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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Vascular wall responses to bypass grafting : studies in mice /

Österberg, Klas, January 2008 (has links)
Diss. (sammanfattning) Göteborg : Univ., 2008. / Härtill 4 uppsatser.
72

Enhanced adrenergic sensitivity of mesenteric veins comparied to arteries and its relation to calcium utilization and handling

Hiavacova, Alexandra. January 2008 (has links)
Thesis (Ph.D.)--Michigan State University. Dept. of Pharmacology and Toxicology, 2008. / Title from PDF t.p. (viewed on July 10, 2009) Includes bibliographical references (p. 226-256). Also issued in print.
73

Lesão letal transfixante de veia cava-justa-hepática e tratamento com endoprótese revestida: um novo modelo experimental / Transfixing lethal injury of the juxtahepatic vena cava and treatment with a stent graft: a new experimental model

Rina Maria Pereira Porta 06 July 2004 (has links)
As lesões das veias justa-hepáticas apresentam mortalidade elevada apesar das diferentes técnicas cirúrgicas de tratamento. Os objetivos desse estudo são: a) construir um modelo experimental de lesão letal transfixante de veia cava inferior (VCI) justa-hepática por técnica endovascular, e avaliar as alterações hemodinâmicas decorrentes dessa lesão. b) tratar a lesão por meio de reposição volêmica inicial e controle do sangramento com a colocação de endoprótese revestida (ER), c) acompanhar clinicamente o pós-operatório com ultra-som Doppler (USD) e cavografia. d) avaliar as alterações anatomopatológicas da VCI com a ER. Vinte cães anestesiados e monitorados [freqüência cardíaca (FC), pressão arterial média (PAM), pressão na VCI, pressão vesical, pressão peritoneal] foram submetidos a lesão transfixante da VCI justa-hepática, por técnica endovascular. Após a reposição volêmica inicial foram divididos em dois grupos: controle (GI)) e experimento (GII). O GI ficou em observação e quando a PAM atingiu níveis entre 40 e 30 mm Hg foi submetido a laparotomia para avaliação do sangramento e da lesão. O GII foi tratado com ER e acompanhado clinicamente com USD e cavografia após 4 (GIIA) e 8 semanas (GIIB) quando foram sacrificados e a VCI com ER foi analisada. O GI apresentou aumento significativo das pressões peritoneal, vesical e da VCI, hipotensão arterial, bradicardia e óbito após 80 minutos. No GII a sobrevida foi de 100%, sem repercussões clínicas. O USD e a cavografia mostraram que todas as ERs encontravam-se pérvias. O Doppler revelou padrão de fluxo monofásico pulsátil nos segmentos estudados. Ao US, as medidas dos diâmetros da ER nas 2ª (7,89 ± 1,20 mm), 4ª (7,24 ± 1,72 mm) e 8ª (8,04 ±1,15 mm) semanas, não mostraram diferenças estatísticas significantes. Na cavografia as medidas dos diâmetros da VCI antes da colocação da ER, logo após a sua colocação e após 4 e 8 semanas, não mostraram diferenças estatisticamente significantes entre os GIIA e GIIB. Esses dados analisados para o GII como um todo, mostram diferenças estatisticamente significantes; VCI (11,74 ± 0,86 mm) T=1,00 p= 0,007, após a colocação da ER (12,86 ± 0,41 mm) T= 0,00 p= 0,008 e no período tardio (8,44 ± 2,00 mm) T= 0,00 p= 0,005. A média da taxa de redução do diâmetro da luz da ER foi de 27,43 ± 20,00%. As medidas, em cm de H2O, da pressão na VCI, cranial (0,55 ± 0,50), caudal (1,15 ± 1,76) e no interior da ER (0,75 ± 0,63), não mostraram diferenças estatisticamente significantes. No estudo da VCI com ER, observamos a formação de neoíntima mais espessa do que às camadas média e íntima. Na área da lesão, a camada média estava seccionada e cicatrizada por tecido fibroconjuntivo. Concluindo, a) criamos um modelo experimental de lesão letal transfixante de VCI justa-hepática por técnica endovascular com mortalidade de 100% dos casos após 80 minutos da lesão, provocando hemoperitônio volumoso com aumento significante da pressão peritoneal, b) tratamos essa lesão com ER com sobrevida de 100%, c) verificamos através do USD e cavografia a perviedade da ER após 2, 4 e 8 semanas do tratamento, d) observamos espessamento significante da neoíntima com redução de 27% do diâmetro da luz, sem repercussão clínica ou aumento de gradiente pressórico / Juxtahepatic vein injuries present a high mortality rate despite the different surgical techniques for their treatment. The objectives of this study are: a) to develop an experimental model of transfixing lethal injury of the juxtahepatic inferior vena cava (IVC) through endovascular technique and to evaluate the hemodynamic alterations caused by this injury, b) to treat the lesion with initial volume replacement and hemorrhage control with the insertion of a stent graft (SG), c) to clinically follow the posttreatment period with Doppler ultrasound (DUS) and cavography, d) to evaluate the anatomopathological alterations of the IVC with the SG. Twenty anesthetized and monitored dogs [heart rate (HR), mean arterial pressure (MAP), vesical and, peritoneal pressure] were submitted to transfixing injury of the juxtahepatic IVC, by endovascular technique. After the initial volume replacement they were divided into two groups: control (GI) and experimental (GII). GI was maintained under observation and when MAP reached levels between 40 and 30 mm Hg the animals were submitted to laparotomy to evaluate bleeding and the lesion. GII was treated with SG and clinically followed by DUS and cavography after 4 (GIIA) and 8 weeks (GIIB), when they were sacrificed and IVC and SG were analyzed. GI presented a significant increase in peritoneal, vesical and IVC pressures, arterial hypotension, bradycardia, and death after 80 minutes. GII had a 100% survival rate, without clinical repercussions. DUS and cavography showed that all SG were patent. Doppler ultrasound showed a pattern of a monophasic pulsatile flux in all studied segments. On US, the measures of SG diameters in the 2nd (7.89 ± 1.20mm), 4th (7.24 ± 1.72mm) and 8th (8.04 ± 1.15mm) weeks did not show statistically significant differences. On cavography the measures of IVC diameters before the insertion of SG, immediately after its insertion and after 4 and 8 weeks did not show statistically significant differences between GIIA and GIIB. These data analyzed for the GII as a whole, showed statistically significant differences; IVC (11.74 ± 0.86mm) T=1.00 p=0.007, after the insertion of SG (12.86 ± 0.41mm) T=0.00 p=0.008 and in the late period (8.44 ± 2.00mm) T=0.00 p=0.005. The average rate of reduction in lumen diameter of SG was 27.43 ± 20,00%. The measures, in H2O cm of the IVC pressure, cranial (0.55 ± 0.50), caudal (1.15 ± 1.76) and in the interior of the SG (0.75 ± 0.63) did not show statistically significant differences. In the IVC study with SG, we observed the formation of a thicker neointima as compared to the media and intima layers. In the area of the lesion, the media layer was injured and cicatrized with fibroconjuctive tissue. In conclusion, a) we created an experimental model of transfixing lethal injury of the juxtahepatic IVC by endovascular technique with a mortality rate of 100% after 80 minutes of the injury, causing an important hemoperitonium with significant increase in peritoneal pressure, b) we treated this lesion with SG, with a survival rate of 100%, c) we verified through DUS and cavography the patency of the SG after 2, 4 and 8 weeks of treatment, and d) we observed significant thickening of the neointima with a reduction of 27% in the diameter of the lumen, without clinical repercussion or pressure gradient increase
74

Estudo anatômico das veias hepáticas em cães sem raça definida (Canis familiaris - Linnaeus, 1758) / Anatomical study of the hepatic veins in crossbred dogs (Canis familiaris L. 1758)

Luciano de Morais Pinto 05 April 1999 (has links)
A forma externa do fígado é extremamente variada dentre os mamíferos. Esses tipos de arquitetura apresentam arranjos vasculares próprios, de acordo com o maior ou menor grau de fissuração deste órgão entre as espécies, assumindo particular importância no estabelecimento da segmentação porto-bilo-arterial. Esta importância, no entanto, deve-se principalmente ao fato das veias hepáticas não obedecerem o mesmo trajeto da circulação funcional, o que nos impele a estabelecer um novo padrão segmentar. Mediante observações de peças isoladas, fixadas in situ, como também de moldes plásticos do sistema venoso hepático obtidos mediante corrosão e de peças injetadas com látex Neoprene e posteriormente dissecadas, podemos identificar cinco veias hepáticas principais. Estas veias podem ser divididas em dois grupos: as veias segmentares, que drenam um segmento apenas, e veias intersegmentares, que drenam mais de um segmento. São elas: veia segmentar do processo papilar (segmento I), apresenta-se como vaso único que desemboca na veia cava caudal. Veia intersegmentar esquerda, formada por 2 ou 3 veias segmentares laterais esquerdas que drenam o lobo lateral esquerdo (segmento II) e 1 a 5 veias segmentares paramedianas esquerdas, que drenam o lobo medial esquerdo (segmento III). Veia intersegmentar sagital, formada pela confluência entre a veia segmentar do processo quadrado (segmento IV) e a veia segmentar medial do lobo medial direito (segmento V). Veia segmentar direita, formada por duas ou três veias segmentares laterais direita que drenam o lobo lateral direito (segmento VI). Veia segmentar do processo caudato (segmento VII) que drena o processo caudado. / The external form of the liver is extremely varied among the mammals. These architecture types present an own vascular arrangements, in agreement with the largest or smaller degree of fissuring of this organ among the species, assuming private importance in the establishment of the port-bilo-arterial segmentation. This importance however, is due mainly to the fact that the hepatic veins don\'t obey the same itinerary of the functional circulation what it impels us to establish a new pattern to segmental. By means of observations of pieces isolated, fastened in situ, as well as of plastic molds of the hepatic veins system obtained by means of corrosion and of pieces injected with Neoprene latex and later on dissected, we can identify five main hepatic veins. These veins can be divided in two groups: the segmental veins, that draining a segment just, and intersegmental veins, that draining more than a segment. They are them: left intersegmental vein, formed by 2 or 3 lefts segmental lateral veins that draining the left lateral lobe (segment II) and 1 to 5 left segmental paramedians veins, that draining the left medial lobe (segment III), sagital intersegmental vein, formed by the confluence among the segmental vein of the quadrate lobe (segment IV) and the segmental medial vein of the right medial lobe (segment V), segmental vein of the caudate process (segment VII), draining the caudate process and the right segmental vein, formed by 2 or 3 segmental lateral right veins that draining the right lateral lobe (segment VI). the segmental vein of the papillary process (segment I) comes as only vessel that ends in the cava caudal vein.
75

Hemodinâmica venosa de membros inferiores em mulheres durante a gestação e após o parto / Venous lower limb hemodynamics during Pregnancy and puerperium

Leandro Augusto Gardenghi 19 February 2016 (has links)
Contexto: Existem controvérsias na literatura médica sobre potenciais alterações da hemodinâmica venosa dos membros inferiores durante a gravidez. Objetivo: Estudar a drenagem venosa em membros inferiores e suas alterações na gestação (1º, 2º e 3º trimestres) e pós-parto mediante Mapeamento Dúplex (MD) das veias profundas e superficiais e a Pletismografia a Ar (PGA). População: Foram recrutadas vinte mulheres primigestas, sem doença venosa prévia, junto aos Núcleos de Saúde da Família ligados ao Centro de Saúde Escola da FMRP-USP. Métodos: O estudo hemodinâmico venoso nos membros inferiores foi realizado empregando-se dois métodos não invasivos: o MD e a PGA. Foram registrados os diâmetros e os refluxos das principais veias (femoral comum, femoral, poplítea, safena magna e parva) dos membros inferiores por meio do MD. Foram avaliados pela PGA: o índice de enchimento venoso (IEV), a fração de ejeção (FE), a fração de volume residual (FVR) e o esvaziamento venoso (OF-outflow). Todos os registros foram obtidos em 3 diferentes períodos da gestação e no pós-parto. Os dados foram estatisticamente analisados e considerou-se p?0,05. Resultados: Houve aumento do diâmetro venoso no território da femoral comum e da safena magna infravalvar bilateralmente, nos 2º e 3º trimestres. Na PGA, registrou-se diminuição da FVR bilateral, elevação do IEV à direita e aumento do OF bilateral no decorrer da gestação. Observou-se edema em 4 (15%) gestantes no segundo trimestre e 11 (55%) no terceiro trimestre. Quanto ao refluxo, documentouse um caso no 2º trimestre no território da safena magna supravalvar esquerda (5%) e mais dois casos no 3º trimestre (15%), sendo uma no território da safena magna infravalvar esquerda e outra gestante com refluxo nos territórios de safena magna infravalvar e safena parva esquerdas. Após o parto, houve regressão de todas essas alterações anatômicas e hemodinâmicas da drenagem venosa dos membros inferiores. Conclusão: Apesar do aumento significativo dos diâmetros das veias femorais comuns e safenas magnas infravalvares bilateralmente, diminuição da FVR bilateral, elevação do IEV à direita, aumento do OF durante a gestação, todas essas alterações retornaram aos parâmetros anatômicos e hemodinâmicos venosos iniciais, após o parto / Background: The relation between pregnancy and venous reflux is still misunderstood and some authors question if pregnancy is the main cause of venous reflux and venous disease. Objective: analyze venous hemodynamics in healthy primigravidae during the first, second and third trimester of pregnancy and in the puerperium. Methods: prospective study with 20 primigravidae evaluated in the first, second and third trimester of pregnancy and postpartum. Duplex scan evaluated venous diameters and reflux; air plethysmography evaluated venous filling index (VFI), ejection fraction (EF), residual volume fraction (RVF), outflow fraction (OF )in both limbs. OF in the right limb while the patient was in left lateral decubitus position was also evaluated. Results: During pregnancy, there was bilateral increase in venous diameters in common femoral and infravalvar great saphenous veins; occurrence of reflux in the left surpravalvar great saphenous vein in one patient (5%) in the second trimester; and occurrence of reflux more other two patents (15%) in the third trimester: one in the left infravalvar great saphenous vein, and other in the left popliteal and small saphenous vein. All these alterations observed during pregnancy disappeared after delivery. VFI decreased after delivery in the left limb, but increased progressively in the right limb, returning to basal level after delivery; EF did not change; RVF decreased during pregnancy, mainly in left limb, and returned to basal level after delivery; OF increased during pregnancy and returned to basal levels after delivery; OF in left lateral decubitus did not change. Conclusion: pregnancy caused a diameter increase in bilateral common femoral and great saphenous veins, unilateral right increase in VFI, bilateral decrease in the RVF and bilateral increase in OF. All these parameters returned to initial status after delivery
76

Tratamento de varizes dos membros inferiores com laser endovenoso em pacientes com ulcera em atividade e medida das temperaturas intra e perivenosas durante o procedimento / Endovenous laser treatment for varicose veins in patients with active ulcers. Measurement of intravenous and perivenous temperatures during the procedure

Viarengo, Luiz Marcelo Aiello 27 June 2007 (has links)
Orientadores: Fabio Husemann Menezes, João Poterio Filho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-09T07:32:33Z (GMT). No. of bitstreams: 1 Viarengo_LuizMarceloAiello_D.pdf: 5372848 bytes, checksum: 053f8a2b3ec69d775d15f4e631b7f2c9 (MD5) Previous issue date: 2007 / Resumo: Este estudo foi desenvolvido para avaliar, prospectivamente, os resultados do tratamento de varizes com úlcera em atividade com laser endovenoso (EVL), comparando com um grupo sob tratamento clínico, durante um ano. Foram estudados 52 pacientes consecutivos portadores de varizes com úlcera em atividade há mais de um ano, divididos em dois grupos aleatórios. O Grupo I, tratamento clínico, formado por 25 indivíduos; o Grupo II, tratamento com EVL, constituído por 27 indivíduos. Todos os pacientes foram estudados com ultra-som no início e término do estudo. Os pacientes do Grupo II foram seguidos com ultra-som com 7 dias, 30 dias e a cada 3 meses. As áreas das feridas foram avaliadas a cada 3 meses. O laser utilizado para o tratamento endovenoso das varizes tronculares foi um laser de diodo, com comprimento de onda de 980 nanômetros, com potência nominal de 15W com fibra óptica condutora de laser de 600 microns, introduzida endovenosamente por punção percutânea dirigida por ultra-som e com emprego de anestesia local por infiltração intumescente associado a sedação leve por via oral com 15mg de Midazolam®. As medidas de temperaturas intra e perivenosa foram realizadas com um termômetro digital acoplado ao computador. Em 12 meses, 81,5% das feridas dos pacientes do Grupo II estavam cicatrizadas enquanto no Grupo I apenas 24% estavam cicatrizadas. A recorrência de úlcera foi de 44,4% no Grupo I, sem nenhuma recorrência no Grupo II. A área média das feridas no Grupo I reduziu de 18,04cm² para 13,16cm² ao final de um ano, enquanto no Grupo II reduziu de 22,7cm² para 3,64cm² (p<0,05). A temperatura média registrada foi de 79,3ºC no intravenoso e de 43,0ºC nos tecidos perivenosos. Não houve efeito adverso importante. O tratamento de varizes com laser endovenoso em pacientes com úlcera venosa em atividade mostrou-se seguro, com taxa de cicatrização das feridas superior à dos pacientes com tratamento clínico no prazo de um ano, e não houve recorrência / Abstract: Conventional saphenous vein stripping is difficult to be indicated for the treatment of varicose veins in patients classified as CEAP C4, C5 or C6. This study was developed to consecutively evaluate treatment results for varicose veins with active ulcers using endovenous laser (EVL), compared to a groupundergoing clinical treatment, during a year. Fifty-two consecutive patients presenting with varicose veins with active ulcers for more than a year were divided for treatment into two randomized groups: Group I, clinical treatment, composed of 25 subjects, were submitted to elastic or inelastic compression therapy according to individual medical recommendation; Group II, EVL treatment, composed of 27 subjects, were submitted to great and or small saphenous vein ablation with a 980 nm diode endovenous laser, plus the clinical treatment. Intravenous and perivenous temperatures were measured continuously with a digital thermometer connected to a computer during the EVL treatment. All patients were followed for 12 months and studied with ultrasound at the beginning and end of the study. The ulcers¿areas were evaluated initially and at every 3 months. In 12 months, 81.5% of the wounds in patients in Group II and only 24% in patients in Group I had healed. Ulcer recurrence rate was 44.4% in Group I. The average wound area in Group I decreased from 18.04cm² to 13.16cm² at the end of the year. In Group II, the wound area decreased from 22.7cm² to 3,64cm² (p<0,05). Mean intravenous and perivenous temperatures of 79.3ºC and 43.0ºC were recorded. In conclusion, the treatment for varicose veins with endovenous laser (EVL) as described is safe in patients with active ulcers. Wounds healed faster than in patients undergoing clinical treatment alone during a one-year period. There was no ulcer recurrence in patients treated with EVL / Doutorado / Cirurgia / Doutor em Cirurgia
77

Punção periférica da jugular externa para coleta de células progenitoras hematopoéticas de sangue periférico / Peripheral puncture of the external jugular for collecting hematopoietic progenitor cells from peripheral blood

Nixon Ramos da Silva 08 March 2017 (has links)
Introdução: O transplante autólogo de células progenitoras hematopoéticas é indicado para tratamento de várias doenças neoplásicas e não-neoplásicas, tais como linfoma, mieloma múltiplo e doenças autoimunes. Para isso, é imprescindível coletar as células progenitoras hematopoéticas (CPHs), em geral mobilizadas para o sangue periférico, por meio de equipamentos de aférese e acesso venoso adequado, seja de veia periférica seja de veia central quando a primeira não for adequada. Usualmente, o acesso periférico se dá por veia da fossa cubital. Entretanto, a veia jugular externa também poderia ser uma opção em pacientes em que a veia cubital não proporcionar fluxo sanguíneo adequado, uma possibilidade ainda muito pouco explorada nesse contexto. Objetivos: Avaliar a viabilidade de coletar CPHs pela veia jugular externa em pacientes que não tem acesso por meio da veia da fossa cubital.Métodos: Trata-se de estudo observacional do tipo transversal, com coleta retrospectiva dos dados por meio da análise das fichas médicas arquivadas no Hemonúcleo do Hospital de Câncer de Barretos. A amostra foi composta de 26 indivíduos, sendo que 13 (50%) dos participantes tiveram a punção da veia jugular externa e os outros 13 (50%) foram extraídos aleatoriamente do conjunto de 913 pacientes que tiveram a punção da veia da fossa cubital para equilíbrio numérico das amostras, no período de 2007 a 2014. Resultados: Dos 26 participantes do estudo, 19 (76,9%) foram do sexo masculino e 7 (23,1%) do sexo feminino. Entre as doenças, o mieloma foi a mais prevalente, não houve diferença quanto ao diagnóstico entre os dois grupos fossa cubital e jugular. As médias de células CD34+ coletadas no grupo fossa cubital e no grupo jugular foram de 10,0 x 106/kg e 5,1 x 106/kg, respectivamente (p=0,20). As volemias processadas foram de 4,2 e 4,4 para os grupos fossa cubital de jugular (p=0,12). O fluxo médio de aspiração do sangue foi de 69±17 mL/minuto e 62±17 mL/minuto (p=0,29). Conclusão: Há viabilidade da coleta de CPH por via jugular externa / Introduction: Autologous hematopoietic progenitor cell transplantation is indicated for the treatment of various neoplastic and non-neoplastic diseases, such as lymphoma, multiple myeloma, and autoimmune diseases. For this, it is essential to collect the hematopoietic progenitor cells (CPHs), usually mobilized into the peripheral blood, by means of apheresis devices and adequate venous access, either peripheral vein or central vein when the former is not adequate. Usually, the peripheral access is by the ulnar fossavein. However, the external jugular vein could also be an option in patients where the ulnar vein does not provide adequate blood flow, a possibility still very little explored in this context. Objectives: To evaluate the feasibility of collecting CPHs through the external jugular vein in patients who do not have access through the ulnar fossa vein. Methods: It is an observational cross-sectional study, with retrospective data collection through the analysis of the medical records filed at the Barretos Cancer Hospital. The sample consisted of 26 individuals; 13 (50%) of the participants had external jugular vein puncture and the other 13 (50%) were randomly extracted from a set of 913 patients who had ulnar fossa vein puncture to numerical equilibrium of the samples from 2007 to 2014. Results: Of the 26 participants in the study, 19 (76.9%) were male and 7 (23.1%) were female. Among the diseases, myeloma was the most prevalent; there was no difference in diagnosis between the two groups of ulnar and jugular fossa. The mean CD34 + cells collected in the cubital fossa group and in the jugular group were 10.0 x 106/kg and 5.1 x 106/kg, respectively (p=0.20). The blood volumes processed were 4.2 and 4.4 for the jugular fossa group (p=0.12). The mean blood aspiration flow was 69 ± 17 mL/min and 62 ± 17 mL/min (p=0.29). Conclusion: there is viability of the collection of CPHs by external jugular vein
78

Image analysis tool for geometric variations of the jugular veins in ultrasonic sequences : Development and evaluation

Westlund, Arvid January 2018 (has links)
The aim of this project is to develop and perform a first evaluation of a software, based on the active contour, which automatically computes the cross-section area of the internal jugular veins through a sequence of 90 ultrasound images. The software is intended to be useful in future research in the field of intra cranial pressure and its associated diseases. The biomechanics of the internal jugular veins and its relationship to the intra cranial pressure is studied with ultrasound. It generates data in the form of ultrasound sequences shot in seven different body positions, supine to upright. Vein movements in cross section over the cardiac cycle are recorded for all body positions. From these films, it is interesting to know how the cross-section area varies over the cardiac cycle and between body positions, in order to estimate the pressure. The software created was semi-automatic, where the operator loads each individual sequence and sets the initial contour on the first frame. It was evaluated in a test by comparing its computed areas with manually estimated areas.  The test showed that the software was able to track and compute the area with a satisfactory accuracy for a variety of sequences. It is also faster and more consistent than manual measurements. The most difficult sequences to track were small vessels with narrow geometries, fast moving walls, and blurry edges. Further development is required to correct a few bugs in the algorithm. Also, the improved algorithm should be evaluated on a larger sample of sequences before using it in research.
79

Primary saphenous vein insufficiency:prospective studies on diagnostic duplex ultrasonography and treatment with endovenous radiofrequency-resistive heating

Rautio, T. (Tero) 07 July 2002 (has links)
Abstract The purpose of the present research was (I-II) to evaluate the effects of clinical, hand-held Doppler (HHD) and duplex ultrasonographic examinations on the planning of operative procedure for primary varicose veins, (III) to assess the feasibility, safety and efficacy of endovenous saphenous vein obliteration with radiofrequency-resistive heating and (IV) to compare endovenous saphenous vein obliteration with conventional stripping operation in terms of short-term recovery and costs. Sixty-two legs (in 49 consecutive patients) and 142 legs (in 111 consecutive patients) with primary uncomplicated varicose veins were examined clinically and with HHD and duplex ultrasonography for planning the subsequent treatment. At the saphenous-femoral junction (SFJ) and at the saphenous-popliteal junction (SPJ), sensitivity was 56-64% and 23%, specificity 93-97% and 96%, positive predictive value 97-98% and 43% and negative predictive value 44-45% and 91%, respectively. In 9% of the cases, the treatment plan was modified on the basis of the duplex ultrasound findings. The present study showed that, in primary uncomplicated varicose veins, the accuracy of HHD is unsatisfactory. Thirty legs of 27 patients with varicose veins were treated using an endovenous catheter (Closure® System, VNUS Medical Technologies, Inc., Sunnyvale, CA), which was inserted under ultrasound guidance via a percutaneous puncture or a skin incision. The persistence of vein occlusion and complications potentially attributable to the endovenous treatment were assessed at 1-week, 6-week, 3-month, 6-month and 1-year follow-up visits. By the time of the last follow-up visit, occlusion of the treated segment of the LSV had been achieved in 22 (73.3%) legs. Persisting patency or recanalization of LSV was detected in 8 legs (26.7%). Postoperative complications included saphenous nerve paresthesia in 3 legs (10%) and thermal skin injury in one limb (3.3%). Twenty-eight selected patients admitted for operative treatment of varicose veins in the tributaries of the primary long saphenous were randomly assigned to endovenous obliteration (n = 15) or stripping operation (n = 13). The patients were followed up for 7-8 weeks postoperatively and examined by duplex ultrasonography. The comparison of costs included both direct medical costs and costs due to lost of productivity. All operations were successful, and the complication rates were similar in the two groups. The sick leaves were significantly shorter in the endovenous obliteration group [6.5 (SD 3.3) vs. 15.6 (SD 6.0), 95 % CI 5.4 to 12.9, p &lt; 0.001, t-test]. When the value of the lost working days was included, the endovenous obliteration was societally cost-saving.
80

Exercice, veines et maladie veineuse chronique : effets de l'exercice et des conditions de récupération / Exercise, veins and chronic venous disease : effecs of exercise and recovery conditions

Beliard, Samuel 06 November 2017 (has links)
Résumé : Le rôle du réseau veineux est central dans la fonction cardiovasculaire, pourtant, au regard de la littérature scientifique, il apparaît comme le« parent pauvre » comparé au cœur ou au réseau artériel. Ce constat vaut aussi bien pour la compréhension de l'hémodynamique veineuse que pour l'analyse physiopathologique de la maladie veineuse chronique en général et plus particulièrement lorsque le lien est fait avec la situation d'exercice. Nos différentes investigations avaient pour buts d'une part de mieux comprendre les adaptations du système veineux lors de l'activité physique et lors de la phase de récupération post-exercice et d'autre physiopathologiques de l'hyper pression veineuse sur la microcirculation chez le sujet atteint d'une pathologie veineuse. Ils ont également apporté une meilleure compréhension de la phase de récupération post-exercice et des effets bénéfiques des méthodes de récupération sur la performance et sur les adaptations vasculaires. L'interdépendance entre les différents secteurs (cœur, artères, microcirculation, veines) du système cardiovasculaire est un élément essentiel mis en évidence dans nos différents travaux. Ainsi, nous avons démontré que l'hémodynamique veineuse ne pouvait être analysée de manière isolée, mais au contraire part d'évaluer l'impact de la maladie veineuse chronique sur l'activité physique et réciproquement. Pour cela nous avons étudié les effets aigus de l'activité physique sur le fonctionnement de l'hémodynamique veineuse (évaluation de la pompe veineuse surale), et les effets de différentes méthodes de récupération (compression, immersion, électro stimulation neuro musculaire). Par ailleurs nous avons exploré les conséquences de la pathologie veineuse sur la réalisation d'une activité physique à travers l'analyse de la claudication veineuse. Les principaux résultats de nos travaux ont permis de mieux appréhender les adaptations de l'hémodynamique veineuse liées à l'exercice chez le sujet sain d'une part et de mieux comprendre les conséquences qu'elle devait être évaluée dans sa globalité, en mesurant les implications sur le remplissage cardiaque en aval et sur les échanges au niveau tissulaire en amont, et en recherchant la part du réseau splanchnique et celle du réseau des membres aux propriétés bien différentes sur le retour veineux systémique. En conclusion, nous avons comblé une partie des lacunes de la littérature en permettant une meilleure appréhension des relations veines, exercice physique, récupération et pathologie veineuse. Cependant, des interrogations persistent concernant la méthodologie à mettre en place pour l'évaluation du réseau veineux et les effets chroniques de la pratique intensive d'une activité physique sur la maladie veineuse chronique. / The role of the venous system is central to cardiovascular fonction, yet, in terms of scientific literature, it appears to be the "poor relation" compared to the heart or arterial system. This is true both for the physiological understanding of venous hemodynamics and for the pathophysiological analysis of chronic venous disease and more particularly when the link is made with exercise. The aim of our investigations was to better understand the adaptations of the venous system during physical activity and during the post-exercise recovery period and, to evaluate the impact of chronic venous disease on physical activity and vice versa. We have studied the acute effects of physical activity on venous hemodynamics (evaluation of the calf venous pump), and the effects of various recovery methods ( compression, immersion, calf low frequency electrical stimulation), and we have also explored the consequences of chronic venous disease upon physical activity through the analysis of venous claudication. The main results of our work enabled a better understanding of the adjustments in venous hemodynamics linked to exercise in healthy subjects and to better understand the pathophysiological consequences of high venous pressure on the microcirculation of patients with chronic venous disease. Our findings also provide a detailed understanding of venous hemodynamics during post-exercise recovery and the positive effects of recovery methods on both performance and vascular adjustments. The interdependence of the different organs and tissues (heart, arteries, microcirculation, veins) of the cardiovascular system is an essential element highlighted in this work. Thus, we demonstrated that venous hemodynamics could not be analyzed in isolation, but rather that it should be assessed as a whole by measuring implications on cardiac filling and on tissue exchange, and looking for the part of the splanchnic system and limbs system on systemic venous return. ln conclusion, we have filled some of the gaps in the literature by examining the relationships between veins, physical exercise, recovery and venous pathology. However, questions remain regarding the methodology to be implemented for the evaluation of the venous system and the chronic effects of the intensive physical activity practice on the chronic venous disease prevalence

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