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Translational surgical research on patients with chylous ascites: effectiveness of the application of a peritoneo-venous shunt
No full textIntroduction. Chylous reflux is mainly related to lymphatic valvular insufficiency due to chyle-lymphangectasia and dysplasia. The etiology of chylous ascites (also called chyloperitoneum) includes primary abnormalities of lymphatic or chyliferous vessels development or secondary causes, such as trauma, surgery or tumors. Conservative approach is the main treatment and it includes medical and nutritional therapy. In the event of failure of conservative therapy, endovascular procedures and surgical therapy can be used. However, there are cases, especially due to primary dysplastic nature, that do not respond to the combined treatment reported above and require the implantation of a peritoneum-venous shunt (PVS) (such as Denver® Shunts, traditionally used in the eighties for palliation of refractory malignant ascites) or other drainage devices.
Objective. The aim of this study is to evaluate the effectiveness in chylous ascites of the application of a device for the peritoneum-venous shunt, in order to achieve the drainage of chylous ascites in a central vein, for the recovery of immunological and nutritional components (such as proteins, albumin, lymphocytes) into the blood circulation. Where peritoneum-venous shunts were not successful, also other drainage devices were evaluated, to temporarily drain the fluids from the abdomen.
Materials and methods. The research focused on 3 patients (17- and 47-years old female and 57 years old male) with recurrent spontaneous chyloperitoneum that were studied and treated under local anesthesia with the insertion of a Denver-type peritoneum-jugular shunt. The venous end was inserted into a jugular vein via a subcutaneous tunnel that was created and the peritoneal end of the shunt was placed at the most caudal part of the pelvis. The Denver shunt has a unidirectional pump that was placed in a subcutaneous pocket over the lower ribs and allowed daily manual compressions and movement of fluid. Complications related to the implant of the valve led us to replace it with an external percutaneous drainage device (Relief® system).
Results and conclusions. All PVS implants were successfully performed. Follow-up period was 27-32 months (clinical, laboratory and echo-graphic assessment). Significant symptomatic relief was obtained in all patients. All patients initially showed a reduction in abdominal circumferences and body weight. Serum albumin, lymphocytes and immunoglobulins levels increased significantly following PVS placement. Postoperative complications included thrombosis of the jugular vein, treated with low weight heparin subcutaneously. In one patient there was a temporary recurrence of the ascites, spontaneously solved, following a proper low-fat diet. In the first period, all the patients had a significant improvement of the clinical conditions with an acceptable control of chylous ascites and with an improvement of quality of life for more than one year. Then, permanent and unsolvable occlusion of the PVS and venous thrombosis occurred so all PVS were removed and in 2 patients a Relief ®system was implanted to drain the remaining ascites.
The idea of deriving ascites in a jugular vein did not lead to satisfactory long-term results in patients with chylous ascites, so it was necessary to switch to the use of other devices. The main problem is the density of the chylous fluid and the presence of coagulation factors that promote thrombosis. In the future it will be necessary to evaluate other technical solutions and special materials that can allow us to overcome the limits of the proposed method
Long‐term patency of multiple lymphatic‐venous anastomoses in cancer‐related lymphedema: A single center observational study
No full textObjectives: Lymphedema is always initially treated by combined decongestive physiotherapy (CDP). Those cases, refractory to CDP, may be managed by surgical therapy. One of the most used microsurgical procedures is represented by the technique of lymphatic-venous anastomosis (LVA). But very few papers report long term results of LVA. The aim of this study is to assess the long-term patency of multiple lymphatic-venous anastomosis (MLVA) for the treatment of secondary lymphedemas.
Methods: From January 2014 to December 2014, 101 patients (mean age: 56.94 +/- 8.98 years; female/male: 86/15) affected by secondary cancer-related lymphedema (38 lower and 63 upper limbs) were treated by MLVA. All lymphedemas had previously been treated by conservative therapy without sustained results. Many patients (78%) had 1-3 episodes of acute lymphangitis/year. Lymphoscintigraphy, venous duplex-ultrasonography, and abdominal or axillary ultrasound investigation were performed preoperatively. MLVA patency was assessed by the lymphatic transport index (LyTI) and lymphoscintigraphic pattern.
Results: At 1 year after surgery, excess volume reduction was 75%-90% in the early stage II secondary lymphedemas, and 60%-75% in the late stage II. The decrease in volume maintained stability in the 5-years follow-up period. Two more advanced lower and one upper limb lymphedemas had 45%-60% reduction. LyTI showed a significant decrease between the preoperative mean value (31.7 +/- 9.43) and after 18 months from surgery (11.2 +/- 1.91) (p < .001). MLVA patency was shown in 98 (97%) patients. No patients had evidence of postoperative lymphangitis.
Conclusions: This study demonstrated the long-term patency of MLVA in the treatment of cancer-related lymphedemas
Microsurgery for groin lymphocele and lymphedema after oncologic surgery
No full textGroin lymphocele (GL) is a frequent complication of inguinal lymph node dissection, and conservative treatment is not always successful. Different surgical methods have been used to treat lymphoceles arising from lymphatics injured during groin surgery. However, they all involve the closure of lymphatics merging at the lymphocele, increasing the risk of postoperative lower limb lymphedema or of worsening lymphedema if already clinically evident. We assessed the efficacy of a diagnostic and therapeutic protocol to manage inguinal lymphoceles using lymphoscintigraphy (LS) and microsurgical procedures. Sixteen GL [seven associated with leg lymphedema (LL)] were studied by LS preoperatively and treated by complete excision of lymphocele and microsurgical lymphatic-venous anastomoses between afferent lymphatics and a collateral branch of great saphenous vein. Lower limb lymphatics were identified intraoperatively using Patent Blue dye injection. Nine patients without lymphedema had complete healing of lymphocele and no appearance of lower limb postoperative lymphedema. The other seven patients with associated secondary lymphedema had complete disappearance of lymphocele and a remarkable reduction of leg volume. Four of them completely recovered without the need of any compression garment, after the first year postoperative. Inguinal lymphocele nonresponsive to conservative treatment can be advantageously studied by LS and successfully treated by microsurgical reconstructive procedures, above all if associated to LL
Diagnosis and treatment of chylous disorders
No full textAuthors report their clinical experience in the treatment of chylous disorders due to congenital dysplastic malformation or secondary to oncological operations with nodal dissection. They report proper diagnostic investigations including above all traditional oil contrast lymphangiography associated with CT scan. A sequential therapeutical sequence is finally described including conservative procedures, laparoscopic approach and microsurgical methods
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
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