1,720,961 research outputs found
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
Results of resection of carotid body tumors with and without lymphnodes’ dissection
No full textBackground: Carotid body tumor (CBT) is a slow-growing tumor arising from the carotid body, a chemoceptor organ lying behind the carotid artery bifurcation. Although rarely, metastases can occur distally through the hematogenous route and through the lymphatic route.to the cervical lymphnodes. The purpose of this study was to assess whether lymphnodes’ resection should systematically be associated with the primary resection of a CBT. Methods: A retrospective analysis of 82 patients, 52 women of a mean age of 42 years undergoing resection of 88 CBT from 1994 to 2019. CBT were divided into 2 groups. Tumors in group A (n = 23, 26%) were treated by resection of the mass followed by a selective latero-cervical lymphadenectomy; tumors in group B (n = 65, 74%) underwent isolated resection of the mass. The study's primary endpoints were postoperative stroke/mortality rate, disease-specific survival and rate of local and distant recurrence of the disease. Results: Postoperative stroke-mortality rate was nil. One patient in group A (4.3%) presented a minor weakness of the contralateral arm, completely regressive within 12 h. One patient in group B (1.5%) died of liver and lung metastases 51 months after operation, no patient died of recurrent disease in group A (p =.62). No nodal recurrence was observed in group A, whereas one patient in group B (1.5%) presented nodal recurrence 39 months after primary tumor resection (p =.58) Conclusion: Selective lymphadenectomy associated with CBT resection does not increase the overall long-term survival and cannot be considered mandatory. It may help to better define the stage of the disease and to plan eventual adjuvant treatments
Long-term results of polytetrafluoroethylene versus saphenous vein repair of degenerative carotid artery aneurysm
No full textObjective: To compare the results of polytetrafluoroethylene (PTFE) and great saphenous vein (GSV) bypass after resection of a degenerative aneurysm of the carotid artery. Methods: From January 1994 to November 2017, 37 patients (27 men) with a mean age of 58 years (range, 39-82 years) with a degenerative aneurysm of the carotid artery (median diameter, 28 mm; range, 19-42 mm), underwent resection of the aneurysm followed by a bypass with either a GSV (n = 10) or a PTFE prosthesis (n = 27). Although 31 patients were asymptomatic, 6 patients were symptomatic: transient ischemic attack (n = 4), minor stroke (n = 1), and compression of the hypoglossal nerve (n = 1). The preoperative workup included duplex ultrasound examination of the arteries to the head, and angiography or computed tomography angiography. All patients were operated under general anesthesia and six were intubated through the nose. Sixteen patients were monitored through transcutaneous oximetry. No shunt was used in this series. In 10 patients receiving a PTFE graft, the external carotid artery was implanted in the prosthesis. Mean follow-up was 16.9 ± 2 years (95% confidence interval, 14.5-19.3 years). Primary end points were the 30-day combined stroke/death rate, graft infection, late graft patency, and late stroke-free survival. Secondary end points were cranial nerve injury and length of postoperative hospital stay. Results: Postoperative mortality was nil in both groups. One postoperative stroke was observed in the PTFE group, whereas none occurred in the GSV group (P =.84). No graft infection was observed in either group. At 10 years, survival in the GSV group was 80 ± 12%, and survival in the PTFE group was 76 ± 8% (log-rank [Mantel-Cox], P =.85). In the GSV group, graft patency at 7 and 10 years was 85 ± 13%. In the PTFE group B, graft patency was 100% (log-rank [Mantel-Cox], P =.12). No late stroke was observed. Two transient cranial nerve injuries were observed in the GSV group (20%) and two in the PTFE group (8%) (P =.97). Length of hospital stay was comparable in both groups (GSV group, 6 days; PTFE group, 5 days; P =.12). Conclusions: This study suggests that, after resection of a degenerative aneurysm of the carotid artery, bypass with a PTFE prosthesis gives comparable results to those obtained with the GSV. We recommend sparing the GSV and instead using a PTFE prosthesis in patients with a degenerative aneurysm of the carotid artery
Intravascular ultrasound-assisted endovascular exclusion of penetrating aortic ulcers
No full textBackground: Penetrating aortic ulcer (PAU) is an atherosclerotic lesion penetrating the elastic lamina and extending into the media of the aorta. It may evolve into intramural hematoma, focal dissection, pseudoaneurysm, and eventually rupture. The purpose of this study was to evaluate the effectiveness of a totally intravascular ultrasound (IVUS)-assisted endovascular exclusion of PAU. Methods: Thirteen consecutive patients (median age 66 years) underwent IVUS-assisted endovascular exclusion of PAU. The primary end points were fluoroscopy time, radiation dose, and occurrence of type I primary endoleak. Secondary end points were postoperative mortality and morbidity, arterial access complications, postoperative length of stay in the hospital, and occurrence of type II endoleaks. Results: The median fluoroscopy time was 4 min (4–5). The median radiation dose was 4.2 mGy (3.9–4.5). A proximal and distal landing zone of at least 2 cm could be obtained in all the patients. No patient presented a type I endoleak. No postoperative mortality, no morbidity, or arterial access complication was observed. The median length of postoperative stay in the hospital was 2 days (2–3). The median length of follow-up was 25 months (9.2–38.7). One late type II endoleak was observed (7.7%), because of reflux from the intercostal arteries, without the need for additional treatment. Conclusions: IVUS-assisted endovascular treatment of PAU allows durable exclusion of PAU with a short fluoroscopy time and no need for injection of contrast media. Further series are needed to confirm the results of this preliminary study
Results of axillofemoral bypass for aorto-iliac occlusive disease.
No full textThe purpose of this study was to review our results with axillofemoral by-passes performed for aortoiliac occlusive disease. Fifty patients receiving 51 axillofemoral by-passes from January 1989 to December 1994 were retrospectively reviewed. The 30-day post-operative mortality was 4%. Seven patients (14% presented graft-related local complications and all but one required reoperation. Five patients were lost to follow-up, the mean length of which was 36 months (16-74 months). Forty-nine per cent of the patients died during the follow-up period. At 36 months, the primary patency rate was 51%, the secondary patency rate was 69%, and limb valvage rate was 57%. A statistical difference was seen in the secondary patency rate between axillobifemoral by-pass (87%) and axillo-unifemoral by-pass (56%) at 36 months (P < 0.01), but no difference was seen in the limb salvage rate at 36 months between the two configurations of the by-pass (94% vs 81%) (P=NS). Twenty patients (40%) operated upon for acute ischemia had a significantly higher post-operative mortality rate (10% vs 0), a significantly higher amputation rate (20% vs 6.6%) and a significantly lower patency rate of by-pass (26% vs 63%) (P < 0.01), than the 30 patients (60%) operated on for claudication, rest pain or trophic ulcers. Our findings indicate that the results of axillofemoral by-pass are significantly influenced by the selection of patients for operation, namely the clinical status of ischaemic symptoms, and that since the overall results of axillofemoral by-pass are inferior to those of aortofemoral by-pass, this treatment should be restricted to patients at high risk of aortic clamping
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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