A system for vessel characterization aimed at detecting deep vein thrombosis (DVT) in the lower limbs has been developed and evaluated using ultrasound image processing, location and force sensors measurements, blood flow information and a protocol based on the current clinical standard, compression ultrasound. The goal is to provide an objective and repeatable system to measure DVT in a rapid and standardized manner, as this has been suggested in the literature as an approach to improve overall detection of the disease. The system uses a spatial Kalman filter-based algorithm with an elliptical model in the measurement equation to detect vessel contours in transverse ultrasound images and estimate ellipse parameters, and temporal constant velocity Kalman filters for tracking vessel location in real-time. The vessel characterization also comprises building a 3-D vessel model and performing compression and blood flow assessments to calculate measures that indicate the possibility of DVT in a vessel. A user interface designed for assessing a vessel for DVT was also developed. The system and components were implemented and tested in simulations, laboratory settings, and clinical settings. Contour detection results are good, with mean and rms errors ranging from 1.47-3.64 and 3.69-9.67 pixels, respectively, in simulated and patient images, and parameter estimation errors of 5%. Experiments showed errors of 3-5 pixels for the tracking approaches. The measures for DVT were evaluated, independently and integrated in the system. The complete system was evaluated, with sensitivity of 67-100% and specificity of 50-89.5%. System learnability and memorability were evaluated in a separate user study, with good results. Contributions include a segmentation approach using a full parameter ellipse model in an extended Kalman filter, incorporating multiple measurements, an alternate sampling method for faster parameter convergence and application-specific initialization, and a tracking approach that includes a sub-sampled sum of absolutes similarity calculation and a method to detect vessel bifurcations using flow data. Further contributions include an integrated system for DVT detection that can combine ultrasound B-mode, colour flow and elastography images for vessel characterization, a system interface design focusing on usability that was evaluated with medical professionals, and system evaluations through multiple patient studies.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 81-88). Also available via the Internet.

Introduction: The reason for the inability of performing the liver resection for colorectal carcinoma metastasis is usually insufficient remnant liver parenchyma after liver resection (future liver remnant volume - FLRV). The current standard method of increasing FLRV is the embolization of the branch of portal vein (portal vein embolization - PVE) on the side of the tumor, and then suspended after hypertrophy of the non-embolised lobe liver resection. Unfortunately, there are some patients who do not increase liver volume despite perfectly executed PVE. Besides that, FLRV occurs during the time necessary for hypertrophy progression of metastatic disease. Therefore, we are trying to find the appropriate way to encourage the growth of remaining liver parenchyma and accelerate hypertrophy of the contralateral liver lobe. From our previous experience (IGA MZ NS 10240), it is possible to be optimistic that there hope is the way of hematopoietic progenitor cells (HPC - adult stem cells) after previous PVE to non-embolised branches of the portal vein. These cells do not only accelerate liver regeneration, but are also able to improve its function (function of the liver) which is especially important for patients after neoadjuvant chemotherapy (steatohepatitis or steatofibrosis), and for patients with...

Objectives: Pelvic vein incompetence (PVI) has been suggested as a cause for chronic pelvic pain. The overall objective of this thesis is to determine how PVI affects women, identify suitable methods of diagnosis and provide evidence regarding its association with chronic pelvic pain. This thesis will also evaluate the evidence behind its treatment. Methods: Four observation studies were completed during this thesis. A characterisation study encompassing 120 participants was performed to determine symptoms commonly experienced by women with PVI. Two observation studies analysed the ability of trans-vaginal ultrasound to detect PVI and compared its accuracy with reflux venography; considered the reference standard. A further 70 participants were recruited in a case-control study to determine the prevalence of PVI in women with and without chronic pelvic pain. A randomised control trial treating women with PVI and pelvic pain was also designed. Results: Women with PVI had an increased frequency of CPP when compared with healthy controls or women with varicose veins. This pain was associated with the menstrual cycle and intercourse. It was also found to frequently radiate into the upper thighs. Trans-vaginal ultrasound was shown to have a sensitivity and positive predictive value of 100% and 95% respectively when compared with reflux venography. The frequency of PVI in women with chronic pelvic pain was found to be 47% compared with 25% in women with no history of CPP (p < 0.001). Conclusion: The results of this thesis suggest PVI to be a possible cause of CPP in women and likely to be under-diagnosed. It can be identified by trans-vaginal ultrasound although the degree of accuracy is still yet to be determined. PVI merits further research and attention from clinicians and researchers. The proposed randomised control trial is needed both to further understanding of the role of PVI in CPP and to assess the efficacy of an under-researched treatment approach currently used in practice.

Made available in DSpace on 2014-06-11T19:32:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-11-14Bitstream added on 2014-06-13T21:04:42Z : No. of bitstreams: 1 tofano_vac_dr_botfm.pdf: 984641 bytes, checksum: d4fcddf13acc4d52c783e4c30966c9b0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A trombose venosa profunda (TVP) caracteriza-se pela formação aguda de um trombo no interior das veias profundas. É uma doença de alta incidência e de grande importância clínica e epidemiológica devido à sua morbimortalidade, sendo atualmente, considerada multifatorial. São vários os fatores de risco genéticos e/ou adquiridos relacionados à TVP e a compreensão da interação destes, permite melhor entender esta doença, não só devido aos seus sintomas de fase aguda mas, principalmente, por sua complicação mais temida, a embolia pulmonar e, a longo prazo, a síndrome pós-trombótica (SPT), que apresenta importante morbidade, inclusive com repercussões sócio-econômicas. A avaliação a longo prazo, clínica e ultrassonográfica, de pacientes com diagnóstico de TVP, visando verificar a incidência e gravidade da SPT é necessária para a compreensão da evolução destes pacientes. Desconhecemos a existência de trabalhos em nosso meio, que avaliem a evolução tardia da TVP. Objetivo: Determinar a evolução a longo prazo de pacientes com TVP de membros, portadores de trombofilia e verificar se existem diferenças na evolução de pacientes trombofílicos e não trombofílicos. Método: Num estudo coorte retrospectivo foram avaliados os prontuários de 275 pacientes atendidos no Hospital das Clínicas da Faculdade de Medicina de Botucatu-Unesp, dos quais foram identificados 60 pacientes trombofílicos, sendo possível contactar 40 deles para consulta, dos quais 39 pacientes aceitaram participar do estudo. Foram selecionados 25 pacientes com diagnóstico de TVP, não trombofílicos, pareados para sexo e idade, para comparação com o grupo trombofílico. Durante a consulta foi preenchido um protocolo que continha as seguintes variáveis: dados demográficos, profissão, antecedentes pessoais e antecedentes obstétricos (se mulher), antecedentes familiares com relação... / Deep vein thrombosis (DVT) is characterized by the acute formation of a thrombus in the interior of the deep veins. It is a disease of high incidence and great clinical and epidemiological importance due to its morbimortality, being presently considered multifactorial. The genetic and/or acquired risk factors related to DVT are various and understanding their interaction allows a better comprehension of this illness, due to both symptoms of the acute stage and, mainly, its most feared complication, the pulmonary embolism and, in long term, the post-thrombotic syndrome (PTS), which presents important morbidity, inclusively with social and economical repercussions. The long-term clinical and ultrasound evaluation of patients with DVT diagnosis, aiming to verify the incidence and seriousness of PTS, is necessary to understand the evolution of these patients. We are not aware of the existence of works in our area which evaluate the late evolution of DVT. Objective: To determine the long-term evolution of patients with DVT of limbs, carriers of thrombophilia, and verify the existence of differences in the evolution of thrombophilic and non-thrombophilic patients. Method: In a retrospective cohort study, the medical registers of 275 patients attended at the Clinics Hospital of the School of Medicine of the Paulista State University, in Botucatu, São Paulo, Brazil, were evaluated, from which 60 thrombophilic patients were identified. It was possible to contact 40 of them for appointment, from which 39 patients accepted to participate in the study. 25 non-thrombophilic patients, paired for sex and age, were selected with DVT diagnosis, for comparison with the thrombophilic group. During the appointment, a protocol was filled in, containing the following variables: demographic data, occupation, personal antecedents and obstetric antecedents (if woman), familiar antecedents concerning thrombosis... (Complete abstract click electronic access below)

Cell-derived microvesicles (MVs) are naturally released into the human circulation and an increase in the concentration of certain MV populations have been observed after exercise. However, the MV appearance dynamics, the exercise-related stimuli that induce their formation and physiological relevance are poorly understood. Hence, the overall objectives of this thesis were to: 1) characterise the circulating platelet (PMV) and endothelial-derived MVs (EMVs) responses during exercise and recovery, as well as their arteriovenous dynamics, 2) investigate the potential role of haemodynamic forces on MVs formation in vivo by vascular shear stress manipulations, and 3) explore the putative proliferative, chemotactic and angiogenic potential of exercise-derived MVs upon human vascular endothelial cells in vitro. Chapter 5 of this thesis describes the time-course of MV appearance in response to prolonged cycling, and demonstrates that intravascular [PMV] increases during and after exercise performed in the heavy intensity domain, whereas [EMV] remains unaltered. Moreover, [PMV] during exercise was related to estimates of vascular shear stress and plasma noradrenaline levels. Results from chapter 6 revealed that PMVs increased in the arterial circulation during passive heat stress, and in the arterial as well as venous circulation during short duration very heavy exercise engaging either a large or small muscle mass. The increases in [PMV] were not directly linked to local changes in vascular shear stress through heat stress and exercise, indicating a systemic PMV response. Finally, chapter 7 revealed that exercise-derived MVs supported endothelial proliferation and migration, while displaying pro-angiogenic potential in vitro. In conclusion, results of this thesis provide original information about MV dynamics, by demonstrating that PMV increase systemically in the circulation not only after but during exercise involving a small and large muscle mass. This MV response seems to be modulated by exercise intensity, and is only partially linked to levels of vascular shear stress. Moreover, circulating MVs produced during exercise present stimulatory angiogenic and mitogenic effects upon endothelial cells in vitro, suggesting a novel potential link between vascular adaptation and exercise training.

Orientador: Francisco Humberto de Abreu Maffei / Banca: Hamilton Almeida Rollo / Banca: Adilson F. Paschôa / Banca: Newton Key Hokama / Banca: Cyrillo C. Filho / Resumo: A trombose venosa profunda (TVP) caracteriza-se pela formação aguda de um trombo no interior das veias profundas. É uma doença de alta incidência e de grande importância clínica e epidemiológica devido à sua morbimortalidade, sendo atualmente, considerada multifatorial. São vários os fatores de risco genéticos e/ou adquiridos relacionados à TVP e a compreensão da interação destes, permite melhor entender esta doença, não só devido aos seus sintomas de fase aguda mas, principalmente, por sua complicação mais temida, a embolia pulmonar e, a longo prazo, a síndrome pós-trombótica (SPT), que apresenta importante morbidade, inclusive com repercussões sócio-econômicas. A avaliação a longo prazo, clínica e ultrassonográfica, de pacientes com diagnóstico de TVP, visando verificar a incidência e gravidade da SPT é necessária para a compreensão da evolução destes pacientes. Desconhecemos a existência de trabalhos em nosso meio, que avaliem a evolução tardia da TVP. Objetivo: Determinar a evolução a longo prazo de pacientes com TVP de membros, portadores de trombofilia e verificar se existem diferenças na evolução de pacientes trombofílicos e não trombofílicos. Método: Num estudo coorte retrospectivo foram avaliados os prontuários de 275 pacientes atendidos no Hospital das Clínicas da Faculdade de Medicina de Botucatu-Unesp, dos quais foram identificados 60 pacientes trombofílicos, sendo possível contactar 40 deles para consulta, dos quais 39 pacientes aceitaram participar do estudo. Foram selecionados 25 pacientes com diagnóstico de TVP, não trombofílicos, pareados para sexo e idade, para comparação com o grupo trombofílico. Durante a consulta foi preenchido um protocolo que continha as seguintes variáveis: dados demográficos, profissão, antecedentes pessoais e antecedentes obstétricos (se mulher), antecedentes familiares com relação... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Deep vein thrombosis (DVT) is characterized by the acute formation of a thrombus in the interior of the deep veins. It is a disease of high incidence and great clinical and epidemiological importance due to its morbimortality, being presently considered multifactorial. The genetic and/or acquired risk factors related to DVT are various and understanding their interaction allows a better comprehension of this illness, due to both symptoms of the acute stage and, mainly, its most feared complication, the pulmonary embolism and, in long term, the post-thrombotic syndrome (PTS), which presents important morbidity, inclusively with social and economical repercussions. The long-term clinical and ultrasound evaluation of patients with DVT diagnosis, aiming to verify the incidence and seriousness of PTS, is necessary to understand the evolution of these patients. We are not aware of the existence of works in our area which evaluate the late evolution of DVT. Objective: To determine the long-term evolution of patients with DVT of limbs, carriers of thrombophilia, and verify the existence of differences in the evolution of thrombophilic and non-thrombophilic patients. Method: In a retrospective cohort study, the medical registers of 275 patients attended at the Clinics Hospital of the School of Medicine of the Paulista State University, in Botucatu, São Paulo, Brazil, were evaluated, from which 60 thrombophilic patients were identified. It was possible to contact 40 of them for appointment, from which 39 patients accepted to participate in the study. 25 non-thrombophilic patients, paired for sex and age, were selected with DVT diagnosis, for comparison with the thrombophilic group. During the appointment, a protocol was filled in, containing the following variables: demographic data, occupation, personal antecedents and obstetric antecedents (if woman), familiar antecedents concerning thrombosis... (Complete abstract click electronic access below) / Doutor

Orientador: Francisco Humberto de Abreu Maffei / Banca: Hamilton de Almeida Rollo / Banca: José Roberto Fioretto / Banca: Fausto Miranda Junior / Banca: Jorge David Aivazoglou Carneiro / Resumo: A importância do estudo da trombose venosa profunda (TVP) em crianças e adolescentes reside no impacto desta doença sobre a qualidade de vida desta população, tendo em vista sua longa expectativa de vida e a morbidade associada ao tromboembolismo venoso. Com o passar dos anos, a síndrome pós-trombótica e a recorrência podem deixar sequelas que vão desde dor crônica nos membros, edema e até úlceras de difícil cicatrização. A TVP em crianças está sendo melhor estudada nos últimos anos. Até então, seu diagnóstico e tratamento eram baseados em experiências individuais, pequenas séries de casos ou extrapolados das recomendações para adultos. Realizamos a presente revisão para melhor compreensão da epidemiologia, fisiopatologia, etiologia, diagnóstico, tratamento desta doença / Abstract: The study of deep vein thrombosis (DVT) in children and adolescents assesses the important impact of this disease on the quality of life of this population considering its long life expectancy and morbidity associated to venous thromboembolism. Within the years, the pos-thrombotic syndrome and recurrence can cause sequelae including chronic lower limb pain, edema and even hard cicatrization ulcer. Recently, DVT in children has been studied more appropriately. Previously, its diagnosis and treatment were based on individual experience, some serial cases or comparisons with recommendations to the adult treatments. This present study has been presented to better comprehend the epidemiology, physiopathology, etiology, diagnosis, treatment and prophylaxis of the deep vein thrombosis / Doutor

Foi realizado o estudo morfométrico e o estudo hemodinâmico da veia porta em vinte cães normais, de idade igual e inferior a 120 dias, e em cinco cães portadores de desvio portossistêmico, de idades entre 90 e 360 dias. Dois animais do grupo de cães portadores de desvio portossistêmico foram submetidos ao tratamento cirúrgico (colocação de anel ameróide) e avaliações subseqüentes ao procedimento cirúrgico foram realizados. Nos cães do grupo normal, as margens hepáticas apresentaram-se entre 1,50cm e 3,00cm depois da margem costal. As médias dos diâmetros médios da veia porta (VP), veia cava caudal (VCC) e aorta abdominal (AO) obtidas foram respectivamente, 0,38cm, 0,37cm e 0,41cm. As proporções entre os diâmetros médios VP/VCC e VP/AO apresentaram médias de 1,10 e 0,94, respectivamente. As médias das áreas de VP, VCC e AO mediram respectivamente, 0,12cm2, 0,11cm2 e 0,14cm2. No estudo hemodinâmico de VP destes animais, utilizando-se o ultra-som Doppler, a velocidade média de fluxo sangüíneo portal (VMFSP) mediu 17,77cm/s. A média de fluxo sangüíneo portal (FSP) mediu 83,11ml/min/kg. O índice de congestão (IC) apresentou média de 0,009. Para o grupo de cães portadores de desvio portossistêmico, o fígado apresentou redução de seu volume, sendo visibilizado entre 1,00cm e 2,00cm antes da margem costal. No estudo morfométrico, as médias dos diâmetros médios obtidos de VP, VCC e AO mensuraram respectivamente, 0,52cm, 0,79cm e 0,58cm. As proporções entre os diâmetros médios VP/VCC e VP/AO mediram respectivamente, 0,62 e 0,84. As médias das áreas de VP, VCC e AO mediram respectivamente, 0,22cm2, 0,56cm2 e 0,27cm2. Ao ultra-som Doppler a VMFSP mediu 26,10cm/s e a média do IC obtido foi de 0,009. Nos animais do grupo de cães portadores de desvio portossistêmico submetidos ao procedimento cirúrgico, foi observado aumento de volume hepático na semana seguinte à colocação do anel ameróide e a VMFSP manteve-se inferior a 19,50cm/s em todos exames subseqüentes à cirurgia no cão 1. / The morphometry and haemodynamic aspects of portal vein were studied in 20 normal dogs with less than 120 days of age and in 5 dogs presenting portosystemic shunting with ages between 90 and 360 days. 2 dogs of the group of animals with portosystemic shunting were submitted to surgical treatment, using a specialized device (ameroid constrictor). Subsequent evaluations were made after the surgical procedure. In the normal group the hepatic margins were seen 1.50cm to 3.00cm below de costal margin. Collected data indicated that the mean diameter of portal vein (VP), caudal vena cava (VCC) and abdominal aorta (AO) measured respectively, 0.38cm, 0.37cm and 0.41cm. The VP/VCC and VP/AO mean ratios were respectively, 1.10 and 0.94. The average of VP, VCC and AO areas were respectively, 0.12cm2, 0.11cm2 and 0.14cm2. The haemodynamic of portal vein was studied by ultrasound Doppler and the mean velocity of portal blood flow (VMFSP) measured was 17.77cm/s. It was verified that portal blood flow (FSP) average was 83.11ml/min/kg and the congestion index (IC) average was 0.009. In the group of animals presenting portosystemic shunting, the hepatic margins were seen 1.00cm to 2.00cm above the costal margin. The morphometry of VP, VCC and AO presented a mean diameter of 0.52cm, 0.79cm and 0.59cm, respectively. The VP/VCC and VP/AO mean ratios were respectively, 0.62 and 0.84. The average of VP, VCC and AO areas were respectively, 0.22cm2, 0.56cm2 and 0.27cm2. The haemodynamic study demonstrated that the VMFSP measured was 26.10cm/s and de IC average was 0.009. In the group of animals with portosystemic shunting which were submitted to surgical treatment, an increase of the liver size was seen from the first ultrasonographic evaluation. The measurements of VMFSP collected in the post surgical period were <= 19.50cm/s in dog 1.

Orientador: Fabio Husemann Menezes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-14T03:12:56Z (GMT). No. of bitstreams: 1 Rielli_Glauber.pdf: 567843 bytes, checksum: 4d042894d00f11bcc831e52dc91eb94b (MD5) Previous issue date: 2009 / Resumo: Objetivo: Avaliar em suínos a viabilidade, morbidade e mortalidade imediata do acesso vascular alternativo para hemodiálise através da punção da veia ázigos, guiada por vídeo-toracoscopia. Material e métodos: Oito suínos foram submetidos a punção da veia ázigos e posterior introdução do cateter de hemodiálise na posição central através de vídeo-toracoscopia em hemitórax esquerdo, com ligadura distal e reparo proximal da mesma com dupla laçada de fio de silicone para hemostasia para quando da retirada do cateter. Os animais foram monitorizados através de dados hematimétricos, gasometria, pressão invasiva e sacrificados ao final. Resultados: Em cinco animais o procedimento transcorreu semintercorrências, com fluxo adequado pelo cateter, sem hemorragia, em um tempo médio de duas horas. Em dois animais houve a necessidade de dissecção direta da veia ázigos através da conversão para toracotomia devido a perda do controle hemostático. Em um destes animais houve lesão do parênquima pulmonar sem comprometer a ventilação. Em um animal a veia não foi localizada por provável lesão na inserção do trocar. Não ocorreram óbitos durante o procedimento. Conclusão: A técnica se mostrou viável, mas com complicações técnicas relacionadas ao treinamento, tendo o potencial de ser utilizado como acesso venoso alternativo para hemodiálise. Outros estudos podem validar estes achados com o intuito de se utilizar em humanos sem acesso vascular para hemodiálise / Abstract: Purpose: The purpose of this acute experiment is to evaluate in the pigs the feasibility and immediate complications associated with the transpleural cannulation of the azygos vein performed under video-thoracoscopy. Material and Methods: Eight female pigs were submitted to central venous cannulation of the azygos vein guided by vodeo-thoracoscopy of the left side of the thorax. The azygos vein was ligated distally and secured proximally with a double silicone strand loop, intended to be used as bleeding control in case the catheter is withdrawn. Invasive blood pressure with hematimetric and gasometrical data was recorded during the procedure. All animals were sacrificed after the experiment. Results: All animals survived the experiment. There were five successful cannulations. There were two conversions to thoracotomy because of bleeding which, even if minor, hindered the view of the operation field and were successfully converted to thoracomy with direct cannulation of the vein. There was one lung injury caused by a retractor. There was one termination of the procedure because the azygos vein was not found probably because of a lesion during the trocar insertion. Conclusion: In conclusion, the video-thoracoscopic technique was found to be feasible with complications related to technical training and could become an alternative access in patients with unsuitable conventional central venous access. Further investigation could validate these findings / Universidade Estadual de Campi / Ciencias Medicas / Mestre em Cirurgia