Clinical presentation, classified as Rutherford category, was the only independent predictor of patency
Standardized approach for four-fenestrated physician-modified endograft to treat complex abdominal aortic aneurysms using Valiant Captivia
No full textWe describe the feasibility and safety of a standardized approach for four-fenestrated physician-modified endograft (PMEG) placement to treat complex abdominal aortic aneurysms using the Valiant Captivia platform (Medtronic). The standardization is based on specific selection criteria for anatomical feasibility, measurement method, and modification technique of a single endograft type. Six cases (two juxtarenal, two pararenal, and two type IV thoracoabdominal aneurysms) were treated, with 24 target vessels incorporated with fenestrations. Four cases were treated in an urgent setting and two were elective. The time modification required was 121 ± 18 minutes. Technical success was 100%, with no mortality or complications at 30 days. Postoperative computed tomography at 3 months demonstrated complete aneurysm exclusion, without a type I or III endoleak, no main graft- or fenestration-related loss of integrity, and no target vessel misalignment or stent fracture. The present standardized approach seems safe and feasible and might represent an initial benchmark for comparison with future studies
Geometrical Analysis and Preliminary Results for the Endovascular Reconstruction of Aortic Bifurcation Using New-Generation Balloon-Expandable Covered Stents in the Kissing Conformation
No full textBackground: The purpose of the study is to perform a postimplantation geometrical analysis and to evaluate early and mid-term outcomes of new-generation balloon-expandable covered stents, used in the kissing conformation to treat obstructive lesions involving the aortic bifurcation. Methods: A single-center retrospective review of all patients who underwent endovascular reconstruction of the aortoiliac bifurcation for obstructive disease, with the use of Viabahn balloon expandable stents (VBX; W. L. Gore & Associates, Flagstaff, AZ) deployed in the kissing conformation, from March 2018 to June 2019 was carried out. Two same-size kissing VBXs were simultaneously deployed from the distal aorta (1.5–2 cm above the aortic bifurcation) to the common iliac arteries; a kissing post-ballooning using compliant balloons was routinely performed to flare the proximal part of the VBX, to adapt to the aortic diameter and morphology. A postoperative computed tomography (CT) angiogram was obtained for all patients for the geometrical assessment. “Precision” of deployment was measured as protrusion mismatch, intended as the longitudinal distance between the stents’ proximal ends. “Conformability” was measured as radial mismatch (area and volume of the “dead space” between the stented lumen and the aortic wall) and D-ratio (ratio of the major and minor axes in the axial view). Symmetry was measured as the ratio between the minor diameter of the 2 kissing stents at the same level. Results: Twenty-eight patients (56 limbs) underwent endovascular treatment with kissing VBXs for Trans-Atlantic Inter-Society Consensus II C (n = 10, 36%) or D (n = 18, 64%) lesions involving the aortic bifurcation. Two 8-mm diameter (“8L”) VBX stents were used in most cases (n = 32, 57%). At the postoperative CT, the mean protrusion mismatch was 0.8 ± 1.7 mm and was <5 mm in all cases. The mean radial mismatch area was 20.4 ± 10.6 mm2, and the mean radial mismatch volume was 2442 ± 182 mm3. The mean D-ratio was 1.4 ± 0.2. Early procedural and postprocedural complication rates were 4% and 0%, respectively. After 9.7 ± 4.2 months of follow-up, no cases of limb occlusion or restenosis occurred. Conclusions: The use of kissing VBX stents may represent a valid option for the treatment of obstructive lesions involving the aortic bifurcation, with excellent early and mid-term outcomes and achievement of optimal stents geometry
Changes of xylem sap ionic content and stem hydraulics in response to irradiance in Laurus nobilis L.
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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
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