Introdução: A termoablação vem substituindo a cirurgia convencional no tratamento cirúrgico do refluxo da veia safena magna em pacientes portadores de varizes dos membros inferiores. Contudo, a termoablação apresenta elevados custos. A Eletrocoagulação endovenosa pode, seletivamente e de forma segura, causar necrose da parede da veia safena magna, mas seus resultados clínicos nunca foram estudados previamente. O objetivo deste estudo é comparar a Eletrocoagulação e a Radiofrequência no tratamento da insuficiência da veia safena magna, considerando eficácia, complicações e impacto na qualidade de vida. Métodos: Trata-se de um ensaio clinico prospectivo, randomizado e duplo-cego. Os pacientes portadores de varizes de membros inferiores e refluxo de veia safena magna ao Eco Doppler colorido foram randomizados em dois grupos de tratamento: Eletrocoagulação ou Radiofrequência. O seguimento dos pacientes ocorreu após uma semana, três meses e seis meses do procedimento. O desfecho primário foi considerado como oclusão da veia safena magna ao Eco Doppler colorido e o desfecho secundário, como a taxa de complicações e a melhora na qualidade de vida, mediante pontuação do Escore de Gravidade Clínica Venosa e Questionário Aberdeen para Veias Varicosas. Resultados: Foram incluídos no estudo 57 pacientes, totalizando 85 veias safenas magnas tratadas, sendo que 43 foram submetidas à Radiofrequência e 42, à Eletrocoagulação. Não houve diferença estatisticamente significante entre os grupos, no pré-operatório, em relação à idade (P = 0,264), gênero (P = 0,612), Escore de Gravidade Clínica Venosa (P = 0,125), Questionário Aberdeen para Veias Varicosas (P = 0,054), diâmetro (P = 0,880) e profundidade (P = 0,763) da veia safena magna tratada. No intraoperatório, imediatamente após a realização da termoablação, todas as veias safenas magnas submetidas à eletrocoagulação apresentaram ausência de fluxo no segmento tratado e incompressibilidade, enquanto 12 membros ainda exibiam fluxo em sua veia safena magna tratada (P < 0,001) e 9 veias apresentavam-se compressíveis (P < 0,001), quando submetidas à Radiofrequência. A principal complicação pós-operatória encontrada foi a parestesia, não havendo significância estatística quanto à sua presença entre os grupos (P = 0,320). O tempo de retorno às atividades rotineiras foi menor no grupo da Eletrocoagulação em relação ao grupo da Radiofrequência (P = 0,026). Não houve diferença entre os grupos em relação à taxa de oclusão da veia safena magna no seguimento de 3 meses (P = 0,157) e 6 meses (P = 0,157), bem como na melhora da pontuação do Questionário Aberdeen para veias varicosas após 3 meses (P = 0,786) e 6 meses (P = 0,401) e na melhora da pontuação do Escore de Gravidade Clínica Venosa após 3 meses (P = 0,324) e 6 meses (P = 0,367). Conclusões: A Eletrocoagulação revelou-se um método eficaz para ablação da veia safena magna, com taxa de oclusão venosa, ocorrência de complicações e impacto na qualidade de vida semelhantes àqueles encontrados na Radiofrequência. / Background: Thermoablation has been replacing conventional surgery in the surgical treatment of great saphenous vein reflux in patients with lower limb varicose veins; however, thermoablation is expensive. Intravenous Electrocoagulation may, selectively and safely, cause necrosis of the great saphenous vein wall, but the clinical results have never been studied. The objective of this study was to compare Electrocoagulation and Radiofrequency in the treatment of great saphenous vein insufficiency, considering efficacy, complications and effect on quality of life. Methods: This is a prospective, double-blind, randomized clinical trial. Patients with lower limb varicose veins and great saphenous vein reflux confirmed by duplex ultrasonography were randomized into two treatment groups: Electrocoagulation or Radiofrequency. Patients were followed-up 1 week, 3 months and 6 months after the procedure. Occlusion of the great saphenous vein confirmed by duplex ultrasonography was considered the primary outcome and the rate of complications and improvement in quality of life, using the Aberdeen Varicose Veins Questionnaire and Venous Clinical Severity Score, were the secondary outcome. Results: Fifty-seven patients were included, with a total of 85 treated great saphenous veins; 43 were treated with Radiofrequency and 42 with Electrocoagulation. There was no statistically significant difference between the groups regarding age (P = 0,264), sex (P = 0,612), Venous Clinical Severity Score (P = 0,125), Aberdeen Varicose Veins Questionnaire score (P = 0,054), diameter (P = 0,880) and depth (P = 0,763) of the treated great saphenous vein. In the intraoperative period, immediately after thermoablation, all great saphenous veins treated with Electrocoagulation presented no flow in the treated segment and incompressibility, while 12 limbs still had flow in treated great saphenous vein (P < 0,001), and 9 veins showed compressibility (P < 0,001) when treated with Radiofrequency. The main postoperative complication was paresthesia; however there was no statistical significance between the groups (P = 0,320) regarding its presence. Time to return to routine activities was lower in the Electrocoagulation group than in the Radiofrequency group (P = 0,026). There was no difference between the groups at the 3-month (P = 0,157) and 6-month (P = 0,157) follow-ups regarding occlusion of the great saphenous vein and in improvement of Aberdeen Varicose Veins Questionnaire score after 3 months (P = 0,786) and 6 months (P = 0,401) and Venous Clinical Severity Score after 3 months (P = 0,324) and 6 months (P = 0,367). Conclusions: Electrocoagulation has been shown to be an effective method for ablation of the great saphenous vein, with venous occlusion rate, occurrence of complications, and effect on the quality of life similar to that with Radiofrequency.

Several mechanisms have been proposed to explain the process of vein pattern formation in plant tissues. The most widely accepted amongst biologists is the canalization hypothesis, derived from pea root and stem experiments. According to this hypothesis, a signal, thought to be the phytohormone auxin, is transported polarly from cell to cell from the shoot to the root and is canalized progressively into narrow channels of high auxin fluxes that later differentiate to become vascular tissue. In this project, we set out to test whether auxin canalization drives vein pattern formation, using Arabidopsis thaliana mutants with increased auxin transport (max4-1, max3-9, max2-1 and max1-1). We predicted that the mutants would have distinct vein patterns and especially different angles between the primary and secondary veins, compared to the wild type. First rosette leaves of 15 plants per genotype were harvested for analysis each day from 7 to 17 days after sowing, giving a total of eight hundred twenty-five leaf samples to analyze. Venation patterns were extracted and analyzed using custom-made software written with Matlab. Overall, compared with the wild type, mutants with the highest auxin transport (max4-1 and max3-9) had different vein patterns at early developmental stages, confirming a role for auxin transport in vein patterning. However, veins of mutants and wild type connected at similar angles, which is not consistent with the auxin canalization hypothesis, as originally formulated.

O objetivo deste estudo foi avaliar retrospectivamente, em longo-prazo, os preditores de recorrência de fibrilação atrial paroxística (FA) em 139 pacientes submetidos à ablação por radiofreqüência, através das técnicas ostial ou extraostial de abordagem do átrio esquerdo, associadas ou não à ablação do istmo cavo-tricuspídeo (ICT). Variáveis pré, intra e pós-ablação foram avaliadas por análise uni e multivariada, para determinar os preditores de recorrência da FA após um procedimento. Observou-se que maior tempo de história de FA, uso de mais antiarrítmicos e recorrência de FA dentro de 60 dias pós-procedimento, aumentaram o risco de recorrência de FA a longo-prazo. Por outro lado, a associação de flutter atrial e a ablação concomitante do ICT, reduziram o risco de recorrência ao final de 33 ±12 meses. / The objective of this study was to evaluate in retrospect, in long-term, the predictors of late recurrence of atrial fibrillation (AF) in 139 patients submitted to the ablation by radiofrequency, through the techniques ostial or extra-ostial of approach of the atrium left, associated or not to the ablation of the cavotricuspid isthmus(ICT). Variables pre, intra and post-ablation were appraised for analysis uni and multivariated, to determine the predictors of recurrence of AF after one procedure. It was observed that larger time of history of AF, use of more drugs and recurrence of AF within 60 days after procedure; they increased the risk of recurrence of AF in long-term. On the other hand, the association of atrial flutter and the concomitant ablation of ICT, they reduced the recurrence risk at the end of 33 ±12 months.

This diploma thesis deals with different ways of grayscale image processing of veins in a finger of human hand. The process consists of vein structure extraction, and then this structure is compared with collection of provided snapshots. First of all we introduced problem of biometric systems and image processing. There are presented also some commercial solutions from the same field. Within the detailed description of image processing we suggested different modifications in adaptive thresholding algorithm, feature extraction, which continues into comparison of vein structures. Thesis is closed by testing and final review.

Indiana University-Purdue University Indianapolis (IUPUI) / The passive properties of the venous wall are important in the development of venous pathology. Increase in venous pressure due to retrograde flow (reflux) and obstruction of venous flow by intrinsic and extrinsic means are the two possible mechanisms for venous hypertension. Reflux is the prevailing theory in the etiology of venous insufficiency. The objective of this thesis is to quantify the passive biomechanical response and structural remodeling of veins subjected to chronic venous reflux and hypertension. To investigate the effects of venous reflux on venous mechanics, the tricuspid valve was injured chronically in canines by disrupting the chordae tendineae. The conventional inflation-extension protocol in conjunction with intravascular ultrasound (IVUS) was utilized to investigate the passive biomechanical response of both control common iliac veins (from 9 dogs) and common iliac veins subjected to chronic venous reflux and hypertension (from 9 dogs). The change in thickness and constituent composition as a result of chronic venous reflux and hypertension was quantified using multiphoton microscopy (MPM) and histological evaluation. Biomechanical results indicate that the veins stiffened and became less compliant when exposed to eight weeks of chronic venous reflux and hypertension. The mechanical stiffening was found to be a result of a significant increase in wall thickness (p < 0.05) and a significant increase in the collagen to elastin ratio (p < 0.05). After eight weeks of chronic reflux, the circumferential Cauchy stress significantly reduced (p < 0.05) due to wall thickening, but was not restored to control levels. This provided a useful model for development and further analysis of chronic venous insufficiency and assessment of possible intervention strategies.

Introduction: Cyanoacrylate gluing technique is the least strenuous treatment of varicose trunks which does not necessitate tumescent anaesthesia and post procedural stocking compression. In response to the long-term unavailability of commercial kits with N-butyl-2-cyanoacrylate (Histoacryl) in the Czech Republic, we used a modified technique, which is based on the technique of endovascular treatment of AV malformations in the brain and uses a mixture of cyanoacrylate and Lipiodol to clog. We evaluated the success of the method, complications and clinical improvement of chronic venous insufficiency. Parts of the work are histological findings of collected samples of veins at various time intervals. In an in vitro experiment, we compared the bond strength of a bonded shear to a tear device. The adhesive mix values used were compared with those of commercially available adhesives for this purpose. Patients and methods: Fifty-six limbs in 49 patients suffering from great saphenous vein or small saphenous vein insufficiency in combination with symptomatic chronic venous insufficiency and complicating comorbidities were treated with a modified endovascular cyanoacrylate glue application technique. A histopathological examination was conducted on vein samples from six. In each patient a sample of the...

Yes / To determine whether or not jugular venous reflux (JVR) is associated with structural brain parenchyma changes in individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD). 16 AD patients (mean (SD): 81.9 (5.8) years), 33 MCI patients (mean (SD): 81.4 (6.1) years) and 18 healthy elderly controls (mean (SD): 81.5 (3.4) years) underwent duplex ultrasonography and magnetic resonance imaging scans to quantify structural brain parenchyma changes. Normalized whole brain (WB), gray matter (GM) and white matter (WM) volumes were collected, together with CSF volume. JVR was strongly associated with increased normalized WB (p = 0.014) and GM (p = 0.002) volumes across all three subject groups. There was a trend towards increased WB and GM volumes, which was accompanied by decreased CSF volume, in the JVR-positive subjects in both the MCI and AD groups. When the MCI and AD subjects were aggregated together significant increases were observed in both normalized WB (p = 0.009) and GM (p = 0.003) volumes for the JVR-positive group. No corresponding increases were observed for the JVR-positive subjects in the control group. Through receiver operating characteristic analysis of the brain volumetric data it was possible to discriminate between the JVR-positive and negative AD subjects with reasonable accuracy (sensitivity = 71.4%; specificity = 88.9%; p = 0.007). JVR is associated with intracranial structural changes in MCI and AD patients, which result in increased WB and GM volumes. The neuropathology of this unexpected and counterintuitive finding requires further investigation, but may suggest that JVR retrogradely transmits venous hypertension into the brain and leads to brain tissues swelling due to vasogenic edema.

This critical synopsis of prior work by Clive Beggs is submitted in support of a PhD by published work. The work focuses on venous and cerebrospinal fluid (CSF) anomalies associated with multiple sclerosis (MS) and other neurological diseases. MS is characterized by focal inflammatory lesions, which are often venocentric. Recently a vascular syndrome, chronic cerebrospinal venous insufficiency (CCSVI) has been linked with MS. This syndrome, which is characterized by constricted cerebral venous outflow, has become mired in controversy, with various studies producing conflicting findings, with the result that the science associated with CCSVI has become obscured. Clive Beggs work seeks to bring clarity to the debate surrounding CCSVI by characterizing physiological changes associated with constricted cerebral venous outflow. The work submitted here involves collaborative studies with Robert Zivadinov (University of Buffalo), Paolo Zamboni (University of Ferrara), and Chih- Ping Chung (National Yang Ming University of Medicine). The key findings of these studies are: (i) MS patients, diagnosed with CCSVI, exhibit greatly increased hydraulic resistance of the cerebral venous drainage system; (ii) MS patients experience loss of the small cerebral veins; (iii) MS patients exhibit reduced CSF bulk flow, consistent with mild venous hypertension; (iv) MS patients exhibit increased CSF pulsatility in the Aqueduct of Sylvius, which appears to be linked with mild venous hypertension associated with CCSVI; and (v) jugular venous reflux is associated with white matter and parenchymal volumetric changes in Alzheimer’s patients. Collectively, these findings suggest that extracranial venous anomalies are associated with changes in the intracranial physiology.

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